94-30767. Hazardous Waste Management System; Identification and Listing of Hazardous Waste; Dye and Pigment Industries; Hazardous Waste Listing Determination Policy; and CERCLA Hazardous Substance Designation and Reportable Quantities; Proposed ...  

  • [Federal Register Volume 59, Number 245 (Thursday, December 22, 1994)]
    [Unknown Section]
    [Page 0]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 94-30767]
    
    
    [[Page Unknown]]
    
    [Federal Register: December 22, 1994]
    
    
    _______________________________________________________________________
    
    Part II
    
    
    
    
    
    Environmental Protection Agency
    
    
    
    
    
    _______________________________________________________________________
    
    
    
    40 CFR Part 261 et al.
    
    
    
    
    Hazardous Waste Management System; Identification and Listing of 
    Hazardous Waste; Dye and Pigment Industries; Hazardous Waste Listing 
    Determination Policy; and CERCLA Hazardous Substance Designation and 
    Reportable Quantities; Proposed Rules
    ENVIRONMENTAL PROTECTION AGENCY
    
    40 CFR Parts 261, 271, and 302
    
    [SWH-FRL-5122-5]
    RIN 2050-AD80
    
     
    Hazardous Waste Management System; Identification and Listing of 
    Hazardous Waste; Dye and Pigment Industries; Hazardous Waste Listing 
    Determination Policy; and CERCLA Hazardous Substance Designation and 
    Reportable Quantities
    
    AGENCY: Environmental Protection Agency.
    
    ACTION: Notice of proposed rulemaking.
    
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    SUMMARY: The U.S. Environmental Protection Agency (EPA) is proposing to 
    amend the regulations for hazardous waste management under the Resource 
    Conservation and Recovery Act (RCRA). EPA is listing, as hazardous, 
    five wastes generated during the production of dyes and pigments 
    because certain ways of disposing of these wastes may present a risk to 
    human health and the environment. EPA also is proposing not to list as 
    hazardous six other wastes from this industry, and to defer action on 
    three wastes due to insufficient information. The proposal would add 
    the toxic constituents found in the wastes to the list of constituents 
    that serve as a basis for classifying wastes as hazardous. This action 
    also describes EPA's policy on making listing determinations, and the 
    risk-based criteria used by the Agency.
        This action is proposed under the authority of Sections 3001(e)(2) 
    and 3001(b)(1) of the Hazardous and Solid Waste Amendments of 1984 
    (HSWA), which direct EPA to make a hazardous waste listing 
    determination for dye and pigment wastes. If finalized, this regulation 
    would regulate these wastes as hazardous wastes under Subtitle C of 
    RCRA. Additionally, this action proposes to designate the wastes 
    proposed for listing as hazardous substances subject to the 
    Comprehensive Environmental Response, Compensation, and Liability Act 
    (CERCLA). EPA is not taking action at this time to adjust the one-pound 
    statutory reportable quantities (RQs) for these substances.
    
    DATES: EPA will accept public comments on this proposed rule and on 
    EPA's hazardous waste listing determination policy until March 22, 
    1995. Comments postmarked after this date will be marked ``late'' and 
    may not be considered. Any person may request a public hearing on this 
    proposal by filing a request with Mr. David Bussard, whose address 
    appears below, by January 5, 1995.
    
    ADDRESSES: The official record of this proposed rulemaking is 
    identified by Docket Number F-94-DPLP-FFFFF and is located at the 
    following address. The public must send an original and two copies of 
    their comments to: EPA RCRA Docket Clerk, Room 2616 (5305), U.S. 
    Environmental Protection Agency, 401 M Street, SW., Washington, DC 
    20460.
        The Docket Number for comments on EPA's discussion of its listing 
    determination policy (see Section I.B) is F-94-LCN-FFFFF. The public 
    must send an original and two copies of their comments on EPA's policy 
    discussion to the above address. Such comments must be submitted 
    separately from comments on the dye and pigment listing determinations, 
    and must reference Docket Number F-94-LLCN-FFFFF. Copies of materials 
    relevant to this proposed rulemaking are located in the docket at the 
    address listed above. The docket is open from 9 am to 4 pm, Monday 
    through Friday, excluding Federal holidays. The public must make an 
    appointment to review docket materials by calling (202) 260-9327. The 
    public may copy 100 pages from the docket at no charge; additional 
    copies are $0.15 per page.
        Requests for a hearing should be addressed to Mr. David Bussard at: 
    Characterization and Assessment Division, Office of Solid Waste (5304), 
    U.S. Environmental Protection Agency, 401 M Street, SW., Washington, DC 
    20460.
    
    FOR FURTHER INFORMATION CONTACT: The RCRA/Superfund Hotline, toll-free, 
    at (800) 424-9346 or at (703) 920-9810. The TDD Hotline number is (800) 
    553-7672 (toll-free) or (703) 486-3323 in the Washington, DC 
    metropolitan area. For technical information on the RCRA hazardous 
    waste listings, contact: Wanda Levine, Office of Solid Waste (5304), 
    U.S. Environmental Protection Agency, 401 M Street, SW., Washington, DC 
    20460, (202) 260-7458.
        For technical information on the CERCLA aspects of this rule, 
    contact: Ms. Gerain H. Perry, Response Standards and Criteria Branch, 
    Emergency Response Division (5202G), U.S. Environmental Protection 
    Agency, 401 M Street, SW., Washington, DC 20460, (703) 603-8760.
    
    SUPPLEMENTARY INFORMATION: The contents of the preamble to this 
    proposed rule are listed in the following outline:
    
    I. Background
        A. Statutory and Regulatory Authorities
        B. EPA's Hazardous Waste Listing Determination Policy
    II. Today's Action
        A. Summary of Today's Action
        1. Confidentiality Claims
        2. Summary of Listing Determinations and Deferrals
        3. Request for Comment on the Effect of Enforceable EPA/Industry 
    Agreements on Plausible Mismanagement Analysis and Subsequent 
    Listing Determinations
        B. Dye and Pigment Industries Overview
        C. Description of the Process Wastes Identified in Comparison to 
    those Specified in the Settlement Agreement
        D. Description of Health and Risk Assessments
        E. Waste-Specific Listing Determination Rationales
    III. Waste Minimization
    IV. Applicability of Land Disposal Restrictions Determinations
        A. Request for Comment on the Agency's Approach to the 
    Development of BDAT Treatment Standards
        B. Request for Comment on the Agency's Approach to the Capacity 
    Analyses in the LDR Program
    V. Compliance Dates
        A. Notification
        B. Interim Status and Permitted Facilities
    VI. State Authority
        A. Applicability of Rule in Authorized States
        B. Effect on State Authorizations
    VII. CERCLA Designation and Reportable Quantities
    VIII. Economic Impact Analysis
    IX. Executive Order 12866
    X. Regulatory Flexibility Act
    XI. Paperwork Reduction Act
    
    I. Background
    
    A. Statutory and Regulatory Authorities
    
        These regulations are proposed under the authority of Sections 
    2002(a) and 3001(b) and 3001(e)(2) of the Solid Waste Disposal Act, 42 
    U.S.C. 6912(a), and 6921(b) and (e)(2), as amended by the Hazardous and 
    Solid Waste Amendments of 1984 (HSWA). These statutes commonly are 
    referred to as the Resource Conservation and Recovery Act (RCRA) and 
    are codified at Volume 42 of the United States Code (U.S.C.), sections 
    6901 to 6992(k) (42 U.S.C. 6901-6992(k)).
        Section 102(a) of the Comprehensive Environmental Response, 
    Compensation, and Liability Act of 1980 (CERCLA), 42 U.S.C. 9602(a) is 
    the authority for the CERCLA aspects of this rule.
        Section 3001(a) of RCRA, 42 U.S.C. 6921(a), requires EPA to 
    promulgate criteria for identifying characteristics of hazardous wastes 
    and for listing hazardous wastes. Section 3001(b) of RCRA requires EPA 
    to promulgate regulations, based on these criteria, identifying and 
    listing hazardous wastes which shall be subject to the requirements of 
    the Act.
        Hazardous waste is defined at Section 1004(5) of RCRA, 42 U.S.C. 
    6903(5). There are two types of hazardous waste. First, hazardous 
    wastes are those solid wastes which may cause or significantly 
    contribute to an increase in mortality, serious irreversible illness, 
    or incapacitating reversible illness. In addition, hazardous wastes are 
    those solid wastes which may pose a substantial present or potential 
    hazard to human health or the environment when improperly managed.
        EPA's regulations establishing criteria for listing hazardous 
    wastes are codified at Title 40 of the Code of Federal Regulations 
    (CFR) Sec. 261.11 (40 CFR 261.11). Section 261.11 states three criteria 
    for identifying characteristics and for listing wastes as hazardous.
        First, wastes may be classified as ``characteristic'' wastes if 
    they have the properties described at 40 CFR 261.21-24 which would 
    cause them to be classified as having the characteristics of 
    ignitability, corrosivity, reactivity or toxicity.
        Second, wastes may be classified as acutely hazardous if they are 
    fatal to humans at low doses, lethal in animal studies at particular 
    doses designated in the regulation, or otherwise capable of causing or 
    significantly contributing to an increase in serious illness.
        Third, wastes may be listed as hazardous if they contain hazardous 
    constituents identified in Appendix VIII of 40 CFR part 261 and the 
    Agency concludes, after considering eleven factors enumerated in 40 CFR 
    261.11(a)(3), that the waste is capable of posing a substantial present 
    or potential hazard to human health or the environment when improperly 
    managed. Such wastes are designated as toxic wastes. A substance is 
    listed in Appendix VIII if it has been shown in scientific studies to 
    have toxic, carcinogenic, mutagenic, or teratogenic effects on humans 
    or other life forms.
        Wastes listed as hazardous are subject to federal requirements 
    under RCRA for persons who generate, transport, treat, store or dispose 
    of such waste. Facilities that must meet the hazardous waste management 
    requirements, including the need to obtain permits to operate, commonly 
    are referred to as Subtitle C facilities. Subtitle C is Congress' 
    original statutory designation for that part of RCRA that directs EPA 
    to issue those regulations for hazardous wastes as may be necessary to 
    protect human health or the environment. Thus, facilities like 
    incinerators or landfills that are required to comply with RCRA 
    requirements for hazardous waste are referred to as Subtitle C 
    incinerators or landfills.
        Subtitle C is codified as Subchapter III of Chapter 82 (Solid Waste 
    Disposal) of Volume 42 of the United States Code (42 U.S.C. 6921 
    through 6939(e)). EPA standards and procedural regulations implementing 
    Subtitle C are found generally at 40 CFR parts 260 through 272.
        Solid wastes that are not hazardous wastes may be disposed of at 
    facilities that are overseen by state and local governments. These are 
    the so-called Subtitle D facilities. Subtitle D is Congress' original 
    statutory designation for that part of RCRA that deals with federal 
    assistance to state and regional planning efforts for disposal of solid 
    waste.
        Subtitle D is codified as Subchapter IV of Chapter 82 (Solid Waste 
    Disposal) of Volume 42 of the United States Code (42 U.S.C. 6941 
    through 6949(a)). EPA regulations affecting Subtitle D facilities are 
    found generally at 40 CFR parts 240 thru 247, and 255 thru 258.
        Section 3001(e)(2) of RCRA (42 U.S.C. 6921(e)(2)) requires EPA to 
    determine whether to list as hazardous wastes generated by various 
    chemical production processes, including the production of dyes and 
    pigments.
        In June of 1991, EPA entered into a proposed consent decree in a 
    lawsuit filed by the Environmental Defense Fund, et al. (EDF v. Reilly, 
    Civ. No. 89-0598 (D.D.C.), hereinafter referred to as the settlement 
    agreement), in which the Agency agreed to publish a proposed 
    determination as to whether or not to list as hazardous certain wastes 
    from the production of dyes and pigments by November 30, 1994 and to 
    promulgate a final decision by November 30, 1995.
        There are three major classes of dyes and pigments: Azo/benzidine, 
    anthraquinone, and triarylmethane. The settlement agreement specifies 
    that the listing is to address the azo, monoazo, diazo, triazo, 
    polyazo, azoic, and benzidine categories of the azo/benzidine dye and 
    pigment class; the anthraquinone and perylene categories of the 
    anthraquinone dye and pigment class; and the triarylmethane, 
    triphenylmethane, and pyrazolone categories of the triarylmethane dye 
    and pigment class. The settlement agreement also specifies that the 
    listing is to address the following types of wastes where they are 
    found: spent catalysts, reactor still overheads, vacuum system 
    condensate, process waters, spent adsorbent, equipment cleaning sludge, 
    product mother liquor, product standardization filter cake, dust 
    collector filter fines, recovery still bottoms, treated wastewater 
    effluent, and wastewater treatment sludge.
        As part of its regulations implementing Section 3001(e) of RCRA, 
    EPA published a list of hazardous wastes that includes hazardous wastes 
    generated from non-specific sources and a list of hazardous wastes from 
    specific sources. These lists have been amended several times, and are 
    published in 40 CFR 261.31 and 40 CFR 261.32, respectively. In this 
    action, EPA is proposing to amend 40 CFR 261.32 to add five wastes from 
    specific sources generated during the production of dyes and pigments.
        Those hazardous constituents that are proposed to be included in 
    Appendix VII to part 261, Basis for Listing Hazardous Waste, also are 
    proposed to be added to Appendix VIII of Part 261, the list of 
    Hazardous Constituents, if not already included in this list.
        All hazardous wastes listed under RCRA and codified in 40 CFR 
    261.31 through 261.33, as well as any solid waste that exhibits one or 
    more of the characteristics of a RCRA hazardous waste (as defined in 40 
    CFR 261.21 through 261.24), are also hazardous substances under the 
    Comprehensive Environmental Response, Compensation, and Liability Act 
    of 1980 (CERCLA), as amended. See CERCLA Section 101(14)(C). CERCLA 
    hazardous substances are listed in Table 302.4 at 40 CFR 302.4 along 
    with their reportable quantities (RQs). Accordingly, the Agency is 
    proposing to list the proposed wastes in this action as CERCLA 
    hazardous substances in Table 302.4 of 40 CFR 302.4. EPA is not taking 
    action at this time to adjust the one-pound statutory RQs for these 
    substances.
    
    B. EPA's Hazardous Waste Listing Determination Policy
    
        EPA believes that it should provide the public with a better 
    understanding of the basis for EPA's listing decisions. Accordingly, 
    EPA presents here the general approach the Agency uses for determining 
    whether to list a waste as hazardous pursuant to 40 CFR 261.11(a)(3). 
    This presentation focuses on selection of waste management scenarios 
    used in assessing risk and the use of information on risk levels in 
    making listing determinations. These elements are an important part of 
    EPA's general listing policy and critical aspects to the dyes and 
    pigments listing determination. It is important to note that this 
    discussion presents EPA's general listing policy and is not a 
    rulemaking. The Agency may take action at variance with this general 
    policy. The Agency is seeking comment on its policy in order to get 
    input from the public, not in order to promulgate binding rules for 
    listing determinations. The Agency will review any comments received 
    and may revise its policy based on such comments. However, the Agency 
    does not intend to respond to comments submitted.
        The listing criteria described here focus on several aspects of the 
    Agency's listing determination process. The discussion is not intended 
    to cover all potential aspects of these determinations. For example, 
    analyzing population risk is not included in this presentation. The 
    Agency solicits comment on how population risks could be included as a 
    factor in listing determinations. The Agency's approach to calculating 
    distributions of individual risk values when determining ``high end'' 
    risk and the Agency's position on how far into the future it will 
    consider risk are not covered in today's notice. The Agency solicits 
    comment on these factors and their use in listing determinations.
        Currently, risk levels (including carcinogen risk, non-carcinogen 
    risk as determined by hazard quotient (HQ), and ecological risk) 
    provide one of the principal bases for a listing determination. 
    However, risk levels themselves do not represent the sole basis for a 
    listing. Other factors generally are weighed in making a listing 
    decision. The Agency's listing decision policy uses a ``weight-of-
    evidence'' approach in which calculated risk information is a key 
    factor. Available risk values are assessed with all other data 
    available to determine whether a waste is or is not a hazardous waste.
        The criteria for listing wastes as hazardous are described in 40 
    CFR 261.11. They are presented in two basic parts: Numeric criteria for 
    acutely hazardous wastes (defined by 40 CFR 261.11(a)(2)); and criteria 
    for toxic wastes (defined by 40 CFR 261.11(a)(3)) containing toxic 
    constituents listed in Appendix VIII to Part 261 (where 11 factors are 
    considered in determining ``substantial present or potential hazard to 
    human health and the environment'').
        Of these 11 factors, seven deal with risk (constituent toxicity, 
    concentration, waste quantity, migration potential, persistence, 
    degradation product potential, and bioaccumulation potential) and are 
    integrated into the risk values generated. The other four factors 
    (plausible management, damage cases, coverage of other regulatory 
    programs, and other factors as may be appropriate) are individual 
    factors that also are considered in a listing determination. Waste 
    quantity (specifically, ``de minimis'' amounts of waste) also can be a 
    special consideration in making a listing determination for a lower 
    volume wastestream.
    1. Selection of Waste Management Scenarios (261.11(a)(3)(vii))
        As noted above, one of the many factors that the Agency takes into 
    account is the ``plausible types of improper management to which the 
    waste could be subjected.'' 40 CFR 261.11(a)(3)(vii). Exposures to 
    wastes (and therefore the risks involved) will vary by waste management 
    practice.
        It is important to note that a management scenario need not be in 
    use currently to be considered plausible by EPA since disposal 
    practices can and do change over time. Potential future waste 
    management practices are projected and considered in the risk analysis, 
    if appropriate. The Agency often projects risks from management that 
    reasonably could be employed.
        a. Factors for Projecting a Plausible Waste Management Scenario. 
    There are a number of disposal scenarios for wastes not hazardous under 
    RCRA that are common across industries. These include municipal and 
    industrial unlined landfills for solid materials, tanks and unlined 
    surface impoundments for liquids, and boilers for organic solids and 
    liquids. The Agency will presume that these scenarios are plausible 
    unless circumstances unique to a particular industry show that one or 
    more is not plausible for that industry.
        The Agency notes that there may exist certain disposal scenarios 
    not common across industries that could present a greater risk than the 
    risk from the common plausible management scenarios mentioned above. An 
    example might be land-spreading sludge from wastewater treatment 
    facilities. These less common scenarios generally will be considered 
    plausible only when information on an industry indicates that these 
    disposal methods currently are being practiced, or there is good reason 
    to believe they might be practiced in the future.
        In determining whether one of the common disposal scenarios is not 
    plausible, the Agency will consider factors such as the following:
         Availability of waste management practices.
        There may be practical constraints to the type of waste management 
    practices available to a category of waste generators. For example, if 
    facilities in an industry have only a limited amount of land available 
    to them, then building large surface impoundments to handle wastewaters 
    may be highly unlikely and would not be considered plausible.
         Coverage of the Characterization Program.
        Where all, or at least a large percentage, of facilities in an 
    industrial category can be characterized with respect to waste 
    management practices, the Agency may be able to do a more refined 
    analysis of the plausibility of facilities switching from their current 
    waste management practice to a higher risk waste management practice. 
    The Agency may determine it more appropriate to estimate risk based on 
    current management practices where our analysis shows that it is 
    unlikely that facilities would switch to another management practice.
         Effect of Other Regulatory Programs.
        Other regulatory programs, for example, the water pollution control 
    program or air pollution regulatory requirements, can impose legal, 
    technical, or practical restraints on waste management practices. If 
    these requirements restrict certain practices (e.g., water treatment 
    requirements technically and practically might preclude treatment in 
    surface impoundments) the Agency can use this information to consider 
    eliminating that disposal practice from consideration.
         Management Costs.
        Often, the cost of different management scenarios can be a 
    determinative factor in dictating the plausibility of waste management 
    scenarios. In the absence of other potential cost factors, such as 
    liability, the plausibility that a facility would choose a waste 
    management scenario increases as the expense of that management 
    practice decreases. Conversely, it is more implausible to assume that a 
    firm would chose management activities that impose a higher cost (where 
    cost includes the likelihood of future potential liabilities.) Cost can 
    be a consideration the Agency uses in choosing which management 
    scenario to project as a scenario to analyze for determining potential 
    risk of waste management.
        These factors are presented as examples; there may be others 
    appropriate to specific industries. In characterizing the risks for a 
    wastestream where more than one disposal scenario is plausible, the 
    Agency will use the results of the risk assessment for the plausible 
    scenario that presents the highest risks.
        Note that EPA considers the extent to which the plausible 
    management scenario calculated to cause the highest risk is practiced, 
    or could be practiced. Management practices the Agency believes 
    probably would occur infrequently may be less determinative in the 
    final listing determination process. As the probability that generators 
    would use a management practice increases, the greater the weight that 
    set of risk values has in the final listing determination.
    2. Risk Levels in Making Listing Decisions
        As noted earlier, the Agency's listing determination policy 
    utilizes a ``weight-of-evidence'' approach in which risk is a key 
    factor. Risk measurements used include carcinogen risk, non-carcinogen 
    risk as determined by hazard quotient (HQ), and ecological risk. 
    However, risk levels themselves do not necessarily represent the sole 
    basis for a listing. There can be uncertainty in calculated risk values 
    and so other factors are considered in conjuction with risk in making a 
    listing decision.
        a. Use of Risk Levels in a Listing Decision. EPA's current listing 
    determination procedure (illustrated in Figure 1) uses as an initial 
    cancer-risk ``level of concern'' a calculated risk level of 1  x  
    10-5 (one in one hundred thousand) and/or HQs (and/or 
    environmental risk quotients [EQs]) of 1 at any one point in time. Note 
    that individual risks can occur at different points in time. For 
    example, a category of wastestream that is both burned in a boiler by 
    one facility but placed in a landfill by another would be projected to 
    cause exposure through both the air and the drinking water pathways. It 
    is likely that risks from each source will occur at different times, 
    since air exposures would probably occur sooner than groundwater 
    exposures. The Agency will take the timing factor into account when 
    analyzing risk. In accordance with EPA policy, risks from individual 
    carcinogens generally are added together. Listing decisions from this 
    risk level of concern generally will be as follows.
    
    BILLING CODE 6560-50-P
    
    TP22DE94.000
    
    
    BILLING CODE 6560-50-C
        (1) Wastestreams for which the calculated high-end individual 
    cancer-risk level is 1  x  10-5 or higher generally are considered 
    initial candidates for a list decision.
        (2) Wastestreams for which these risks are calculated to be 1  x  
    10-4 or higher, or 1 or higher HQs or EQs for any individual non-
    carcinogen, or non-carcinogens that elicit adverse effects on the same 
    target organ, generally will be considered to pose a substantial 
    present or potential hazard to human health and the environment and 
    generally will be listed as hazardous waste. Such wastestreams fall 
    into a category presumptively assumed to pose sufficient risk to 
    require their listing as hazardous waste. However, even for these 
    wastestreams there can in some cases be factors which could mitigate 
    the high hazard presumption. These additional factors, explained below, 
    also will be considered by the Agency in making a final determination.
        (3) Wastestreams for which the calculated high-end individual 
    cancer-risk level is lower than 1  x  10-5 generally are 
    considered initial candidates for a no-list decision.
        (4) Wastestreams for which these risks are calculated to be 1  x  
    10-6 or lower, and lower than 1.0 HQs or EQs for any non-
    carcinogens, generally will be considered not to pose a substantial 
    present or potential hazard to human health and the environment and 
    generally will not be listed as hazardous waste. Such wastestreams fall 
    into a category presumptively assumed not to pose sufficient risk as to 
    require their listing as hazardous waste. However, even for these 
    wastestreams, in some cases, there can be factors that could mitigate 
    the low hazard presumption. These also will be considered by the Agency 
    in making a final determination.
        (5) Wastestreams where the calculated high-end individual cancer-
    risk level is between 1 x 10-4 and 1 x 10-6 fall in the 
    category for which there is a presumption of candidacy for either 
    listing (risk >10-5) or no listing (risk <>-5). However, 
    this presumption is not as strong as when risks are outside this range. 
    Therefore, listing determinations for wastestreams falling into this 
    range would always involve assessment of the additional factors 
    discussed below.
        b. Additional Factors.
        The following factors will be considered in making listing 
    determinations, particularly for wastes falling into the risk range 
    between 1 x 10-4 and 1 x 10-6:
        (1) Certainty of waste characterization;
        (2) Certainty in risk assessment methodology;
        (3) Coverage by other regulatory programs;
        (4) Waste volume;
        (5) Evidence of co-occurrence;
        (6) Damage cases showing actual impact to human health or the 
    environment; and
        (7) Presence of toxicant(s) of unknown or unquantifiable risk.
    (1) Certainty of Waste Characterization
        EPA compiles data on the amounts and composition of each 
    wastestream. Different sources of variability in these data, 
    variability between facilities, between production processes, between 
    samples, and in analytical methodologies, exist. All such variability 
    sources may influence the Agency's decision on how much weight to place 
    on data collected as a basis for a listing decision.
        Budget constraints or sample availability constraints may limit the 
    size of the database for any one wastestream. In such cases, the Agency 
    generally assumes that the sample(s) taken are representative of each 
    like wastestream from that category of generator and that the data, 
    generated following a QA/QC plan, are ``good'' data. However, EPA will 
    take uncertainty of the data into account in the listing process.
        The Agency sometimes relies on analytical measurements that fall 
    below the level of an analyst's ability to quantify with certainty the 
    concentration of the constituent involved (these measurements are 
    referred to as ``estimated'' or ``J-values'' in listing 
    determinations). Analytical methods used by the Agency have been 
    developed with a goal of obtaining quantitative measurements (i.e., 
    25% uncertainty or less) at levels of regulatory concern. 
    Frequently, analytical measurements may detect the presence of 
    constituents of concern at levels at or below the analytical method's 
    limit of quantitation. However, for some highly toxic substances 
    measurements of constituents below the limit of quantitation may be of 
    toxicological significance and, therefore, potential regulatory 
    significance.
        The limit of quantitation is defined as the level above which 
    results may be obtained with a specified degree of confidence. In the 
    case of methods which use mass spectrometric measurements, quantitative 
    uncertainty is assigned to measurements below the limit of quantitation 
    (although a positive determination of presence is certain) as follows:
         The uncertainty of measurements at the limit of detection 
    (3 times the standard deviation estimation []) approaches 
    100% (33).
         At the point of reliable detection 
    (63), the uncertainty of measurement 
    approaches 50%.
         In the area of accurate quantitation (10 to 
    12), uncertainty approaches 30% to 
    25%, based on the 99% confidence level of the measurement 
    uncertainty.
        In other words, when the analyte signal is 10 or more times larger 
    than the standard deviation of the measurements, there is a 99% 
    probability that the true concentration of the analyte is 
    30% of the calculated concentration.\1\
    ---------------------------------------------------------------------------
    
        \1\Keith, L.H., Environmental Sampling and Analysis: A Practical 
    Guide (Chelsea, MI: Lewis Publishers, 1992). See Figure 12, page 
    110, for the relationship of limit of detection, reliable detection 
    limit, and limit of quantitation.
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        Although the uncertainty of analytical measurements increases as 
    the limit of detection is approached, the calculated concentrations 
    obtained may represent the best available measurement of the analyte 
    present.
        It is the Agency's policy on listing determinations that 
    measurements in the range below the level of quantification but above 
    the level of detection will be used at the reported quantitation level 
    for risk analysis purposes. However, the Agency generally will consider 
    the uncertainty associated with measurements below the quantitation 
    level and assess the impact of that level of uncertainty on a listing 
    decision. Increasing uncertainty of a measurement may increase the 
    importance of other factors in making a listing determination.
    (2) Certainty in Risk Assessment Methodology
        Uncertainty can exist in the methodologies and data used to conduct 
    both the toxicity assessments and the fate and transport exposure 
    models employed in risk assessments. Toxicity assessment methods 
    sometimes rely on animal or cellular models to predict a chemical's 
    effect on humans or animals. Direct toxicity testing of a chemical is 
    not always available. For some of these chemicals, structure/activity 
    relationships can be used to predict the toxicity of the substance 
    involved. In these cases, the Agency considers what degree of 
    uncertainty can exist in that analysis when making listing 
    determinations. Similarly, some fate/transport models make use of an 
    increased amount of input data or can involve actual verification. For 
    those models, uncertainty in exposure analysis is decreased. The Agency 
    weighs the relative uncertainty of the predictive models when 
    generating risk assessments and making listing determinations.
    (3) Coverage by Other Regulatory Programs
        Listing decisions can be strongly influenced by the effect of other 
    regulatory requirements on the wastestreams involved. Where another 
    Federal or State program or other RCRA requirements clearly will 
    provide the type of control needed to eliminate the risk associated 
    with a certain type of waste management, a RCRA listing may be 
    considered unnecessary or redundant.
         Other Federal or State programs.
        If other Federal or State programs clearly regulate risk associated 
    with the wastestream, listing may not be necessary to eliminate risk. 
    For example, if the Office of Air and Radiation within EPA has issued 
    an NESHAP to control emissions of a constituent, it may be unnecessary 
    to consider risk from inhalation of that constituent in making listing 
    determinations. In some cases, another regulatory program may be in the 
    process of developing such regulatory requirements. If this program is 
    under statutory requirements or Court Order, EPA may consider these 
    regulatory requirements to be forthcoming and, in some cases, may defer 
    to them in listing determinations, even where such regulatory coverage 
    is several years away. If this program is under no statutory or legal 
    deadline, no deference typically will be given to projected future 
    regulatory coverage from other programs.
    (4) Waste Volume
        Waste volume is, in fact, part of a risk-level calculation. Risk is 
    projected based on the volume of waste involved. However, volume of 
    waste is also a factor EPA may consider when the projected risk falls 
    in a marginal risk range.
    (5) Evidence of Co-occurrence
        Virtually all wastestreams EPA assesses are complex mixtures of 
    constituents. Where possible, the Agency calculates potential risk for 
    all measured pollutants. Where more than one risk value for 
    carcinogenicity is calculated, concern about overall wastestream 
    effects increases and the Agency will consider that risk additive. 
    However, where sampling and analysis data show compelling evidence that 
    the constituents cannot or do not occur together in the wastestream or 
    at the receptor, the Agency generally will only consider the risk 
    associated with individual constituents.
    (6) Damage Cases
        For each listing determination, EPA seeks data on damage cases. 
    These are cases in which some prior waste management practice has 
    resulted in environmental harm. Where there has been a clear case of 
    harm, the data suggest the management of that waste has already damaged 
    human health or the environment in some way, and that such damage could 
    occur again. Depending on the number and severity of the damage cases 
    and the potential for these damages to happen again, adverse damage 
    cases may provide a ``stand alone'' reason for listing the waste.
        Where damage cases appear to contradict the risk analysis, EPA will 
    try to determine the reason and use that assessment in the overall 
    listing decision.
    (7) Unknown or Unquantified Risk
        Not all constituents in a complex wastestream can be analyzed for 
    risk. Hazard data may not be available either directly or through 
    mechanisms such as structure/activity relationships, or they may be in 
    a form which is not considered usable by EPA. In the cases where some 
    constituents are present but no risk levels can be assigned to them, 
    the Agency considers the potential for these constituents to be 
    hazardous.
        As stated above, use of these additional factors is not limited to 
    cases in which the risk levels fall between 10-4 and 10-6. 
    Pursuant to EPA's listing determination policy ``weight-of-evidence'' 
    approach, the Agency will consider these factors, as appropriate, even 
    where risk levels fall in the presumptive list or presumptive no-list 
    levels.
    
    II. Today's Action
    
    A. Summary of Today's Action
    
    1. Confidentiality Claims
        The hazardous waste listings proposed here are based in part upon 
    data claimed as confidential by certain dye and pigment manufacturers. 
    Although EPA intends to publish information derived from these data 
    claimed as confidential (to the extent relevant to the proposed 
    listing), the Agency is unable to do so at the present time. Therefore, 
    this proposed rule is being published without some of the information 
    that supports the Agency's proposal. Where that information is missing 
    from text, it is noted in the text. Whenever EPA is unable to include 
    pertinent data in a table, the following statement appears in a 
    footnote: ``Relevant data are not included at the present time due to 
    business confidentiality concerns.'' EPA is pursuing avenues to allow 
    publication of the information, and intends to supplement the public 
    record prior to issuing a final listing.
    2. Summary of Proposed Listing Determinations and Deferrals
        In today's notice, EPA is proposing to add five wastes generated 
    during the production of dyes and pigments to the lists of hazardous 
    wastes in 40 CFR 261.32. A summary of the waste groupings proposed for 
    listing are provided below with their proposed corresponding EPA 
    Hazardous Waste Numbers.
    
