99-22937. Approval and Promulgation of State Implementation Plans; Colorado; Revisions to Opacity and Sulfur Dioxide Requirements  

  • [Federal Register Volume 64, Number 170 (Thursday, September 2, 1999)]
    [Proposed Rules]
    [Pages 48127-48135]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 99-22937]
    
    
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    ENVIRONMENTAL PROTECTION AGENCY
    
    40 CFR Part 52
    
    [CO-001-0031; FRL-6432-7]
    
    
    Approval and Promulgation of State Implementation Plans; 
    Colorado; Revisions to Opacity and Sulfur Dioxide Requirements
    
    AGENCY: Environmental Protection Agency (EPA).2
    ACTION: Proposed rule.
    
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    SUMMARY: On May 27, 1998, the Governor of Colorado submitted revisions 
    to the State Implementation Plan (SIP). Specifically, the State 
    submitted revisions to Colorado Regulation No. 1 to provide coal-fired 
    electric utility boilers with certain exemptions from the State's pre-
    existing limitations on opacity and sulfur dioxide (SO2) 
    emissions during periods of startup, shutdown, and upset. The EPA is 
    proposing to disapprove these revisions to the Colorado SIP because the 
    revisions are not consistent with the Clean Air Act (Act) and 
    applicable Federal requirements. The effect of this disapproval will be 
    that the previous version of Colorado Regulation No. 1 (which did not 
    contain any exemptions from the SO2 emission limitations and 
    which generally provided for a 30% opacity limit during periods of 
    startup, as well as fire building, cleaning of fire boxes, soot 
    blowing, process modification, or adjustment of control equipment) will 
    remain part of the Federally enforceable SIP.2
    DATES: Written comments must be received on or before October 4, 1999.2
    ADDRESSES: Written comments may be mailed to Richard R. Long, Director, 
    Air and Radiation Program, Mailcode 8P-AR, Environmental Protection 
    Agency (EPA), Region VIII, 999 18th Street, Suite 500, Denver, Colorado 
    80202-2466. Copies of the documents relevant to this action are 
    available for public inspection during normal business hours at the Air 
    and Radiation Program, Environmental Protection Agency, Region VIII, 
    999 18th Street, Suite 500, Denver, Colorado 80202-2466. Copies of the 
    State documents relevant to this action are available for public 
    inspection at the Air Pollution Control Division, Colorado Department 
    of Public Health and Environment, 4300 Cherry Creek Drive South, 
    Denver, Colorado 80222-1530.2
    FOR FURTHER INFORMATION CONTACT: Vicki Stamper, EPA Region VIII, (303) 
    312-6445.2
    SUPPLEMENTARY INFORMATION:
    
    Table of Contents
    
    I. Background of Submittal
        A. Revisions to Opacity Standards
        B. Revisions to SO2 Emission Limitations
    II. EPA's Analysis of State's Submittal
        A. Procedural Background
        B. Analysis of State's Submittal
        1. It Does Not Appear the State Has Adequately Addressed the 
    Requirements of Section 193 of the Act
        2. It Does Not Appear the State Has Adequately Addressed the 
    Requirements of Section 110(l) of the Act
        3. It Does Not Appear the State Has Addressed the Requirements 
    of 40 CFR 51.166(a)(2)
        4. The SIP Revision Does Not Appear to Meet the Act's 
    Requirements That SIP Measures Be Enforceable
        5. The SIP Revision Appears To Be Inconsistent With the 
    Requirements of the Act Regarding Continuous Compliance
        6. EPA Invites Comment on Whether the SIP Revision Conflicts 
    With EPA's Any Credible Evidence Rule
    III. Proposed Action
    IV. Administrative Requirements
        A. Executive Order 12866
        B. Executive Order 12875
        C. Executive Order 13045
        D. Executive Order 13084
        E. Regulatory Flexibility Act
        F. Unfunded Mandates
    
    I. Background of State Submittal
    
        On May 27, 1998, the Governor of Colorado submitted revisions to 
    the Colorado SIP. The SIP submittal consisted of revisions to Colorado 
    Regulation No. 1 to provide exemptions from the existing limitations on 
    opacity and SO2 emissions for coal-fired electric utility 
    boilers during periods of startup, shutdown, and upset.
        These revisions were adopted by the Colorado Air Quality Control 
    Commission (AQCC) on December 23, 1996. The revisions became effective 
    at the State level on March 2, 1997 for most sources. However, for 
    coal-fired electric utility boilers located within the Denver Metro PM-
    10 non-attainment area, the AQCC specified that the provisions will not 
    become State-effective until EPA issues a final rule adopting the 
    revisions to Regulation No. 1 as a permanent part of the SIP.
        The following explains in detail the revisions to Regulation No. 1 
    that the Governor submitted on May 27, 1998:
    