    K162  Wastewater treatment sludge from the production of azo pigments.
    K163  Wastewaters from the production of azo pigments.
    K164  Wastewater treatment sludge from the production of azo dyes, 
    excluding FD&C colorants.
    K165  Wastewaters from the production of azo dyes, excluding FD&C 
    colorants.
    K166  Still bottoms or heavy ends from the production of triarylmethane 
    dyes or pigments.
        The Agency has determined that these wastes meet the criteria for 
    listing set out in 40 CFR 261.11. Section II.E. of this preamble 
    presents waste characterization, waste management, and risk assessment 
    data, which are the bases for the Agency's proposal to list or not to 
    list the wastes studied in this rulemaking.
        Upon promulgation of these proposed listings, all wastes meeting 
    the listing descriptions would become hazardous wastes and would 
    require treatment, storage, or disposal at permitted facilities. 
    Residuals from the treatment, storage, or disposal of the wastes 
    included in this proposed listing also would be classified as hazardous 
    wastes pursuant to the ``derived-from'' rule (40 CFR 261.3(c)(2)(i)). 
    For example, ash or other residuals from treatment of the listed wastes 
    would be subject to the hazardous waste regulations. Also, 40 CFR 
    261.3(a)(2)(iv) (the ``mixture'' rule) provides that, with certain 
    limited exceptions, any mixture of a listed waste and a solid waste is 
    itself a RCRA hazardous waste.
        However, when these wastes are recycled as described in 40 CFR 
    261.2(e)(1)(iii) or 261.4(a)(8), they are not solid wastes and are not 
    subject to hazardous waste regulations. For example, if a waste is 
    collected and returned in a closed-loop fashion to the same process, 
    the waste is not regulated. To meet the exemption, the manner in which 
    a material is recycled must meet the three key requirements outlined in 
    the rules and in 50 FR 639 (January 4, 1985): (1) The material must be 
    returned to the original process from which it was generated without 
    first being reclaimed; (2) the production process to which the 
    materials are returned must use raw materials as principal feedstocks; 
    and (3) the material must be returned as a substitute for raw material 
    feedstock in the original production process. (The regulations contain 
    other recycling exclusions as well, but the provisions referenced above 
    are the principal ones most likely to be applicable to the wastes at 
    issue in this proposal.) EPA is proposing to amend Appendix VII and 
    Appendix VIII to 40 CFR part 261 to add constituents contained in the 
    above wastestreams which were found to pose risk.
        The Agency requests comments on the proposed listing of the above 
    wastes, and on the option of not listing these wastes.
        This action also proposes not to list as hazardous six wastestreams 
    generated during the production of dyes and pigments:
         Wastewaters from the production of triarylmethane dyes and 
    pigments (excluding triarylmethane pigments using aniline as a 
    feedstock).
         Wastewater treatment sludge from the production of 
    triarylmethane pigments using aniline as a feedstock.
         Wastewaters from the production of triarylmethane pigments 
    using aniline as a feedstock.
         Wastewaters from the production of anthraquinone dyes and 
    pigments.
         Wastewaters from the production of FD&C colorants.
         Dusts and dust collector fines from the manufacture of 
    dyes and pigments.
        The Agency requests comments on the proposal not to list the above 
    wastes and on the option of listing these wastes.
        Because the Agency does not have sufficient sampling information on 
    which to base a proposed listing determination, the Agency proposes to 
    defer a determination of whether to list wastewater treatment sludge 
    from the production of triarylmethane dyes and pigments (excluding 
    triarylmethane pigments using aniline as a feedstock), as well as spent 
    filter aids, diatomaceous earth, or adsorbents from azo, anthraquinone, 
    or triarylmethane dyes, pigments, or FD&C colorants. The Agency intends 
    to obtain such sampling information and issue a supplemental notice 
    making a proposed determination on whether to list the wastes as 
    hazardous. The Agency also is deferring a proposed listing 
    determination for wastewater treatment sludge from the production of 
    anthraquinone dyes and pigments due to lack of health effects 
    information on two constituents, leucoquinizarine and 1-
    aminoanthraquinone, that were found in the wastestream. The Agency 
    requests any information that commenters may have on the toxicology of 
    these constituents, including the existence of any toxic analogs for 
    leucoquinizarine and 1-aminoanthraquinone. EPA will evaluate carefully 
    all public comments and information received in response to this 
    notice. Particular notice will be paid to any data which tend to 
    support or refute a finding of risk to human health and the 
    environment. Based on comments received, EPA may choose, rather than 
    deferring, to promulgate a final determination to either list or not 
    list wastewater treatment sludge from the production of anthraquinone 
    dyes and pigments as hazardous under RCRA.
        The Agency also requests comments on the data used in this 
    proposal, the methodology and assumptions used in the risk assessment, 
    the waste groupings chosen by the Agency and other analyses supporting 
    the proposed listings.
    3. Request for Comment on the Effect of Enforceable EPA/Industry 
    Agreements on Plausible Mismanagement Analysis and Subsequent Listing 
    Determinations
        The Agency is interested in innovative ways of conducting listing 
    determinations that could assure environmental protection with less 
    cost than full regulation as a hazardous waste. One approach on which 
    the Agency seeks comment involves enforceable agreements between EPA 
    and the regulated community.
        The Agency is seeking comment on whether enforceable agreements 
    between EPA and industry that restrict the use of certain waste 
    management practices could affect the Agency's plausible mismanagement 
    analysis and, in turn, affect the Agency's listing determination. 
    Specifically, the Agency seeks comment on whether EPA should pursue 
    such agreements with respect to either the dye and pigment wastes that 
    the Agency is proposing to list in this notice (or, additionally those 
    it proposes not to list). The Agency seeks comment on whether the 
    Agency should decide not to list such wastes (or retain a no-list 
    decision) if the agreements ensure that the wastes will not be managed 
    in a manner that poses unacceptable risk.
        A decision not to list based on such enforceable agreements could 
    be based on the view that management practices that are prohibited in 
    an enforceable agreement are not ``plausible'' because facilities 
    within an industry covered by an enforceable agreement are unlikely to 
    violate that agreement; i.e., use a risky management practice, 
    especially if the agreement were to contain monetary or other sanctions 
    for a breach or violation. Waste management practices that are not 
    plausible because they are prohibited by such an agreement arguably 
    need not be considered by the Agency in determining whether the waste 
    poses ``a substantial present or potential hazard to human health or 
    the environment when improperly treated, stored, transported, or 
    disposed of, or otherwise managed.'' (See discussion of selection of 
    waste management scenarios at I.B.1.) Thus, if a waste does not pose an 
    unacceptable risk if managed in accordance with an enforceable 
    agreement, the Agency could determine that the waste should not be 
    listed as hazardous. The Agency requests comment on the use of such an 
    approach as part of the listing determination for wastes generated 
    during the production of dyes and pigments, including those proposed to 
    be listed and/or proposed not to be listed in today's notice.
        For such an approach to be workable, the EPA believes that the 
    following basic principles must apply:
        (1) All of the companies that generate the wastestream at issue 
    must be party to the agreement;
        (2) To ensure that the agreement will adequately deter prohibited 
    waste management practices, the agreement should be enforceable in 
    court and should contain provisions requiring payment of sufficient 
    penalties or damages if the agreement is violated;
        (3) The agreement should eliminate management practices that pose 
    an unacceptable risk;
        (4) The agreement should contain provisions that would account for 
    new entrants; and
        (5) The agreement should promote waste minimization.
        Section 7003 of RCRA may provide EPA with authority under 
    appropriate circumstances to enter into such agreements on consent. 
    Section 7003(a) of RCRA authorizes EPA to issue orders requiring such 
    action as may be necessary upon receipt of evidence that the past or 
    present handling, storage, treatment, transportation, or disposal of 
    any solid waste or hazardous waste may present an imminent and 
    substantial endangerment to human health or the environment. EPA also 
    has the authority to settle claims under RCRA section 7003 by entering 
    into a consent decree or agreement. In addition, the Agency has 
    inherent authority to enter into contracts that are not prohibited by 
    law. See generally, Kern-Limerick, Inc. v. Scurlock, 347 U.S. 110 
    (1954). Such inherent authority also may be available to enter into 
    such agreements.
        EPA believes that such an approach may be feasible for the wastes 
    generated during the production of dyes and pigments because such 
    wastes are generated by a relatively small number of facilities, and 
    the likelihood of expansion in this industry does not appear to be 
    great. Such an approach may not be feasible in an industry with a 
    greater number of facilities or in an industry that is expanding. 
    Additionally, it may not be a valid approach for an industrial sector 
    in which the wastes generated are so hazardous, move off-site in such a 
    fashion, or require such detailed controls that EPA wants the full 
    regulatory controls and civil and criminal authorities that follow from 
    full Subtitle C regulation.
        The Agency requests comments on the feasibility of entering into 
    and enforcing such agreements with industry. The Agency also requests 
    comment on how such agreements would account for entrance into the 
    market of new facilities that generate the waste at issue (e.g., add 
    new elements to the agreement, issue unilateral order under RCRA 
    Section 7003). The Agency also requests comment on alternative 
    innovative approaches to listing determinations.
    
    B. Dye and Pigment Industries Overview
    
        The dye and pigment industries are comprised of three separate 
    industries, represented by three different trade associations. The 
    Color Pigment Manufacturers Association (CPMA) represents pigment 
    manufacturers, the Ecological and Toxicological Association of the 
    Dyestuffs Manufacturing Industry (ETAD) represents dye manufacturers, 
    and the International Association of Color Manufacturers (IACM) 
    represents food, drug, and cosmetic (FD&C) colorants manufacturers.
        Dyes are intensely colored or fluorescent organic substances that 
    impart color to a substrate by selective absorption of light.\2\ When a 
    dye is applied, it penetrates the substrate in a soluble form, after 
    which it may or may not become insoluble. Dyes are retained in the 
    substrate by physical absorption, salt or metal-complex formation, 
    solution, mechanical retention, or by the formation of ionic or 
    covalent chemical bonds.\3\
    ---------------------------------------------------------------------------
    
        \2\``Pigments--A Primer,'' reprinted from American Ink Maker, 
    June 1989, Color Pigment Manufacturers Association.
        \3\Kirk-Othmer Encyclopedia of Chemical Technology--Volume 8, 
    ``Dyes and Dye Intermediates.''
    ---------------------------------------------------------------------------
    
        Dyes are used to color fabrics, leather, paper, ink, lacquers, 
    varnishes, plastics, cosmetics, and some food items. Dye manufacture in 
    the U.S. includes more than 2,000 individual dyes, the majority of 
    which are produced in quantities of less than 50,000 pounds. In 1990, 
    total U.S. dye production was 258 million pounds. In 1991, there were 
    approximately 33 manufacturing plants operated by 20 companies that 
    produce either azo, anthraquinone, or triarylmethane dyes.\4\
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        \4\1992 RCRA Section 3007 Questionnaire Data.
    ---------------------------------------------------------------------------
    
        Pigments possess unique characteristics that distinguish them from 
    dyes and other colorants. Pigments are colored, black, white, or 
    fluorescent particulate organic or inorganic solids, usually insoluble 
    in, and essentially physically and chemically unaffected by, the 
    vehicle or substrate in which they are incorporated. The primary 
    difference between pigments and dyes is that during the application 
    process, pigments are insoluble in the substrate. Pigments also retain 
    a crystalline or particulate structure and impart color by selective 
    absorption or by scattering of light. With dyes, the structure is 
    temporarily altered during the application process, and imparts color 
    only by selective absorption.\5\
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        \5\``Pigments--A Primer,'' reprinted from American Ink Maker, 
    June 1989, Color Pigment Manufacturers Association.
    ---------------------------------------------------------------------------
    
        Pigments are used in a variety of applications; the primary use is 
    in printing inks. There are fewer pigments produced than dyes, though 
    pigment batches are generally larger in size. The U.S. total 1990 
    pigment production volume of approximately 415 million pounds is 
    composed of 300 million pounds of inorganic pigments and 115 million 
    pounds of organic pigments.\6\ In 1991, there were approximately 27 
    domestic manufacturing plants operated by 20 companies\7\ producing 
    organic pigments subject to the settlement agreement.
    ---------------------------------------------------------------------------
    
        \6\CPMA meeting presentation, August, 1991.
        \7\1992 RCRA Section 3007 Questionnaire Data.
    ---------------------------------------------------------------------------
    
        FD&C colorants are dyes and pigments that have been approved by the 
    Food and Drug Administration (FDA) for use in food items, drugs, and/or 
    cosmetics. Typically, FD&C colorants are azo or triarylmethane dyes and 
    are similar or identical to larger-volume dye products not used in 
    food, drugs, and cosmetics. Manufacture of FD&C colorants is identical 
    to that for the corresponding dye or pigment, except that the colorant 
    undergoes additional purification. Each FD&C colorant batch is tested 
    and certified by the FDA. In 1991, there were approximately 7 domestic 
    manufacturing plants operated by 5 companies\8\ producing FD&C 
    colorants subject to the EDF settlement agreement.
    ---------------------------------------------------------------------------
    
        \8\1992 RCRA Section 3007 Questionnaire Data.
    ---------------------------------------------------------------------------
    
        This proposal addresses the three chemical classes of organic dyes 
    and pigments specified in the settlement agreement: azos, 
    anthraquinones, and triarylmethanes.
        Azos are the largest and most versatile chemical class. The various 
    azo chemical structures are readily synthesized, typical product 
    application methods are not complex, and a broad range of colors can be 
    produced with excellent fastness properties. Azo colorants are used in 
    essentially all organic dye applications, including textiles, paper, 
    inks, coatings, plastics, and leather.
        Pyrazolones are a subset of azo dyes and pigments, named for the 
    substituted pyrazolones that are used as coupling agents. The 
    pyrazolone subclass is comprised mainly of yellow, orange, and red azo 
    dyes and pigments.
        Pyrazolone dyes and pigments are used primarily in textiles and 
    plastics, respectively.
        Despite high costs, anthraquinones are an important group of dyes 
    due to superior fastness. They have applications on cotton, cellulose, 
    and synthetic fibers. They have good affinity for the substrate, level 
    dyeing power, and excellent fastness. Anthraquinone pigments are 
    chemically identical to the corresponding dyestuffs and also exhibit 
    high fastness properties. They are used primarily in automotive paints. 
    There are many more anthraquinone dyes than pigments. Most 
    anthraquinone dyes have not been developed into pigments due to 
    technical constraints, as well as competition from less expensive 
    substitutes.
        Perylene pigments, a subset of the anthraquinone chemical class, 
    provide an economical alternative to heavy metal-containing red 
    pigments. Their excellent thermal stability and fastness properties 
    meet the standards for automotive finishes and other high-quality 
    coatings.
        Triarylmethanes are characterized by their brilliancy of hue, 
    intensity of color, and low fastness properties. Triarylmethane dyes 
    typically are used in the textile industry and in the production of 
    pigments. Pigments typically are used in the production of printing and 
    duplicating inks.
    
    C. Description of the Process Wastes Identified in Comparison to Those 
    Specified in the Settlement Agreement
    
        Based on the Agency's study of the dye and pigment industries, EPA 
    has concluded that many of the dye and pigment processes within each of 
    the three chemical classes generate very similar wastestreams. Because 
    of the similarity of wastestreams associated with the manufacture of 
    each class of dye or pigment (i.e., azo, anthraquinone, and 
    triarylmethane), EPA combined closely related wastestreams into ``waste 
    groupings,'' and proposed one hazardous waste listing description and 
    waste code for each of these groupings. Although, given time and 
    resource constraints, EPA was not able to sample wastestreams generated 
    from the production of each distinct product within a particular waste 
    grouping, the sampling data and raw material and process chemistry 
    information that EPA collected support the waste groupings EPA has 
    established.
        The constituents and their concentrations in a waste will 
    determine, in turn, the nature of the toxicity of the waste. EPA is 
    required to consider the nature and toxicity of a waste in making 
    listing determinations pursuant to 40 CFR 261.11. Given that 
    similarities between wastes will result in a similar listing 
    determination pursuant to the factors in EPA's regulations, it is 
    reasonable to group wastes for the purpose of making listing 
    determinations. Further, grouping similar waste matrices (i.e., 
    wastewaters or sludges) will facilitate the development of land 
    disposal treatment standards (see 40 CFR part 268).
        Listing determinations were made on each waste grouping. For 
    example, all wastewaters resulting from the production of azo pigments 
    are proposed to be listed as K163 hazardous wastes. Other wastewater 
    groupings for which listing determinations were made include 
    wastewaters resulting from the production of azo dyes, excluding FD&C 
    colorants (proposed as K165), wastewaters resulting from the production 
    of anthraquinone dyes and pigments, and wastewaters resulting from the 
    production of FD&C colorants.
        In addition, wastewaters generated from the production of 
    triarylmethane dyes and pigments are grouped together under one waste 
    grouping due to the similarity of these wastes, with the exception of 
    wastewaters from the production of triarylmethane pigments using 
    aniline as a feedstock. Wastewaters from the production of 
    triarylmethane pigments using aniline as a feedstock were found to be 
    significantly different in chemical composition from other 
    triarylmethane dye and pigment processes and, therefore, were placed in 
    a separate waste grouping.
        Triarylmethane pigments using aniline as a feedstock are 
    manufactured at two facilities in the country. Only two triarylmethane 
    products are made at each of these facilities and one is used as an 
    intermediate for the second. The process used in manufacturing these 
    pigments is a batch process but is operated throughout the year. Only 
    two primary reactants are used at these facilities, unlike other dye 
    and pigment operations where hundreds of raw materials often are used 
    at one site. As a result, these reactants are present in the wastewater 
    at high concentrations.
        Thus, wastewaters from the production of triarylmethane dyes and 
    pigments were divided into two categories for purposes of making a 
    listing determination: (1) Wastewaters from the production of 
    triarylmethane dyes and pigments, excluding triarylmethane pigments 
    using aniline as a feedstock, and (2) wastewaters from the production 
    of triarylmethane pigments using aniline as a feedstock.
        The wastewater categories include mother liquors generated from 
    product filtration, filter washwaters, equipment and floor cleaning 
    washwaters, break waters, spent scrubber waters, and other process 
    waters. Treated wastewater effluent also is captured by these 
    wastewater groupings. Although EPA did not sample wastewater following 
    treatment, treated wastewater would be expected to contain the same or 
    fewer hazardous constituents and the same or lower concentrations of 
    such constituents than untreated wastewater. Thus, if not listed before 
    treatment, such wastewater is presumed not to meet the Agency's 
    criteria for listing after treatment. Furthermore, any wastewater 
    listed as hazardous before treatment would continue to be regulated as 
    hazardous waste after treatment.
        Wastewater treatment sludges were grouped in a similar manner to 
    wastewaters. Wastewater treatment sludges generated from the dye and 
    pigment industries include any sludges generated during the 
    pretreatment or treatment of dye and pigment wastewaters. This includes 
    pretreatment sludge generated from filtration and precipitation in 
    equalization and neutralization basins, sludges from powdered activated 
    carbon or other adsorbent treatments, and primary and secondary 
    biological treatment sludges. Sludge groupings defined for purposes of 
    listing determinations include wastewater treatment sludge from the 
    production of azo pigments (proposed as K162), wastewater treatment 
    sludge from the production of azo dyes, excluding FD&C colorants 
    (proposed as K164), wastewater treatment sludge from the production of 
    anthraquinone dyes and pigments, wastewater treatment sludge from the 
    production of triarylmethane dyes and pigments, excluding 
    triarylmethane pigments using aniline as a feedstock, and wastewater 
    treatment sludge from the production of triarylmethane pigments using 
    aniline as a feedstock. These groupings are justified because, as was 
    true within the wastewater grouping, the sludges covered by each sludge 
    waste group exhibit similarities in constituent concentrations.
        Distillation bottoms from dye and pigment manufacturing are 
    generated during raw material and solvent recovery operations. The 
    Agency determined that still bottoms from dye and pigment manufacturing 
    are generated only during recovery operations associated with the 
    manufacture of triarylmethane dyes and pigments. Therefore, the 
    following waste grouping was developed to address distillation bottoms 
    from the dye and pigment industries: Still bottoms or heavy ends from 
    the production of triarylmethane dyes or pigments (proposed as K166).
        The Agency grouped spent filter aids, diatomaceous earth, or 
    adsorbents used in the production of azo, anthraquinone, or 
    triarylmethane dyes, pigments, or FD&C colorants into one waste 
    grouping because these wastes all adsorb unreacted raw materials, by-
    products, and impurities and are generated in physically similar forms. 
    Because the constituent composition of these filter aids varies 
    depending on raw materials used, the Agency does not, at this time, 
    have sufficient data to fully characterize this waste grouping. To 
    further support a listing determination on these wastestreams, the 
    Agency intends to collect additional information which will allow 
    assessment of these wastes either as a single waste grouping or, 
    alternatively, as several separate groupings.
        Dusts and dust collector fines are generated primarily during 
    drying, grinding, and blending operations used in manufacturing both 
    dyes and pigments. These wastestreams were grouped because they all are 
    comprised primarily of product dust.
        Product standardization filter cake probably is generated during a 
    final purification step following product standardization. Information 
    obtained during the industry study does not confirm the existence or 
    description of this wastestream. However, filter cakes generated during 
    product purification are comprised of spent filter aids, diatomaceous 
    earth, or other adsorbent, along with product impurities and, 
    therefore, will be characterized with the spent filter aids wastestream 
    described above.
        Information relevant to this discussion is not included at the 
    present time due to business confidentiality concerns.
        Therefore, the Agency is including the spent catalyst wastestreams 
    with the spent filter aids, diatomaceous earth, or adsorbents used in 
    the manufacture of azo, anthraquinone, or triarylmethane dyes, 
    pigments, or FD&C colorants waste group. The Agency did not encounter 
    any traditional catalysts (i.e., chemicals used to enhance a reaction 
    without being consumed) used in dye and pigment manufacturing.
        Vacuum system condensate, reactor still overhead, and equipment 
    cleaning sludge, are not generated in dye and pigment manufacturing.
        The following table summarizes each of the wastestreams identified 
    in the settlement agreement, and describes their coverage in the 
    listing determinations proposed in today's rulemaking:
    
                 Table II-1.--Settlement Agreement Wastestreams             
    ------------------------------------------------------------------------
       Wastestreams identified in the        Coverage in today's proposed   
            settlement agreement                      rulemaking            
    ------------------------------------------------------------------------
    Product mother liquor..............  Addressed as a wastewater for each 
    Process waters                        industry segment, including azo,  
    Treated wastewater effluent           anthraquinone, and triarylmethane 
                                          dyes and pigments (K163, K165).   
    Wastewater treatment sludge........  Addressed as wastewater treatment  
                                          sludge for each industry segment, 
                                          including azo, anthraquinone, and 
                                          triarylmethane dyes and pigments  
                                          (K162, K164).                     
    Recovery still bottoms.............  Still bottoms from triarylmethane  
                                          dyes and pigments (K166).         
    Spent filter aids..................  Addressed for the industries as a  
                                          whole.                            
    Dust collector fines...............  Addressed for the industries as a  
                                          whole.                            
    Product standardization filter cake  Not explicitly generated.          
    Spent catalysts....................  Not explicitly generated but       
                                          included with spent filter aids.  
    Vacuum system condensate...........  Not generated by these industries. 
    Reactor Still Overhead                                                  
    Equipment Cleaning Sludge                                               
    ------------------------------------------------------------------------
    
    D. Description of Health and Risk Assessments
    
        In determining whether waste generated from the production of dyes 
    and pigments meets the criteria for listing a waste as hazardous as set 
    out at 40 CFR 261.11, the Agency evaluated the potential toxicity and 
    intrinsic hazard of constituents present in the wastestreams, the fate 
    and mobility of these chemicals, the likely exposure routes, the 
    current waste management practices, and plausible management practices. 
    A quantitative risk assessment was conducted for those constituents and 
    wastestreams where the available information made such an assessment 
    possible.
    1. Human Health Criteria and Effects
        The Agency uses health-based levels, or HBLs, as a means for 
    evaluating the level of concern of toxic constituents in various media. 
    In the development of HBLs, EPA first must determine exposure levels 
    that are protective of human health and then apply standard exposure 
    assumptions to develop media-specific levels. EPA uses the following 
    hierarchy for evaluating health effects data and health-based standards 
    in establishing chemical-specific HBLS:
        a. Use the Maximum Contaminant Level (MCL) or proposed MCL (PMCL) 
    as the HBL for the ingestion of the constituent in water, when it 
    exists. MCLs are promulgated under the Safe Drinking Water Act (SWDA) 
    of 1974, as amended in 1986, and consider technology and economic 
    feasibility as well as health effects.
        b. Use Agency-verified Reference Doses (RfDs) or Reference 
    Concentrations (RfCs) in calculating HBLs for noncarcinogens and 
    verified carcinogenic slope factors (CSFs) in calculating HBLs for 
    carcinogens. Agency-verified RfDs, RfCs, and CSFs and the bases for 
    these values are presented in the EPA's Integrated Risk Information 
    System (IRIS).
        c. Use RfDs, RfCs, or CSFs that are calculated by standard methods 
    but not verified by the Agency. These values can be found in a number 
    of different types of Agency documents and EPA uses the following 
    hierarchy when reviewing these documents: Health Effects Assessment 
    Summary Tables (HEAST); Human Health Assessment Group for Carcinogens; 
    Health Assessment Summaries (HEAs) and Health and Environmental Effects 
    Profiles (HEEPs); and Health and Environmental Effects Documents 
    (HEEDs).
        d. Use RfDs or CSFs that are calculated by alternative methods, 
    such as surrogate analysis, including structure activity analysis, and 
    toxicity equivalency.
        All HBLs and their bases for this listing determination are 
    provided in a document entitled ``Dye and Pigment Waste Listing Support 
    Health Effects Background Document'' (RTI,1994), which can be found in 
    the RCRA docket for this rule at EPA Headquarters (see ADDRESSES 
    section).
        Acute toxicity data such as lethal doses for the oral and dermal 
    routes and lethal concentrations for the inhalation route also were 
    evaluated for all analytes in the record samples. These data also are 
    presented in the Health Effects Background Document prepared for this 
    rule.
    
    Use of Metabolic Products
    
        There are three compounds commonly identified in the record samples 
    for which EPA has found no reliable health effects data. These 
    compounds are: Acetoacet-o-anisidide (AAOA), acetoacet-o-toluidide 
    (AAOT), and acetoacetanilide (AAA). Because of the lack of health 
    effects data on these compounds, the Agency explored the use of 
    metabolic pathway information to develop toxicologic values. This 
    approach involves the use of health effects information for compounds 
    expected to follow a similar metabolic pathway to those of the three 
    chemicals of concern to estimate toxicity.
        The metabolic pathways for the class of compounds identified as 
    aromatic amines have been extensively studied, and acetylation and N-
    hydroxylation have been identified as initial metabolic reactions of 
    this class of compounds. Using this information, the Agency proposes to 
    use the toxicity of aniline to represent the toxicity of AAA and the 
    toxicity of 2-aminotoluene to represent the toxicity of AAOA and AAOT. 
    The Agency has assumed a direct quantitative relationship between the 
    constituents of concern (i.e., AAOA, AAOT, AAA) and these compounds 
    (i.e., aniline, 2-aminotoluene) that follow a similar metabolic route.
        In humans as much as 60 percent of aniline that is absorbed is 
    oxidized in a dose-dependent manner to give o- and p-aminophenol, the 
    first step in amide formation for this pathway. The metabolites of 
    these products include acetylated arylamines, and are responsible for 
    the toxicity of aniline.
        Acetoacetanilide (AAA) is a structural analog of aniline and the 
    metabolic pathways are expected to be similar. Since the acetyl group 
    is already part of AAA, initial acetylation may be considered complete.
        Because the metabolic conversions occur on a molar basis and the 
    doses in laboratory studies are reported as parts per million, the 
    difference in molecular weight must be considered. Also, since only 60 
    percent of the aniline is expected to be metabolized by the acetylation 
    pathway and AAA is acetylated in its original form, the toxicity of AAA 
    is expected to be proportionally greater than the toxicity of aniline. 
    Therefore, the HBL for AAA is estimated to be 0.003 mg/L as compared to 
    0.006 mg/L for aniline.
        Acetoacet-o-toluidide (AAOT), and acetoacet-o-anisidide (AAOA) are 
    structural analogues of 2-aminotoluene, and the metabolic pathways are 
    expected to be similar to those previously described for aniline. Since 
    the acetyl group is already part of AAOT and AAOA, initial acetylation 
    may be considered complete.
        Because the metabolic conversions occur on a molar basis and the 
    doses in laboratory studies are reported as parts per million, the 
    difference in molecular weight must be considered. Also, since only 25 
    percent of the aminotoluene is expected to be metabolized by the 
    acetylation pathway, and AAOT and AAOA are acetylated in their original 
    forms, their toxicities are expected to be proportionally greater than 
    the toxicity of 2-aminotoluene. Therefore, the HBLs for AAOT and AAOA 
    are estimated to be 0.00004 mg/L and 0.00005 mg/L, respectively, as 
    compared to 0.0001 mg/L for 2-aminotoluene.
        2-Methoxyaniline also has been identified in the azo pigment 
    wastestream. 2-Aminotoluene has been selected as the surrogate for the 
    toxicity of 2-methoxyaniline, because of the structural similarity of 
    the compounds and the similarity of metabolic mechanisms described 
    above. The Agency requests comment on the use of metabolic pathway 
    information to determine health effects, and on alternate approaches.
    
    2. Coeluting Compounds
    
        A number of compounds detected in the wastes generated from dye and 
    pigment manufacture coelute (i.e., overlap) on the Gas Chromatography/
    Mass Spectrometry (GC/MS) curve, making it impossible to confirm the 
    concentration and, in some cases, the presence of the individual 
    coeluting compounds. For example, the three constituents, 2- and 4-
    aminoaniline, and 2-methoxyaniline, coelute on the GC/MS curve. The 
    coelution is such that the presence of 2- and 4-aminoaniline is 
    indistinguishable, yet the presence of 2- methoxyaniline can be 
    verified. This occurs because the curve for 2-methoxyaniline contains 
    an extra peak in addition to the peaks that overlap with 2- and 4-
    aminoaniline. However, the individual contributions to the total 
    concentration found in the waste can not be established.
        Because the contributions from the individual contaminants can not 
    be established, the Agency assumed that any of the three contaminants 
    could be present at 100 percent of the concentration detected. The 
    Agency evaluated all coeluting compounds independently in the risk 
    assessment and used the highest risk calculated for the compounds to 
    ensure the risk was not underestimated.
        However, 2-methoxyaniline is the expected contaminant in wastes 
    generated from facilities that manufacture azo pigments using 
    acetoacet-o-anisidide (AAOA) as a raw material because 2-methoxyaniline 
    is an expected hydrolysis product of AAOA (refer to Section II.E, 
    Wastewater Treatment Sludge from the Production of Azo Pigments, K162, 
    for a discussion on the hydrolysis of AAOA). Therefore, for wastes 
    generated from the manufacture of azo pigments using AAOA as a raw 
    material, the Agency conducted the risk assessment for these coeluting 
    compounds based on toxicity information for 2-methoxyaniline (see 
    discussion of metabolic products, above, and the Dye and Pigment Waste 
    Listing Support Health Effects Background Document for discussions on 
    the toxicity surrogate used for 2-methoxyaniline).
        A second set of coeluting compounds consists of the three isomers 
    2-, 3-, and 4-aminotoluene. The presence of the three isomers was 
    confirmed when detected, and the combined concentration of the three 
    compounds was quantified. Because the contributions from the individual 
    contaminants can not be established, any one of the coeluting 
    contaminants could be present at 100 percent of the concentration 
    detected. Therefore, the Agency evaluated coeluting compounds with 
    health-based levels independently in the risk assessment and used the 
    highest risk calculated by the constituents, in this case 2-
    aminotoluene, to ensure that risk was not underestimated. The volume of 
    2-aminotoluene consumed as a raw material, based on 1991 RCRA Section 
    3007 Questionnaire data, is approximately 9 times that of the other 
    isomers. In addition, aromatic amines with substitutions in the 2- and 
    4- positions of the aromatic ring are used in the manufacture of azo 
    dyes much more frequently than those substituted in the 3- position. 
    Therefore, any impurities or breakdown products from aromatic amines 
    are likely to be substituted in the 2- and 4- positions.
        1,2-diphenylhydrazine and azobenzene also coelute on the GC/MS 
    curve. Both compounds are likely oxidation products of aniline, and may 
    be present in the waste as reaction by-products. In addition to the 
    uncertainty in establishing concentrations for each of the two 
    compounds, the chemical pathway from aniline to these oxidation 
    products suggests that either contaminant may be present at all or part 
    of the concentration detected. The Agency evaluated these coeluting 
    compounds independently and used the highest risk calculated by the 
    compounds to ensure the risk was not underestimated.
        As with azobenzene and 1,2-diphenylhydrazine, diphenylamine and N-
    nitrosodiphenylamine coelute on the GC/MS curve and are likely by-
    products resulting from the oxidation of aniline. As stated above, the 
    Agency evaluated these coeluting compounds independently and used the 
    highest risk calculated by the compounds to ensure the risk was not 
    underestimated.
        The Agency requests comments on the approach used to assess risk 
    when compounds that coelute were detected in the wastestream, and on 
    alternative approaches that commenters may develop.
    
    3. Risk Analysis
    
    Risk Characterization Approach
    
        The risk characterization approach follows the recent EPA Guidance 
    on Risk Characterization (Habicht, 1992) and Guidance for Risk 
    Assessment (EPA Risk Assessment Council, 1991). The guidance specifies 
    that EPA risk assessments will be expected to include (1) the central 
    tendency and high-end portions of the risk distribution, and (2) 
    important subgroups of the populations such as highly susceptible 
    groups or individuals, if known. In addition to the presentation of 
    results, the guidance also specifies that the results portray a 
    reasonable picture of the actual or projected exposures with a 
    discussion of uncertainties. These documents are available in the 
    public docket for this action (see ADDRESSES section).
    
    Individual Risk
    
        Individual risk descriptors are intended to convey information 
    about the risk borne by individuals within a specified population and 
    subpopulations. These risk descriptors are used to answer questions 
    concerning the affected population, and the risk for individuals within 
    a population of interest. The approach used in this analysis for 
    characterizing baseline individual risk included: (1) Identifying and 
    describing the population of concern for an exposure route; (2) 
    determining the sensitivity of the model parameters used in the risk 
    estimation; (3) estimating central tendency and high-end values for the 
    most sensitive parameters in the risk estimation procedures; and (4) 
    calculating individual risk for likely exposure pathways that provides 
    a characterization of the central tendency and high-end risk 
    descriptor.
    