    A. Revisions to Opacity Standards
    
        Prior to these revisions to Regulation No. 1, sections II.A.1. and 
    4. of Regulation No. 1 generally required all sources to meet a 20% 
    opacity limit, except during periods of fire building, cleaning of fire 
    boxes, soot blowing, startup, process modification, or adjustment of 
    control equipment. During these periods, a 30% opacity limit applied, 
    except the regulation allowed one 6-minute period in excess of 30% 
    opacity in any sixty consecutive minutes. (In both the revised 
    Regulation No. 1 and the pre-existing Regulation No. 1, compliance with 
    the opacity limits is based on a six-minute average.) The revisions to 
    Regulation No. 1 that the Governor submitted on May 27, 1998 amended 
    these opacity requirements for coal-fired electric utility boilers. 
    Specifically, the State
    
    [[Page 48128]]
    
    added a provision in section II.A.10. of Regulation No. 1 governing 
    opacity at coal-fired electric utility boilers during startup, 
    shutdown, and upset. (Colorado defines ``upset conditions'' in its 
    Common Provisions Regulation as ``an unpredictable failure of air 
    pollution control or process equipment which results in the violation 
    of emission control regulations and which is not due to poor 
    maintenance, improper or careless operations, or is otherwise 
    preventable through exercise of reasonable care.'') Section II.A.10. 
    provides that, during periods of startup, shutdown, and upset, owners 
    and operators of coal-fired electric utility boilers must, to the 
    extent practicable, maintain and operate each such source including 
    associated air pollution control equipment in a manner consistent with 
    good air pollution control practice for minimizing emissions. This 
    provision also states that determination of whether acceptable 
    operating and maintenance procedures are being used will be based on 
    information available to the State, including monitoring results, 
    opacity observations, review of operating and maintenance procedures, 
    operator training, and inspection of the source.
        Another provision in section II.A.10.c. of Regulation No. 1 states 
    that a source is not being maintained and operated in accordance with 
    good air pollution control practice for minimizing emissions if the 
    source's exceedance time (excluding exceedance time related to (1) 
    significant planned maintenance outage (PMO) startups, and (2) 
    emissions associated with periods that the unit is not ``on line,'' 
    where ``on line'' is defined as fuel being fed to the boilers and the 
    fans are on) expressed as a percentage of total operating time, 
    calculated on a quarterly basis, exceeds the following ``exceedance 
    percentage time allowance:'' (1) for sources using baghouses for the 
    control of particulate matter, 0.8%; and (2) for sources using 
    electrostatic precipitators (ESPs) for the control of particulate 
    matter, 2% through March 31, 2000 and 1.5% beginning April 1, 2000. In 
    enforcing this exceedance percentage time allowance, section II.A.10.e. 
    of Regulation No. 1 provides that the State may consider each day on 
    which one or more excess emission periods occur during the remainder of 
    a given quarter, following the day on which the exceedance percentage 
    time allowance is exceeded in that quarter, to be a separate day of 
    violation for the purposes of assessing any penalties that may be 
    allowed.
        Last, a provision was added in section II.A.10.d. of Regulation No. 
    3 stating that no specific opacity limits shall be in effect for coal-
    fired electric utility boilers for the startup period following a 
    significant PMO, provided the following conditions are met:
        1. Written notification is provided to the State no less than 30 
    days prior to shutting the unit down for the PMO. The notification must 
    include a plan for minimizing emissions during the startup and an 
    estimation of the period that the control equipment will not be 
    operated while the boiler is started up;
        2. Throughout the startup following the PMO, the operator shall, to 
    the extent practicable, maintain and operate each source including the 
    associated air pollution control equipment in a manner consistent with 
    good air pollution control practice for minimizing emissions; and
        3. During any PMO startup, the source shall place any air pollution 
    control equipment in service no later than the manufacturer's 
    specifications allow.
        Section II.A.10.d. also provides that significant PMO startups 
    shall not exceed one event in any two consecutive years, and that a PMO 
    startup shall ``not normally exceed 14 days in duration,'' although the 
    State may extend this time period for good cause. Last, this provision 
    defines startup for the purposes of significant PMOs to be the period 
    of time beginning with the point of setting the unit into operation and 
    ending with the points when: (1) the generator is synchronized and is 
    operating at or greater than a specific unit's minimum load; (2) 
    primary fuel is being burned and the burners are in service without 
    stabilizing fuel being burned in the boiler; and (3) any air pollution 
    control equipment has reached minimum normal operating design 
    conditions consistent with manufacturer's specifications (as defined by 
    temperature, on a unit-by-unit basis).
    
    B. Revisions to SO2 Emission Limitations
    
        Section VI. of Regulation No. 1 contains SO2 emission limitations 
    for various source categories which vary depending on whether the 
    source was issued an emission permit before August 1, 1977 (i.e., 
    defined as an ``existing source'') or issued an emissions permit on or 
    after August 1, 1977 (i.e., defined as a ``new source''). Before the 
    revisions to Regulation No. 1 that the Governor submitted on May 27, 
    1998, section VI.B.4.a. of Regulation No. 1 required new coal-fired 
    operations, including coal-fired steam generators, to meet the 
    following SO2 emission limits:
        (1) 1.2 pounds (lbs) SO2 per million British Thermal Units (BTU) of 
    coal heat input for units converted from other fuels to coal and for 
    units with a coal heat input of less than 250 million BTU per hour; and
        (2) 0.4 lbs SO2 per million BTU coal heat input for units with a 
    coal heat input of 250 million BTU per hour or greater.
        There were no exemptions from these SO2 emission limits.
        In the May 27, 1998 submittal, the State revised section VI.B.4.a. 
    to add a new subsection (iv), which states that, during periods of 
    startup, shutdown, and upset, owners and operators of coal-fired 
    electric utility boilers must, to the extent practicable, maintain and 
    operate each such source including associated air pollution control 
    equipment in a manner consistent with good air pollution practice for 
    minimizing emissions. This provision also states that determination of 
    whether acceptable operating and maintenance procedures are being used 
    will be based on information available to the State, including 
    monitoring results, opacity observations, review of operating and 
    maintenance procedures, operator training and inspection of the source. 
    The State also added a provision stating that, for those coal-fired 
    electric utility boilers subject to 40 CFR part 60, subpart Da (i.e., 
    those coal-fired electric utility boilers for which construction or 
    modification commenced after September 18, 1978), the source is not 
    being maintained and operated in accordance with good air pollution 
    control practice for minimizing emissions if the source's exceedance 
    time expressed as a percentage of total operating time, calculated on a 
    quarterly basis, exceeds 1%.
        Last, the State revised section VI.B.2. of Regulation No. 1. 
    Section VI.B.2. of Regulation No. 1 previously specified a 3-hour 
    averaging time for all new source emission standards for SO2. This 
    section further stated that any 3-hour rolling average of emission 
    rates which exceeded the emission standards in section VI.B. of 
    Regulation No. 1 would be a violation of the State's regulation. The 
    State added the phrase ``unless specified in a permit'' to the 
    beginning of this section, in order to allow the State to use the 
    permit process to specify an averaging time other than 3 hours for a 
    specific source.
    
    II. EPA's Analysis of State's Submittal
    
    A. Procedural Background
    
        The Act requires States to observe certain procedural requirements 
    in developing implementation plans and plan revisions for submission to 
    EPA. Sections 110(a)(2) and 110(l) of the Act
    
    [[Page 48129]]
    
    provides that each revision to an implementation plan submitted by a 
    State must be adopted after reasonable notice and public hearing. The 
    EPA also must determine whether a submittal is complete and therefore 
    warrants further EPA review and action (see section 110(k)(1) and 57 FR 
    13565, April 16, 1992). The EPA's completeness criteria for SIP 
    submittals are set out at 40 CFR part 51, appendix V. The EPA attempts 
    to make completeness determinations within 60 days of receiving a 
    submission. However, a submittal is deemed complete by operation of law 
    under section 110(k)(1)(B) if a completeness determination is not made 
    by EPA within six months after receipt of the submission.
        To entertain public comment on the revisions to Regulation No. 1 
    regarding coal-fired electric utility boilers, the Colorado AQCC held 
    public hearings on December 19, 20, and 23, 1996. Following the public 
    hearings, the regulation revisions were adopted by the AQCC. The 
    Governor initially submitted the revisions to EPA for approval on 
    October 31, 1997.
        EPA found the initial SIP submittal incomplete and notified the 
    State of such finding in a January 12, 1998 letter. EPA requested 
    further information from the State pertaining to the AQCC's adoption of 
    the Regulation No. 1 revisions, due to the fact that the Sierra Club 
    and other plaintiffs had challenged the revisions in State court on the 
    grounds that the AQCC had failed to follow applicable State law 
    procedures in adopting the revisions. (See Cunningham v. Colorado Air 
    Quality Control Commission, Denver District Court, Case No. 97 CV 
    1808).
        On May 27, 1998, the Governor of Colorado resubmitted the revisions 
    to Regulation No. 1 to EPA for approval. The resubmittal included a 
    letter from the Colorado Attorney General's Office opining that the 
    AQCC had followed applicable procedures in adopting the revisions. On 
    August 7, 1998, the Denver District Court issued an Order Affirming 
    Administrative Action that affirmed the AQCC's adoption of the 
    revisions.
        EPA did not issue a completeness or an incompleteness finding for 
    the May 27, 1998 SIP submittal. Thus, pursuant to section 110(k)(1)(B), 
    the May 27, 1998 submittal was deemed complete by operation of law on 
    November 29, 1998 (i.e., six months from the date of receipt).
    