    Risk Assessment
    
        The results of the risk assessment are presented in waste-specific 
    risk tables in each of the basis for listing sections (Section II.E.). 
    The risk tables include the following information: Constituents of 
    concern; estimated human health risk associated with the current and 
    plausible management scenarios; high, low, and average concentrations 
    of constituents found in this wastestream; the number of samples in 
    which the constituent was detected; notes regarding ``J-values'' (see 
    Section II.B on Data Uncertainties); and industry-submitted data.
        In addition to those compounds presented in the waste-specific risk 
    tables, the Agency's characterization data include a number of 
    compounds identified as present in the waste but for which no health 
    benchmarks exist. In addition, other compounds which do have health 
    benchmarks have been identified in these wastes but were dropped from 
    further consideration following the risk screening because the risks 
    were projected to be below levels of concern. The risk tables presented 
    in this preamble do not contain these additional constituents. The 
    complete list of constituents found in each of the wastes generated 
    from the manufacture of dyes and pigments, an explanation of the risk 
    screening process, and an explanation of EPA's development of the 
    target analyte list are presented in the Listing and Health Effects 
    Background Documents for this proposed rule, which are located in the 
    RCRA Docket for this rulemaking (See ADDRESSES section).
        The analysis of risk was developed using both the input of derived 
    or measured toxicological information and the modeling of exposure from 
    baseline (or current) waste management practices and other plausible 
    management scenarios. Pursuant to the Agency's regulations on listing 
    hazardous wastes, EPA considers the ``plausible types of improper 
    management to which the waste could be subjected'', 40 CFR 
    261.11(a)(3)(vii). Thus, plausible management is one of the waste 
    management scenarios used by EPA to assess the risks to human health 
    and the environment from the disposal of the wastes under 
    consideration.
        The choice of ``plausible management'' depends on a combination of 
    factors which are discussed in Section II.A, ``EPA's Listing 
    Determination Process.'' The following discussion explains the 
    plausible management scenarios used to assess risk for each of the 
    waste groups addressed in this proposal. The Agency requests comment on 
    its choice of plausible management scenarios and on the possibility of 
    using alternative plausible management scenarios.
    
    Sludges and Other Solid Materials
    
        The plausible management scenario used to assess risks for the 
    wastewater treatment sludges from the production of azo dyes and 
    pigments (K162 and K164), and still bottoms or heavy ends from the 
    production of triarylmethane dyes and pigments (K166) was disposal in 
    an on-site monofill. Disposal in an on-site monofill for these waste 
    categories results in the highest adverse exposure of sensitive 
    individuals or populations. For wastewater treatment sludges from azo 
    dye production (K164), this plausible management scenario (i.e., on-
    site monofill) currently is practiced.
        The Agency determined that disposal in an on-site monofill is a 
    plausible management scenario for wastewater treatment sludges from azo 
    pigment production (K162) and still bottoms or heavy ends from the 
    production of triarylmethane dyes and pigments (K166), for the 
    following reasons:
         On-site monofills have been used by industry to dispose of 
    wastewater treatment sludge from the manufacture of dyes and pigments;
         Most of the still bottoms generated from the production of 
    triarylmethane dyes and pigments are high-volume wastestreams for which 
    on-site monofills are a plausible management option; and
         On-site monofills can be a lower-cost disposal option.
        Therefore, there is a potential for monofills to be constructed and 
    used in the future, by either dye or pigment manufacturers to dispose 
    of wastewater treatment sludges or other high-volume solid wastes.
        For wastewater treatment sludge from the production of 
    triarylmethane pigments using aniline as a feedstock, the plausible 
    management was determined to be the current management, blending with 
    non-hazardous fuel. Currently, 100% of this waste is sent off-site for 
    non-hazardous fuel blending. The Agency believes that this waste will 
    continue to be managed in this manner because the relatively high 
    organic content of the waste gives the material value as a fuel 
    ingredient. Therefore, generators of the waste have an economic 
    incentive to continue fuel blending. For comparison purposes, the 
    Agency also projected the risks from managing this wastestream in a 
    municipal landfill (from release of contaminants into ground water) and 
    in an on-site boiler (from release of contaminants into the air).
        The primary exposure pathway considered from disposal of solid 
    materials in both unlined municipal landfills (evaluated as the 
    baseline management practice for K162, K164, and K166) and monofills 
    (evaluated as plausible management practices for K162, K164, and K166) 
    is direct ingestion of drinking water from residential wells near the 
    disposal site. Because of the widespread practice of daily cover, 
    indirect air pathways and surface erosion and runoff were not evaluated 
    for municipal landfills. For on-site monofills, however, the 
    presumption of no daily cover was used, and risks associated with 
    indirect pathways were evaluated.
        In addition to estimating potential risks from waste disposed in an 
    unlined municipal landfill, the Agency evaluated risks from municipal 
    landfills meeting the minimum requirements for a Subtitle D landfill 
    (56 FR 50978, 1991). These requirements include daily cover, flexible 
    membrane liner, leachate collection system, clay liner, and final cap 
    and cover. The results of these analyses can be found in the Risk 
    Assessment for Dye and Pigment Waste Listing Determination. This 
    document is available in the RCRA public docket (see ADDRESSES 
    section).
        A dilution factor based on the ratio of the volume of the waste to 
    the volume of co-disposed municipal waste and daily cover was used to 
    estimate the concentrations of the constituents of concern in the 
    landfill. The concentrations of the constituents measured in the waste 
    were multiplied by this dilution factor to determine the concentration 
    of the constituents in the landfill. The concentrations of the 
    constituents in the landfill leachate were estimated using Toxicity 
    Characteristics Leaching Procedure (TCLP) data submitted by industry 
    for selected constituents (3,3'-dichlorobenzidine, aniline, 4- 
    chloroaniline, and 2- and 4-aminotoluene), or when TCLP data were not 
    available, by using a soil-water partitioning equation.
        EPA used the following linear partition equation (Dragan, 1988) 
    with an adjustment to relate sorbed concentration to total waste 
    concentration.
    
    CL = CW/[Foc * Koc + O * S/Bd]
    
    where CL=leachate concentration
    CW=waste concentration
    Foc=fraction organic carbon
    Koc=organic carbon partitioning coefficient
    O=porosity
    S=fraction water content
    Bd=bulk density
    
        The physical properties of the waste used in this equation (i.e., 
    bulk density, fraction organic carbon) were obtained either from the 
    Agency's record samples when available, or from the 1991 RCRA Section 
    3007 Questionnaire responses.
        The volume of leachate and rate of ground-water recharge were 
    estimated using the HELP model. The HELP model uses site-specific 
    precipitation values and standard assumptions for the characteristics 
    of municipal waste to estimate infiltration and recharge rates. For the 
    evaluation of dye and pigment wastes in municipal landfills, annual 
    precipitation rates for sites near all dye and pigment facilities were 
    ranked. Charlotte, North Carolina was selected as representative of the 
    median precipitation value for the areas near dye and pigment 
    facilities, and Charleston, South Carolina, was selected as 
    representative of sites with high annual rainfall potential. The 
    default meteorologic conditions for these locations in the HELP model 
    were used to determine the infiltration and recharge rates used in the 
    ground-water modeling.
        The distance to the receptor wells near the municipal landfill used 
    in the ground-water modeling were obtained from the survey of well 
    distances conducted for the Background Document for EPACML: Finite 
    Source Methodology (EPA, 1992). The value selected as representative of 
    the average condition is the 50th-percentile value for well distance 
    (438 m), and the value for the high-end (close) condition (48 m) is the 
    95th-percentile value.
        The Agency used the MULTIMED groundwater model to simulate the 
    subsurface dilution and attenuation of the leachate constituents in 
    order to estimate the concentration of constituents at the hypothetical 
    residential wells. The Agency then calculated risks to an individual, 
    assuming the residents using this well on average consume 1.4 L/day of 
    contaminated water, or 2 L/day for higher consumptions. Values of 9 or 
    30 years were used for the average and high-exposure duration 
    estimates. The formulae used and a more detailed discussion of the 
    application of these models to the waste samples can be found in the 
    Risk Assessment for Dye and Pigment Waste Listing Determination, 
    available in the RCRA public docket (see ADDRESSES section).
        For on-site monofills, the leaching analysis was the same as for 
    municipal landfills except that the waste concentrations are not 
    diluted in the monofill.
        The distance to the nearest receptor wells near the on-site 
    landfill used in the ground-water modeling were obtained from a 
    telephone survey of 9 city planning offices and a review of site visit 
    reports and site maps. The value selected as representative of the 
    average condition is the 50th-percentile value for well distance (163 
    m) and the value for the high-end (close) condition (16 m) is the 
    closest value. The Risk Assessment for Dye and Pigment Waste Listing 
    Determination for this rulemaking contains a more detailed discussion 
    of these values. This document is available in the RCRA public docket 
    (see ADDRESSES section).
        In addition to direct ingestion of contaminated drinking water, 
    additional pathways were evaluated depending on the characteristics of 
    the waste and management practices evaluated. These pathways included 
    inhalation pathways from airborne particulates and volatiles released 
    from the monofills, and indirect exposure pathways such as the 
    ingestion of vegetables grown in soil contaminated by runoff from the 
    on-site landfill and/or dermal exposure due to direct contact with 
    contaminated soil. The algorithms used for the estimation of risks due 
    to indirect exposures were taken from the Methodology for Assessing 
    Health Risks Associated with Indirect Exposure to Combustion Emissions 
    (U.S. EPA, 1990) as modified by the September 24 draft of Addendum: 
    Methodology for Assessing Health Risks Associated with Indirect 
    Exposure to Combustion Emissions. Working Group Recommendations (U.S. 
    EPA, 1993) and the Risk Assessment Guidance for Superfund (RAGS): 
    Volume I--Human Health Evaluation Manual (Part B, Development of Risk-
    base Preliminary Remediation Goals) (U.S. EPA, 1991), and Dermal 
    Exposure Assessment: Principles and Applications. Interim Report (U.S. 
    EPA 1992) for dermal exposures to water. These documents are available 
    in the public docket for this rule (see ADDRESSES section).
        The air pathways were evaluated using the CHEMDAT 7 air emission 
    model to determine the emission rates for volatile constituents from 
    the landfill, tanks, and storage bins. The Fugitive Dust Model (FDM) 
    was used to determine the emission rates for particulates. These 
    emissions were coupled with dispersion coefficients to determine the 
    ambient air concentrations and the rate of deposition of the waste 
    constituents onto the nearby soil, vegetable gardens, watersheds, and 
    water bodies. The distances to air receptors are assumed to be similar 
    to those used for the ground-water wells. The meteorologic locations 
    used for the air modeling were selected by a procedure similar to that 
    used to select the ground-water locations. The annual average wind 
    speed, temperature, and precipitation values for 34 sites near dye and 
    pigment facilities were evaluated to determine three sites believed to 
    represent a range of conditions to be examined in greater detail. 
    Hourly meteorological data for five years were ranked for these three 
    sites to select the location and year of the data to be used in the air 
    modeling. For the average case, Huntington, West Virginia was selected. 
    For the high-end case, Charlotte, North Carolina was selected.
        An on-site boiler (as the plausible management scenario) also was 
    evaluated for exposure through the air pathway for still bottoms 
    generated from the production of triarylmethane dyes and pigments 
    (K166), and for wastewater treatment sludge from the production of 
    triarylmethane pigments using aniline as a feedstock. The boiler was 
    characterized as a small non-hazardous boiler based upon Agency 
    information and industry-supplied data in the RCRA Section 3007 
    Questionnaire data. The meteorologic data used to characterize the 
    dispersion were determined based upon a distribution of meteorologic 
    data collected for sites near existing dye facilities. These data are 
    ranked by year and location, and the 50th- and 90th-percentile year and 
    location were selected for the central and high-end dispersion 
    modeling. The air dispersion was estimated using the COMPDEP model to 
    estimate air concentrations and wet and dry deposition of the 
    constituents on nearby soil, vegetables and water bodies. The air 
    concentrations and deposition data also were used to evaluate indirect 
    exposures.
    
    Wastewaters
    
        For wastewater streams (K163, K165, and wastewaters from the 
    production of triarylmethane dyes and pigments) the Agency determined 
    that treatment in surface impoundments represents the plausible 
    management scenario because, since surface impoundments currently are 
    in use or planned at several dye facilities, and waste management 
    practices in the dye and pigment industries are generally similar, the 
    Agency believes that pigment manufacturers may employ surface 
    impoundments in the future. In addition, facilities currently 
    manufacturing dyes also could manufacture pigments in the future and 
    manage wastewaters from pigment production in surface impoundments.
        The baseline management practice evaluated for these wastewater 
    streams (i.e., K163, K165, and wastewaters from the production of 
    triarylmethane dyes and pigments) was treatment in tanks. Thus, for 
    wastewaters, the modeling included direct and indirect exposures to 
    volatile emissions from surface impoundments and tanks and direct and 
    indirect exposures to contaminants that may leach into ground water 
    from unlined surface impoundments. The air emissions from tanks were 
    estimated using the CHEMDAT 7 air emission model and the dispersion of 
    these emissions was estimated using the Industrial Source Complex 
    Model-Long Term, Version 2 (ISCLT2) air dispersion model. The 
    meteorologic locations used for estimating the emissions and 
    dispersions were the same locations selected for use with air models 
    for volatile emissions from landfills. Very few inhalation health-based 
    levels are available for constituents found in dye and pigment 
    wastewaters. Risk from direct inhalation exposure to wastes disposed in 
    surface impoundments was estimated to be less than one-in-a-million for 
    all constituents. Results from air emission modeling for tanks are 
    presented in the Risk Assessment Background Document for the Proposed 
    Rule in the RCRA Docket at EPA Headquarters (see ADDRESSES section).
        Since the constituents in these wastes are highly soluble, leaching 
    from unlined impoundments was evaluated. The concentration of the 
    constituents in the leachate was assumed to be equal to the 
    concentration in the wastewater.
        To estimate the concentration of constituents at the hypothetical 
    residential well, the Agency attempted to use the MULTIMED model to 
    simulate the subsurface attenuation and dilution of the surface 
    impoundment leachate. However, there are limitations of the MULTIMED 
    model that preclude its use in this analysis. These include the large 
    volume of leachate estimated to be released from the surface 
    impoundment and a conservative approach to predict the horizontal 
    transport of the leachate within the aquifer. This resulted in an 
    infiltration rate that is so high that it overwhelms the aquifer and 
    dilution was not expected. Therefore, to evaluate risk for those 
    wastewaters that the Agency is proposing to list, the Agency assumed 
    for this proposal that a dilution and attenuation factor (DAF) of 100 
    is achievable during migration to the nearest drinking water well. The 
    Agency's toxicity characteristic (TC) rule (55 FR 11798, 1990) adopts a 
    DAF of 100 to estimate the subsurface fate and transport between an 
    unlined landfill and a receptor drinking water well. For purposes of 
    the risk analyses, the concentrations in the residential wells near the 
    on-site disposal facility were estimated to be equal to 0.01 times the 
    concentrations measured in the wastewater. The residents using this 
    well are assumed on average to consume 1.4 L/day or 2L/day of 
    contaminated water for an exposure duration of 9 years or 30 years.
        The Agency believes that it is more reasonable to use the TC rule 
    approach to support a proposed determination to list, rather than 
    developing a model more sophisticated than the MULTIMED model because 
    the Agency believes a more sophisticated analysis would suggest greater 
    estimated risks than the analysis using a DAF of 100 for the following 
    reasons. First, the DAF of 100 was derived for the TC rule for a range 
    of municipal landfill leachate volumes that are generally lower than 
    leachate volumes from surface impoundments. Surface impoundment DAFs 
    are expected to be lower (and risks subsequently higher) compared to 
    landfill DAFs as a result of both the liquid in the impoundment and 
    subsequent increase in hydraulic head. Second, in the TC analysis, the 
    location of the receptor well was varied anywhere within the extent of 
    the contaminant plume. For listing determinations, the Agency generally 
    assumes that the well is located on the centerline of the plume. This 
    assumption would lead to a lower DAF and higher risks. Thus, because 
    the use of the TC DAF of 100 underestimates risk, use of the TC to 
    estimate risk can support a proposal to list. A more sophisticated 
    model would show only higher risk numbers. The wastewaters that the 
    Agency proposes not to list were evaluated using MULTIMED and creating 
    a bounding estimate. The Agency believes that it is reasonable to use 
    the MULTIMED model to support this proposed determination not to list 
    certain wastewaters because it overestimates risks.
    
    Ecological Risks
    
        In addition to evaluating the risk to human health, the analysis 
    also estimates risks to fish and wildlife from exposure to dye and 
    pigment wastes. The concentrations of contaminants of concern in water 
    bodies near dye and pigment waste facilities were estimated using the 
    indirect exposure methodology and a few high-end input parameters. As a 
    screening analysis, the estimated surface-water concentrations were 
    compared with the National Ambient Water Quality Criteria (NAWQC), or 
    LC50 values for bluegill and/or rainbow trout if NAWQC were not 
    available. The risks to terrestrial and avian species were evaluated by 
    comparing the waste concentration with the oral rat LD50, dermal 
    rabbit LD50, any available avian LD50 values, and if 
    available, a Lowest Observed Adverse Effects Level (LOAEL). Aniline 
    from the manufacture of triarylmethane pigment using aniline as a 
    reactant was the only compound identified as a potential risk to the 
    aquatic or terrestrial environment by this method. Details of these 
    analyses are presented in the Risk Assessment for Dye and Pigment Waste 
    Listing Determination available in the public docket (see ADDRESSES 
    section).
        The Agency requests comments on methodology used by the Agency in 
    selecting plausible mismanagement scenarios and assessing risks and on 
    the plausible management scenarios selected for the wastestreams 
    generated from the manufacture of dyes and pigments.
    
    E. Waste-Specific Listing Determination Rationales
    
    1. Wastes From the Production of Azo Pigments
        a. Wastewater treatment sludge from the production of azo pigments 
    (K162).
    
    Summary
    
        EPA is proposing to list as hazardous wastewater treatment sludges 
    from the production of azo pigments. This wastestream meets the 
    criteria set out at 40 CFR 261.11(a)(3) for listing a waste as 
    hazardous and is capable of posing a substantial present or potential 
    hazard to human health or the environment. Based on ingestion of 
    contaminated ground water, EPA calculated high-end individual cancer-
    risk levels for six hazardous constituents that are equal to or exceed 
    1E-4 for carcinogens or have HQs equal to or greater than 1 for non-
    carcinogens for the plausible management practice, an on-site monofill. 
    The combined carcinogenic risk for multiple co-existing constituents in 
    this wastestream is projected to be 6E-3 for the on-site monofill. In 
    addition, a combined risk of 1E-4 for multiple co-existing contaminants 
    were identified for the baseline management practice, a municipal 
    landfill. Calculated risks exceeding 1E-4 also were identified from 
    exposure to four contaminants through ingestion of contaminated 
    vegetables or through dermal contact with contaminated soil. Three 
    additional contaminants pose calculated individual risks between 1E-4 
    and 1E-6 for the on-site monofill, and 4 contaminants pose calculated 
    risks between these levels for the municipal landfill. Six contaminants 
    pose calculated individual risks between 1E-4 and 1E-6 from exposures 
    through indirect pathways.
    
                  Table II-2.--Waste Characterization and Risk Estimates--K162--Wastewater Treatment Sludge From the Production of Azo Pigments             
    --------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Baseline management            Plausible management                       Waste characterization                
                                     -----------------------------------------------------------------------------------------------------------------------
                                           Municipal landfill***            On-site monofill***                                                             
         Constituents of concern     ---------------------------------------------------------------   Avg.     High     Low                                
                                                                          Central                     conc.    conc.    conc.      # of pts        Notes    
                                      Central tendency     High end       tendency       High end                                                           
    --------------------------------------------------------------------------------------------------------------------------------------------------------
    Aniline.........................  Risk<1e-6 risk="1E-6" risk="1E-5" risk="6E-5" f.n.="" f.n.="" f.n.="" f.n..........="" .............="" 2-="" &="" 4-aminoaniline/="" p2-="" risk="6E-6" risk="3E-5" risk="3E-6" risk="3E-4" 7.17="" .......="" .......="" 1="" of="" 5.......="" j,="" s="" methoxyaniline*.="" 2-="" &="" 4-aminotoluene**...........=""><1e-6><1e-6 risk="1E-5" risk="3E-5" 1.3="" 1.5="" 1.2="" 3="" of="" 8.......="" j(3),="" i(3)="" acetoacet-o-anisidide="" (aaoa)....="" risk="2E-6" risk="8E-6" risk="3E-4" risk="1E-3" 0.67="" .......="" .......="" 1="" of="" 5.......="" s="" acetoacet-o-toluidide="" (aaot)....="" risk="1E-5" risk="6E-5" risk="6E-4" risk="4E-3" f.n.="" f.n.="" 0.31="" 4="" of="" 5.......="" j(1),="" s="" acetoacetanilide="" (aaa)..........="" risk="7E-6" risk="3E-5" risk="1E-4" risk="6E-4" f.n.="" f.n.="" 0.14="" 5="" of="" 5......="" (j)(1),="" s="" 1,3-dinitrobenzene..............="" hq=""><1 hq=""><1 hq="5" hq="7" 1.05="" 1.6="" 0.72="" 3="" of="" 16......="" j(3),="" i(3)="" 3,3'-dimethyl-="" pbenzidine.......=""><1e-6><1e-6 risk="3E-6" risk="1E-5" 1.9="" 2.4="" 1.3="" 2="" of="" 16......="" j(2),="" i(2)="" nitrobenzene....................="" hq=""><1 hq=""><1 hq="10" hq="14" f.n.="" f.n.="" f.n.="" f.n..........="" j="" 2,4-dinitrophenol...............="" hq=""><1 hq=""><1 hq="1" hq="1" 0.74="" .......="" .......="" 1="" of="" 16......="" j="" combined="" carcinogen="" risk........="" risk="3E-5" risk="1E-4" risk="8E-3" risk="6E-3" --------------------------------------------------------------------------------------------------------------------------------------------------------="" *risk="" estimates="" based="" on="" surrogate="" for="" 2-methoxyaniline.="" **risk="" estimates="" based="" on="" 2-aminotoluene.="" ***exposure="" through="" ingestion="" of="" contaminated="" water.="" f.n.="" relevant="" data="" are="" not="" included="" at="" the="" present="" time="" due="" to="" business="" confidentialty="" concerns.="" notes:="" all="" concentrations="" are="" in="" mg/kg.="" j(#)--samples="" where="" estimated="" concentrations="" are="" below="" quantitation="" limits,="" ``(#)''="" indicates="" number="" of="" samples="" that="" are="" ``j''="" values.="" i(#)--includes="" data="" supplied="" by="" industry,="" ``(#)''="" indicates="" number="" of="" samples="" that="" are="" industry-supplied.="" s--toxicity="" estimated="" based="" on="" metabolic="" similarity="" to="" chemical="" analog.="" table="" ii-3.--k162--risk="" values="" for="" disposal="" in="" a="" monofill="" (other="" than="" drinking="" contaminated="" ground="" water)="" ----------------------------------------------------------------------------------------------------------------="" vegetable="" ingestion="" soil="" dermal="" contact="" soil="" ingestion="" constituent="" -----------------------------------------------------------------------------------------="" central="" high="" end="" central="" high="" end="" central="" high="" end="" ----------------------------------------------------------------------------------------------------------------="" 1,3-dinitrobenzene....="" 2-aminoaniline........="" r="4E-5" r="4E-5" 2-aminotoluene........="" r="3E-6" r="2E-5" 4-aminotoluene........="" r="1E-6" r="1E-6" 2,4,6-trichlorophenol.="" r="1E-6" r="2E-6" 3,3'-dichlorobenzidine="" r="2E-3" r="7E-3" r="7E-5" r="2E-4" r="9E-6" r="3E-5" 3,3'-dimethylbenzidine="" r="4E-3" r="5E-3" r="3E-5" r="3E-5" r="5E-6" r="6E-6" acetoacet-o-anisidine.="" r="3E-5" r="3E-5" acetoacet-o-toluidine.="" r="3E-4" r="5E-4" acetoacetanilide......="" r="ER-5" r="2E-4" aniline...............="" r="1E-5" r="1E-5" total="" carcinogen="" risk.="" r="6E-3" r="">9E-3         R=1E-4         R=2E-4         R=1E-5         R=4E-5       
    ----------------------------------------------------------------------------------------------------------------
    
    Discussion
    
        The volume reported by the industry in the 1991 RCRA Section 3007 
    Questionnaire data for wastewater treatment sludge from the manufacture 
    of azo pigments (K162) is not included at the present time due to 
    business confidentiality concerns. Over 99% of this wastestream 
    currently is disposed in Subtitle D municipal landfills. Therefore, the 
    Agency used disposal in a municipal landfill as the baseline management 
    practice. In addition, as explained under Section II.D, Description of 
    Health and Risk Assessments, the Agency evaluated on-site monofilling 
    as a plausible management scenario.
        The projected risks of increased cancer or hazard quotient above 
    one for exposure to this waste are presented in Table II-2. The data 
    presented in this table represent 16 samples collected from 4 azo 
    pigment-manufacturing facilities. Eleven of the 16 samples were 
    collected and analyzed by industry, and were submitted to EPA for 
    evaluation. The 11 industry samples were analyzed using Gas 
    Chromatography/Mass Spectrometry (GC/MS), Method 8270B in EPA's ``Test 
    Methods for Evaluating Solid Waste, Physical/Chemical Methods'' (SW-
    846, Third Edition) but were not analyzed using High Pressure Liquid 
    Chromatography/Thermospray/Mass Spectrometry (HPLC/TS/MS), Method 8321 
    in SW-846. EPA has reviewed the quality of these industry submitted 
    data and has found that these data meet the Agency's data quality 
    objectives and, therefore, qualify for inclusion in the waste 
    assessment. Inclusion of these industry data, however, does bias the 
    industry's characterization toward one facility (i.e., of 16 data 
    points, 11 were submitted by one facility, and 2 were collected by the 
    Agency at that same facility). The five EPA-collected samples, 
    representing four facilities, were analyzed using both methods, a 
    process which encompasses more analytes. Therefore, several analytes, 
    specifically acetoacetanilide (AAA), acetoacet-o-toluidide (AAOT), and 
    acetoacet-o-anisidide (AAOA), were detected in some or all of the EPA 
    samples, but were not analyzed in the industry samples.
        The calculated risks from ingesting contaminated ground water 
    associated with disposing these sludges in on-site monofills are very 
    high. Three of the compounds that exceed risk levels of 1E-4 are common 
    raw materials used as coupling agents in the manufacture of azo 
    pigments: acetoacetanilide (AAA), acetoacet-o-anisidide (AAOA), and 
    acetoacet-o-toluidide (AAOT). These three compounds were expected to be 
    present in the waste, and consistently were found in the samples 
    collected by the Agency.
        The three coupling compounds present in this waste, AAA, AAOA, and 
    AAOT, are predicted to pose very high risks via ground-water ingestion 
    when managed in an on-site monofill. As shown in Table II-2, the 
    calculated risks posed by these compounds range from 1E-3 to 6E-4. 
    These risks were calculated using metabolic product structural-activity 
    relationships (SAR) for these compounds. A detailed discussion of the 
    SAR for these compounds, and the estimation of toxicities for AAA, 
    AAOA, and AAOT is presented earlier in this preamble, under Section 
    II.C, Description of Health and Risk Assessments, and in the Health 
    Assessment Background Document for this proposed rule, which is located 
    in the RCRA Docket for this rulemaking (See addresses section).
        These three compounds are high-volume couplers used in the 
    manufacture of azo pigments. Based on RCRA Section 3007 Questionnaire 
    data, AAA is the third highest-volume reactant in the pigment industry, 
    with over 8200 metric tons used in 1991. AAOT and AAOA also are used in 
    high volumes; their 1991 use volumes were 2600 and 850 Mtons, 
    respectively.
        AAA, AAOT, and AAOA were found in 85% of the wastewater systems 
    where they are used. When detected in the wastewater system, the 
    compound was found either in the wastewater or in the sludge. Table II-
    4 presents the number of wastewater systems where each of the three 
    coupling compounds were detected. Table II-4 also shows the number of 
    samples in which the three coupling compounds were detected relative to 
    the number in which the compounds were expected.
    
                                                       Table II-4                                                   
    ----------------------------------------------------------------------------------------------------------------
                                               WWT System                Wastewater                  Sludge         
    ----------------------------------------------------------------------------------------------------------------
    AAA...............................  5 of 5 systems..........  4 of 4 samples..........  5 of 5 samples.         
    AAOA..............................  2 of 4 systems..........  3 of 3 samples..........  1 of 2 samples.         
    AAOT..............................  4 of 4 systems..........  1 of 4 samples..........  4 of 4 samples.         
    ----------------------------------------------------------------------------------------------------------------
    
        Amides (e.g., AAA, AAOT, and AAOA) hydrolyze to form free acids and 
    amine salts under acidic conditions. Measurements of pH values of 
    process wastewaters at several pigment production facilities revealed 
    that these acidic conditions are encountered frequently. The hydrolysis 
    products for AAA, AAOT, and AAOA are aniline, 2-aminotoluene, and 2-
    methoxyaniline, respectively. The unreacted amide raw materials and the 
    amines expected from hydrolysis of these amides both have been 
    identified in untreated wastewaters and wastewater biological treatment 
    sludges.
        Two sets of coeluting compounds were observed from the analysis of 
    wastewater treatment sludge from the production of azo pigments. The 
    first set of coeluting compounds produced one data point, shown in 
    Table E1, for which the mass spectrum indicates the presence of 2-
    methoxyaniline, along with the potential presence of 2- and 4-
    aminoaniline (for a discussion of coeluting compounds and risk 
    assessments conducted on these compounds, please refer to the section 
    entitled ``Coeluting Compounds'' in Section II.D). 2-Methoxyaniline is 
    expected as a contaminant in the wastewater treatment sludge from the 
    facility that generated the sample because that facility manufactures 
    azo pigments using acetoacet-o-anisidide (AAOA) as a raw material, and, 
    as stated above, 2-methoxyaniline is an expected hydrolysis product of 
    AAOA. In addition, the facility from which this sample was collected 
    uses 2-aminoaniline as a reactant in the manufacture of azo dyes.
        For this wastestream, the Agency conducted the risk assessment for 
    these coeluting compounds based on toxicity information for 2-
    methoxyaniline because this contaminant is expected to be present from 
    azo pigment production. Since there currently is no HBL for 2-
    methoxyaniline, the Agency based the risk assessment on the toxicity of 
    a surrogate compound. 2-Aminotoluene is a structural analog of 2-
    methoxyaniline and is being used as a toxicity surrogate. The resulting 
    high-end individual cancer-risk level for 2-methoxyaniline was 
    calculated to be 2E-3 for the on-site monofill management scenario.
        The second set of coeluting compounds consists of the two isomers 
    2- and 4-aminotoluene. The two isomers were detected in 3 out of 8 
    sludge samples from azo pigment manufacturing operations, and the 
    combined concentration of the two compounds was quantified. The 
    calculated high-end individual cancer-risk level, based on the toxicity 
    of 2-aminotoluene, is 3E-5 for the on-site monofill management 
    scenario.
        In addition to the substantial calculated risks (i.e., exceeding 
    1E-4 for carcinogens) posed by raw materials used in azo pigment 
    manufacturing and their break-down products, four additional 
    contaminants were found in the wastestream at concentrations that are 
    projected to pose very high risks (HQs of 1 or greater for non-
    carcinogens) through ingestion of contaminated ground water under 
    plausible management in an on-site monofill. 1,3-Dinitrobenzene, 
    nitrobenzene, and 2,4-dinitrophenol were found at concentrations that 
    resulted in calculated high-end HQs of 7, 9, and 1 respectively.
        In addition to assessing the risks associated with the individual 
    constituents found in the waste, the Agency considers the combined risk 
    of constituents that co-exist in the wastestream. In the case of 
    wastewater treatment sludges generated from the manufacture of azo 
    pigments, all of the diazotization and coupling reactants and breakdown 
    products previously discussed in this section (i.e., AAA, AAOT, AAOA, 
    aniline, 2-aminotoluene, and 2-methoxyaniline) are assumed to co-exist 
    in the wastestream. The reactants are used in numerous large-volume 
    pigments which are manufactured on a frequent basis. Since this sludge 
    is a commingled wastestream representing production from the entire 
    plant, the constituents are likely to be present simultaneously in the 
    waste. Therefore, the combined risk of these individual constituents, 
    which is projected to be very high (i.e., 8E-3 at the high end), also 
    was considered in making this listing determination.
        In addition to the very high risks posed by the plausible 
    management practice (a monofill), the calculated risks posed by the 
    current management practice (a municipal landfill) are also high. The 
    combined additive high-end risk for the reactants and breakdown 
    products previously discussed in this section (i.e., AAA, AAOT, AAOA, 
    aniline, 2-aminotoluene, and 2-methoxyaniline) is projected to be 1E-4 
    for the municipal landfill management practice. Therefore, EPA 
    concludes that even if the Agency considered current management and did 
    not consider plausible management, this wastestream would present a 
    substantial risk to human health and the environment, and should be 
    listed as hazardous.
        Three additional constituents (i.e., aniline, 3,3'-
    dimethylbenzidine, and 2-aminotoluene) were found in the wastewater 
    treatment sludge from azo pigment operations at concentrations that are 
    projected to pose risks within the Agency's risk range of concern 
    (i.e., 1E-4 to 1E-6 for carcinogens) using the on-site monofill 
    management scenario. Four constituents (i.e., AAOA, AAOT, AAA, and the 
    coeluting compounds 2-aminoaniline and 2-methoxyaniline) were found in 
    this waste at concentrations that pose risks between 1E-4 and 1E-6 for 
    carcinogens for the municipal landfill scenario. In addition, six 
    constituents pose risks within this range of potential concern through 
    indirect pathways.
        Based on an analysis of the risks associated with both current and 
    plausible management practices, EPA is proposing to list wastewater 
    treatment sludge from the production of azo pigments as a hazardous 
    waste, designated as EPA Hazardous Waste Number K162.
        For the reasons stated above, the Agency is proposing to add the 
    following constituents to Appendix VII to Part 261--Basis for Listing: 
    Aniline, 2-aminoaniline, 4-aminoaniline, 2-methoxyaniline, 2-
    aminotoluene, 4-aminotoluene, acetoacet-o-anisidide, acetoacet-o-
    toluidide, acetoacetanilide, 1,3-dinitrobenzene, 3,3'-
    dimethylbenzidine, nitrobenzene, and 2,4-dinitrophenol.
        In addition, acetoacet-o-anisidide, acetoacet-o-toluidide, 
    acetoacetanilide, 2-aminoaniline, 4-aminoaniline, 2- methoxyaniline, 
    and 1,3-dinitrobenzene are proposed to be added to Appendix VIII to 
    Part 261--Hazardous Constituents.
        b. Wastewaters from the production of azo pigments (K163).
    