    B. Analysis of State's Submittal
    
        EPA has reviewed the State's May 1998 SIP submittal against the 
    relevant requirements of the Act, Federal regulations, and EPA policy 
    and guidance. EPA has identified several issues with the State's SIP 
    revision, as follows:
    1. It Does Not Appear the State Has Adequately Addressed the 
    Requirements of Section 193 of the Act
        For SIP provisions which EPA approved before November 15, 1990, 
    section 193 prohibits SIP modifications applicable within a 
    nonattainment area unless the modification insures equivalent or 
    greater emissions reductions of the pollutant for which the area is 
    nonattainment.
        EPA approved the existing opacity and SO2 provisions in Regulation 
    No. 1 as part of the SIP prior to the enactment of the 1990 amendments 
    to the Act (i.e., prior to November 15, 1990). There are four coal-
    fired power plants in the Denver metro PM-10 nonattainment area that 
    are affected by the State's revisions. The State's SIP revisions do not 
    impact any other nonattainment area in Colorado because there are no 
    affected coal-fired power plants in any of the State's other PM-10 
    nonattainment areas, and because the State does not have any SO2 
    nonattainment areas.
        In the Denver metro PM-10 nonattainment area, SO2 emissions have 
    been determined to contribute significantly to PM-10 exceedances (see 
    section 189(e) of the Act and 58 FR 66331, December 20, 1993). However, 
    the revisions to the SO2 requirements in Regulation No. 1 only impact 
    coal-fired electric utility boilers which are subject to 40 CFR part 
    60, subpart Da, and there are no such coal-fired electric utility 
    boilers located within the Denver metro PM-10 nonattainment area. Thus, 
    the requirements of section 193 of the Act apply only to the State's 
    changes to the opacity requirements in Regulation No. 1, as they impact 
    the four coal-fired power plants in the Denver metro PM-10 
    nonattainment area.
        The AQCC concluded that the revisions to Regulation No. 1 would 
    result in at least equivalent emissions reductions as the pre-existing 
    Regulation No. 1 provisions. In other words, the AQCC believed that the 
    revisions did not represent a relaxation of the existing rule. 
    Specifically, the AQCC's Statement of Basis states the following:
    
        The regulatory change removing application of the 30% opacity 
    limit appears on first impression to relax requirements for these 
    units. However, by limiting the overall time during which the units 
    may exceed the 20% opacity limit, the Commission believes this 
    approach will result in at least the same levels of compliance with 
    the opacity standard and will likely result in lower overall 
    emissions.1
    
        \1\ The State's Statement of Basis is somewhat unclear regarding 
    the reduced application of the 30% opacity standard and the baseline 
    for analyzing whether the rule change represents a relaxation. The 
    language of the revised Regulation No. 1 appears to be clear that 
    the 30% opacity limit continues to apply to fire building, cleaning 
    of fire boxes, soot blowing, process modification, or adjustment of 
    control equipment (unless these activities occur during a 
    significant PMO startup or a period when fuel is not being fed to 
    the boiler). In its discussion of section 193 of the Act, the State 
    does not draw this distinction. The State also fails to mention 
    that, under the provisions of Regulation No. 1, sources were 
    required to meet a 20% opacity limit during shutdown.
    
        EPA does not believe the AQCC's conclusion is adequately supported. 
    The Statement of Basis explains that the State's enforcement discretion 
    has been exercised to effectively allow 5% noncompliance by electric 
    power plants. It also states that ``substantial regulatory ambiguity'' 
    in the opacity limitations that previously applied during startup and 
    other periods led to lower compliance levels. Thus, the AQCC concluded 
    that the revisions to Regulation No. 1 are substantially equivalent or 
    better in their impact on emissions because a higher rate of compliance 
    is expected under the revised Regulation No. 1.2
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        \2\ In another part of the Statement of Basis, the AQCC 
    concluded that ``the changes made in this rulemaking will not lead 
    to increased emissions in amounts substantial enough to interfere 
    with the State's programs to attain and maintain the National 
    Ambient Air Quality Standards (NAAQS) or other federal 
    requirements.'' Here, the AQCC appears to concede that increased 
    emissions will result from the rule change.
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        EPA does not agree that the State's enforcement practices under the 
    previous version of Regulation No. 1 should be taken into account in 
    determining the stringency of the previous version of the rule or in 
    determining whether a SIP modification meets the requirements of 
    section 193 of the Act. The language of Regulation No. 1, on its face, 
    did not permit sources to exceed the applicable opacity limitations up 
    to 5% of the time. Thus, the fact that the State used enforcement 
    discretion in determining which types of violations to spend resources 
    and time pursuing has no impact on whether EPA or citizens could 
    enforce the requirements of Regulation No. 1 or whether sources were 
    obligated to comply with those requirements on a continuous basis. In 
    fact, a citizens group successfully enforced the opacity provisions of 
    Regulation No. 1 for violations at a coal-fired power plant that 
    complied with the opacity limitations of Regulation No. 1 more than 95% 
    of the time. See Sierra Club
    