    Summary
    
        The Agency is proposing to list wastewaters from the production of 
    azo pigments as hazardous wastes. This waste meets the criteria set out 
    at 40 CFR 261.11(a)(3) for listing a waste as hazardous and is capable 
    of posing a significant present or potential hazard to human health or 
    the environment. Based on ingestion of contaminated ground water, EPA 
    calculated high-end individual risk levels for three carcinogens that 
    exceed 1E-4 for disposal in an unlined on-site surface impoundment, the 
    plausible management scenario. The calculated combined carcinogenic 
    risk for these constituents is 3E-4 from exposure to contaminated 
    ground water for the surface impoundment management scenario. To 
    further support this listing, four additional contaminants pose 
    individual risks between 1E-4 and 1E-6 for the surface impoundment 
    scenario.
    
    Discussion
    
        Data from the RCRA Section 3007 Questionnaire show that the 1991 
    volume reported by the industry for the wastewater stream from azo 
    pigment production is 9,914,662 metric tons, or approximately 7.2 
    million gallons per day. Over 75% of wastewaters from azo pigment 
    manufacturing currently are pretreated and discharged to a publicly 
    owned treatment works (POTW). Most of these wastewaters are treated in 
    equalization and neutralization tanks prior to discharge to a POTW. A 
    smaller percentage of these wastewaters is subjected to aerobic 
    biological treatment in tanks, with subsequent NPDES discharge to a 
    surface water.
        As explained under Section II.D, Description of Health and Risk 
    Assessments, the risk assessment for these wastewaters was performed 
    using treatment in tanks as the current, or baseline, management 
    practice, and treatment in surface impoundments as a plausible 
    management scenario. The risks of increased cancer for exposure to this 
    waste are presented in Table II-5. The data presented in this table 
    represent six samples collected from four azo pigment manufacturing 
    facilities.
    
                          Table II-5.--Waste Characterization and Risk Estimates K163--Wastewaters From the Production of Azo Pigments                      
    --------------------------------------------------------------------------------------------------------------------------------------------------------
                             Baseline management           Plausible management scenario                         Waste characterization                     
                     ---------------------------------------------------------------------------------------------------------------------------------------
     Constituents of          Treat in tanks***                   Treat in SI***                                                                            
         concern     ----------------------------------------------------------------------   Avg.     High                                                 
                          Central                                                            conc.    conc.       Low conc.        # of pts        Notes    
                          tendency         High end     Central tendency      High end                                                                      
    --------------------------------------------------------------------------------------------------------------------------------------------------------
    2- & 4-           All............  ...............  Risk=5E-5         Risk=1E-4            f.n.     4.75  f.n. (J)........  2 of 6.......  J(1)         
     Aminoaniline/2-                                                                                                                                        
     Methoxyani-                                                                                                                                            
     line*.                                                                                                                                                 
    2-, 3-, & 4-      Constituents...  ...............  Risk=1E-5         Risk=2E-5            0.54      2.1  f.n. (J)........  4 of 6.......  J(3)         
     Aminoto-                                                                                                                                               
     luene**.                                                                                                                                               
    Aniline.........  Dropped........  ...............  Risk=2E-6         Risk=4E-6            f.n.     f.n.  f.n.............  4 of 5.......  .............
    Acetoacet-o-      After..........  ...............  Risk=5E-6         Risk=1E-5            f.n.     0.18  0.021(J)........  3 of 6.......  J(1), S      
     anisidide                                                                                                                                              
     (AAOA).                                                                                                                                                
    Acetoacet-o-      Bounding.......  ...............  Risk=5E-5         Risk=1E-4            2.06  .......  ................  1 of 6.......  S            
     toluidide                                                                                                                                              
     (AAOT).                                                                                                                                                
    Acetoacetanilide  Risk...........  ...............  Risk=4E-6         Risk=7E-6            f.n.     f.n.  f.n.............  4 of 6.......  S            
     (AAA).                                                                                                                                                 
    2,4- & 2,6-       Assessment.....  ...............  Risk=5E-5         Risk=1E-4            f.n.  .......  ................  f,n,.........  .............
     Dimethylaniline.                                                                                                                                       
    Combined          ...............  ...............  Risk=2E-4         Risk=3E-4                                                                         
     Carcinogen Risk.                                                                                                                                       
    --------------------------------------------------------------------------------------------------------------------------------------------------------
    *Risk estimates based on surrogate for 2-methoxyaniline.                                                                                                
    **Risk estimates based on 2-aminotoluene.                                                                                                               
    ***Exposure through ingestion of contaminated groundwater.                                                                                              
                                                                                                                                                            
    f.n. Relevant data are not included at the present time due to business confidentiality concerns.                                                       
                                                                                                                                                            
    Notes:                                                                                                                                                  
    All concentrations are in mg/l.                                                                                                                         
    J(#)--Samples where estimated concentrations are below quantitation limits, `(#)' indicates number of samples that are `J' values.                      
    S--Toxicity estimated based on metabolic similarity to chemical analog.                                                                                 
    
        The calculated risks associated with managing these wastewaters in 
    surface impoundments are very high. Three constituents are considered 
    to pose a substantial potential hazard to human health and the 
    environment (i.e., risks exceed 1E-4). Calculated risks for each of 
    these three compounds are 1E-4.
        Three of the constituents that have been projected to pose a risk 
    greater than 1E-6, namely, acetoacetanilide (AAA), acetoacet-o-
    toluidide (AAOT), and acetoacet-o-anisidide (AAOA), are high-volume 
    coupling reactants used in the manufacture of azo pigments. As 
    explained above for K162, these constituents are dominant raw materials 
    in the azo pigment manufacturing industry and generally are present in 
    the wastewater treatment systems at these sites. As shown in Table II-
    5, the risks calculated by these compounds range from 1E-4 to 1E-6. As 
    stated for K162, these risks were calculated using metabolic product 
    structural-activity relationships (SAR) for these compounds, an 
    approach which is discussed in detail in Section II.D of this preamble, 
    and in the Listing Background Document for this proposed rule, which is 
    located in the RCRA Docket for this rulemaking (See ADDRESSES section).
        Table II-4, presented earlier, shows that AAA and AAOA were 
    detected in all of the wastewater samples collected from facilities 
    that use these reactants. AAOT was found only in one of four wastewater 
    samples, but it was found in all four of the sludge samples collected 
    from facilities using the compound. The Agency believes that the latter 
    compound generally is present in the wastewater treatment system at 
    facilities that use AAOT as a raw material but that it may be 
    preferentially partitioning to the sludge.
        In addition to the high risks calculated by the three reactants, 
    AAA, AAOA, and AAOT, the hydrolysis products of these compounds, 
    aniline, 2-aminotoluene, and 2-methoxyaniline, also were detected in 
    the waste at concentrations that pose significant risk (i.e., risks 
    ranging from 1E-4 to 4E-6). Discussions addressing hydrolysis pathways 
    and conditions for these compounds, and the issue of coeluting 
    compounds associated with the hydrolysis products, were presented 
    earlier in this preamble (see discussion of K162, and Section II.D).
        In addition to the primary raw materials and breakdown products 
    presented above, the combined 2,4- and 2,6-isomers of dimethylaniline, 
    which also are suspected raw material breakdown products, were detected 
    in this waste at concentrations that pose a very high risk (i.e., a 
    risk of 1E-4).
        Along with risks associated with the individual constituents found 
    in the waste, the Agency considers the combined risks of constituents 
    that co-exist in the wastestream. In the case of wastewaters generated 
    from the manufacture of azo pigments, all of the reactants and 
    breakdown products previously discussed in this section (i.e., AAA, 
    AAOT, AAOA, aniline, 2-aminotoluene, and 2-methoxyaniline) are assumed 
    to co-exist in the wastestream. The reactants are used in producing 
    numerous large-volume pigments that are manufactured on a frequent 
    basis. Since this wastewater stream represents several commingled 
    wastestreams from throughout the plant, the constituents are likely to 
    be present simultaneously in the waste. Therefore, the combined risks 
    of these individual constituents, which are projected to be very high 
    under the surface impoundment mismanagment scenario (i.e., 3E-4 at the 
    high end), also were considered in making this listing determination.
        Based on the calculated risks associated with the plausible 
    management practice for this waste (treatment in surface impoundments), 
    EPA is proposing to list wastewaters from the production of azo 
    pigments as a hazardous waste, designated EPA Hazardous Waste Number 
    K163. However, the Agency recognizes that if wastewater treatment 
    sludges from the production of azo pigments (K162) are listed as 
    proposed, the available options for wastewater management may change 
    and the surface impoundment scenario may not be plausible for the 
    following reason: wastewaters that are managed in an impoundment will 
    generate sludges through precipitation. In the event that K162 sludges 
    were listed and the wastewaters were not, the sludges generated in a 
    Subtitle D wastewater impoundment would be hazardous wastes and the 
    surface impoundment would become subject to RCRA Subtitle C regulation. 
    The Agency is requesting comment on whether the use of Subtitle D 
    surface impoundments to manage wastewaters would be a plausible 
    management scenario if the wastewaters were not listed but the 
    wastewater treatment sludges were listed as hazardous wastes. The 
    Agency also is requesting comment on the need to list K163 wastewaters, 
    given that the plausibility of the management scenario on which the 
    risk assessment was based may be affected by the final outcome of the 
    K162 sludge listing.
        For the reasons stated above, EPA proposes to add the following 
    constituents to Appendix VII to Part 261--Basis for Listing: Aniline, 
    2-aminoaniline, 4-aminoaniline, 2-methoxyaniline, 2-aminotoluene, 3-
    aminotoluene, 4-aminotoluene, acetoacet-o-anisidide, acetoacet-o-
    toluidide, acetoacetanilide, 2,4-dimethylaniline, and 2,6-
    dimethylaniline.
        In addition, 2-aminoaniline, 4-aminoaniline, 2-methoxyaniline, 3-
    aminotoluene, acetoacet-o-anisidide, acetoacet-o-toluidide, 
    acetoacetanilide, 2,4-dimethylaniline, and 2,6-dimethylaniline are 
    proposed to be added to Appendix VIII to Part 261--Hazardous 
    Constituents.
        2. Wastes from the production of azo dyes.
        a. Wastewater treatment sludge from the production of azo dyes, 
    excluding FD&C colorants (K164).
    Summary
        EPA is proposing to list wastewater treatment sludge from the 
    production of azo dyes, excluding FD&C colorants, as a hazardous waste. 
    This wastestream meets the criteria set out at 40 CFR 261.11(a)(3) for 
    listing a waste as hazardous and is capable of posing a substantial 
    present or potential risk to human health or the environment. Based on 
    ingestion of contaminated ground water, EPA calculated high-end 
    individual cancer risk levels for five constituents which exceed 1E-4 
    for carcinogens and have HQs of 1 or greater for non-carcinogens for 
    the plausible management practice, an on-site monofill. Four additional 
    contaminants further support the listing by posing individual risks 
    between 1E-4 and 1E-6. Risks between 1E-4 and 1E-6 also were identified 
    for six contaminants from exposure to these constituents through other 
    exposure pathways.
    Discussion
        The majority of wastewater treatment sludge from the production of 
    azo dyes is biological treatment sludge. The information on volume and 
    the percentage of this waste volume disposed of at Subtitle D municipal 
    landfills, as reported in the 1992 RCRA Section 3007 Questionnaire, is 
    not included at the present time due to business confidentiality 
    concerns.
    