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    v. Public Service Company of Colorado, 894 F. Supp. 1455 (D. Colo. 
    1995).
        Application of the AQCC's rationale regarding enforcement 
    discretion would lead to an odd result: States with the least robust 
    enforcement programs could most easily meet section 193's equivalency 
    requirements. EPA does not believe Congress intended such a result when 
    it enacted section 193 of the Act.
        Further, even though the revisions to Regulation No. 1 define when 
    a coal-fired electric utility boiler is not complying with good air 
    pollution control practices for minimizing emissions by specifying an 
    exceedance percentage time allowance, there is nothing in the revisions 
    that prevents the State from continuing to use enforcement discretion 
    in implementing the new provisions. Thus, there is no guarantee that 
    this new provision will be enforced any more stringently than the 
    previous version of Regulation No. 1. In fact, section II.A.10.e. of 
    Regulation No. 1 merely states that the State may assess penalties on a 
    violation-per-day basis.
        EPA also disagrees with the AQCC's assertion that the prior version 
    of Regulation No. 1 was ambiguous. The AQCC does not explain what was 
    ambiguous about the prior version of the regulation. EPA believes the 
    previous version of Regulation No. 1 was clear in requiring a 20% 
    opacity limit to be met at all times, except for periods of fire 
    building, cleaning of fire boxes, soot blowing, startup, process 
    modification, or adjustment of control equipment. During those periods, 
    a 30% opacity limit applied, with one 6-minute period in excess of 30% 
    opacity allowed in any sixty consecutive minutes. The only provision in 
    the State's rules that explained when an exceedance would not be 
    considered to be a violation of the rules was the State's upset 
    provision in section II.E. of the Common Provisions Regulation, which 
    provided that upset conditions (as defined in the Common Provisions 
    Regulation) would not be considered to be a violation if certain 
    notification requirements were met (and, presumably, if the upset met 
    the State's definition--i.e., it was not due to poor maintenance, 
    improper or careless operation, or was otherwise preventable through 
    exercise of reasonable care).
        EPA also believes the AQCC's analysis ignores critical features of 
    the proposed revisions to Regulation No. 1. Specifically, the AQCC 
    ignores the fact that, under the revisions to Regulation No. 1, 
    exceedances of the exceedance percentage time allowance during startup, 
    shutdown, or upset conditions would not be considered violations of the 
    opacity limitation and would not be penalized for each 6-minute 
    exceedance. Instead, exceedances of the exceedance percentage time 
    allowance during startup, shutdown, or upset conditions would only be 
    considered violations of the requirement for good air pollution control 
    practice for minimizing emissions and would only be penalized on a one-
    violation-per-day basis. The prospect of fewer violations and lower 
    penalties would reduce sources' incentive to keep their emissions low 
    during startup, shutdown, and upset, and would likely lead to higher 
    emissions of PM-10 under the revised rule than under the Federally 
    approved rule.
        Also, under the State's revisions, instead of being subject to a 
    20% opacity limit during shutdowns and a 30% opacity limit during 
    startups, sources may emit up to 100% opacity during startup, shutdown, 
    and upset conditions if, to the extent practicable, they exercised good 
    air pollution control practice for minimizing emissions. These sources 
    are potentially allowed up to 43.2 hours of 100% opacity in one 
    calendar quarter, if equipped with ESPs, and up to 17.3 hours of 100% 
    opacity in one calendar quarter, if equipped with baghouses, without 
    being considered in violation of the good air pollution control 
    practice standard.
        In addition, the AQCC's analysis ignores the provision in the 
    revised regulation that exempts significant PMO startups from the 
    opacity limits. Under the revised Regulation No. 1, sources engaged in 
    a significant PMO startup could potentially emit at 100% opacity for 
    fourteen days or longer. Under the previous version of Regulation No. 
    1, emissions during a significant PMO startup would have been subject 
    to a 30%, and sometimes to a 20%, opacity limit. It appears that the 
    State's analysis fails to consider equivalency on a short-term basis, 
    such as 24 hours, that is directly relevant to the National Ambient Air 
    Quality Standards (NAAQS).
        For the reasons stated, EPA does not believe the revisions to 
    Regulation No. 1 will insure equivalent or greater reductions of PM-10 
    as required by section 193 of the Act. Thus, EPA does not believe it 
    can approve the revisions.
    2. It Does Not Appear the State Has Adequately Addressed the 
    Requirements of Section 110(l) of the Act
        Section 110(l) of the Act provides that EPA cannot approve a 
    revision to a SIP if the revision would interfere with any applicable 
    requirement concerning attainment and reasonable further progress, or 
    any other applicable requirement of the Act. Section 110(l) applies to 
    SIP revisions affecting both attainment or unclassifiable areas, as 
    well as nonattainment areas. For attainment or unclassifiable areas, 
    analysis of proposed changes under this provision should, among other 
    things, focus on the 110(a)(1) requirement for maintenance of the 
    NAAQS.
        As discussed above, the State does not consider the revisions to 
    Regulation No. 1 regarding coal-fired electric utility boilers to be a 
    relaxation of the SIP, a conclusion with which EPA disagrees. However, 
    the State's submittal did include a study commissioned by the Colorado 
    Utilities Coalition for Clean Air regarding the ambient impacts during 
    startup and shutdown at electric utility units, which the AQCC relied 
    upon in its rulemaking.3
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        \3\ The study analyzed impacts on PM-10 and PM-2.5. The recent 
    U.S. Court of Appeals decision in American Trucking Associations, 
    Inc. v. USEPA, Nos. 97-1440 and 97-1441 (D.C. Cir., May 14, 1999) 
    did not vacate the PM-2.5 standard promulgated on July 18, 1997. In 
    any event, EPA is not relying on potential adverse impacts on PM-2.5 
    as a basis to disapprove the revisions to Regulation No. 1. The D.C. 
    Circuit's decision had no impact on the pre-July 18, 1997 PM-10 
    standard. That standard remains in place in Colorado, and EPA has an 
    ongoing responsibility under the Act to ensure the standard is 
    attained and maintained.
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        EPA has reviewed the study included in the SIP submittal and has 
    found many flaws in the analysis. The study was based on startup and 
    shutdown data from four coal-fired electric utility boilers (out of 
    twenty-five in the entire State), but there was no information provided 
    to explain why these four units were chosen or how they were 
    representative of the potential ambient air issues from all of the 
    twenty-five coal-fired electric utility boilers in the State. The 
    modeling analysis projected ambient particulate matter impacts from 
    each of the four units, in addition to background PM concentrations, 
    that were less than the 24-hour PM-10 NAAQS. However, based on the 
    information submitted, it is apparent that the modeling analysis did 
    not follow the requirements contained in the EPA Guideline on Air 
    Quality Models. (See 40 CFR part 51, appendix W).
        The emissions used in the modeling demonstration did not capture 
    the potentially most adverse emissions scenarios associated with 
    startup and shutdown. For example, it appears that the modeling 
    analysis was based on actual emissions from a sample start-up/shutdown 
    sequence that was simply repeated in the model throughout the year. The 
    EPA's Guideline on Air
    