                    Table II-6.--Waste Characterization and Risk Estimates, K154--Wastewater Treatment Sludge From the Production of Azo Dyes               
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                           Baseline management#            Plausible management scenario                            Waste characterization                  
                         -----------------------------------------------------------------------------------------------------------------------------------
       Constituents of    Municipal landfill****   On-site monofill****     Vegetable ingestion                                                             
           concern       ------------------------------------------------------------------------   Avg.     High     Low                                   
                            Central                 Central                 Central                conc.    conc.    conc.      # of pts          Notes     
                             tend.     High end      tend.     High end      tend.     High end                                                             
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                      2-  R=4E-6      R=2E-5      R=2E-4      R=5E-4      R=4E-5      R=4E-5         7.17  .......  .......  1 of 7.......  J               
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    Aniline.............  R<1e-6><1e-6 r="2E-6" r="1E-5" r="2E-6" r="2E-6" f.n.="" f.n.="" 14="" f.n..........="" ................="" diphenylamine/n-=""><1e-6><1e-6><1e-6 r="2E-6" ..........="" ..........="" f.n.="" f.n.="" f.n.="" f.n..........="" j="" nitrosodi-="" phenylamine**.="" 3,3'-=""><1e-6><1e-6 r="4E-6" r="2E-5" r="3E-6" r="3E-6" f.n.="" f.n.="" f.n.="" f.n..........="" ................="" dimethoxybenzidine.="" 4-methylphenol......=""><1e-6><1e-6 hq="2" hq="3" ..........="" ..........="" 9.5="" .......="" .......="" 1="" of="" 7.......="" ................="" 1,3-dinitrobenzene..="" hq="">< 1="" hq="">< 1="" hq="34" hq="45" ..........="" ..........="" 1.05="" 1.6="" 0.72="" 3="" of="" 8.......="" j="" 2-methoxy-5-=""><1e-6><1e-6><1e-6 r="2E-6" r="5E-6" r="5E-6" 0.92="" .......="" .......="" 1="" of="" 10......="" j(3),i(3)="" nitroaniline.="" 2,4-dinitrophenol...="" hq="">< 1="" hq="">< 1="" hq="1" hq="2" ..........="" ..........="" 0.74="" .......="" .......="" 1="" of="" 18......="" j,i="" 2-="" &="" 4-aminoto-=""><1e-6 r="1E-6" r="3E-5" r="1E-4" r="1E-5" r="2E-5" 1.3="" 1.5="" 1.2="" 3="" of="" 11......="" j(5),i(9)="" luene***.="" combined="" r="4E-6" r="2E-5" r="2E-4" r="7E-4" carcinogenic="" risk.="" --------------------------------------------------------------------------------------------------------------------------------------------------------="" #="" underestimates="" risks="" due="" to="" disposal="" in="" on-site="" monofill,="" not="" included="" in="" estimate.="" *="" risk="" numbers="" based="" on="" 2-aminoaniline.="" **="" risk="" numbers="" based="" on="" n-nitrosodiphenylamine.="" ***="" risk="" numbers="" based="" on="" 2-aminotoluene.="" ****="" exposure="" through="" ingestion="" of="" ground="" water.="" f.n.="" relevant="" data="" are="" not="" included="" at="" the="" present="" time="" due="" to="" business="" confidentiality="" concerns.="" notes:="" all="" concentrations="" are="" in="" mg/kg.="" j(#)--samples="" where="" estimated="" concentrations="" are="" below="" quantitation="" limits,="" `(#)'="" indicates="" number="" of="" samples="" that="" are="" `j'="" values.="" i(#)--includes="" data="" supplied="" by="" industry,="" `(#)'="" indicates="" number="" of="" samples="" that="" are="" industry-supplied.="" s--toxicity="" estimated="" based="" on="" metabolic="" similarity="" to="" chemical="" analog.="" as="" discussed="" earlier="" under="" section="" ii.d,="" description="" of="" health="" and="" risk="" assessments,="" the="" agency="" conducted="" the="" risk="" assessment="" on="" these="" wastestreams="" using="" both="" a="" current,="" or="" baseline="" management="" scenario,="" and="" a="" plausible="" management="" scenario.="" information="" relating="" to="" this="" discussion="" is="" not="" included="" at="" the="" present="" time="" due="" to="" business="" confidentiality="" concerns.="" therefore,="" the="" agency="" conducted="" the="" risk="" assessment="" on="" two="" current="" management="" scenarios,="" a="" municipal="" landfill,="" and="" a="" monofill,="" with="" the="" monofill="" representing="" the="" plausible="" management="" practice.="" the="" risk="" projections="" associated="" with="" this="" wastestream="" are="" presented="" in="" table="" ii-6.="" the="" data="" presented="" in="" this="" table="" represent="" 18="" samples="" collected="" from="" four="" azo="" dye="" manufacturing="" facilities.="" eleven="" of="" the="" 18="" samples="" were="" collected="" and="" analyzed="" by="" industry,="" and="" were="" submitted="" to="" epa="" for="" evaluation.="" the="" risks="" associated="" with="" disposing="" these="" sludges="" in="" monofills="" are="" projected="" to="" be="" very="" high.="" five="" constituents="" found="" in="" the="" waste="" are="" predicted="" to="" pose="" individual="" high-end="" cancer-risk="" levels="" equal="" to="" or="" exceeding="" 1e-4="" or="" hqs="" equal="" to="" or="" exceeding="" 1="" for="" non-carcinogens,="" through="" ingestion="" of="" contaminated="" ground="" water="" or="" vegetables.="" the="" five="" constituents="" pose="" carcinogenic="" risks="" ranging="" from="" 1e-4="" to="" 5e-4="" and="" non-="" carcinogenic="" hazards="" from="" 2="" to="" 45="" times="" above="" the="" rfds="" for="" the="" monofill="" management="" scenario.="" there="" are="" two="" cases="" of="" coeluting="" constituents="" for="" this="" wastestream.="" as="" shown="" in="" table="" ii-6,="" there="" is="" one="" data="" point="" for="" which="" the="" mass="" spectrum="" indicates="" the="" presence="" of="" 2-="" methoxyaniline,="" along="" with="" the="" potential="" presence="" of="" 2-="" and="" 4-="" aminoaniline.="" as="" discussed="" in="" section="" ii.d,="" epa="" based="" the="" risk="" assessment="" for="" this="" set="" of="" coeluting="" compounds="" on="" 2-aminoaniline.="" the="" calculated="" high-end="" individual="" cancer-risk="" level="" for="" 2-="" aminoaniline="" is="" 5e-4="" for="" the="" monofill="" management="" scenario.="" the="" second="" set="" of="" coeluting="" compounds="" consists="" of="" the="" three="" isomers="" 2-,="" 3-,="" and="" 4-aminotoluene.="" the="" presence="" of="" the="" three="" isomers="" was="" confirmed="" in="" four="" out="" of="" six="" wastewater="" samples="" collected="" from="" azo="" dye="" manufacturing="" operations,="" and="" the="" combined="" concentration="" of="" the="" three="" compounds="" was="" quantified.="" the="" calculated="" high-end="" individual="" cancer-="" risk="" level,="" based="" on="" the="" toxicity="" of="" 2-aminotoluene,="" is="" 1e-4="" for="" the="" monofill="" management="" scenario="" (see="" section="" ii.d="" of="" this="" preamble,="" coeluting="" compounds,="" for="" more="" details="" on="" the="" agency's="" approach="" to="" risk="" assessment="" for="" coeluting="" compounds).="" in="" addition="" to="" the="" two="" sets="" of="" coeluting="" compounds="" used="" as="" raw="" materials="" in="" azo="" dye="" manufacturing,="" three="" compounds,="" 1,3-="" dinitrobenzene,="" 4-methylphenol,="" and="" 2,4-dinitrophenol="" were="" found="" at="" concentrations="" that="" are="" projected="" to="" pose="" a="" substantial="" risk="" to="" human="" health="" and="" the="" environment.="" the="" risks="" presented="" by="" these="" compounds="" are="" calculated="" to="" have="" high-end="" hqs="" of="" 45,="" 3,="" and="" 2,="" respectively.="" aniline="" is="" a="" high-volume="" dye="" reactant="" present="" in="" the="" wastewater="" treatment="" sludge="" at="" multiple="" facilities,="" according="" to="" rcra="" section="" 3007="" questionnaire="" data.="" aniline="" is="" the="" fourth="" highest-volume="" reactant="" used="" in="" the="" dye="" industry,="" according="" to="" data="" provided="" in="" the="" 1991="" rcra="" section="" 3007="" questionnaires,="" with="" a="" 1991="" use="" volume="" of="" 4860="" metric="" tons.="" based="" on="" the="" aniline="" concentrations="" found="" in="" the="" waste,="" the="" agency="" has="" calculated="" a="" high-end="" individual="" cancer-risk="" level="" for="" this="" constituent="" at="" 1e-5.="" aniline="" was="" found="" in="" over="" 70%="" of="" the="" samples="" of="" wastewater="" treatment="" sludge="" from="" azo="" dye="" production.="" however,="" 11="" of="" the="" 13="" aniline="" data="" points,="" which="" were="" all="" from="" one="" facility,="" were="" dropped="" prior="" to="" the="" risk="" assessment="" because="" the="" facility="" reported="" that="" aniline="" found="" in="" the="" wastewater="" treatment="" sludges="" is="" associated="" with="" non-dye="" operations.="" this="" facility="" consumes="" larger="" volumes="" of="" aniline="" in="" their="" non-dye="" operations="" than="" in="" the="" manufacture="" of="" azo="" dyes.="" it="" is="" likely="" that="" aniline="" from="" dye="" operations="" contributed="" to="" the="" presence="" of="" the="" constituent="" in="" the="" waste;="" however,="" the="" agency="" could="" not="" determine="" the="" extent="" of="" this="" contribution.="" in="" studying="" the="" wastewater="" treatment="" systems="" from="" azo="" dye="" manufacturing="" operations="" as="" a="" whole,="" the="" agency="" found="" aniline="" to="" be="" present="" in="" all="" systems="" from="" which="" samples="" were="" collected.="" in="" addition,="" aniline="" was="" consistently="" present="" in="" the="" wastewaters="" for="" all="" samples="" collected.="" furthermore,="" even="" though="" aniline="" would="" be="" expected="" to="" biodegrade="" in="" the="" wastewater="" treatment="" system,="" aniline="" was="" present="" in="" 2="" out="" of="" 5="" samples="" from="" the="" wastewater="" treatment="" sludge.="" because="" the="" wastewater="" treatment="" sludge="" presents="" a="" complex="" matrix="" for="" chemical="" analysis,="" the="" detection="" limits="" obtained="" for="" the="" wastewater="" treatment="" sludges="" were="" high.="" therefore,="" the="" agency="" believes="" that,="" given="" the="" consistent="" presence="" of="" aniline="" in="" the="" wastewater,="" and="" the="" detection="" of="" aniline="" in="" 2="" out="" of="" 5="" sludge="" samples="" (with="" 11="" data="" points="" dropped="" for="" the="" reasons="" stated="" earlier),="" aniline="" typically="" is="" present="" in="" wastewater="" treatment="" sludges="" from="" azo="" dye="" manufacturing="" operations.="" based="" on="" the="" aniline="" concentrations="" found="" in="" the="" two="" data="" points="" that="" remain="" after="" 11="" data="" points="" were="" dropped,="" the="" agency="" has="" determined="" that="" the="" risk="" posed="" by="" aniline="" in="" this="" wastestream="" is="" significant.="" an="" additional="" high-volume="" raw="" material="" used="" in="" the="" manufacture="" of="" azo="" dyes,="" 3,3'-dimethoxybenzidine,="" was="" found="" to="" be="" present="" in="" the="" wastewater="" treatment="" sludge="" from="" azo="" dye="" operations="" at="" concentrations="" that="" result="" in="" calculated="" high-end="" individual="" cancer-risk="" level="" of="" 2e-="" 5.="" based="" on="" data="" from="" the="" 1991="" rcra="" section="" 3007="" questionnaire,="" 1719="" metric="" tons="" of="" 3,3'-dimethyoxybenzidine="" were="" used="" in="" the="" manufacture="" of="" azo="" dyes="" in="" 1991.="" in="" addition="" to="" the="" risks="" posed="" by="" the="" individual="" hazardous="" constituents="" found="" in="" the="" waste,="" some="" of="" the="" contaminants="" are="" co-="" occurring="" in="" this="" wastestream.="" the="" agency="" found="" that="" sludge="" samples="" collected="" from="" each="" of="" the="" four="" azo="" dye="" manufacturing="" facilities="" generally="" contain="" one="" or="" more="" toxic="" raw="" materials="" simultaneously.="" therefore,="" some="" individual="" carcinogens="" are="" co-occurring="" in="" the="" waste="" and="" the="" calculated="" risks="" are="" assumed="" to="" be="" additive.="" given="" the="" waste="" characterization="" and="" risk="" assessment="" results,="" along="" with="" toxicity="" information="" on="" other="" raw="" materials="" used="" in="" the="" production="" of="" azo="" dyes="" (i.e.,="" aromatic="" amines),="" the="" agency="" believes="" that="" wastewater="" treatment="" sludges="" from="" azo="" dye="" manufacturing="" typically="" contain="" one="" or="" more="" toxic="" raw="" materials="" at="" concentrations="" that="" pose="" a="" significant="" risk.="" in="" addition="" to="" the="" azo="" dye="" raw="" materials="" that="" were="" found="" in="" the="" wastestream="" at="" concentrations="" that="" pose="" a="" high="" risk,="" two="" additional="" constituents,="" 2-methoxy-5-nitroaniline,="" and="" the="" two="" coeluting="" compounds="" diphenylamine="" and="" n-nitrosodiphenylamine,="" were="" found="" in="" the="" wastewater="" treatment="" sludge="" from="" azo="" dye="" operations="" at="" concentrations="" that="" pose="" carcinogenic="" risks="" above="" 1e-6="" (see="" section="" ii.d="" for="" treatment="" of="" coeluting="" compounds).="" the="" results="" from="" the="" assessment="" of="" exposure="" pathways="" other="" than="" drinking="" contaminated="" ground="" water="" resulting="" from="" management="" in="" an="" on-="" site="" monofill="" also="" are="" presented="" in="" table="" ii-6.="" calculated="" high-end="" individual="" cancer-risk="" levels="" between="" 1e-4="" and="" 1e-6="" were="" identified="" for="" six="" contaminants="" through="" indirect="" exposure="" pathways="" (contaminated="" vegetable="" ingestion)="" if="" airborne="" dusts="" are="" not="" controlled.="" in="" addition="" to="" the="" risks="" posed="" by="" the="" monofill="" management="" practice,="" the="" calculated="" risk="" posed="" by="" municipal="" landfill="" disposal="" also="" is="" within="" epa's="" range="" of="" potential="" concern,="" 1e-6="" to="" 1e-4,="" for="" two="" sets="" of="" coeluting="" compounds,="" 2-="" and="" 4-aminoaniline/2-methoxyaniline,="" and="" 2-="" and="" 4-aminotoluene.="" the="" agency="" also="" considered="" the="" risks="" posed="" by="" these="" contaminants="" for="" a="" municipal="" landfill="" when="" making="" the="" listing="" decision.="" based="" on="" an="" analysis="" of="" the="" risks="" associated="" with="" the="" current="" management="" practices,="" a="" monofill="" and="" municipal="" landfill,="" epa="" is="" proposing="" to="" list="" as="" hazardous="" wastewater="" treatment="" sludge="" from="" the="" production="" of="" azo="" dyes,="" excluding="" fd&c="" colorants,="" designated="" epa="" hazardous="" waste="" number="" k164.="" for="" the="" reasons="" stated="" above,="" the="" agency="" is="" proposing="" to="" add="" the="" following="" constituents="" to="" appendix="" vii="" to="" part="" 261--basis="" for="" listing:="" 2-aminoaniline,="" 4-aminoaniline,="" 2-methoxyaniline,="" aniline,="" diphenylamine,="" n-nitrosodiphenylamine,="" 3,3'-dimethoxybenzidine,="" 4-="" methylphenol,="" 1,3-dinitrobenzene,="" 2-methoxy-5-nitroaniline,="" 2,4-="" dinitrophenol,="" 2-aminotoluene,="" and="" 4-aminotoluene.="" in="" addition,="" 2-aminoaniline,="" 4-aminoaniline,="" 2-methoxyaniline,="" n-="" nitrosodiphenylamine,="" 4-methylphenol,="" 1,3-dinitrobenzene,="" and="" 2-="" methoxy-5-nitroaniline="" are="" proposed="" to="" be="" added="" to="" appendix="" viii="" to="" part="" 261--hazardous="" constituents.="" b.="" wastewaters="" from="" the="" production="" of="" azo="" dyes,="" excluding="" fd&c="" colorants="" (k165).="" summary="" the="" agency="" is="" proposing="" to="" list="" wastewaters="" from="" the="" production="" of="" azo="" dyes,="" excluding="" fd&c="" colorants,="" as="" hazardous.="" this="" wastestream="" meets="" the="" criteria="" set="" out="" at="" 40="" cfr="" 261.11(a)(3)="" for="" listing="" a="" waste="" as="" hazardous="" and="" is="" capable="" of="" posing="" a="" substantial="" present="" or="" potential="" hazard="" to="" human="" health="" or="" the="" environment.="" based="" on="" ingestion="" of="" contaminated="" ground="" water,="" epa="" calculated="" a="" high-end="" individual="" risk="" level="" of="" 1e-4="" for="" one="" hazardous="" constituent="" for="" the="" plausible="" management="" scenario,="" treatment="" in="" an="" unlined="" surface="" impoundment.="" two="" additional="" constituents="" are="" estimated="" to="" pose="" risks="" between="" 1e-4="" and="" 1e-6="" for="" the="" surface="" impoundment="" scenario.="" discussion="" based="" on="" response="" data="" from="" the="" 1991="" rcra="" section="" 3007="" questionnaire,="" the="" volume="" reported="" by="" the="" industry="" for="" wastewaters="" from="" azo="" dye="" production,="" excluding="" fd&c="" colorants,="" was="" 6,295,779="" metric="" tons="" per="" year,="" or="" 4.6="" million="" gallons="" per="" day.="" approximately="" 58%="" of="" wastewaters="" from="" azo="" dye="" production,="" excluding="" fd&c="" colorants="" currently="" are="" pretreated="" and="" discharged="" to="" a="" potw.="" over="" 40%="" of="" these="" wastewaters="" are="" treated="" in="" aerobic="" biological="" tank="" systems,="" with="" subsequent="" npdes="" discharge="" to="" a="" surface="" water.="" approximately="" 5%="" of="" the="" wastewaters="" from="" azo="" dye="" operations="" excluding="" fd&c="" colorants="" are="" treated="" in="" biological="" treatment="" systems="" that="" use="" surface="" impoundments.="" as="" discussed="" earlier="" under="" section="" ii.d,="" description="" of="" health="" and="" risk="" assessments,="" the="" risk="" assessment="" for="" these="" wastewaters="" was="" performed="" using="" treatment="" in="" tanks="" as="" the="" current,="" or="" baseline,="" management="" practice,="" and="" treatment="" in="" surface="" impoundments="" as="" a="" plausible="" management="" scenario.="" for="" this="" waste,="" however,="" the="" worst-case="" management="" scenario,="" treatment="" in="" a="" surface="" impoundment,="" is="" also="" one="" of="" the="" current="" management="" practices.="" the="" calculated="" risks="" of="" increased="" cancer="" or="" hazard="" quotient="" above="" one="" for="" exposure="" to="" this="" waste="" are="" presented="" in="" table="" ii-7.="" the="" data="" presented="" in="" this="" table="" represent="" seven="" samples="" collected="" from="" five="" azo="" dye-manufacturing="" facilities.="" table="" ii-7--waste="" characterization="" and="" risk="" estimates="" k165--wastewaters="" from="" the="" production="" of="" azo="" dyes,="" excluding="" fd&c="" colorants="" --------------------------------------------------------------------------------------------------------------------------------------------------------="" baseline="" management="" plausible="" management="" waste="" characterization="" ---------------------------------------------------------------------------------------------------------------------------------------="" constituents="" of="" treat="" in="" tanks***="" treat="" in="" si***="" concern="" ----------------------------------------------------------------------="" avg.="" high="" central="" conc.="" conc.="" low="" conc.="" #="" of="" pts="" notes="" tendency="" high="" end="" central="" tendency="" high="" end="" --------------------------------------------------------------------------------------------------------------------------------------------------------="" 2-="" &="" 4-="" insignificant="" ...............="" risk="6E-6" risk="1E-5" f.n.="" 4.75="" f.n.............="" 3="" of="" 8.......="" .............="" aminoaniline/2-="" risk="" for="" any="" methoxyani-="" constituent.="" line*.="" 2-,="" 3-,="" &="" 4-="" ...............="" ...............="" risk="6E-5" risk="1E-4" f.n.="" f.n.="" 0.048="" (j).......="" 6="" of="" 8.......="" j(2)="" aminoto-="" luene**.="" aniline.........="" ...............="" ...............="" risk=""><1e-6 risk="2E-6" f.n.="" f.n.="" 0.063...........="" 5="" of="" 5.......="" .............="" combined="" ...............="" ...............="" risk="6E-5" risk="1E-4" carcinogenic="" risk.="" --------------------------------------------------------------------------------------------------------------------------------------------------------="" *risk="" estimates="" based="" on="" 2-aminoaniline.="" **risk="" estimates="" based="" on="" 2-aminotoluene.="" ***exposure="" through="" ingestion="" of="" contaminated="" ground="" water.="" f.n.="" relevant="" data="" are="" not="" included="" at="" the="" present="" time="" due="" to="" business="" confidentiality="" concerns.="" notes:="" all="" concentrations="" are="" in="" mg/l.="" j(#)--samples="" where="" estimated="" concentrations="" are="" below="" quantitation="" limits,="" `(#)'="" indicates="" number="" of="" samples="" that="" are="" `j'="" values.="" s--toxicity="" estimated="" based="" on="" metabolic="" similarity="" to="" chemical="" analog.="" the="" risk="" associated="" with="" the="" wastewaters="" in="" tanks="" is="" estimated="" to="" be="" below="" levels="" of="" concern.="" however,="" the="" risks="" associated="" with="" managing="" these="" wastewaters="" in="" surface="" impoundments="" are="" calculated="" to="" be="" high.="" one="" constituent="" found="" in="" the="" waste="" is="" considered="" capable="" of="" posing="" a="" substantial="" present="" or="" potential="" risk="" to="" human="" health="" or="" the="" environment="" (i.e.,="" risks="" are="" 1e-4="" or="" higher="" for="" carcinogens,="" or="" 1="" or="" higher="" hqs="" for="" non-carcinogens).="" the="" constituent="" poses="" a="" risk="" 1e-4.="" as="" was="" the="" case="" with="" wastewater="" treatment="" sludge="" from="" the="" production="" of="" azo="" dyes,="" excluding="" fd&c="" colorants,="" the="" wastewaters="" were="" found="" to="" contain="" high="" concentrations="" of="" aniline,="" a="" high-volume="" dye="" reactant="" that="" poses="" an="" unacceptable="" risk="" at="" such="" levels.="" in="" fact,="" aniline="" was="" present="" in="" each="" of="" the="" seven="" wastewater="" samples="" from="" azo="" dye="" production.="" however,="" two="" of="" the="" seven="" aniline="" data="" points,="" which="" were="" both="" from="" one="" facility,="" were="" dropped="" prior="" to="" the="" risk="" assessment="" because="" the="" facility="" reported="" that="" aniline="" found="" in="" the="" wastewater="" is="" associated="" with="" non-dye="" operations.="" this="" facility="" consumes="" larger="" volumes="" of="" aniline="" in="" their="" non-dye="" operations="" than="" in="" the="" manufacture="" of="" azo="" dyes.="" it="" is="" likely="" that="" aniline="" from="" dye="" operations="" contributed="" to="" the="" presence="" of="" the="" constituent="" in="" the="" waste;="" however,="" the="" agency="" could="" not="" determine="" the="" extent="" of="" this="" contribution.="" based="" on="" the="" aniline="" concentrations="" represented="" by="" the="" five="" remaining="" data="" points,="" the="" agency="" has="" determined="" that="" the="" risks="" posed="" by="" aniline="" in="" this="" wastestream="" are="" 2e-6).="" the="" presence="" of="" three="" coeluting="" isomers,="" 2-,="" 3-,="" and="" 4-="" aminotoluene,="" was="" confirmed="" in="" four="" out="" of="" six="" wastewater="" samples="" collected="" from="" azo="" dye="" manufacturing="" operations,="" and="" the="" combined="" concentration="" of="" the="" three="" compounds="" was="" quantified="" (refer="" to="" earlier="" discussion="" under="" section="" ii.d.2,="" coeluting="" compounds,="" for="" a="" discussion="" on="" the="" coelution="" of="" 2-,="" 3-,="" and="" 4-aminotoluene).="" the="" calculated="" high-="" end="" individual="" cancer-risk="" level,="" based="" on="" the="" toxicity="" of="" 2-="" aminotoluene,="" is="" 1e-4="" for="" the="" surface="" impoundment="" management="" scenario.="" the="" second="" set="" of="" coeluting="" compounds="" consists="" of="" 2-="" and="" 4-="" aminoaniline,="" and="" 2-methoxyaniline.="" epa="" based="" the="" risk="" assessment="" for="" this="" set="" of="" coeluting="" compounds="" on="" 2-aminoaniline,="" as="" discussed="" in="" section="" ii.d.2.="" the="" resulting="" calculated="" high-="" end="" individual="" cancer-="" risk="" level="" is="" 1e-5="" for="" the="" surface="" impoundment="" management="" scenario.="" based="" on="" the="" risks="" associated="" with="" the="" plausible="" management="" practice="" for="" this="" waste,="" epa="" is="" proposing="" to="" list="" wastewaters="" from="" the="" production="" of="" azo="" dyes,="" excluding="" fd&c="" colorants,="" as="" a="" hazardous="" waste,="" designated="" epa="" hazardous="" waste="" number="" k165.="" however,="" the="" agency="" recognizes="" that="" if="" wastewater="" treatment="" sludges="" from="" the="" production="" of="" azo="" dyes="" (k164)="" are="" listed="" as="" proposed,="" the="" available="" options="" for="" wastewater="" management="" may="" change="" and="" surface="" impoundments="" may="" not="" be="" used.="" wastewaters="" that="" are="" managed="" in="" an="" impoundment="" will="" generate="" sludges="" through="" precipitation.="" in="" the="" event="" that="" k164="" sludges="" were="" listed="" and="" the="" wastewaters="" were="" not,="" the="" sludges="" generated="" in="" a="" subtitle="" d="" wastewater="" impoundment="" would="" be="" hazardous="" wastes="" and="" the="" surface="" impoundment="" would="" become="" subject="" to="" rcra="" subtitle="" c="" regulation.="" the="" agency="" is="" requesting="" comment="" on="" whether="" it="" would="" be="" plausible="" to="" use="" a="" subtitle="" d="" surface="" impoundment="" to="" manage="" wastewaters="" if="" the="" wastewaters="" were="" not="" listed="" and="" the="" wastewater="" treatment="" sludges="" were="" listed="" as="" hazardous="" wastes.="" the="" agency="" also="" is="" requesting="" comment="" on="" the="" need="" to="" list="" k165="" wastewaters,="" given="" that="" the="" plausibility="" of="" the="" worst-case="" management="" scenario="" on="" which="" the="" risk="" assessment="" was="" based="" may="" be="" affected="" by="" the="" k164="" sludge="" listing.="" for="" the="" reasons="" stated="" above,="" epa="" proposes="" to="" add="" the="" following="" constituents="" to="" appendix="" vii="" to="" part="" 261--basis="" for="" listing:="" 2-="" aminoaniline,="" 2-methoxyaniline,="" 2-aminotoluene,="" 3-="" aminotoluene,="" 4-="" aminotoluene,="" and="" aniline.="" in="" addition,="" 2-aminoaniline,="" 4-aminoaniline,="" 2-methoxyaniline="" and="" 3-aminotoluene="" are="" proposed="" to="" be="" added="" to="" appendix="" viii="" to="" part="" 261--="" hazardous="" constituents.="" 3.="" wastes="" from="" the="" production="" of="" triarylmethane="" dyes="" and="" pigments="" (excluding="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock).="" a.="" wastewater="" treatment="" sludge="" from="" the="" production="" of="" triarylmethane="" dyes="" and="" pigments="" (excluding="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock).="" summary="" epa="" is="" proposing="" to="" defer="" the="" decision="" on="" whether="" to="" list="" wastewater="" treatment="" sludges="" from="" the="" production="" of="" triarylmethane="" dyes="" and="" pigments="" (excluding="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock)="" due="" to="" insufficient="" waste="" characterization="" data.="" the="" agency="" is="" planning="" to="" collect="" additional="" information="" on="" this="" wastestream.="" epa="" then="" will="" publish="" a="" supplemental="" notice="" with="" a="" proposed="" determination="" on="" whether="" to="" list="" this="" waste.="" discussion="" this="" waste="" is="" generated="" from="" the="" treatment="" of="" wastewaters="" from="" triarylmethane="" dye="" and="" pigment="" manufacturing.="" these="" wastewaters="" often="" are="" commingled="" with="" wastewaters="" from="" the="" manufacture="" of="" other="" dyes="" and="" pigments.="" as="" a="" result,="" the="" wastewater="" treatment="" sludges="" typically="" are="" managed="" also="" as="" a="" commingled="" wastestream="" from="" the="" production="" of="" triarylmethane="" and="" any="" other="" dyes="" or="" pigments="" manufactured="" at="" the="" site.="" based="" on="" the="" rcra="" section="" 3007="" questionnaire="" data,="" the="" 1991="" volume="" reported="" by="" the="" industry="" for="" this="" wastestream="" is="" 1,404="" metric="" tons.="" wastewater="" treatment="" sludge="" from="" the="" production="" of="" triarylmethane="" dyes="" and="" pigments="" is="" generated="" at="" only="" five="" facilities.="" the="" agency's="" sampling="" program,="" which="" was="" conducted="" in="" support="" of="" this="" listing="" determination,="" included="" wastewater="" treatment="" sludge="" from="" one="" of="" the="" five="" facilities="" generating="" this="" waste.="" however,="" the="" facility="" was="" not="" manufacturing="" triarylmethane="" dyes="" or="" pigments="" during="" the="" time="" of="" the="" sampling="" activities.="" therefore,="" the="" resulting="" absence="" of="" constituents="" attributable="" to="" the="" triarylmethane="" operations="" was="" not="" unexpected.="" in="" conclusion,="" based="" on="" insufficient="" characterization="" data,="" the="" agency="" proposes="" to="" defer="" a="" listing="" decision="" on="" wastewater="" treatment="" sludges="" from="" the="" production="" of="" triarylmethane="" dyes="" and="" pigments="" (excluding="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock).="" the="" agency="" is="" proposing="" to="" conduct="" additional="" sampling="" on="" this="" wastestream="" and="" will="" publish="" a="" supplemental="" notice="" with="" a="" proposed="" listing="" determination.="" b.="" wastewaters="" from="" the="" production="" of="" triarylmethane="" dyes="" and="" pigments="" (excluding="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock).="" summary="" epa="" is="" proposing="" not="" to="" list="" wastewaters="" from="" the="" production="" of="" triarylmethane="" dyes="" and="" pigments="" (excluding="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock)="" because="" the="" constituents="" in="" this="" waste="" were="" observed="" at="" concentrations="" that="" present="" low="" risk="" levels="" (i.e.,="" calculated="" at="" less="" than="" 1e-6="" for="" carcinogens="" and="" lower="" than="" 1="" hq="" for="" non-carcinogens)="" through="" ingestion="" of="" contaminated="" ground="" water,="" and="" no="" other="" hazardous="" constituents="" attributed="" to="" triarylmethane="" dye="" or="" pigment="" production="" were="" detected.="" discussion="" volume="" information="" reported="" by="" the="" industry="" in="" the="" 1992="" rcra="" section="" 3007="" questionnaire="" for="" the="" wastewater="" stream="" from="" triarylmethane="" dye="" and="" pigment="" production="" is="" not="" included="" at="" the="" present="" time="" due="" to="" business="" confidentiality="" concerns.="" wastewaters="" from="" the="" production="" of="" triarylmethane="" dyes="" and="" pigments="" (excluding="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock)="" often="" are="" commingled="" with="" wastewaters="" from="" the="" manufacture="" of="" azos="" and="" other="" dyes="" and="" pigments.="" table="" ii-8.--waste="" characterization="" and="" risk="" estimates="" wastewaters="" from="" the="" production="" of="" triarylmethane="" dyes="" and="" pigments="" (excluding="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock)="" --------------------------------------------------------------------------------------------------------------------------------------------------------="" baseline="" management="" plausible="" management="" waste="" characterization="" ------------------------------------------------------------------------------------------------------------------------="" treat="" in="" tanks*="" treat="" in="" si*="" constituents="" of="" concern="" ------------------------------------------------------------="" avg.="" high="" central="" central="" conc.="" conc.="" low="" conc.="" #="" of="" pts="" notes="" tendency="" high="" end="" tendency="" high="" end="" --------------------------------------------------------------------------------------------------------------------------------------------------------="" f.n............................="" no="" hbl.......="" .............="" no="" hbl.......="" .............="" f.n.="" .........="" .........="" 1="" of="" 3......="" 4-nitroaniline.................="" no="" hbl.......="" .............="" no="" hbl.......="" .............="" 0.016="" .........="" .........="" 1="" of="" 3......="" j="" f.n.="" (3)all="" remaining="" constituents="" were="" dropped="" following="" bounding="" on="" baseline="" management="" 4-methylphenol="" f.n.="" f.n.="" n,n'-dimethylaniline="" f.n.="" --------------------------------------------------------------------------------------------------------------------------------------------------------="" aa*="" exposure="" through="" ingestion="" of="" contaminated="" ground="" water.="" f.n.="" relevant="" data="" are="" not="" included="" at="" the="" present="" time="" due="" to="" business="" confidentiality="" concerns.="" notes:="" all="" concentrations="" are="" in="" mg/l.="" j(#)--samples="" where="" estimated="" concentrations="" are="" below="" quantitation="" limits,="" `(#)'="" indicates="" number="" of="" samples="" that="" are="" `j'="" values.="" information="" on="" the="" percentage="" of="" these="" wastewaters="" currently="" pretreated="" and="" discharged="" to="" a="" potw,="" and="" on="" the="" percentage="" treated="" in="" a="" biological="" treatment="" system="" and="" discharged="" to="" a="" surface="" water="" under="" the="" npdes="" system="" is="" not="" included="" at="" the="" present="" time="" due="" to="" business="" confidentiality="" concerns.="" as="" discussed="" earlier="" under="" section="" ii.d,="" description="" of="" health="" and="" risk="" assessments,="" the="" risk="" assessment="" for="" these="" wastewaters="" was="" performed="" using="" treatment="" in="" tanks="" and="" surface="" impoundments="" as="" the="" baseline="" and="" plausible="" management="" practices,="" respectively.="" the="" agency="" believes="" that="" the="" three="" wastewater="" samples="" collected="" from="" the="" manufacture="" of="" triarylmethane="" dyes="" and="" pigments="" are="" representative="" of="" the="" industry,="" in="" part,="" because="" wastewater="" samples="" were="" collected="" from="" the="" two="" largest="" triarylmethane="" dye="" producers="" in="" the="" country.="" furthermore,="" the="" chemical="" analyses="" conducted="" on="" this="" waste="" encompassed="" the="" most="" important="" raw="" materials="" used="" in="" the="" manufacture="" of="" triarylmethane="" dyes="" and="" pigments,="" and="" these="" compounds="" were="" not="" detected="" at="" concentrations="" that="" pose="" a="" significant="" risk.="" for="" example,="" n,n-="" dimethylaniline="" is="" a="" large="" volume="" raw="" material="" used="" in="" the="" manufacture="" of="" triarylmethane="" dyes="" and="" pigment,="" and="" was="" analyzed="" using="" the="" gas="" chromatography/mass="" spectrophotometry="" analytical="" method.="" in="" addition="" to="" the="" gc/ms="" analysis,="" specific="" analyses="" were="" conducted="" in="" order="" to="" look="" for="" two="" additional="" toxic="" raw="" materials="" for="" triarylmethane="" dyes="" and="" pigments;="" chloranil="" and="" another="" raw="" material="" that="" cannot="" be="" identified="" due="" to="" business="" confidentiality="" concerns.="" as="" shown="" in="" table="" ii-8,="" n,n-="" dimethylaniline="" and="" the="" other="" raw="" material="" that="" cannot="" be="" identified="" were="" not="" found="" in="" these="" wastewaters="" at="" concentrations="" that="" pose="" a="" significant="" risk,="" and="" chloranil="" was="" not="" detected="" at="" all="" in="" the="" wastewaters.="" table="" ii-8="" presents="" eight="" constituents,="" obtained="" from="" three="" wastewater="" samples="" which="" were="" collected="" at="" three="" out="" of="" 14="" facilities="" that="" manufacture="" triarylmethane="" dyes="" or="" pigments.="" these="" eight="" compounds="" are="" the="" constituents="" that="" were="" found="" to="" be="" attributable="" to="" the="" triarylmethane="" processes,="" and="" six="" of="" the="" eight="" compounds="" were="" dropped="" following="" the="" risk="" assessment="" screening="" (see="" the="" listing="" and="" risk="" assessment="" for="" dye="" and="" pigment="" waste="" listing="" determination="" background="" documents="" for="" this="" proposed="" rule,="" located="" in="" the="" rcra="" docket="" for="" this="" rulemaking="" (see="" addresses="" section)="" for="" the="" process="" used="" in="" identifying="" attributable="" constituents="" and="" for="" the="" process="" used="" for="" dropping="" compounds="" after="" risk="" screening,="" respectively).="" because="" these="" compounds="" are="" not="" expected="" to="" bioaccumulate,="" the="" maximum="" measured="" concentrations="" of="" those="" constituents="" with="" hbls="" in="" this="" wastestream="" were="" compared="" to="" their="" hbls,="" and="" the="" ratio="" of="" concentrations="" to="" hbl="" values="" was="" less="" than="" 1,="" indicating="" that="" the="" concentrations="" of="" these="" compounds="" in="" the="" waste="" are="" not="" expected="" to="" pose="" a="" risk="" to="" human="" health="" or="" the="" environment.="" the="" two="" remaining="" constituents,="" 4-nitroaniline="" and="" a="" constituent="" that="" cannot="" be="" identified="" at="" the="" present="" time="" due="" to="" confidentiality="" concerns,="" were="" detected="" at="" low="" concentrations="" and="" do="" not="" have="" hbls="" needed="" to="" conduct="" a="" risk="" assessment.="" the="" risks="" posed="" by="" these="" two="" constituents,="" however,="" were="" assessed="" using="" surrogate="" compounds.="" neither="" of="" the="" compounds="" are="" expected="" to="" be="" potential="" carcinogens.="" furthermore,="" the="" agency="" selected="" surrogate="" compounds="" that="" are="" structurally="" similar="" to="" the="" compounds="" detected="" in="" the="" waste,="" and="" are="" estimated,="" by="" means="" of="" structural="" activity="" relationships="" (sars),="" to="" be="" more="" toxic="" than="" the="" subject="" compounds.="" nitrobenzene="" was="" selected="" as="" a="" surrogate="" for="" 4-="" nitroaniline.="" surrogate="" information="" on="" the="" second="" constituent="" cannot="" be="" included="" at="" the="" present="" time="" due="" to="" business="" confidentiality="" concerns.="" the="" ratios="" of="" concentration="" to="" hbl="" (hq)="" determined="" by="" this="" analysis="" were="" also="" less="" than="" 1,="" indicating="" that,="" if="" the="" contaminant="" concentrations="" found="" in="" the="" waste="" were="" actually="" present="" in="" drinking="" water,="" the="" risks="" posed="" by="" ingesting="" the="" drinking="" water="" would="" be="" insignificant.="" more="" detailed="" discussions="" on="" the="" risk="" assessment="" screening="" and="" surrogate="" compounds="" are="" presented="" in="" the="" dye="" and="" pigment="" listing="" support="" health="" effects="" background="" document,="" which="" is="" located="" in="" the="" rcra="" docket="" for="" this="" rulemaking="" (see="" addresses="" section).="" in="" conclusion,="" because="" the="" constituents="" in="" this="" waste="" were="" observed="" at="" concentrations="" that="" present="" low="" risk="" levels,="" and="" no="" other="" hazardous="" constituents="" attributed="" to="" triarylmethane="" dye="" or="" pigment="" production="" were="" detected,="" the="" agency="" is="" proposing="" not="" to="" list="" wastewaters="" from="" the="" manufacture="" of="" triarylmethane="" dyes="" and="" pigments="" as="" hazardous.="" 4.wastes="" from="" the="" production="" of="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock.="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock="" currently="" are="" produced="" at="" two="" domestic="" facilities.="" these="" facilities="" each="" produce="" a="" single="" product="" which="" is="" manufactured="" throughout="" the="" year="" using="" aniline="" as="" the="" major="" feedstock.="" the="" two="" processes="" are="" markedly="" different="" from="" other="" dye="" and="" pigment="" processes="" in="" the="" industry.="" most="" dye="" and="" pigment="" processes="" manufacture="" numerous="" products="" on="" a="" batch="" basis,="" using="" different="" raw="" materials="" for="" each="" product.="" the="" wastes="" generated="" from="" typical="" dye="" manufacturing="" plants="" vary="" in="" composition="" over="" time="" due="" to="" the="" constant="" changes="" in="" raw="" materials.="" in="" contrast,="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock="" are="" generated="" at="" facilities="" that="" are="" dedicated="" to="" the="" manufacture="" of="" one="" product="" continuously="" throughout="" the="" year,="" and="" use="" only="" two="" raw="" materials,="" aniline="" and="" formaldehyde,="" at="" the="" site.="" in="" addition,="" aniline="" is="" used="" in="" excess="" in="" the="" process.="" these="" differences="" have="" a="" significant="" impact="" on="" the="" compositions="" of="" the="" waste.="" such="" wastes="" were="" expected,="" and="" found,="" to="" contain="" high="" concentrations="" of="" aniline.="" the="" listing="" background="" document,="" found="" in="" the="" rcra="" docket="" (see="" addresses="" section)="" for="" this="" proposed="" rulemaking,="" contains="" details="" on="" the="" process="" for="" manufacturing="" triarylmethane="" (tam)="" pigments="" using="" aniline="" as="" a="" feedstock.="" a.="" wastewater="" treatment="" sludge="" from="" the="" production="" of="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock.="" summary="" the="" agency="" is="" proposing="" not="" to="" list="" as="" hazardous="" wastewater="" treatment="" sludges="" from="" the="" production="" of="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock.="" if="" this="" wastestream="" were="" managed="" by="" disposal="" in="" a="" municipal="" landfill="" (the="" plausible="" management="" scenario="" used="" for="" other="" wastewater="" treatment="" sludges),="" it="" would="" meet="" the="" criteria="" set="" out="" at="" 40="" cfr="" 261.11(a)(3)="" for="" listing="" a="" waste="" as="" hazardous="" and="" would="" be="" capable="" of="" posing="" a="" substantial="" present="" or="" potential="" hazard="" to="" human="" health="" or="" the="" environment.="" however,="" as="" discussed="" in="" section="" ii.d,="" description="" of="" health="" and="" risk="" assessments,="" the="" agency="" has="" determined="" that="" management="" in="" a="" municipal="" landfill="" is="" not="" plausible="" for="" this="" wastestream.="" despite="" this="" determination,="" for="" comparison="" purposes="" the="" agency="" calculated="" the="" risks="" associated="" with="" disposal="" in="" a="" municipal="" landfill="" and="" with="" diposal="" in="" an="" on-site="" boiler.="" if,="" based="" on="" comments,="" the="" agency="" determines="" that="" it="" is="" not="" reasonable="" to="" use="" fuel="" blending="" as="" the="" plausible="" management="" scenario,="" the="" agency="" probably="" would="" determine="" that="" plausible="" management="" is="" disposal="" in="" a="" municipal="" landfill="" for="" the="" ground-water="" pathway,="" and="" is="" disposal="" in="" an="" on-site="" boiler="" for="" the="" air="" pathway.="" disposal="" in="" an="" on-site="" monofill,="" which="" was="" established="" as="" the="" plausible="" management="" scenario="" for="" other="" wastewater="" treatment="" sludges="" (i.e.,="" k162="" and="" k164),="" is="" not="" a="" practical="" option="" for="" this="" wastestream="" due="" to="" its="" low="" volume="" relative="" to="" the="" capacity="" of="" a="" monofill,="" and="" so="" is="" not="" feasible="" economically.="" based="" on="" ingestion="" of="" contaminated="" ground="" water="" due="" to="" releases="" from="" a="" municipal="" landfill,="" epa="" calculated="" high-end="" individual="" cancer-="" risk="" levels="" of="" 1e-4="" and="" 8e-5="" for="" the="" constituents="" benzidine="" and="" aniline,="" respectively.="" the="" coeluting="" compounds="" 1,2-diphenylhydrazine="" and="" azobenzene="" are="" calculated="" to="" pose="" risks="" between="" 1e-6="" and="" 1e-5.="" therefore,="" the="" combined="" carcinogenic="" risk="" for="" multiple="" co-existing="" constituents="" in="" this="" wastestream="" would="" be="" 2e-4,="" assuming="" disposal="" in="" a="" landfill.="" however,="" the="" risks="" associated="" with="" the="" current="" and="" plausible="" management="" practice,="" blending="" with="" non-hazardous="" fuel,="" are="" insignificant="" for="" any="" constituent.="" thus,="" the="" agency="" is="" proposing="" not="" to="" list="" it="" as="" hazardous.="" discussion="" wastewater="" treatment="" sludge="" from="" the="" production="" of="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock="" currently="" is="" generated="" at="" only="" one="" facility.="" this="" waste="" is="" generated="" from="" a="" filter="" press="" that="" is="" used="" as="" part="" of="" the="" wastewater="" pretreatment="" system.="" the="" waste="" is="" generated="" at="" a="" rate="" of="" approximately="" 18="" metric="" tons="" per="" year.="" epa="" has="" summarized="" the="" risk="" projections="" associated="" with="" this="" sludge="" in="" table="" ii-9.="" the="" data="" presented="" in="" this="" table="" represent="" one="" sample="" from="" one="" facility.="" unlike="" earlier="" wastestreams,="" health="" benchmarks="" exist="" for="" all="" the="" contaminants="" detected="" in="" this="" wastestream="" (with="" the="" exception="" of="" one="" coeluting="" compound,="" which="" is="" discussed="" later="" in="" this="" section).="" additional="" compounds="" which="" do="" have="" health="" benchmarks,="" however,="" have="" been="" identified="" in="" these="" wastes,="" but="" were="" dropped="" from="" further="" consideration="" following="" the="" risk="" screening.="" the="" complete="" list="" of="" compounds="" found="" in="" this="" and="" other="" wastestreams="" is="" presented="" in="" the="" listing="" background="" document="" for="" this="" proposed="" rule,="" which="" is="" located="" in="" the="" rcra="" docket="" for="" this="" rulemaking="" (see="" addresses="" section).="" details="" on="" the="" risk="" assessment="" are="" provided="" in="" section="" ii.d="" of="" this="" preamble,="" description="" of="" health="" and="" risk="" assessments,="" and="" in="" the="" listing="" background="" document="" for="" this="" proposed="" rule,="" located="" in="" the="" rcra="" docket="" for="" this="" rulemaking="" (see="" addresses="" section).="" table="" ii-9.--waste="" characterization="" and="" risk="" estimates="" wastewater="" treatment="" sludge="" from="" the="" production="" of="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock="" --------------------------------------------------------------------------------------------------------------------------------------------------------="" plausible="" management="" other="" management="" waste="" characterization="" ---------------------------------------------------------------------------------------------------------------------------------------="" constituents="" of="" off-site="" non-haz="" fuel="" blending**="" on-site="" boiler**="" municipal="" landfill***="" concern="" ------------------------------------------------------------------------------------="" avg.="" high="" low="" central="" central="" conc.="" conc.="" conc.="" #="" of="" pts="" notes="" central="" tendency="" high="" end="" tendency="" high="" end="" tendency="" high="" end="" --------------------------------------------------------------------------------------------------------------------------------------------------------="" 1,2-diphenyl-="" insignificant="" ................="" risk=""><1e-6 risk=""><1e-6 risk="5E-6" risk="2E-5" 370(j)="" 1="" of="" 1....="" j="" hydrazine/="" risk="" for="" any="" azoben-="" zene*.="" constituent.="" aniline.........="" ................="" ................=""><1><1 risk="2E-5" risk="8E-5" 31000="" 1="" of="" 1....="" benzidine.......="" ................="" ................="" risk=""><1e-6 risk=""><1e-6 risk="2E-5" risk="1E-4" 6.3="" 1="" of="" 1....="" ..........="" combined="" insignificant="" ................="" risk=""><1e-6 risk=""><1e-6 risk="5E-5" risk="2E-4" carcinogen="" risk.="" risk="" for="" any="" constituent.="" --------------------------------------------------------------------------------------------------------------------------------------------------------="" *risk="" numbers="" based="" on="" hbl="" for="" 1,2-diphenylhydrazine.="" **inhalation="" exposure="" through="" air="" pathway.="" ***exposure="" through="" ingestion="" of="" contaminated="" ground="" water.="" notes:="" all="" concentrations="" are="" in="" mg/l.="" j(#)--samples="" where="" estimated="" concentrations="" are="" below="" quantitation="" limits,="" `(#)'="" indicates="" number="" of="" samples="" that="" are="" `j'="" values.="" as="" shown="" in="" table="" ii-9,="" benzidine="" is="" present="" in="" this="" wastestream="" at="" concentrations="" that="" pose="" a="" substantial="" risk="" to="" human="" health="" and="" the="" environment="" (i.e.,="" equal="" to="" or="" greater="" than="" 1e-5="" for="" carcinogens)="" for="" the="" municipal="" landfill="" management="" scenario.="" benzidine="" was="" found="" to="" be="" present="" in="" several="" wastestreams="" from="" the="" manufacture="" of="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock,="" including="" wastewaters="" from="" both="" facilities="" that="" manufacture="" these="" pigments.="" the="" agency="" believes="" that="" benzidine="" is="" either="" a="" raw="" material="" contaminant="" or="" a="" reaction="" by-product="" from="" the="" process.="" large="" quantities="" of="" aniline,="" typically="" in="" excess,="" are="" used="" as="" a="" raw="" material="" to="" this="" process.="" as="" a="" result,="" this="" wastestream="" was="" found="" to="" contain="" over="" three="" percent="" aniline.="" the="" calculated="" high-end="" individual="" cancer-risk="" level="" for="" aniline="" is="" 8e-5="" for="" the="" landfill="" scenario.="" in="" addition="" to="" benzidine="" and="" aniline,="" the="" waste="" was="" found="" to="" contain="" two="" other="" hazardous="" constituents="" that="" are="" believed="" to="" be="" by-="" products="" of="" the="" reaction="" and="" pose="" a="" significant="" risk="" at="" the="" concentrations="" detected="" for="" the="" municipal="" landfill="" management="" scenario.="" two="" additional="" compounds="" presented="" in="" table="" ii-9,="" 1,2-="" diphenylhydrazine="" and="" azobenzene,="" coelute="" on="" the="" mass="" spectrum="" (see="" section="" ii.d,="" description="" of="" health="" and="" risk="" assessments,="" for="" a="" discussion="" on="" the="" agency's="" approach="" to="" risk="" assessment="" for="" coeluting="" compounds).="" both="" compounds="" are="" likely="" oxidation="" products="" of="" aniline,="" and="" may="" be="" present="" in="" the="" waste="" as="" reaction="" by-products.="" in="" addition="" to="" the="" uncertainty="" in="" establishing="" concentrations="" for="" each="" of="" the="" two="" compounds,="" the="" chemical="" pathway="" from="" aniline="" to="" these="" oxidation="" products="" suggests="" that="" either="" contaminant="" may="" be="" present="" at="" all="" or="" part="" of="" the="" concentration="" detected.="" the="" agency="" conducted="" the="" risk="" assessment="" using="" the="" health-based="" levels="" for="" 1,2-diphenylhydrazine="" and="" azobenzene,="" independently.="" for="" disposal="" in="" a="" municipal="" landfill,="" the="" calculated="" high-end="" individual="" cancer-risk="" level="" for="" these="" coeluting="" compounds,="" based="" on="" the="" toxicity="" of="" 1,2-diphenylhydrazine,="" is="" 2e-5.="" in="" addition="" to="" assessing="" the="" risks="" associated="" with="" the="" individual="" constituents="" found="" in="" the="" waste,="" the="" agency="" considers="" the="" combined="" risk="" of="" constituents="" that="" co-exist="" in="" the="" wastestream.="" in="" the="" case="" of="" this="" wastewater="" treatment="" sludge,="" all="" of="" the="" constituents="" discussed="" above="" (i.e.,="" aniline,="" benzidine,="" and="" 1,2-diphenylhydrazine/azobenzene)="" are="" believed="" to="" co-exist="" in="" the="" wastestream.="" the="" processes="" that="" produce="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock="" are="" operated="" continuously="" all="" year.="" as="" a="" result,="" the="" constituents="" detected="" in="" the="" wastestream="" are="" likely="" to="" be="" present="" simultaneously="" in="" the="" waste.="" therefore,="" the="" combined="" calculated="" risk="" of="" these="" individual="" constituents,="" for="" the="" municipal="" landfill="" scenario="" would="" be="" 2e-4="" at="" the="" high="" end.="" however,="" the="" risks="" associated="" with="" the="" current="" and="" plausible="" management="" practice="" for="" this="" wastestream="" (blending="" with="" non-hazardous="" fuel="" for="" combustion)="" are="" insignificant.="" as="" discussed="" in="" section="" ii.d,="" description="" of="" health="" and="" risk="" assessments,="" the="" agency="" believes="" that="" the="" fuel="" blending="" will="" continue.="" the="" relatively="" high="" organic="" content="" of="" the="" waste="" gives="" the="" material="" value="" as="" a="" fuel="" ingredient="" and,="" therefore,="" generators="" of="" this="" waste="" have="" an="" economic="" incentive="" to="" continue="" fuel="" blending.="" therefore,="" the="" agency="" is="" proposing="" not="" to="" list="" the="" wastestream="" as="" hazardous.="" if="" the="" npdes="" program="" requirements="" were="" to="" change="" (i.e.,="" become="" more="" stringent)="" then="" those="" triarylmethane="" pigment="" producers="" that="" currently="" do="" not="" generate="" a="" sludge="" could="" be="" forced="" to="" generate="" a="" sludge="" due="" to="" their="" efforts="" to="" meet="" new="" npdes="" requirements.="" in="" that="" case,="" the="" plausible="" management="" scenario="" would="" change,="" and="" other="" practices,="" such="" as="" landfilling,="" would="" become="" possible.="" the="" agency="" may="" reopen="" this="" listing="" decision="" should="" this="" occur,="" and="" will="" use="" the="" risk="" levels="" associated="" with="" this="" management="" scenario="" to="" make="" a="" revised="" listing="" determination.="" b.="" wastewaters="" from="" the="" production="" of="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock.="" summary="" the="" agency="" is="" proposing="" not="" to="" list="" as="" hazardous="" wastewaters="" from="" the="" production="" of="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock.="" as="" shown="" in="" table="" ii-10,="" these="" wastewaters="" contain="" an="" average="" aniline="" concentration="" of="" 200="" ppm.="" in="" addition,="" the="" wastewaters="" contain="" the="" same="" hazardous="" by-products="" found="" in="" the="" wastewater="" treatment="" sludge.="" although="" this="" wastestream,="" if="" managed="" in="" surface="" impoundments,="" would="" meet="" the="" criteria="" set="" out="" in="" 40="" cfr="" 261.11(a)(3)="" for="" listing="" a="" waste="" as="" hazardous="" and="" would="" be="" capable="" of="" posing="" a="" substantial="" present="" or="" potential="" risk="" to="" human="" health="" or="" the="" environment="" if="" released="" into="" the="" environment,="" the="" agency="" has="" determined="" that="" management="" in="" surface="" impoundments="" is="" not="" plausible="" for="" this="" wastestream.="" the="" agency="" believes="" this="" because="" 100%="" of="" this="" wastestream="" is="" managed="" in="" exempt="" tanks.="" the="" agency="" has="" no="" reason="" to="" believe="" that="" this="" management="" practice="" will="" change.="" risk="" associated="" with="" treatment="" in="" tanks="" is="" insignificant="" and,="" thus,="" the="" agency="" is="" proposing="" not="" to="" list="" this="" waste="" as="" hazardous.="" however,="" for="" comparison="" purposes,="" the="" agency="" has="" calculated="" the="" risks="" associated="" with="" disposal="" of="" this="" wastestream="" in="" a="" surface="" impoundment.="" if,="" based="" on="" comments,="" the="" agency="" determines="" that="" it="" is="" not="" reasonable="" to="" assume="" that="" management="" in="" tanks="" is="" the="" correct="" plausible="" management="" scenario,="" the="" agency="" probably="" would="" determine="" that="" management="" in="" a="" surface="" impoundment="" is="" the="" appropriate="" plausible="" management="" scenario.="" discussion="" these="" wastewaters="" are="" generated="" from="" filtrations="" of="" process="" intermediates="" and="" products,="" flushing="" operations,="" equipment="" washdowns,="" floor="" washings,="" and="" process="" operations.="" based="" on="" response="" data="" from="" the="" 1991="" rcra="" section="" 3007="" questionnaire,="" a="" total="" of="" 757,080="" metric="" tons,="" or="" 0.4="" million="" gallons="" per="" day,="" of="" wastewater="" from="" the="" production="" of="" triarylmethane="" (tam)="" pigments="" is="" generated.="" information="" on="" generation="" relevant="" to="" this="" discussion="" is="" not="" included="" at="" the="" present="" time="" due="" to="" business="" confidentiality="" concerns.="" all="" of="" the="" wastewaters="" generated="" from="" tam="" pigment="" production="" (using="" aniline="" as="" a="" feedstock)="" are="" treated="" in="" tanks="" prior="" to="" discharge="" to="" a="" potw.="" the="" data="" presented="" in="" table="" ii-="" 10="" represent="" three="" samples="" collected="" from="" two="" tam="" pigment-manufacturing="" facilities.="" table="" ii-10.--waste="" characterization="" and="" risk="" estimates="" wastewaters="" from="" the="" production="" of="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock="" ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------="" plausible="" management="" other="" management="" waste="" characterization="" --------------------------------------------------------------------------------------------------------------------------------------------------------------------="" treat="" in="" tanks**="" treat="" in="" si***="" treat="" in="" si***="" constituents="" of="" concern="" -----------------------------------------------------------------------------------------------------------="" avg.="" high="" low="" central="" central="" conc.="" conc.="" conc.="" #="" of="" pts="" notes="" central="" tendency="" high="" end="" tendency="" high="" end="" tendency="" high="" end="" ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------="" 1,2-dipheny-="" lhydrazine/="" insignificant="" risks="" for="" ..........................="" ..........="" ..........="" risk="5E-6" r="1E-5" f.n.="" f.n.="" 0.093="" f.n.="" j(2)="" azoben-="" zene*.="" any="" constituent.="" (j)="" aniline....................="" ..........................="" ..........................="" ..........="" ..........="" risk="7E-5" r="1E-4" f.n.="" f.n.="" 108="" f.n.="" benzidine..................="" ..........................="" ..........................="" ..........="" ..........="" risk="1E-4" r="3E-4" f.n.="" f.n.="" 0.006="" f.n.="" ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------="" combined="" carcinogenic="" risk.="" ..........................="" ..........................="" ..........="" ..........="" risk="2E-4" r="5E-4" ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------="" *risk="" numbers="" based="" on="" hbl="" for="" 1,2-diphenylhydrazine.="" **inhalation="" exposure="" through="" air="" pathway.="" ***exposure="" through="" ingestion="" of="" ground="" water.="" f.n.="" relevant="" data="" are="" not="" included="" at="" the="" present="" time="" due="" to="" business="" confidentiality="" concerns.="" notes:="" all="" concentrations="" are="" in="" mg/l.="" j(#)--samples="" where="" estimated="" concentrations="" are="" below="" quantitation="" limits,="" `(#)'="" indicates="" number="" of="" samples="" that="" are="" `j'="" values.="" as="" discussed="" earlier="" under="" section="" ii.d,="" description="" of="" health="" and="" risk="" assessments,="" the="" plausible="" management="" scenario="" selected="" for="" wastewaters="" usually="" is="" treatment="" in="" surface="" impoundments.="" the="" risks="" associated="" with="" disposing="" these="" wastewaters="" in="" surface="" impoundments="" would="" be="" very="" high.="" two="" hazardous="" constituents="" (aniline="" and="" benzidine)="" are="" present="" in="" the="" waste="" at="" concentrations="" that="" would="" pose="" substantial="" risks="" to="" human="" health="" and="" the="" environment="" (i.e.,="" greater="" than="" 1e-4="" for="" carcinogens)="" for="" treatment="" in="" a="" surface="" impoundment.="" large="" quantities="" of="" aniline,="" used="" in="" excess,="" are="" used="" as="" a="" raw="" material="" in="" this="" process.="" as="" a="" result,="" very="" high="" concentrations="" of="" aniline="" are="" present="" in="" the="" process="" waters.="" even="" after="" recovery="" operations,="" epa="" found="" high="" concentrations="" of="" aniline="" (in="" this="" case,="" an="" average="" of="" 200="" ppm)="" remaining="" in="" the="" wastewater="" effluent="" discharged="" to="" the="" potw.="" benzidine="" was="" found="" to="" be="" present="" in="" several="" wastestreams="" from="" the="" manufacture="" of="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock,="" and="" is="" believed="" to="" be="" either="" a="" raw="" material="" contaminant="" or="" a="" reaction="" by-product.="" the="" risks="" posed="" by="" benzidine="" at="" the="" concentrations="" present="" in="" these="" wastewaters="" are="" 3e-4,="" using="" a="" surface="" impoundment="" management="" scenario.="" the="" coeluting="" constituents,="" 1,2-diphenylhydrazine="" and="" azobenzene,="" which="" are="" likely="" by-products="" arising="" from="" the="" oxidation="" of="" aniline="" are="" present="" in="" the="" waste="" at="" a="" concentration="" resulting="" in="" a="" calculated="" risk="" level="" of="" 1e-5,="" based="" on="" the="" toxicity="" of="" 1,2-diphenylhydrazine="" (see="" section="" ii.d,="" description="" of="" health="" and="" risk="" assessments,="" for="" a="" discussion="" on="" the="" agency's="" approach="" to="" risk="" assessment="" for="" coeluting="" compounds).="" the="" mass="" spectrum="" representing="" these="" two="" coeluting="" compounds="" was="" identified="" in="" all="" three="" wastewater="" samples="" collected="" from="" triarylmethane="" pigment="" operations.="" however,="" based="" on="" the="" insignificant="" risks="" associated="" with="" the="" current="" and="" plausible="" management="" practice="" for="" this="" wastestream="" (treatment="" in="" tanks),="" epa="" is="" proposing="" not="" to="" list="" wastewaters="" from="" the="" production="" of="" tam="" pigments="" as="" hazardous.="" although="" this="" wastestream="" would="" be="" hazardous="" if="" used="" for="" spray="" irrigation="" or="" handled="" in="" surface="" impoundments,="" the="" agency="" does="" not="" believe="" that="" such="" management="" is="" plausible.="" the="" facilities="" generating="" the="" wastewater="" already="" are="" 100%="" invested="" in="" treating="" the="" waste="" in="" tanks="" prior="" to="" sending="" it="" to="" a="" potw.="" in="" addition,="" this="" is="" not="" a="" strongly="" expanding="" segment="" of="" the="" industry,="" so="" the="" agency="" does="" not="" anticipate="" more="" facilities="" starting="" up="" similar="" operations.="" further,="" there="" is="" a="" general="" bias="" under="" most="" state="" industrial="" waste="" programs="" against="" allowing="" surface="" impoundments="" to="" be="" built.="" thus,="" based="" on="" the="" risk="" associated="" with="" treatment="" in="" tanks,="" the="" agency="" is="" proposing="" not="" to="" list="" this="" wastestream="" as="" hazardous.="" c.="" still="" bottoms="" or="" heavy="" ends="" from="" the="" production="" of="" triarylmethane="" dyes="" or="" pigments="" (k166).="" summary="" the="" agency="" is="" proposing="" to="" list="" still="" bottoms="" or="" heavy="" ends="" from="" the="" production="" of="" triarylmethane="" dyes="" or="" pigments="" as="" hazardous.="" this="" wastestream="" meets="" the="" criteria="" set="" out="" at="" 40="" cfr="" 261.11(a)(3)="" for="" listing="" a="" waste="" as="" hazardous="" and="" is="" capable="" of="" posing="" a="" substantial="" present="" or="" potential="" risk="" to="" human="" health="" or="" the="" environment.="" based="" on="" ingestion="" of="" contaminated="" ground="" water,="" epa="" calculated="" high-end="" individual="" risk="" levels="" (greater="" than="" 1e-4)="" for="" carcinogens="" under="" both="" the="" baseline="" and="" plausible="" management="" scenarios.="" two="" carcinogens="" pose="" high-end="" risks="" exceeding="" 9e-3="" for="" the="" plausible="" management="" scenario="" of="" disposal="" in="" an="" on-site="" monofill.="" these="" two="" constituents="" pose="" very="" high="" levels="" of="" risk="" (greater="" than="" 1e-3)="" for="" the="" baseline="" management="" practice="" of="" disposal="" in="" a="" municipal="" landfill.="" in="" addition,="" one="" of="" these="" constituents="" has="" an="" hq="" of="" 6="" for="" the="" air="" pathway="" associated="" with="" management="" in="" an="" on-site="" boiler,="" a="" practice="" which="" is="" both="" a="" baseline="" management="" practice="" and="" a="" plausible="" management="" scenario.="" discussion="" this="" wastestream="" includes="" distillation="" bottoms="" from="" the="" production="" of="" triarylmethane="" dye="" and="" pigments,="" which="" are="" generated="" from="" solvent="" and="" raw="" material="" recovery="" operations="" (i.e.,="" recovery="" of="" aniline,="" dimethylaniline,="" or="" other="" solvents).="" table="" ii-11.--waste="" characterization="" and="" risk="" estimates="" k166--still="" bottoms="" or="" heavy="" ends="" from="" the="" production="" of="" triarylmethane="" pigments="" using="" aniline="" as="" a="" feedstock="" --------------------------------------------------------------------------------------------------------------------------------------------------------="" baseline="" management="" plausible="" management="" waste="" characterization="" --------------------------------------------------------------------------------------------------------------------------------------="" constituents="" of="" on-site="" boiler="" municipal="" landfill="" on-site="" boiler="" on-site="" monofill="" concern="" ----------------------------------------------------------------------------------------="" avg.="" high="" low="" central="" central="" central="" central="" conc.="" conc.="" conc.="" #="" of="" pts="" notes="" tend.="" high="" end="" tend.="" high="" end="" tend.="" high="" end="" tend.="" high="" end="" --------------------------------------------------------------------------------------------------------------------------------------------------------="" 1,2-dip-="" henyl-="" r="2E-6" r="6E-5" r="6E-4" r="2E-3" r="7E-6" r="1E-5" r="">9E-3     R>9E-3        f.n.     f.n.     1700  2 of 2..          
     hydra- zine/ Azo-                                                                                                                                      
      ben- zene*.                                                                                                                                           
    Aniline..........  HQ<1 hq="6" r="2E-3" r="7E-3" hq="3" hq="6" r="">9E-3     f.n.          f.n.    19000   2 of 2                    
    N-nitro- sodi-     no air     no air     R<1e-6><1e-6 no="" air="" no="" air="" r="1E-6" r="6E-6" 580="" .......="" .......="" 1="" of="" 2..="" j="" phenyl-="" amine/="" hbl="" hbl="" hbl="" hbl="" di-="" phenyl-="" amine="" **.="" combined="" r="2E-6" r="6E-5" r="2E-3" r="9E-3" r="2E-5" r="6E-5" r="">9E-3     R>9E-3                                                  
     Carcinogen Risk.                                                                                                                                       
    --------------------------------------------------------------------------------------------------------------------------------------------------------
    *Risk numbers based on HBL for 1,2-diphenylhydrazine.                                                                                                   
    **Risk numbers based on HBL for N-nitrosodiphenylamine.                                                                                                 
                                                                                                                                                            
     f.n. Relevant data are not included at the present time due to business confidentiality concerns.                                                      
                                                                                                                                                            
     Notes:                                                                                                                                                 
    All concentrations are in mg/kg.                                                                                                                        
    J(#)--Samples where estimated concentrations are below quantitation limits, `(#)' indicates number of samples that are `J' values.                      
    
        Information relevant to this discussion is not included at the 
    present time due to business confidentiality concerns.
        Process waters from the manufacture of triarylmethane dyes and 
    pigments containing high levels of aniline or other raw materials and 
    solvents sometimes are sent to a distillation column for recovery of 
    the material for reuse in the process. As expected, the bottoms 
    generated from the distillation contain high concentrations of the 
    material being recovered. The concentrations of aniline present in two 
    samples collected exemplify the concentrations of solvent contaminants 
    anticipated in these wastes. Information on the concentration of 
    aniline observed is not presented at his time due to business 
    confidentiality concerns.
        Based on data from the RCRA Section 3007 Questionnaire, four 
    facilities generated a total of 1700 metric tons of this waste in 1991.
        EPA has summarized the risk projections associated with this waste 
    in Table II-11. The data presented in this table represent two samples 
    from two facilities. These samples were collected from the two largest 
    generators of this wastestream, both of which recover aniline from the 
    wastewater. One of the remaining two facilities recovers other aniline 
    derivatives (i.e., N,N- dimethylaniline and N,N-diethylaniline) that 
    are used as raw materials and solvents in the production of 
    triarylmethane dyes. The second facility recovers chlorobenzene used as 
    a solvent in the production of triarylmethane dyes and generates a 
    still bottom waste that is reported to contain 50% chlorobenzene. This 
    waste is already listed as F002, based on the use of the solvent 
    chlorobenzene. Based on an evaluation of the processes generating these 
    wastes and the contaminants reported to be present by industry, the 
    Agency believes the risks posed are similar to those assessed in Table 
    II-11. The data used to characterize these wastestreams, assess the 
    risks posed by these wastes, and make a proposed listing determination 
    on the waste grouping were obtained from the two samples collected by 
    EPA and the 1991 RCRA Section 3007 Questionnaire responses. Waste 
    management information relevant to this discussion are not included at 
    the present time due to business confidentiality concerns.
        As discussed earlier in Section II.D, Description of Health and 
    Risk Assessments, the Agency conducted the risk assessment on these 
    wastestreams using the two most widely used practices, the on-site 
    boiler and municipal landfill as the current management scenario, and 
    an on-site boiler (for the air pathway) and on-site monofill (for the 
    ground-water pathway) as the plausible management scenario.
        The risk posed by the presence of aniline in the concentrations 
    found in the waste is estimated to be very high (i.e., greater than 9E-
    3 for the ground-water pathway, and HQ=6 for the air pathway). Due to 
    the imperfect nature of any recovery process, it is not unexpected that 
    large quantities of aniline, or any other raw material or solvent being 
    recovered, would be present in these still bottoms. Aniline was found 
    in very high concentrations (i.e., the low concentration was 1.9%) in 
    both distillation bottom samples collected from triarylmethane pigment 
    production. Information on the high concentration value is not included 
    at the present time due to business confidentiality concerns.
        In addition to aniline, the two sets of coeluting constituents 
    present in the wastewater treatment sludge and wastewaters from these 
    operations (i.e., 1,2-diphenylhydrazine and azobenzene, and N-
    nitrosodiphenylamine and diphenylamine) also are present in the 
    distillation bottoms (K166). These compounds are all likely by-products 
    arising from the oxidation of aniline. The MS curve representing 1,2-
    diphenylhydrazine and azobenzene was identified in both distillation 
    bottom samples collected from triarylmethane pigment operations. For 
    the reasons discussed in Section II.D, the Agency conducted the risk 
    assessment for these coeluting compounds independently. The resulting 
    high-end individual cancer-risk level for this first set of coeluting 
    compounds is greater than 9E-3. Likewise, the risk assessment for N-
    nitrosodiphenylamine and diphenylamine was conducted independently, as 
    discussed in Section II.D. The resulting high-end individual cancer-
    risk level for this second set of coeluting compounds is 6E-6.
        In addition to assessing the risks associated with the individual 
    constituents found in the waste, the Agency considers the combined 
    risks of constituents that co-exist in the wastestream. In the case of 
    still bottoms from the production of triarylmethane dyes and pigments, 
    all of the constituents are believed to co-exist in the wastestream. 
    The distillation columns generating this residual process the same 
    wastestream with each dye or pigment batch. As a result, the 
    constituents detected are likely to be present simultaneously in the 
    waste. The risk of each individual constituent is high, and the 
    combined risks of these constituents are very high (greater than 9E-3 
    for the ground-water pathway and 6E-5 for the air pathway), both of 
    which were considered in making this listing determination.
        In addition to the very high risks posed by the plausible 
    management practice (on-site boiler for the air pathway and on-site 
    monofill for the ground-water pathway), the risks posed by the baseline 
    management practice (on-site boiler for the air pathway and municipal 
    landfill for the ground-water pathway) are also very high. 
    Specifically, the risks posed by the current management practices are 
    greater than 9E-3 for the ground-water pathway, and 6E-5 (carcinogens) 
    and HQ=6 (non-carcinogens) for the air pathway.
        In summary, the calculated risks associated with managing these 
    still bottoms in on-site boilers, municipal landfills, and on-site 
    monofills are all very high, based on each of the individual hazardous 
    constituents in the wastestream and the combined risks due to 
    carcinogens found in the wastestream as a whole. Therefore, based on 
    the risks associated with both current management and plausible 
    management practices for this waste, EPA is proposing to list as 
    hazardous still bottoms or heavy ends from the production of 
    triarylmethane dyes or pigments, designated EPA Hazardous Waste Number 
    K166.
        For the reasons stated above, the Agency is proposing to add the 
    following constituents to Appendix VII to Part 261--Basis for Listing: 
    1,2-diphenylhydrazine, azobenzene, aniline, diphenylamine, and N-
    nitrosodiphenylamine.
        In addition, azobenzene and N-nitrosodiphenylamine are proposed to 
    be added to Appendix VIII to Part 261--Hazardous Constituents.
        5.Wastes from the production of anthraquinone dyes and pigments.
        a. Wastewater treatment sludge from the production of anthraquinone 
    dyes and pigments.
    Summary
        EPA is proposing to defer the proposed listing determination for 
    wastewater treatment sludges from the production of anthraquinone dyes 
    and pigments at this time. Based on analysis of the sludge samples 
    collected by the Agency, no constituents attributable to anthraquinone 
    processes were detected. However, data supplied by industry indicate 
    the presence of two constituents on the target analyte list for which 
    no health-based levels and no adequate surrogates exist. Based on this 
    discrepancy and the need to identify surrogates for risk analysis, the 
    Agency believes a deferral is appropriate for this wastestream.
    Discussion
        This sludge is generated from the treatment of wastewaters from 
    anthraquinone dye and pigment manufacturing. Volume information 
    reported by industry in the 1992 RCRA 3007 Questionnaire data is not 
    included at the present time due to business confidentiality concerns.
        Wastewater treatment sludge from the production of anthraquinone 
    dyes and pigments is generated at 11 facilities. Sludge generated from 
    9 of the 11 facilities, which represents over 98% of the anthraquinone 
    dye and pigment production volume, is commingled with wastewater 
    treatment sludge from the production of azo pigments and/or dyes. Over 
    98% of the commingled sludge currently is managed in municipal 
    landfills or is disposed in on-site monofills. Small fractions of the 
    commingled sludge are managed under Subtitle C. Waste management and 
    waste volume information relevant to this discussion is not included at 
    the present time due to business confidentiality concerns.
        Of the 11 facilities that generate this waste, the Agency collected 
    samples from the three largest contributors to the wastestream and from 
    one small contributor. Several compounds used in anthraquinone dye or 
    pigment operations were expected to be present in the waste, based on 
    facility production schedules, and were not detected. In addition, 
    analysis of these samples did not produce any other contaminants 
    attributable to anthraquinone dye or pigment operations (refer to the 
    Background Document for this rulemaking located in the RCRA Docket for 
    this rule (see ADDRESSES section) for the methodology used in 
    identifying contaminants attributable to a process).
        Several compounds used in the manufacture of anthraquinone dyes and 
    pigments were dropped from the Agency's target analyte list for dye and 
    pigment wastes, due to the absence of any health effects information 
    and because of low usage rates (i.e., the compound was used at only 1 
    or 2 facilities). Examples of anthraquinone-related compounds dropped 
    from the target analyte list for these reasons include: 1-
    chloroanthraquinone, 1,4- dihydroxyanthraquinone-2-sulfonic acid, 1-
    amino-2-chloro-4- hydroxyanthraquinone, and 1-amino-4-bromo-2-
    anthraquinonesulfonic acid.
        As stated above, the Agency's analysis of wastewater treatment 
    sludge samples collected from anthraquinone dye and pigment operations 
    did not produce any contaminants attributable to anthraquinone dye or 
    pigment operations. However, industry data submitted on 11 sludge 
    samples confirmed the presence of two target analytes, 1-
    aminoanthraquinone, and leucoquinizarine, at average concentrations of 
    1.5, and 1.4 ppm, respectively. Each of the two analytes was detected 
    in three of the 11 samples.
        The Agency did not find HBLs for either of the two compounds 
    detected in this wastestream, 1-aminoanthraquinone and 
    leucoquinizarine. In addition, the Agency was not able to identify any 
    appropriate surrogate compounds to represent the toxicity of these 
    compounds. If one or both of these compounds are potential carcinogens 
    and behave in a similar manner to the potential carcinogen, 1-amino-2-
    methyl-anthraquinone, then the risk posed by the presence of the 
    compounds in the waste would need to be examined further. The Agency is 
    concerned about using this limited surrogate information as a basis for 
    listing this waste as hazardous.
        In summary, the Agency is proposing to defer a listing 
    determination for wastewater treatment sludge from the manufacture of 
    anthraquinone dyes and pigments at this time, and is requesting data on 
    the toxicity of 1-aminoanthraquinone and leucoquinizarine or 
    information on suitable surrogates for these compounds. EPA also would 
    be interested in submission of further characterization data. EPA will 
    evaluate carefully all public comments and information received in 
    response to this notice. Based on comments or data received, the 
    Agency, rather than deferring, may choose to promulgate a final 
    determination to either list or not to list this waste as hazardous 
    under RCRA.
        b. Wastewaters from the production of anthraquinone dyes and 
    pigments.
    Summary
        EPA is proposing not to list wastewaters from the production of 
    anthraquinone dyes and pigments as hazardous. This wastestream is not 
    considered to pose significant risks to human health and the 
    environment, based on the analysis of samples of the waste. Several 
    compounds used in the manufacture of anthraquinone dyes and pigments 
    were expected to be present in the waste but were not detected. Only 
    one compound attributable to anthraquinone processes, 3-
    aminoacetanilide, was detected in the waste, at low concentrations. 
    Health effects information on this constituent does not currently 
    exist, and risk estimates conducted using methylenephenylenediamine as 
    a surrogate indicate no significant risks.
    Discussion
        Based on response data from the RCRA Section 3007 Questionnaire, 
    the 1991 volume reported by the industry for wastewaters from 
    anthraquinone dye and pigment production was 3,988,166 metric tons, or 
    approximately 2.9 million gallons per day, generated at 25 facilities. 
    Most of the wastewater currently is treated and discharged to a surface 
    water under the NPDES system; the remainder is discharged to a POTW 
    (with 5% pretreated prior to discharge). Additional information on 
    volumes and waste managment is not included at the present time due to 
    business confidentiality concerns.
        Of the 25 facilities that generate this waste, the Agency collected 
    a total of seven samples from the four largest contributors to the 
    wastestream and from one small contributor. Information relevant to 
    this discussion is not included at the present time due to business 
    confidentiality concerns.
        As stated above, several compounds used in anthraquinone dye and 
    pigment operations were expected to be present in the waste, based on 
    facility production schedules, and were not detected. In addition, only 
    one compound attributable to anthraquinone dye and pigment production 
    was detected in the waste (refer to the Background Document for this 
    rulemaking located in the RCRA Docket for this rule (see ADDRESSES 
    section) for the methodology used in identifying contaminants 
    attributable to a process). This compound, 3-aminoacetanilide, was 
    present in five of the seven samples collected, at an average 
    concentration of 0.15 ppm. However, health effects information needed 
    to assess the risk posed by this constituent does not currently exist. 
    In order to estimate the potential risk from 3-aminoacetanilide, the 
    Agency performed a risk assessment using methylenephenylenediamine as a 
    surrogate compound. The Agency selected a surrogate compound that is 
    structurally similar to the compound detected in the waste (i.e., 3-
    aminoacetanilide), and is estimated, by means of structural activity 
    relationships (SARs), to be more toxic than the subject compound. This 
    assessment produced a groundwater concentration, prior to dilution and 
    attenuation, of 1.5 times the HBL. Thus, the concentration at the 
    receptor well, following dilution and attenuation, would be expected to 
    be less than the HBL. More detailed discussions on the risk assessment 
    screening and surrogate compounds are presented in Section II.D of this 
    preamble, Description of Health and Risk Assessments, and the Listing 
    Background Document for this proposed rule, which is located in the 
    RCRA Docket for this rulemaking (see ADDRESSES section).
        In conclusion, because the one compound attributable to 
    anthraquinone dye or pigment production detected in this waste is 
    present in low concentrations, does not have health data needed to 
    assess risk, and does not indicate a risk using surrogate toxicity 
    data, the Agency is proposing not to list wastewaters from the 
    manufacture of anthraquinone dyes and pigments as hazardous.
        6.Wastewaters from the production of FD&C colorants.
    Summary
        EPA is proposing not to list wastewaters from the production of 
    FD&C colorants as hazardous wastes. This wastestream is not considered 
    to pose significant risks to human health and the environment, based on 
    the analysis of samples of the waste. Only three constituents 
    attributable to FD&C colorant processes were detected in the waste, and 
    these do not present a risk at the concentrations observed.
    Discussion
        Based on the 1991 RCRA Section 3007 Questionnaire data, the volume 
    reported by the industry for the wastewater stream from FD&C colorant 
    production is 3,557,563 metric tons per year, or 2.6 million gallons 
    per day. Information on the percentage of these wastewaters that are 
    currently pretreated and discharged to a POTW and other waste 
    management information relevant to this discussion is not included at 
    the present time due to business confidentiality concerns.
        The Agency collected three samples of wastewaters generated from 
    FD&C operations and did not find any hazardous constituents present at 
    concentrations that pose a risk above EPA's initial risk ``level of 
    concern'' (i.e., 1E-5 for carcinogens, and HQ of 1 or greater). The 
    Agency believes that the samples of wastewaters from the manufacture of 
    FD&C colorants are representative of the industry. In fact, wastewater 
    samples were collected from the two largest-volume FD&C colorant 
    producers in the country, in addition to one smaller manufacturer.
        Several of the raw materials used in the manufacture of FD&C 
    colorants were dropped from the Agency's target analyte list for 
    analysis of dye and pigment wastes because the few existing health 
    studies on these compounds indicate that the compounds are non-toxic. 
    In addition, many of the raw materials used in the manufacture of FD&C 
    colorants are compounds that contain sulfonic acid functional groups, 
    for which analytical methods do not exist. Examples of FD&C raw 
    materials dropped from the target analyte list for these reasons 
    include p-toluidine-m-sulfonic acid, and sulfanilic acid.
        The sulfonic acid functional group imparts water solubility to a 
    compound, which generally results in lower toxicity. However, several 
    of these materials may pose a risk when present in the wastestream 
    without the sulfonic acid functional group. For example, without 
    sulfonic acid functional groups, the two compounds listed above (p-
    toluidine-m-sulfonic acid and sulfanilic acid) are represented by p-
    toluidine, and aniline, respectively. In these cases, the precursors to 
    the FD&C reactants (i.e., prior to sulfonation) remained as target 
    analytes even when the sulfonated compounds were not on the list. 
    Information relevant to this discussion is not included due to business 
    confidentiality concerns. (Refer to the Dye and Pigment Listing 
    Background Document, located in the RCRA Docket for this proposed 
    rulemaking (see ADDRESSES section), for details on the development of 
    the target analyte list.)
        From the three FD&C wastewater samples collected, the following 
    three constituents were observed that are attributable to FD&C colorant 
    production: Aniline, 3-hydroxyphenol, and phenol. During the risk 
    assessment screening, the Agency found that the three constituents 
    present in the waste (i.e., aniline, 3-hydroxyphenol, and phenol) do 
    not pose a risk at the concentrations detected. In fact, the ratios of 
    maximum measured concentration in the wastestream to the HBL were less 
    than 1 for aniline and phenol. Since there currently is no HBL 
    available for 3-hydroxyphenol, the concentration of 3-hydroxyphenol was 
    compared to that of a surrogate. 3-Hydroxyphenol is not expected to be 
    a potential carcinogen. Furthermore, the Agency selected a surrogate 
    compound that is structurally similar to the compound detected in the 
    waste, and is estimated, by means of structural activity relationships 
    (SARs), to be more toxic than the subject compound. Therefore, phenol 
    was selected as a surrogate for this 3-hydroxyphenol, and the resulting 
    ratio of concentration to HBL was also less than 1. This indicates that 
    if the contaminant concentrations found in the waste were actually 
    present in drinking water, the risks posed by ingesting the drinking 
    water would be insignificant.
        In conclusion, because the constituents in this wastestream were 
    observed at concentrations that present insignificant risks, and no 
    other hazardous constituents attributed to FD&C colorant production 
    were detected, the Agency is proposing not to list wastewaters from the 
    manufacture of FD&C colorants as hazardous.
        7. Dusts and dust collector fines from the manufacture of dyes and 
    pigments.
    Summary
        The Agency is proposing not to list dusts and dust collector fines 
    from the manufacture of dyes and pigments because, based on an 
    evaluation of current management and plausible management, this waste 
    does not pose a substantial potential hazard to human health and the 
    environment.
    Discussion
        Dusts and dust collector fines are generated during drying, 
    grinding, and blending operations that occur during the manufacture of 
    dyes and pigments. Dust collectors and baghouses generally are used to 
    capture and collect the dust. The total volume of this wastestream 
    reported in response to the 1991 RCRA Section 3007 Questionnaire is 143 
    metric tons. According to questionnaire data, some of the dusts and 
    fines reported by the industry are recovered and recycled back to the 
    manufacturing process or sold to shoe-polish manufacturers as a raw 
    material. Information on the percentage handled in this manner is not 
    included at the present time due to business confidentiality concerns. 
    There is a distinct economic incentive for these facilities to continue 
    reusing or selling dusts and fines in this way. This handling of dusts 
    and fines is not expected to present any significant risk to human 
    health and the environment.
        Seventeen percent of the reported waste volume is generated by a 
    facility that currently manages dusts and fines in a Subtitle C 
    landfill and the Agency believes that this facility will continue to 
    manage dusts and fines in such a manner. The dusts and fines generated 
    at this facility from organic pigments covered by this listing 
    determination are mixed with dusts and fines from inorganic pigments 
    that contain lead and chromium. The entire volume of dusts and fines, 
    comprised of the commingled organic and inorganic products dusts and 
    fines, is characteristically toxic for both lead and chromium and, 
    therefore, is a hazardous waste as defined by 40 CFR 261.24. It is 
    impractical for the facility to separate the dusts and fines covered by 
    this listing determination from these characteristic inorganic dusts 
    and fines and, thus, the facility manages the dusts and fines covered 
    by this listing determination in a Subtitle C landfill. Analysis of 
    existing plant design shows that dusts and fines are comingled in 
    ductwork that is structured such that these wastes are mixed. Without 
    significant re-design and construction, segregation of the wastes is 
    impossible. The Agency does not believe that it is plausible for the 
    facility to discontinue the practice of combining all of its dusts and 
    fines wastes and disposing of such wastes at a Subtitle C facility 
    given the physical arrangement of this facility. Management of this 
    waste in a Subtitle C landfill is not expected to pose any significant 
    level of risk to human health or the environment.
        Information on the volume and the percentage of total volume 
    disposed of in Subtitle D landfills is not included at the present time 
    due to business confidentiality concerns.
        The Agency believes the potential risks posed by the plausible 
    management practices for this volume do not warrant a hazardous waste 
    listing for dusts and fines.
        Although, due to resource constraints, the Agency was unable to 
    collect information on the characteristics of these dusts and fines, 
    the Agency estimated a worst-case risk by estimating the risk 
    associated with disposal of dusts and fines in a Subtitle D landfill 
    based on the physical/chemical properties of a mobile dye product and 
    the toxicological properties of a dye constituent known to be one of 
    the most toxic and mobile dye or pigment waste constituents. This 
    analysis demonstrated that the risk is below the initial level of 
    concern associated with disposal of this waste in a Subtitle D 
    landfill. Management of this waste in an on-site monofill was 
    determined to be not plausible because the volumes generated would not 
    justify an on-site monofill. For further information see the background 
    document on risk assessment, available in the public docket for this 
    rule.
        The Agency requests comment on the approach used to determine risk 
    posed by plausible management of the wastes and requests comment on the 
    proposed determination not to list this waste.
        9. Spent filter aids, diatomaceous earth, or adsorbents used in the 
    production of azo, anthraquinone, or triarylmethane dyes, pigments, or 
    FD&C colorants.
    Summary
        The Agency is proposing to defer a determination on whether to list 
    spent filter aids, diatomaceous earth, or adsorbents used in the 
    production of azo, anthraquinone, or triarylmethane dyes, pigments, or 
    FD&C colorants as hazardous due to insufficient waste characterization 
    data. The Agency is planning to collect additional information on this 
    wastestream. EPA then will publish a supplemental notice with a 
    proposed determination on whether to list this waste.
    