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    Quality Models requires that, in testing for compliance with 24-hour 
    standards, worst case hourly emission rates (from the test sequence) 
    must be used in the model for every hour of the year. Also, the 
    meteorological data and selection of modeling input options was 
    problematic. It appears that only one year of National Weather Service 
    meteorology data was used in the modeling analysis, while the EPA 
    Modeling Guideline requires that five years of such data be used. If 
    the additional four years of meteorology data had been used in the 
    modeling, it is likely that more adverse dispersion situations and 
    higher ambient impacts would have been predicted. Further, the modeling 
    only analyzed whether emissions from one unit, considering background 
    concentrations, would cause a violation of the NAAQS. The modeling did 
    not analyze whether the emissions from one unit during startup or 
    shutdown would contribute to a violation, considering emissions from 
    other nearby sources in the area. (Each of the units modeled in the 
    study is collocated with two to four other coal-fired electric utility 
    boilers.)
        In addition, the study only looked at particulate matter impacts, 
    and it did not address the revisions to the SO2 limits whatsoever.
        Thus, EPA believes the modeling analysis included in the SIP 
    submittal cannot be relied upon because of its overall noncompliance 
    with the EPA Guideline on Air Quality Models, nor can the Agency rely 
    on it to conclude that the SIP revision will not interfere with 
    attainment or maintenance of the NAAQS.
    3. It Does Not Appear the State Has Addressed the Requirements of 40 
    CFR 51.166(a)(2)
        40 CFR 51.166(a)(2) requires that, if a SIP revision would result 
    in increased air quality deterioration over any baseline concentration, 
    the SIP revision must include a demonstration that it will not cause or 
    contribute to a violation of the applicable increment(s). The 
    demonstration does not need to be done for those section 107 
    attainment/unclassifiable areas (as identified in 40 CFR part 81) where 
    the minor source baseline date has not been triggered prior to 
    submittal of the SIP revision, although the State is still required 
    under 40 CFR 51.166(a)(4) to periodically review the adequacy of its 
    plan to prevent significant deterioration of air quality.
        According to EPA's prevention of significant deterioration (PSD) 
    regulations, the ``baseline concentration'' represents the ambient 
    concentration that exists in the baseline area at the time of the 
    applicable minor source baseline date. The baseline concentration 
    includes the actual emissions of sources in existence on the minor 
    source baseline date, excluding (1) the actual emissions from any major 
    stationary source on which construction occurred after the ``major 
    source baseline date''--January 6, 1975 for sources of particulate 
    matter and SO2; and (2) the actual emissions increases and decreases at 
    any stationary source occurring after the minor source baseline date. 
    (See 40 CFR 51.166(b)(13).) Thus, once the minor source baseline date 
    is triggered for an area, any changes in emissions at any stationary 
    source impact the available maximum increase allowed over the baseline 
    concentration (i.e., the increment). In Colorado, the SO2 minor source 
    baseline date was triggered Statewide as of October 12, 1977 and the 
    particulate matter minor source baseline dates have been triggered for 
    a large part of the State (each ``air quality control region'' in the 
    State has a different minor source baseline date for particulate 
    matter).
        As discussed above, EPA believes the changes to the opacity 
    provisions in Regulation No. 1 represent a relaxation from existing 
    requirements that will allow increased emissions into the air. EPA also 
    believes the revisions to the SO2 provisions are a relaxation that 
    would allow more SO2 emissions into the air. Thus, in those parts of 
    Colorado where the minor source baseline date has been triggered, this 
    SIP revision would potentially allow increased deterioration over 
    baseline concentration. As discussed above, the State did not consider 
    the revised Regulation No. 1 to be a relaxation of existing emission 
    limits. Thus, the State did not address the requirements of 40 CFR 
    51.166(a)(2). However, EPA believes this SIP revision would allow 
    increased deterioration of air quality over the baseline concentration 
    in some parts of the State and, therefore, a demonstration is required 
    to show that the SIP revision will not cause or contribute to a 
    violation of the applicable increment(s).
    4. The SIP Revision Does Not Appear To Meet the Act's Requirements That 
    SIP Measures Be Enforceable
        Section 110(a)(2)(A) of the Act requires the SIP to include, among 
    other things, ``enforceable emission limitations'' [emphasis added]. 40 
    CFR 51.281 further requires that SIPs must be ``adopted as rules and 
    regulations enforceable by the State agency.'' On September 23, 1987, 
    EPA issued a memorandum entitled ``Review of State Implementation Plans 
    and Revisions for Enforceability and Legal Sufficiency.'' This memo 
    provided guidance on how to determine whether a rule or regulation was 
    enforceable. This memo also directed the EPA Regional Offices to not 
    approve SIPs or SIP revisions which fail to satisfy the enforceability 
    criteria detailed in the September 23, 1987, memo. EPA has reviewed the 
    revised Regulation No. 1 and believes that the revised rule does not 
    meet the Act's requirement that SIP measures be enforceable as EPA has 
    interpreted that requirement. EPA's reasoning is as follows:
        (a) EPA reads the revisions to Regulation No. 1 as substituting the 
    good air pollution control practice standard in section II.A.10. for 
    the opacity limits specified in sections II.A.1. and 4. during 
    startups, shutdowns, and upsets. In defining the ``exceedance 
    percentage time allowance'' in section II.A.10., the State does not 
    specify whether exceedances will be measured against the 20% opacity 
    limit of section II.A.1., the 30% opacity limit of section II.A.4., or 
    both. This lack of clarity undermines the enforceability of the 
    regulation.
        (b) The State's Regulation No. 1 revisions either fail to specify a 
    test method for evaluating a source's performance against its 
    exceedance percentage time allowance, or specify an inadequate test 
    method. Section II.A.1. of Regulation No. 1 states that visible 
    emissions shall be measured by EPA Method 9 (40 CFR part 60, appendix 
    A) in all subsections of section II.A. and B. of Regulation No. 1, 
    unless otherwise specified. Section II.A.10. does not specify any other 
    method for measuring visible emissions for the purposes of determining 
    whether a source has exceeded the exceedance allowance. If, as EPA 
    suspects, the State intended continuous opacity monitoring (COM) data 
    to be used to evaluate a source's performance against the exceedance 
    percentage time allowance, the State needed to make this explicit in 
    the regulation to ensure enforceability. In the alternative, EPA 
    believes EPA Method 9 is inadequate to evaluate a source's performance 
    against the exceedance percentage time allowance because Method 9 
    observations cannot be made on a continuous basis. The revised SO2 
    provisions in section VI.A.2. also do not specify any test method for 
    determining whether or not a source has exceeded the SO2 exceedance 
    allowance.
        (c) Regulation No. 1 specifies that section II.A.10. governs 
    opacity during startup, shutdown, and upset, but the
    