    III. Waste Minimization
    
        In the Pollution Prevention Act of 1990 (42 U.S.C. 13101 et seq., 
    Pub. L. 101-508, November 5, 1990), Congress declared pollution 
    prevention the national policy of the United States. The act declares 
    that pollution should be prevented or reduced whenever feasible; 
    pollution that cannot be prevented should be recycled or reused in an 
    environmentally safe manner wherever feasible; pollution that cannot be 
    prevented/reduced or recycled should be treated; and disposal or 
    release into the environment should be chosen only as a last resort. 
    This section first provides a general discussion of some generic 
    pollution prevention and waste minimization techniques that facilities 
    may wish to explore and second discusses and requests comment on ways 
    in which the hazardous waste listing determination program itself could 
    be structured to better promote pollution prevention and waste 
    minimization.
    
    A. Generic Approaches to Waste Minimization
    
        Waste minimization practices fall into three general groups: change 
    in production practices, housekeeping practices, and practices that 
    employ the use of equipment that by design promote waste minimization. 
    Some of these practices/equipment listed below conserve water, others 
    reduce the amount of product in the wastestream, while others may 
    prevent the creation of the waste altogether. EPA acknowledges that 
    some of these practices/equipment may lead to media transfers or 
    increased energy consumption. This information is presented for general 
    information, and is not being proposed as a regulatory requirement. 
    Production practices include:
         Triple-rinsing raw material shipping containers and 
    returning the rinsate directly to the reactor;
         Scheduling production to minimize changeover cleanouts;
         Segregating equipment by individual product or product 
    ``families;''
         Packaging products directly out of reactors;
         Steam stripping wastewaters to recovery reactants or 
    solvents for reuse;
         Using raw material drums for packaging final products; and
         Dedicating equipment for hard to clean products. 
    Housekeeping practices include:
         Performing preventive maintenance on all valves, fittings, 
    and pumps;
         Promptly correcting any leaky valves and fittings;
         Placing drip pans under valves and fittings to contain 
    leaks; and
         Cleaning up spills or leaks in bulk containment areas to 
    prevent contamination of storm or wash wasters.
    
    Equipment promoting waste minimization by reducing or eliminating waste 
    generation include:
         Low-volume/high-pressure hoses for cleaning;
         Drum triple-rinsing stations;
         Reactor scrubber systems designed to return captured 
    reactants to the next batch rather than to disposal;
         Material storage tanks with inert liners to prevent 
    contamination of water blankets with contaminants which would prohibit 
    its use in the process; and
         Enclosed automated product handling equipment to eliminate 
    manual product packaging.
        Waste minimization measures can be tailored to the needs of 
    individual industries, processes, and firms. This approach may make it 
    possible to achieve greater pollution reduction with less cost and 
    disruption to the firm.
        Defined process control and good housekeeping practices often can 
    result in significant waste volume or toxicity reduction. Evaluations 
    of existing processes also may point out the need for more complex 
    engineering approaches (e.g., waste reuse, secondary processing of 
    distillation bottoms, and use of vacuum pumps instead of steam jets) to 
    achieve waste minimization objectives. Simple physical audits of 
    current waste generation and in-plant management practices for the 
    wastes also can yield positive results. These audits often turn up 
    simple non-engineering practices that can be implemented successfully.
    
    B. Waste Minimization Approaches in the Listing Program
    
        Section 1003 of the Hazardous and Solid Waste Amendments of 1984 
    says that one of RCRA's goals is to promote protection of human health 
    and the environment and to conserve valuable material and energy 
    resources by ``minimizing the generation of hazardous waste and the 
    land disposal of hazardous waste by encouraging process substitution, 
    materials recovery, properly conducted recycling, and reuse and 
    treatment.'' Section 1003 further provides that it is a national policy 
    of the United States that, whenever feasible, the generation of 
    hazardous waste is to be reduced or eliminated as expeditiously as 
    possible. To further EPA's waste minimization goals, the Waste 
    Minimization Branch (WMB) in EPA's Office of Solid Waste (OSW) 
    established the RCRA Waste Minimization Action Plan to integrate source 
    reduction and recycling into the National RCRA Program, and RCRA 
    activities into the Agency's Pollution Prevention Strategy.
        As described in that plan, EPA's program for evaluating which 
    wastes should be listed as hazardous is an example of a regulatory 
    program that can provide opportunities for encouraging and promoting 
    real waste minimization. When a wastestream is listed as hazardous, it 
    enters the hazardous waste management system. The requirements of that 
    system can be costly and there are currently only limited ways for a 
    waste entering the system to get out. Once it is listed as a hazardous 
    waste, it remains a listed hazardous waste even after treatment and 
    safe disposal, unless delisted pursuant to 40 CFR 260.20 and 260.22. 
    Other than levels at which wastes typically are delisted, there is no 
    target for a generator to shoot for which would allow their waste to be 
    considered non-hazardous even if waste minimization actions are taken 
    that ensure the waste is not likely to pose a hazard to human health 
    and the environment. However, if a waste minimization-based exemption 
    to the listing could be provided, generators would have the regulatory 
    and economic incentive to meet the exemption. When the exemption is 
    tailored to encourage and reward waste minimization efforts, then the 
    generator could obtain the benefit of not generating a listed hazardous 
    waste while furthering national waste minimization goals.
        The Agency notes that there are several important considerations in 
    developing listing determinations that encourage waste minimization. 
    First, waste minimization-based listings must promote actual waste 
    minimization and clearly not increase risk. In addition, the listings 
    must be enforceable.
        1. Actual Waste Minimization Must Occur. The Agency is interested 
    in taking comment on developing listings that encourage reductions in 
    volumes, reductions in concentrations of constituents of concern 
    (without diluting constituents in an effort to reduce concentration), 
    reductions in environmental loading of constituents of concern, and/or 
    the removal of constituents of concern (or process derivatives of 
    concern) from the manufacturing process, and/or the beneficial reuse, 
    recycling, or reclamation of the wastestreams themselves, provided 
    human health and the environment is protected. A waste minimization-
    based listing, for example, must be crafted so as not to result simply 
    in cross-media transfer, and so as not to leave uncontrolled wastes 
    reduced in volume or concentration, but still posing a significant 
    hazard. The Agency believes that generators must make a commitment that 
    waste minimization in fact would occur, and that a real investment in 
    waste minimization techniques, equipment, and process changes would be 
    carried out.
        2. No Increase in Risk Can Occur. A waste minimization-based 
    listing (or variable level) must protect human health and the 
    environment and not increase risk. A hazardous waste listing achieves 
    the goal of minimizing risk by placing a wastestream in the hazardous 
    waste management system. Any exemption which takes a wastestream out of 
    this system must be shown to provide an equivalent decrease in risk as 
    that provided by the listing itself. It would be unacceptable, for 
    example, for waste minimization actions simply to result in cross-media 
    transfer of wastes. Chemical substitution that fails to reduce the 
    risks posed by a wastestream is another example of a practice that 
    would not be considered to be waste minimization. Another specific 
    concern involves the possible presence of other constituents in a 
    wastestream for which the waste was not specifically listed but which 
    also may pose risk to human health or the environment. A waste 
    minimization-based listing must consider the impact of letting the 
    entire wastestream out of the hazardous waste management system.
        3. Enforceability. The Agency is particularly concerned about the 
    enforceability of waste minimization-based variance to a listing. In 
    particular, the Agency has concerns about the following factors:
         The amount of testing or monitoring required,
         Ease by which a State inspector could check compliance,
         How a generator would demonstrate compliance with the 
    waste minimization-based exemption,
         The likelihood that a State agency would adopt a waste 
    minimization approach in its listing regulations, and
         The ability of a State agency to oversee an exemption.
    
    Any waste minimization-based listing must account for these concerns. 
    (Many of these issues now are being considered in EPA's deliberations 
    on the Hazardous Waste Identification Rule.)
    
    C. Specific Approaches to Waste Minimization
    
        The Agency can and has used different regulatory mechanisms to 
    promote waste minimization in the listing program. The discussion below 
    will describe several options the Agency has identified as an approach 
    to tailoring listings that encourages generators to use waste 
    minimization practices. This approach could apply to any listing 
    determination. Also included in this discussion are specific references 
    to today's proposed listing determination for dyes and pigments.
    Quantity-Based Listings
        A potential method of structuring a waste listing to promote waste 
    minimization would be to establish a quantity-based exemption for the 
    wastes listed. Under such an approach, the listing of a specific 
    wastestream would be accompanied by a quantity-based exemption for the 
    specific wastestream involved. Quantity can refer to either a 
    concentration of constituents in a waste (measured or calculated) or 
    the mass of constituents released to the environment. The Agency 
    believes that this approach would encourage waste minimization because 
    a facility would have to meet a risk-based quantitation target for a 
    wastestream in order to qualify for the exemption, thereby requiring 
    reductions in the mass or concentration (or both) of the constituents 
    of concern. In reducing mass loading or concentration (or both) of the 
    wastes, the Agency's waste minimization goals are achieved.
        A concentration basis is easier to measure and track than a limit 
    based on loading or mass. Setting a limit based on loadings or mass 
    addresses total loadings to the environment and recognizes waste 
    minimization efforts that result in reductions in both mass of 
    pollutant and volume of total wastestream. However, a mass loading 
    approach poses significantly more burden in terms of monitoring and 
    compliance and may not take into account concentrations of constituents 
    in a waste. The Agency requests comment on the use of production or 
    mass-based limits, and on possible monitoring approaches.
        A variation on this approach is an adaptation of the ``headworks 
    rule'' (40 CFR 261.3(a)(2)(iv)(A)-(E)) to a listing. The original rule, 
    promulgated on November 17, 1981 (46 FR 56582) allows for calculated 
    amounts of certain spent solvents, commercial chemical products, 
    petroleum refining wastes, and laboratory residuals to be sent to a 
    facility's wastewater treatment plant, and for the wastewaters and 
    sludges (beyond the headworks) to be exempted from the mixture rule. 
    The Agency also proposed in the March 1, 1994 carbamates listing 
    proposal (59 FR 9808-9864) to provide a similar exemption to a 
    wastewater proposed for listing in the same notice.
        Under the ``headworks'' exemption approach (e.g., 40 CFR 
    261.3(a)(2)(iv)(H)), the wastewaters and treatment sludges would be 
    exempt from the listing as long as the industry could show that the 
    total quantity of hazardous constituents that pose risk in a 
    wastestream, divided by the undiluted wastewater flow for wastewaters 
    on an average weekly basis from the particular product process subject 
    to the listing was less than a calculated quantity. The calculated 
    quantity would be based on a risk assessment.
        The Agency would have to be able to determine the relationship 
    between the amount of raw material used and the presence of particular 
    constituents in the wastestream. The Agency requests comment on whether 
    determining such a relationship is feasible for the dye and pigment 
    industries. To qualify for such an exemption, the facility would have 
    to use existing inventory records of raw materials that go into the 
    process. The facility can subtract the quantity of materials that, in 
    fact, do not go into the wastewater treatment system, either by 
    chemical reaction or material recovery techniques (i.e., distillation, 
    reuse, reverse osmosis, etc.). The facility may not subtract any 
    quantity assumed to volatilize. The quantity of material left then 
    would be converted to resulting levels of constituents expected to be 
    generated based on quantity of raw material used. The levels of 
    constituents then would be divided by the average weekly flow of the 
    wastewaters into the headworks of the wastewater treatment system at 
    the time the process is being run to determine total concentrations of 
    constituents in wastewater. If the total concentration of constituents 
    of concern is less than the amount calculated based on the risk 
    assessment, the wastewaters and treatment sludges would qualify for the 
    exemption. This approach has the advantage of determining 
    concentrations in a mathematical, rather than an analytical way. The 
    disadvantage is that it requires collection of process flow data and 
    specific plant chemistry information.
        The Agency realizes that constituent loading into the wastewater 
    treatment system may have to be reduced significantly (up to two to 
    three orders of magnitude in many cases) in order to qualify for an 
    exemption of this sort. Therefore, the Agency solicits comment on 
    whether such levels are achievable, and what other calculation methods 
    may exist (such as one based on production mass).
        Such an exemption would apply only after the wastewaters have 
    arrived at the headworks of a facility's wastewater treatment system. 
    The Agency would not allow it to apply to wastewaters before they reach 
    the headworks. Generators who wish to qualify for such an exemption 
    would be required to use flow statistics for the period in which the 
    processes generating the wastewaters are being run. Finally, such an 
    exemption would apply only to wastewater flow for that wastestream, not 
    to flow figures from unrelated processes that serve only to dilute the 
    wastewaters.
        In addition, generators would be required to keep records of 
    average weekly flow in the production processes, especially when the 
    processes generating the listed wastewaters are run. When land disposal 
    restrictions are applied to a waste subject to such an exemption, 
    generators would need to comply with 40 CFR 268.7(a)(6), which states 
    that the generator who has produced a waste subject to an exemption in 
    40 CFR 261.2-261.6 must keep a notification in the facility's file 
    stating that such a waste has been generated, the fact that it is 
    restricted, and the disposition of the waste.
        The Agency seeks comment on the recordkeeping burden that 
    accompanies its implementation. The Agency realizes that facilities 
    that would wish to take advantage of such an exemption would be 
    required to allow compliance personnel to examine process records 
    (reaction rates, reactants, process flows, etc.) to verify that a 
    facility is able to achieve the exemption. Therefore, the Agency 
    solicits comments on this topic as well.
        A quantity-based exemption in a listing determination bears a 
    strong relationship to another ongoing Agency project which seeks to 
    establish an exit from the hazardous waste management program. The 
    Hazardous Waste Identification Rule (HWIR) project is an effort, in 
    part, to set exit criteria for any listed hazardous waste so that 
    materials which clearly fail to pose a threat to human health and the 
    environment can exit the Subtitle C system. The HWIR concept, as 
    currently envisioned, would be expected to be similar to that of a 
    quantity-based exemption for a specific listed hazardous waste: a risk- 
    based exemption process that employs analysis of multiple exposure 
    pathways to determine a safe exit or exemption level. A principal 
    difference between the HWIR concept under discussion and a quantity-
    based listing could be that HWIR is meant to apply to all listed 
    wastestreams, while a quantity-based listing could be targeted to a 
    specific wastestream in a listing determination. In that sense, a 
    listing exemption could be considered to be more tailored to the known 
    exposure routes of a specific wastestream and may be able to generate 
    an exemption level which is specific to that wastestream. For example, 
    if the listing determination analysis shows a wastestream in a listing 
    can be managed only in tanks, then the exemption analysis could be 
    focused on the exposure pathways affected only by tanks. The exemption 
    levels for that wastestream could be tailored to those exposure routes 
    (air pathways) and could be different than HWIR exit criteria. The 
    Agency solicits comment on the advantages and disadvantages of a 
    quantity-based exemption in listing determinations to a more generic 
    exit level lkie that being contemplated in the HWIR project 
    discussions.
    Relationship to the Definition of Solid Waste
        The Agency has observed in the dye and pigment and other industries 
    that material recovery may be discouraged due to restrictions placed on 
    materials designated as ``solid and then hazardous'' waste, as defined 
    by RCRA. Over the past two years, the Agency's Definition of Solid 
    Waste Task Force in the Office of Solid Waste examined possible 
    modifications to the definition of solid waste to encourage 
    environmentally sound recycling. A final report of the Task Force was 
    issued on September 19, 1994.
        An example in the dye and pigment industries of using as a product 
    a material that ordinarily would be a waste involves the blending and 
    sale of collected dusts and fines as inexpensive black pigments useful 
    to shoe polish manufacturers.
    
    D. Waste Minimization and the Dye and Pigment Industries
    
        The dye and pigment industries have expended considerable effort to 
    cooperate with the Agency on a voluntary waste minimization program, 
    coordinated through ETAD. As part of this effort, waste minimization, 
    recycle, and reuse practices in the dye and pigment industries were 
    described for all aspects of production in the ``Pollution Prevention 
    Guidance Manual for the Dye Manufacturing Industry'' (EPA/741/B-92-
    001).
        The Agency is interested in options to modify today's proposed 
    listing determinations to support and enhance the voluntary waste 
    minimization efforts already initiated by the dye and pigment 
    industries. The Agency requests comment on the feasibility of the waste 
    minimization-based listing approaches described above for the dye and 
    pigment industries. EPA also solicits ideas and comments on other 
    possible approaches to tailor the hazardous waste listings and promote 
    waste minimization in the dye and pigment industries. In particular, 
    the Agency requests comment on other approaches that may provide more 
    flexibility for waste minimization and better assure that constituent 
    reductions would be achieved through waste minimization (rather than 
    through treatment).
        EPA specifically requests comment on the feasibility of developing 
    the quantity-based listing approach described above for the dye and 
    pigment industries. The quantity-based approach is based on the 
    Agency's experience with other industries in which production is 
    continuous. Because of the batch nature of production and the 
    multiplicity of chemicals involved in the dye and pigment industries, 
    the quantity-based listing approach may be more difficult for this 
    industry. The Agency requests comment on how these issues (i.e., batch 
    processes, multiple chemicals) might be addressed in a quantity-based 
    listing approach or other waste minimization-based option.
        The Agency also solicits comment on whether certain of the dye and 
    pigment wastestreams are better candidates for waste minimization, and 
    whether a waste minimization-based listing approach should target these 
    wastes. Finally, EPA requests comment on the testing and monitoring 
    needed to ensure proper implementation of a waste minimization listing 
    approach. Based on the comments the Agency receives on the above 
    issues, EPA may issue a supplemental proposal addressing a waste 
    minimization-based listing approach for the dyes and pigments industry.
    
    IV. Applicability of the Land Disposal Restrictions Determinations
    
    A. Request for Comment on the Agency's Approach to the Development of 
    BDAT Treatment Standards
    
        RCRA requires EPA to make a land disposal prohibition determination 
    for any hazardous waste that is newly identified or listed in 40 CFR 
    part 261 after November 8, 1984, within six months of the date of 
    identification or final listing (RCRA Section 3004(g)(4), 42 U.S.C. 
    6924(g)(4)). EPA also is required to set ``* * * levels or methods of 
    treatment, if any, which substantially diminish the toxicity of the 
    waste or substantially reduce the likelihood of migration of hazardous 
    constituents from the waste so that short-term and long-term threats to 
    human health and the environment are minimized'' (RCRA Section 
    3004(m)(1), 42 U.S.C. 6924(m)(1)). Land disposal of wastes that meet 
    treatment standards thus established by EPA is not prohibited. The 
    wastes being proposed for listing in this action would be subject to 
    this requirement once a final rule is promulgated.
        A general overview of the Agency's approach in performing analysis 
    of how to develop treatment standards for hazardous wastes can be found 
    in greater detail in Section III.A.1 of the preamble to the final rule 
    that set land disposal restrictions (LDR's) for the Third Third wastes 
    (55 FR 22535, June 1, 1990). The framework for the development of the 
    entire Land Disposal Restrictions program was promulgated November 7, 
    1986. (51 FR 40572).
        While the Agency prefers source reduction/pollution prevention and 
    recycling/recovery over conventional treatment, inevitably, some wastes 
    (such as residues from recycling and inadvertent spill residues) will 
    be generated. Thus, standards based on treatment using ``best 
    demonstrated available technology'' (BDAT) will be required to be 
    developed for these wastes if a final rule listing them as hazardous is 
    promulgated.
        Treatment standards typically are established based on the 
    performance data from the treatment of the listed waste or wastes with 
    similar chemical and physical characteristics or similar concentrations 
    of hazardous constituents. Treatment standards are established for both 
    wastewater and nonwastewater forms on a constituent-specific basis. The 
    constituents selected for regulation under the Land Disposal 
    Restrictions Program are not necessarily limited to those identified as 
    present in the listings proposed in this action, but include those 
    constituents or parameters that will ensure that the technologies are 
    operated properly.
        Although data on waste characteristics and current management 
    practices for wastes proposed in this action have been gathered as part 
    of the administrative record for this rule, the Agency has not 
    completed its evaluation of the usefulness of these data for developing 
    specific treatment standards or assessing the capacity to treat (or 
    recycle) these wastes.
        Some treatment technologies previously promulgated for newly 
    identified hazardous organic wastes are: chemical oxidation, wet air 
    oxidation, activated sludge, steam stripping, activated carbon, solvent 
    extraction, pyrolysis, thermal desorption, UV photolysis, ozonation, 
    and incineration. A current description of these technologies and what 
    types of wastes they are used to treat is available as a background 
    document and can be obtained by contacting NTIS (National Technical 
    Information Service, 5285 Port Royal Road, Springfield, VA 22161, 
    (703)487-4650) and requesting document PB91-160556, ``Treatment 
    Technology Document,'' L. Rosengrant, dated January, 1991, USEPA-OSW.
        EPA intends to propose treatment standards for K162 through K166 in 
    a separate rulemaking. However, EPA specifically is soliciting comment 
    and data on the following as they pertain to the proposed listing of 
    dye and pigment industries wastes K162 through K166 as described in 
    this action:
        (1) Technical descriptions of treatment systems that are or could 
    be used potentially for these wastes;
        (2) Descriptions of alternative technologies that currently might 
    be available or anticipated as applicable;
        (3) Performance data for the treatment of these or similar wastes 
    (in particular, constituent concentrations in both treated and 
    untreated wastes, as well as equipment design and operating 
    conditions);
        (4) Information on known or perceived difficulties in analyzing 
    treatment residues or specific constituents;
        (5) Quality assurance/quality control information for all data 
    submissions;
        (6) Factors affecting on-site and off-site treatment capacity;
        (7) Information on the potential costs for set-up and operation of 
    any current and alternative treatment technologies for these wastes;
        (8) Information on waste minimization approaches.
    
    B. Request for Comment on the Agency's Approach to the Capacity 
    Analyses in the LDR Program
    
        In the land disposal restrictions determinations, the Agency must 
    demonstrate that adequate treatment or recovery capacity exists to 
    manage a newly listed waste with BDAT standards before it can restrict 
    the waste from further land disposal. The Agency performs capacity 
    analyses to determine if sufficient alternative treatment or recovery 
    capacity exists to accommodate the volumes of waste that will be 
    affected by the land disposal prohibition. If adequate capacity exists, 
    the waste must be treated to meet the BDAT standard before land 
    disposal. If adequate capacity does not exist, RCRA Section 3004(h) 
    authorizes EPA to grant a national capacity variance from the effective 
    date of the treatment standard for the waste for up to two years or 
    until adequate alternative treatment capacity becomes available, 
    whichever is sooner.
        To perform capacity analyses, the Agency needs to determine the 
    volume of the listed waste that will require treatment prior to land 
    disposal. The volume of waste requiring treatment depends, in turn, on 
    the waste management practices employed by the listed waste generators. 
    Data on waste management practices for these wastes were collected 
    during the development of this proposed rule. However, as the 
    regulatory process proceeds, generators may decide to minimize or 
    recycle their wastes or otherwise alter their management practices. 
    Thus, EPA will update and monitor changes in management practices 
    because these changes will affect the final volume of waste requiring 
    commercial treatment capacity. Therefore, EPA needs information on 
    current and future waste management practices for these wastes, 
    including the volume of waste that are recycled, mixed with or co-
    managed with other waste and discharged under Clean Water Act 
    provisions; and the volume and types of residuals that are generated by 
    various management practices applicable to newly listed and identified 
    wastes (e.g., treatment residuals).
        The availability of commercial treatment capacity for these wastes 
    determines whether or not a waste is granted a capacity variance under 
    RCRA Section 3004(h). EPA continues to update and monitor changes in 
    available commercial treatment capacity because the commercial 
    hazardous waste management industry is extremely dynamic. For example, 
    national commercial treatment capacity changes as new facilities come 
    on-line, as new units and new technologies are added at existing 
    facilities, and as facilities expand existing units. The available 
    capacity at commercial facilities also changes as facilities change 
    their commercial status (e.g., changing from a fully commercial to a 
    limited commercial or captive facility). To determine the availability 
    of capacity for treating these wastes, the Agency needs to consider 
    currently available data, as well as the timing of any future changes 
    in available capacity.
        For previous land disposal restriction rules, the Agency performed 
    capacity analyses using data from national surveys, including the 1987 
    National Survey of Hazardous Waste Treatment, Storage, Disposal, and 
    Recycling Facilities (the TSDR Survey) and the 1987 National Survey of 
    Hazardous Waste Generators (the Generator Survey). However, these 
    surveys cannot be used to determine the volumes of dye and pigment 
    wastes requiring treatment since these wastes were not included in the 
    surveys. Additionally, these surveys may not contain adequate 
    information on currently available capacity to treat newly identified 
    wastes because the data reflect 1986 capacity and do not include 
    facility expansions or closures that have occurred since then. Although 
    adjustments have been made to commercially available capacity to 
    account for changes in waste management through 1992, this was not done 
    on a consistent basis across all waste management practices.
        EPA gathered data on waste generation, characteristics and 
    management practices for the listing determination of dye and pigment 
    wastes in the RCRA Section 3007 Questionnaire of 1991. The Agency has 
    compiled the capacity-related information from the survey responses and 
    is soliciting any updated or additional pertinent information.
        To perform the necessary capacity analyses in the land disposal 
    restrictions rulemaking, the Agency needs reliable data on current 
    waste generation, waste management practices, available alternative 
    treatment capacity, and planned treatment capacity. The Agency will 
    need the annual generation volumes of waste by each waste code 
    including wastewater and nonwastewater forms, and soil or debris 
    contaminated with these wastes and the quantities stored, treated, 
    recycled, or disposed due to any change of management practices. EPA 
    also requests data from facilities capable of treating these wastes on 
    their current treatment capacity and any plans they may have in the 
    future to expand or reduce existing capacity. Specifically, the Agency 
    requests information on the determining factors involved in making 
    decisions to build new treatment capacity. Waste characteristics such 
    as pH level, BTUs, anionic character, total organic carbon content, 
    constituents concentration, and physical form also may limit the 
    availability of certain treatment technologies. For these reasons, the 
    Agency requests data and comments on waste characteristics that might 
    limit or preclude the use of any treatment technologies.
    
    V. Compliance Dates
    
    A. Notification
    
        Under RCRA Section 3010, any person generating, transporting, or 
    managing a hazardous waste must notify EPA (or an authorized State) of 
    its activities. Section 3010(a) allows EPA to waive, under certain 
    circumstances, the notification requirement under Section 3010 of RCRA. 
    If these hazardous waste listings are promulgated, EPA is proposing to 
    waive the notification requirement as unnecessary for persons already 
    identified within the hazardous waste management universe (i.e., 
    persons who have an EPA identification number under 40 CFR 262.12). EPA 
    is not proposing to waive the notification requirement for waste 
    handlers who have neither notified the Agency that they may manage 
    hazardous wastes nor received an EPA identification number. Such 
    individuals will have to provide notification under RCRA Section 3010.
    
    B. Interim Status and Permitted Facilities
    
        Because HSWA requirements are applicable in authorized States at 
    the same time as in unauthorized States, EPA will regulate EPA 
    Hazardous Wastes Nos. K162 through K166 until States are authorized to 
    regulate these wastes. Thus, once this regulation becomes effective as 
    a final rule, EPA will apply Federal regulations to these wastes and to 
    their management in both authorized and unauthorized States.
    
    VI. State Authority
    
    A. Applicability of Rule in Authorized States
    
        Under Section 3006 of RCRA, EPA may authorize qualified States to 
    administer and enforce the RCRA program within the State. (See 40 CFR 
    part 271 for the standards and requirements for authorization.) 
    Following authorization, EPA retains enforcement authority under 
    Sections 3007, 3008, 3013, and 7003 of RCRA, although authorized States 
    have primary enforcement responsibility.
        Before the Hazardous and Solid Waste Amendments of 1984 (HSWA) 
    amended RCRA, a State with final authorization administered its 
    hazardous waste program entirely in lieu of the Federal program in that 
    State. The Federal requirements no longer applied in the authorized 
    State, and EPA could not issue permits for any facilities located in 
    the State with permitting authorization. When new, more stringent 
    Federal requirements were promulgated or enacted, the State was 
    obligated to enact equivalent authority within specified time-frames. 
    New Federal requirements did not take effect in an authorized State 
    until the State adopted the requirements as State law.
        By contrast, under Section 3006(g) of RCRA, 42 U.S.C. 6926(g), new 
    requirements and prohibitions imposed by the HSWA (including the 
    hazardous waste listings proposed in this notice) take effect in 
    authorized States at the same time that they take effect in non-
    authorized States. EPA is directed to implement those requirements and 
    prohibitions in authorized States, including the issuance of permits, 
    until the State is granted authorization to do so. While States still 
    must adopt HSWA-related provisions as State law to retain final 
    authorization, the Federal HSWA requirements apply in authorized States 
    in the interim.
    
    B. Effect on State Authorizations
    
        Because this proposal (with the exception of the actions proposed 
    under CERCLA authority) will be promulgated pursuant to the HSWA, a 
    State submitting a program modification is able to apply to receive 
    either interim or final authorization under Section 3006(g)(2) or 
    3006(b), respectively, on the basis of requirements that are 
    substantially equivalent or equivalent to EPA's requirements. The 
    procedures and schedule for State program modifications under Section 
    3006(b) are described in 40 CFR 271.21. It should be noted that all 
    HSWA interim authorizations currently are scheduled to expire on 
    January 1, 2003 (see 57 FR 60129, February 18, 1992).
        Section 271.21(e)(2) of EPA's state authorization regulations (40 
    CFR part 271) requires that States with final authorization modify 
    their programs to reflect Federal program changes and submit the 
    modifications to EPA for approval. The deadline by which the States 
    must modify their programs to adopt this proposed regulation, if it is 
    adopted as a final rule, will be determined by the date of promulgation 
    of a final rule in accordance with 40 CFR 271.21(e)(2). If the proposal 
    is adopted as a final rule, Table 1 at 40 CFR 271.1 will be amended 
    accordingly. Once EPA approves the modification, the State requirements 
    become RCRA Subtitle C requirements.
        States with authorized RCRA programs already may have regulations 
    similar to those in this proposed rule. These State regulations have 
    not been assessed against the Federal regulations being proposed to 
    determine whether they meet the tests for authorization. Thus, a State 
    would not be authorized to implement these regulations as RCRA 
    requirements until State program modifications are submitted to EPA and 
    approved, pursuant to 40 CFR 271.21. Of course, States with existing 
    regulations that are more stringent than or broader in scope than 
    current Federal regulations may continue to administer and enforce 
    their regulations as a matter of State law.
        It should be noted that authorized States are required to modify 
    their programs only when EPA promulgates Federal standards that are 
    more stringent or broader in scope than existing Federal standards. 
    Section 3009 of RCRA allows States to impose standards more stringent 
    than those in the Federal program. For those Federal program changes 
    that are less stringent or reduce the scope of the Federal program, 
    States are not required to modify their programs. See 40 CFR 271.21(e). 
    This proposed rule, if promulgated, would expand the scope of the 
    Federal program by adding additional listed wastes. Therefore, States 
    would be required to modify their programs to retain authorization to 
    implement and enforce these regulations.
    
    VII. CERCLA Designation and Reportable Quantities
    
        All hazardous wastes listed under RCRA and codified in 40 CFR 
    261.31 through 261.33, as well as any solid waste that exhibits one or 
    more of the characteristics of a RCRA hazardous waste (as defined in 
    Sections 261.21 through 261.24), are hazardous substances under the 
    Comprehensive Environmental Response, Compensation, and Liability Act 
    of 1980 (CERCLA), as amended. See CERCLA Section 101(14)(C). CERCLA 
    hazardous substances are listed in Table 302.4 at 40 CFR 302.4 along 
    with their reportable quantities (RQs). RQs are the minimum quantity of 
    a hazardous substance that, if released, must be reported to the 
    National Response Center (NRC) pursuant to CERCLA Section 103. In this 
    action, the Agency is proposing to list the proposed wastes in this 
    action as CERCLA hazardous substances in Table 302.4 of 40 CFR 302.4, 
    but is taking no action to adjust the one-pound statutory RQs for these 
    substances.
        Reporting Requirements. Under Section 102(b) of CERCLA, all 
    hazardous substances newly designated under CERCLA will have a 
    statutory RQ of one pound unless and until adjusted by regulation. 
    Under CERCLA Section 103(a), the person in charge of a vessel or 
    facility from which a hazardous substance has been released in a 
    quantity that is equal to or exceeds its RQ immediately shall notify 
    the NRC of the release as soon as that person has knowledge thereof. 
    The toll-free number of the NRC is 1-800-424-8802; in the Washington, 
    DC metropolitan area, the number is (202) 426-2675. In addition to this 
    reporting requirement under CERCLA, Section 304 of the Emergency 
    Planning and Community Right-to-Know Act of 1986 (EPCRA) requires 
    owners or operators of certain facilities to report the release of a 
    CERCLA hazardous substance to State and local authorities. Immediately 
    after the release of a RQ or more, EPCRA Section 304 notification must 
    be given to the community emergency coordinator of the local emergency 
    planning committee for each area likely to be affected by the release, 
    and to the State emergency response commission of any State likely to 
    be affected by the release.
        If this proposal is promulgated as a final rule, releases equal to 
    or greater than the one-pound statutory RQ will be subject to the 
    requirements described above, unless and until the Agency adjusts the 
    RQs for these substances in a future rulemaking.
    
    VIII. Economic Impact Analysis
    
        This section of the preamble summarizes the costs and benefits of 
    the dye and pigment hazardous waste listings. Based upon the EIA, the 
    Agency estimates that the listing of the five dye and pigment 
    production wastes discussed above may result in nationwide, pre-tax, 
    annualized costs of approximately $18.1 million for compliance in 
    commercial Subtitle C landfills. The possible future costs of this 
    listing including compliance with land disposal restrictions (LDRs) 
    range from $20.3 to $70.7 million per year. The $70.7 million 
    represents off-site incineration of non-wastewaters, while the $20.3 
    million assumes facilities with large non-wastewater waste volumes will 
    construct on-site incinerators. A complete discussion of the EIA is 
    available in the regulatory docket entitled ``Costs and Economic Impact 
    Analysis of Listing Hazardous Wastes from the Organic Dye and Pigment 
    Industries,'' November 28, 1994.
    
    A. Compliance Costs for Listings
    
        The remainder of this section briefly describes (1) the universe of 
    dye and pigment production facilities and volumes of the seven dye and 
    pigment production wastes proposed to be listed, (2) the methodology 
    for determining incremental cost and economic impacts to regulated 
    entities, (3) the potential remedial action costs, and (4) economic 
    impacts. Results of the analysis are summarized in Table VIII-1.
    1. Universe of Dye and Pigment Production Facilities and Waste Volumes
        In order to estimate costs for the EIA, it first was necessary to 
    estimate the total annual generation of dye and pigment production 
    wastes affected by this action. As described in Section II.B of this 
    preamble, the portion of the dye and pigment industry producing 
    products affected by this listing is composed of 33 manufacturers 
    operating 49 facilities producing dyes and pigments. In 1992, U.S. 
    sales of all organic dyes and pigments totalled 403 million lbs., with 
    a value of $1,691 million. Total annual product volumes and waste 
    quantities generated by these affected facilities were derived from a 
    1991 survey of the dye and pigment production industries. The 
    production volume and, hence, waste volume for dyes and pigments varies 
    year to year depending on which colors are popular. A season in which 
    dark colors are in fashion will produce higher volumes of waste; it is 
    not known which colors were predominant in the study year.
    2. Method for Determining Cost and Economic Impacts
        This section details EPA's approach for estimating the incremental 
    compliance cost and the economic impacts attributable to the listing of 
    dye and pigment production wastes. Because the dye and pigment 
    production industries are moderately small (33 manufacturers currently 
    operating 49 facilities), EPA was able to collect facility-specific 
    information and estimate incremental costs at the wastestream level. 
    For ten of the 49 facilities, however, some of the waste generation 
    data were missing. In these cases, waste generation amounts were 
    estimated. The information used in this analysis was collected in 1992 
    through RCRA Section 3007 Questionnaires, engineering site visits, and 
    sampling and analysis of wastestreams.
    
    Approach to the Cost Analysis
    
        EPA's approach to the cost analysis for this rule was to compare 
    the cost of current management practices, as reported in the RCRA 
    Section 3007 Questionnaire by dye and pigment production facilities, 
    with the projected cost of management to comply with the RCRA Subtitle 
    C hazardous waste program. An additional analysis included the future 
    cost to the industry of complying with land disposal restrictions. This 
    difference in cost, when annualized,\9\ represents the incremental 
    annual compliance costs attributable to the rule.
    ---------------------------------------------------------------------------
    
        \9\Costs are discounted at a pre-tax rate of 4 percent over a 
    20-year period.
    ---------------------------------------------------------------------------
    
    Baseline or Current Management Scenario
    
        Relying on survey responses and engineering site visits, EPA was 
    able to determine the current (i.e., 1991) management practices for the 
    handling and disposal of dye and pigment production wastes. Current 
    management practices varied among facilities and wastestreams, and 
    included such practices as on-site monofilling, off-site incineration, 
    on-site destruction in boilers, and off-site landfilling in municipal, 
    industrial or Subtitle C landfills. These current management practices 
    at each facility represent the baseline scenario of the analysis.
        As part of the survey, EPA asked each facility to identify current 
    costs for the management of dye and pigment production wastes. For this 
    analysis, EPA relied on the industry's own waste-specific estimates 
    concerning the cost of current management. EPA realizes that future 
    events, such as waste minimization efforts, may change waste generation 
    volumes and, thus, future waste management costs.
    
    Post-Regulatory Management Scenarios
    
        In estimating the cost of compliance with the listing of dye and 
    pigment production wastes as RCRA hazardous wastes, EPA assessed the 
    potential waste management on the part of industry to the listing and 
    also assessed the management cost in response to LDRs.
        Initial waste management, excluding land disposal restrictions, 
    assumes all non-wastewaters will be sent to off-site Subtitle C 
    landfills. Wastewaters are assumed to be handled in tanks, at an 
    estimated cost of $18.1 million/yr. It is important to note that 81 to 
    95 percent of the total, annual, incremental compliance costs result 
    from listing the non-wastewaters. The non-wastewaters comprise less 
    than one percent of the quantity of the affected wastes.
        There were two possible management strategies examined for the dye 
    and pigment industries following the promulgation of LDRs. The first 
    strategy, the higher-cost response, is waste management, including land 
    disposal restrictions, with all non-wastewaters being sent to off-site 
    incinerators. Wastewaters are assumed to be handled in newly-
    constructed treatment impoundments, which makes this strategy an upper-
    bound estimate ($70.7 million/yr) because the other option for 
    wastewaters, handling in tanks, is marginally less expensive.
        The second strategy for waste management assumes facilities with 
    high waste volumes will construct on-site incinerators in which to 
    treat their non-wastewaters, with the remaining facilities sending 
    their wastes to off-site incinerators ($20.3 million/yr). Wastewaters 
    are assumed to be handled in newly constructed treatment impoundments.
    3. Potential Remedial Action Costs
        In addition to dye and pigment production wastes, this listing can 
    affect the management of soils, ground water, and other remedial 
    materials. The Agency's ``contained in'' policy defines certain 
    remediation wastes ``containing'' a listed hazardous waste as a RCRA 
    hazardous waste. It is possible that areas of past dye and pigment 
    waste management, spills, or disposal, which met the proposed listing 
    description at the time they were placed on the land, still may have 
    contaminant concentrations which exceed ``contained in'' levels. A 
    person who disturbs such material can become a generator of RCRA 
    hazardous waste. The likelihood of this imposing an additional burden 
    is moderate because at least 9 of the 49 dye and pigment production 
    facilities already are permitted TSDFs. Releases from all solid waste 
    management units at these TSDFs, including those that in the future may 
    be found to contain a waste meeting the dye and pigment listing 
    descriptions, already are covered by facility-wide clean-up rules under 
    40 CFR 264.101. This issue will be more likely to arise from historical 
    off-site management at facilities that were not TSDFs. The pre-tax, 
    incremental cost of corrective action liabilities has been estimated at 
    less than $8.8 million.
    
      Table VIII-1.--Total, Incremental, Pre-tax, Annualized Social Costs for the Dye and Pigment Industry for the  
     Listing Action, and Land Disposal Restrictions Including Off-Site Incineration and On-Site Incineration by Each
                                               Post-Regulatory Waste Code                                           
    ----------------------------------------------------------------------------------------------------------------
                                                                   Total annualized costs    Total annualized costs 
                                         Total annualized costs       for LDR off-site           for LDR on-site    
                Waste code                 for listing\10\ ($        incineration\11\ ($       incineration\12\ ($  
                                               millions)                  millions)                 millions)       
    ----------------------------------------------------------------------------------------------------------------
    K162.............................                   2.77                      24.76                      5.83   
    K163.............................                   2.64                       2.66                      2.64   
    K164.............................                   8.50                      38.98                      7.38   
    K165.............................                   0.62                       0.70                      0.62   
    K166.............................                   3.50                       3.53                      3.53   
    RCRA.............................                   0.03                       0.06                      0.31   
          Total\13\..................                  18.05                      70.69                    20.31    
    ----------------------------------------------------------------------------------------------------------------
    \10\The listing estimate assumes non-wastewaters will be managed in Subtitle C landfill and wastewaters will be 
      handled in tanks.                                                                                             
    \11\This upper-bound estimate assumes non-wastewaters are incinerated off-site and wastewaters are handled in   
      newly constructed treatment impoundments.                                                                     
    \12\This lower-bound estimate which includes LDRs assumes the construction of on-site incincerators for         
      facilities with non-wastewater volumes over 635 MT/yr. Wastewaters are handled in newly constructed treatment 
      impoundments.                                                                                                 
    \13\Numbers may not add due to rounding.                                                                        
    
    4. Economic Impacts
        The following economic impacts potentially are overestimated as a 
    result of inconsistencies in the reporting in the RCRA Section 3007 
    Questionnaire responses. Some facilities were found to have reported 
    production quantities on a pure product basis while reporting the 
    average selling price per pound on a dilute product basis. This results 
    in an underestimation of revenues, as a result of reduced production 
    volumes, and an overestimation of economic impacts. In addition, some 
    of the volume of several of the wastestreams is for co-managed wastes. 
    The values of production for the co-generated products were not 
    available and, thus, further underestimated revenues which resulted in 
    overestimated economic impacts. Economic impacts were evaluated based 
    on incremental, annualized compliance costs discounted at an after-tax 
    rate of 7 percent over a 20-year period. Of the 49 facilities 9 
    facilities may incur potential ``significant economic impacts'' (i.e., 
    bear compliance costs that would require product cost increases of at 
    least 5 percent) with one of these facilities facing product-line 
    discontinuation. Sixteen of the 49 facilities are estimated to incur 
    potential significant impacts assuming possible future costs for the 
    high-cost LDR alternative. Economic ratios indicate potential closure 
    or product-line discontinuation for 4 of the 16 significantly affected 
    facilities. Under the low-cost LDR alternative, 15 of the 49 facilities 
    are estimated to incur potential significant economic impacts. Two of 
    the 15 significantly affected facilities are estimated to incur closure 
    or product-line discontinuation.
    5. Benefits of Listings
        One objective of a population analysis is to estimate the number of 
    cancer cases that could be avoided as a result of the implementation of 
    the proposed rule. People drinking contaminated water from residential 
    wells located near the source of contamination, people eating home-
    grown vegetables contaminated by blowing dust or vapors, and people 
    breathing air contaminated by a disposal unit are the potentially 
    exposed population for this rule. The Agency did not estimate the 
    population risks from current practices or the incremental risk 
    reduction from future actions as a result of the proposed regulation; 
    however, preliminary analysis suggests that the incremental risk in 
    terms of cancer cases avoided is expected to be near zero.
        One benefit associated with this rulemaking is to place 
    wastestreams the Agency has determined could pose a risk to human 
    health and the environment into the hazardous waste management system. 
    When wastestreams are placed in this system, the risk associated with 
    their disposal is minimized by the requirements of this system.
        The Agency, however, has historical information that shows damage 
    to ground water and other sensitive environments has occurred during 
    the management of wastes from the dye and pigment manufacturing 
    operations. At ten dye and pigment facilities, the quality of ground 
    water has been adversely affected by waste management activities, 
    typically unlined waste trenches, aeration basins, and impoundments. 
    One dye company had to purchase the deeds to three nearby residences 
    and a gas station because VOC-contaminated ground water originating 
    from the plant had contaminated surrounding drinking water wells. At 
    another dye facility, a contaminated ground-water plume migrated under 
    residential houses bordering the site. The residential wells, used for 
    swimming pools and irrigation systems in the neighborhood, were 
    condemned because of chemical contamination. Ground water was 
    contaminated from land treatment of dye wastewater being sprayed onto a 
    field, and passing through a layer of clay. Soil contamination near 
    drum storage pads or drum wash areas has been documented at 7 dye 
    facilities. As a result, the leachate from these soils possibly 
    contributed to the ground- water contamination associated with many of 
    the sites. Concentrations of volatile and semi-volatile organic 
    compounds have been found in soils surrounding an on-site landfill at a 
    dye facility. Finally, dye and pigment facilities are found on the 
    Superfund National Priority List; further evidence that mismanagement 
    of dye and pigment wastes have the potential to yield threats of 
    concern to human health. In summary, although difficult to quantify 
    precisely, a benefit of today's proposal is the prevention of 
    additional or similar incidents occurring from similar management 
    practices of dye and pigment wastes that potentially could degrade the 
    quality of ground water or other sensitive natural resources.
        In addition to the reduction of human health risk associated with 
    the mismanagement of dye and pigment wastes proposed for listing in 
    this rulemaking, there are a number of other benefits that are even 
    more difficult to quantify.
        The Subtitle C management framework for generators and permitted 
    treatment storage and disposal facilities establishes standards for 
    hazardous waste handling, management, and remediation that: Reduce 
    ecological risks, reduce natural resource damage, reduce the likelihood 
    and severity of accidents, improve worker safety, promote facility-wide 
    remedial programs, insure that adequate financial assurance is 
    established to handle protective closure of waste management units, 
    increase public participation, improve information availability on 
    waste quantity and movement, ensure minimum uniform national standards, 
    and create incentives for pollution prevention.
    
    Ecological and Natural Resource Damage Reduction
    
        The risk assessment for this listing has focused on the human 
    health risks associated with plausible management of dye and pigment 
    wastes. An additional concern, given the proximity of several 
    facilities to surface waters and their associated wetland systems, is 
    the potential for ecological damages to biota inhabiting surface waters 
    and wetlands. In some cases migration to the surface water may be 
    occurring via groundwater. EPA requests comments regarding the 
    potential for ecological damages associated with the wastes proposed 
    for listing in today's rulemaking.
        In addition to direct ecological and human health damage there is 
    evidence from EPA's contaminant fate and transport modelling and case 
    studies of ground water, surface water, and soil degradation. While use 
    of and human exposure to these natural resources may not be occurring 
    now, their use in the future could be limited if they are contaminated. 
    The Subtitle C waste management program will limit future releases and 
    prevent natural resource damages. These benefits have not been 
    quantified.
    
    Reduce the Likelihood and Severity of Accidents
    
        An important component of the Subtitle C system for both generators 
    and permitted treatment, storage and disposal facilities is the need to 
    establish waste analysis plans, contingency plans, emergency 
    procedures, inspection programs, construction quality assurance and 
    personnel training programs. In addition, permitted facilities also 
    must have in place inspection programs and location standards. The 
    costs of these programs have been included in the cost analysis, but 
    the benefits are difficult to quantify. These Subtitle C programs may 
    reduce risk to workers and nearby populations by reducing the chance of 
    contaminant releases, accidental exposures, and catastrophic failures. 
    In the event that accidents occur, these Subtitle C provisions increase 
    the likelihood of quick action and ensure protection of human health 
    and the environment. There are other programs that require similar 
    planning (e.g., OSHA, Section 112(r) of the Clean Air Act) and 
    indirectly affect hazardous waste handling; RCRA regulatory provisions 
    deal directly with accident prevention standards associated with the 
    handling of hazardous wastes.
    
    Promote Facility-Wide Remedial Programs
    
        Those facilities that choose to obtain Part B permits for the 
    treatment, storage and disposal of hazardous wastes will have the 
    responsibility of ensuring that adequate corrective action programs are 
    in place to control releases from all solid waste management units. The 
    cost analysis included an evaluation of the cost of facility-wide 
    corrective action while the risk assessment focused only on the risks 
    associated with hazardous waste management units. Although difficult to 
    quantify, there are risk-reduction benefits associated with the cleanup 
    of releases from the solid waste management units in addition to those 
    benefits associated with the handling of listed waste.
    
    Financial Assurance To Insure Protective Closure of Waste Management 
    Units
    
        Permitted facilities are required to support financial mechanisms 
    which ensure that adequate funds are available to close hazardous waste 
    treatment, storage and disposal units in a manner that ensures long-
    term protection of human health and the environment. The costs of those 
    financial assurance requirements have been included in the cost 
    analysis; however, the benefits are difficult to quantify. Financial 
    assurance has the benefit of insuring that owners and operators of 
    hazardous waste facilities have sufficient financial resources to close 
    their facilities in an environmentally-protective manner.
    
    Increase Public Participation and Improve Information Availability
    
        The Subtitle C system has the benefit of providing the information 
    needed to empower local communities and waste managers, those most 
    affected by and able to improve substandard waste management practices. 
    The public participation provisions of the Subtitle C system ensure 
    that information is provided to stakeholders regarding the risks to 
    human health and the environment of a new or expanding waste management 
    facility. Biennial reporting, required of all large quantity generators 
    of hazardous waste, allows for more informed waste management decisions 
    and capacity management. Finally, the manifest system, which is used to 
    track the movement of wastes, ensures protective handling of hazardous 
    wastes as they move in commerce.
    
    IX. Executive Order 12866
    
        Executive Order 12866 requires that regulatory agencies determine 
    whether a new regulation constitutes a significant regulatory action. A 
    significant regulatory action is defined as an action likely to result 
    in a rule that may:
         Have an annual effect on the economy of $100 million or 
    more, or adversely affect in a material way the economy, a sector of 
    the economy, productivity, competition, jobs, the environment, public 
    health or safety, or state, local, or tribal governments or 
    communities;
         Create a serious inconsistency or otherwise interfere with 
    an action taken or planned by another agency;
         Materially alter the budgetary impact of entitlements, 
    grants, user fees, or loan programs or rights and obligations of 
    recipients thereof; or
         Raise novel legal or policy issues arising out of legal 
    mandates, the President's priorities, or the principles set forth in 
    Executive Order 12866.
        EPA estimated the costs of the proposed listings and evaluated the 
    other factors above to determine if this proposed rule making would be 
    a major regulation as defined by the Executive Order. Today's proposed 
    rule is estimated to have an annualized incremental cost of less than 
    $19 million. Based on EPA's analysis of the other factors, today's 
    proposed rule is considered a significant regulatory action because of 
    the novel policy issues contained herein. As a significant regulatory 
    action, it has been submitted to and reviewed by the Office of 
    Management and Budget.
    
    X. Regulatory Flexibility Act
    
        The Regulatory Flexibility Act (RFA) of 1980 requires Federal 
    agencies to consider ``small entities'' throughout the regulatory 
    process. Section 603 of the RFA requires an initial screening analysis 
    to be performed to determine whether small entities will be affected by 
    the regulation. If affected small entities are identified, regulatory 
    alternatives that mitigate the potential impacts must be considered. 
    Small entities as described in the Act are only those ``businesses, 
    organizations and governmental jurisdictions subject to regulation.''
        For SIC 2865, Cyclic Crudes and Intermediates, the Small Business 
    Administration defines small entities as those firms employing less 
    than or equal to 750 employees. Based on this employment cutoff, 
    approximately 61 percent, or 20 of the 33 affected dye and/or pigment 
    manufacturers (i.e., companies) are considered small entities. Under 
    the listing alternative, which assumes disposal of wastewater treatment 
    sludges/solids in an off-site commercial Subtitle C landfill and 
    management of wastewaters in tanks, 7 of the 33 affected companies are 
    estimated to incur potential significant economic impacts. Four of the 
    7 companies estimated to incur potential significant economic impacts 
    are small entities. Although small entities are predominant in the 
    affected industry, the proposed listings do not adversely affect small 
    entities to a greater extent than large entities.
        Under the Agency's Revised Guidelines for Implementing the 
    Regulatory Flexibility Act, the Agency is committed to considering 
    regulatory alternatives in rulemakings when there are any estimated 
    economic impacts on small entities. The Agency obtained firm level 
    employment data for the purpose of identifying and evaluating economic 
    impacts on small entities. The statutory requirements of the RCRA 
    program do not provide legal avenues to grant relief from the proposed 
    listings to small entities. Because of statutory restrictions, the 
    Agency is unable to exempt small entities or develop options to reduce 
    economic impacts on small entities. The Agency must identify waste 
    streams for listing without regard to the size of the entity being 
    regulated. However, the possibility of enforceable agreements described 
    previously may ameliorate the impact of listing on small entities.
    
    XI. Paperwork Reduction Act
    
        This rule does not contain any new information collection 
    requirements subject to OMB review under the Paperwork Reduction Act of 
    1980, 44 U.S.C. 3501 et seq. Facilities will have to comply with the 
    existing Subtitle C record keeping and reporting requirements for the 
    newly listed wastestreams.
        To the extent that this rule imposes any information collection 
    requirements under existing RCRA regulations promulgated in previous 
    rule makings, those requirements have been approved by the Office of 
    Management and Budget (OMB) under the Paperwork Reduction Act, 44 
    U.S.C. 3501 et seq., and have been assigned OMB control numbers 2050-
    120 (ICR no. 1573, Part B Permit Application); 2050-120 (ICR 1571, 
    General Facility Standards); 2050-0028 (ICR 261, Notification to Obtain 
    an EPA ID); 2050-0034 (ICR 262, Part A Permit Application); 2050-0039 
    (ICR 801, Hazardous Waste Manifest); 2050-0035 (ICR 820, Generator 
    Standards); and 2050-0024 (ICR 976, Biennial Report).
        Release reporting required as a result of listing wastes as 
    hazardous substances under CERCLA and adjusting the reportable 
    quantities (RQs) has been approved under the provisions of the 
    Paperwork Reduction Act, 44 U.S.C. 3501 et seq., and has been assigned 
    OMB control number 2050-0046 (ICR 1049, Notification of Episodic 
    Release of Oil and Hazardous Substances).
    
    List of Subjects
    
    40 CFR Part 261
    
        Environmental protection, Hazardous materials, Waste treatment and 
    disposal, Recycling.
    
    40 CFR Part 271
    
        Environmental protection, Administrative practice and procedure, 
    Confidential business information, Hazardous material transportation, 
    Hazardous waste, Indians-lands, Intergovernmental relations, Penalties, 
    Reporting and recordkeeping requirements, Water pollution control, 
    Water supply.
    
    40 CFR Part 302
    
        Environmental protection, Air pollution control, Chemicals, 
    Emergency Planning and Community Right-to-Know Act, Extremely hazardous 
    substances, Hazardous chemicals, Hazardous materials, Hazardous 
    materials transportation, Hazardous substances, Hazardous wastes, 
    Intergovernmental relations, Natural resources, Pesticides and pests, 
    Reporting and recordkeeping requirements, Superfund, Waste treatment 
    and disposal, Water pollution control, Water supply.
    
        Dated: December 5, 1994.
    Carol M. Browner,
    Administrator.
    
        For the reasons set out in the preamble, it is proposed to amend 
    title 40 of the Code of Federal Regulations as follows:
    
    PART 261--IDENTIFICATION AND LISTING OF HAZARDOUS WASTE
    
        1. The authority citation for Part 261 continues to read as 
    follows:
    
        Authority: 42 U.S.C. 6905, 6912(a), 6921, 6922, and 6938.
        2. In Sec. 261.32, the table is amended by adding the subgroup 
    ``Organic dyes and pigments,'' and adding to this subgroup the 
    following wastestreams:
    
    
    Sec. 261.32  Hazardous wastes from specific sources.
    
    * * * * *
    
    ------------------------------------------------------------------------
      Industry and EPA                                               Hazard 
     hazardous waste No.               Hazardous waste                code  
    ------------------------------------------------------------------------
                                                                            
                                  * * * * * * *                             
    Organic dyes and                                                        
     pigments:                                                              
                                                                            
                                  * * * * * * *                             
    K162................  Wastewater treatment sludge from the      (T)     
                           production of azo pigments.                      
    K163................  Wastewaters from the production of azo    (T)     
                           pigments.                                        
    K164................  Wastewater treatment sludge from the      (T)     
                           production of azo dyes, excluding FD&C           
                           colorants.                                       
    K165................  Wastewaters from the production of azo    (T)     
                           dyes, excluding FD&C colorants.                  
    K166................  Still bottoms or heavy ends from the      (T)     
                           production of triarylmethane dyes or             
                           pigments.                                        
                                                                            
                                  * * * * * * *                             
    ------------------------------------------------------------------------
    
    Appendix VII to Part 261  [Amended]
    
        3. Appendix VII to Part 261 is amended by adding the following 
    wastestreams in alphanumeric order (by the first column) to read as 
    follows:
    
                 Appendix VII--Basis For Listing Hazardous Waste            
    ------------------------------------------------------------------------
     EPA hazardous waste No.      Hazardous constituents for which listed   
    ------------------------------------------------------------------------
                                                                            
                                  * * * * * * *                             
    K162.....................  Aniline, 2-aminoaniline, 4-aminoaniline, 2-  
                                methoxyaniline, 2-aminotoluene, 4-          
                                aminotoluene, acetoacet-o-anisidide,        
                                acetoacet-o-toluidide, acetoacetanilide, 1,3-
                                dinitrobenzene, 3,3'dimethylbenzidine,      
                                nitrobenzene, 2,4-dinitrophenol.            
    K163.....................  2-aminoaniline, 4-aminoaniline, 2-           
                                methoxyaniline, 2-aminotoluene, 3-          
                                aminotoluene, 4-aminotoluene, aniline,      
                                acetoacet-o-anisidide, acetoacet-o-         
                                toluidide, acetoacetanilide, 2,4-           
                                dimethylaniline, 2,6-dimethylaniline.       
    K164.....................  2-aminoaniline, 4-aminoaniline, 2-           
                                methoxyaniline, aniline, diphenylamine, N-  
                                nitrosodiphenylamine, 3,3'-                 
                                dimethoxybenzidine, 4-methylphenol, 1,3-    
                                dinitrobenzene, 2-methoxy-5-nitroaniline,   
                                2,4-dinitrophenol, 2-aminotoluene, 4-       
                                aminotoluene.                               
    K165.....................  2-aminoaniline, 4-aminoaniline, 2-           
                                methoxyaniline, 2-aminotoluene, 3-          
                                aminotoluene, 4-aminotoluene, aniline.      
    K166.....................  1,2-diphenylhydrazine, azobenzene, aniline,  
                                diphenylamine, N-nitrosodiphenylamine.      
                                                                            
                                  * * * * * * *                             
    ------------------------------------------------------------------------
    
    Appendix VIII to Part 261 [Amended]
    
        4. Appendix VIII to Part 261 is amended by adding the following 
    hazardous constituents in alphabetical order to read as follows:
    
    ----------------------------------------------------------------------------------------------------------------
                                                                                            Chemical                
                   Common name                          Chemical abstracts name            abstracts     Hazardous  
                                                                                              No.        waste No.  
    ----------------------------------------------------------------------------------------------------------------
                                                                                                                    
                                                      * * * * * * *                                                 
    Acetoacetanilide.........................  Butanamide, 3-oxo-N-phenyl-..............     102-01-2  .............
    Acetoacet-o-anisidide....................  Butanamide, N-(2-methoxyphenyl)-3-.......      92-15-9  .............
    Acetoacet-o-toluidide....................  Butanamide, N-(2-methylphenyl)-3-oxo-....      93-68-5  .............
                                                                                                                    
                                                      * * * * * * *                                                 
    2-Aminoaniline...........................  Benzenediamine, 1,2-.....................      95-54-5  .............
    4-Aminoaniline...........................  Benzenediamine, 1,4-.....................     106-50-3  .............
                                                                                                                    
                                                      * * * * * * *                                                 
    3-Aminotoluene...........................  Benzenamine, 3-methyl-...................     108-44-1  .............
                                                                                                                    
                                                      * * * * * * *                                                 
    Azobenzene...............................  Azobenzene...............................     103-33-3  .............
                                                                                                                    
                                                      * * * * * * *                                                 
    2,4-Dimethylaniline......................  Benzenamine, 2,4-dimethyl-...............      95-68-1  .............
    2,6-Dimethylaniline......................  Benzenamine, 2,6-dimethyl-...............      87-62-7  .............
                                                                                                                    
                                                      * * * * * * *                                                 
    1,3-Dinitrobenzene.......................  Benezene, 1,3-dinitro-...................      99-65-0  .............
                                                                                                                    
                                                      * * * * * * *                                                 
    2-Methoxyaniline.........................  Benzenamine, 2-methoxy-..................      90-04-0  .............
                                                                                                                    
                                                      * * * * * * *                                                 
    2-Methoxy-5-nitroaniline.................  Benzenamine, 2-methoxy-5-nitro...........      99-59-2  .............
                                                                                                                    
                                                      * * * * * * *                                                 
    4-Methylphenol...........................  Phenol, 4-methyl-........................     106-44-5  .............
                                                                                                                    
                                                      * * * * * * *                                                 
    N-Nitrosodiphenylamine...................  N-Nitrosodiphenylamine...................      86-30-6  .............
                                                                                                                    
                                                      * * * * * * *                                                 
    ----------------------------------------------------------------------------------------------------------------
    
    * * * * *
    
    PART 271--REQUIREMENTS FOR AUTHORIZATION OF STATE HAZARDOUS WASTE 
    PROGRAMS
    
        5. The authority citation for Part 271 continues to read as 
    follows:
    
        Authority: 42 U.S.C. 6905, 6912(a), and 6926.
    
        6. Section 271.1(j) is amended by adding the following entry to 
    Table 1 in chronological order by date of publication to read as 
    follows.
    
    
    Sec. 271.1  Purpose and scope.
    
    * * * * *
        (j) * * *
    
                   Table 1--Regulations Implementing the Hazardous and Solid Waste Amendments of 1984               
    ----------------------------------------------------------------------------------------------------------------
         Promulgation date           Title of regulation      Federal Register reference        Effective date      
    ----------------------------------------------------------------------------------------------------------------
                                                                                                                    
                                                      * * * * * * *                                                 
    December 22, 1994..........  Listing Wastes from the      [Insert Federal Register    [Insert effective date].  
                                  Production of Dyes and       page in numbers].                                    
                                  Pigments.                                                                         
                                                                                                                    
                                                      * * * * * * *                                                 
    ----------------------------------------------------------------------------------------------------------------
    
    PART 302--DESIGNATION, REPORTABLE QUANTITIES, AND NOTIFICATION
    
        7. The authority citation for Part 302 continues to read as 
    follows:
    
        Authority: 42 U.S.C. 9602, 9603, and 9604; 33 U.S.C. 1321 and 
    1361.
    
    
    Sec. 302.4  [Amended]
    
        8. Section 302.4 is amended by adding the following entries to 
    Table 302.4 to read as follows. The appropriate footnotes to Table 
    302.4 are republished without change.
    * * * * *
    
                          Table 302.4.--List of Hazardous Substances and Reportable Quantities                      
    ----------------------------------------------------------------------------------------------------------------
                                                                         Statutory                  Final RQ        
                                                                ----------------------------------------------------
             Hazardous substance            CASRN    Regulatory                      RCRA                           
                                                      synonyms      RQ     Code+    Waste     Category   Pounds (Kg)
                                                                                     No.                            
    ----------------------------------------------------------------------------------------------------------------
                                                                                                                    
                                                      * * * * * * *                                                 
    K162Wastewater treatment sludge from                                                                            
     the production of azo pigments......  .......  ...........       1*        4     K162                          
    K163Wastewaters from the production                                                                             
     of azo pigments.....................  .......  ...........       1*        4     K163                          
    K164Wastewater treatment sludge from                                                                            
     the production of azo dyes,                                                                                    
     excluding FD&C colorants............  .......  ...........       1*        4     K164                          
    K165Wastewaters from the production                                                                             
     of azo dyes, excluding FD&C                                                                                    
     colorants...........................  .......  ...........       1*        4     K165                          
    K166Still bottoms or heavy ends from                                                                            
     the production of triarylmethane                                                                               
     dyes or pigments....................  .......  ...........       1*        4     K168                          
                                                                                                                    
                                                      * * * * * * *                                                 
    ----------------------------------------------------------------------------------------------------------------
    +--Indicates the statutory source as defined by 1, 2, 3, and 4 below.                                           
    4--Indicates that the statutory source for designation of this hazardous substance under CERCLA is RCRA Section 
      3001.                                                                                                         
    1*--Indicates that the 1 pound RQ is a CERCLA statutory RQ.                                                     
    
    [FR Doc. 94-30767 Filed 12-21-94; 8:45 am]
    BILLING CODE 6560-50-P
    
    
    

Document Information

Published:
12/22/1994
Entry Type:
Uncategorized Document
Action:
Notice of proposed rulemaking.
Document Number:
94-30767
Dates:
EPA will accept public comments on this proposed rule and on EPA's hazardous waste listing determination policy until March 22, 1995. Comments postmarked after this date will be marked ``late'' and may not be considered. Any person may request a public hearing on this
Pages:
0-0 (1 pages)
Docket Numbers:
Federal Register: December 22, 1994
CFR: (3)
40 CFR 261.32
40 CFR 271.1
40 CFR 302.4