    [[Page 48132]]
    
    AQCC's Statement of Basis states that excess emissions due to fire 
    building, process modification, and adjustment of control equipment 
    will also be counted in determining compliance with the exceedance 
    allowance. It is not clear from the actual language of the rule whether 
    exceedances due to fire building, process modification, and adjustment 
    of control equipment are to be counted in determining the number of 
    exceedances in a given quarter. Thus, there is a potential 
    inconsistency between the language of the rule and the State's intent. 
    The enforceability of the State's intent, without clear rule language, 
    is questionable.
        (d) EPA's September 23, 1987, guidance memo states that there must 
    be a clear, enforceable requirement that records be kept. While there 
    is no specific provision requiring recordkeeping and reporting in 
    section II.A.10. of Regulation No. 1, section IV.G. of Regulation No. 1 
    requires recordkeeping and reporting on a quarterly basis of periods of 
    excess emissions for sources required to operate continuous emission 
    monitoring systems for opacity and/or SO2 (which applies to most of the 
    coal-fired electric utility boilers). However, Regulation No. 1 does 
    not appear to require recordkeeping and reporting of total operating 
    time on a quarterly basis. Without such information, it is not clear 
    how the State could implement the exceedance percentage time allowance. 
    Further, section IV.G. of Regulation No. 1 does not require the 
    recordkeeping and reporting of the type of information that might be 
    needed to determine (1) whether a source is being maintained and 
    operated in accordance with good air pollution control practices for 
    minimizing emissions, or (2) whether or not a source is engaged in a 
    significant PMO startup.
        (e) Significant PMO startups are not subject to an enforceable time 
    limit. Specifically, section II.A.10.d.iii. states that a significant 
    PMO startup ``shall not normally exceed 14 days in duration, but the 
    (Colorado Air Pollution Control) Division may extend this period for 
    good cause shown.'' This language constitutes a ``director's 
    discretion'' provision that undermines the enforceability of the time 
    limit and undercuts any benefit the time limit would have for 
    protecting the NAAQS.
        (f) For significant PMO startups, section II.A.10.d.i requires the 
    source to submit to the Division a plan for minimizing emissions during 
    the startup, but the revisions do not require the source to follow the 
    plan. Thus, the plan is unenforceable.
        (g) Section II.A.10.d.iii. describes the duration of significant 
    PMO startups. The duration is defined according to various events that 
    occur during the course of a startup, but it is not clear from the 
    language of the regulation that these events are adequately defined or 
    that the information needed to adequately define these events for 
    enforcement purposes is or will be available. For example, this section 
    of the regulation refers to a specific unit's minimum load. It is not 
    clear what this means or whether it is a constant and well-understood 
    value.
        (h) In the Statement of Basis for the revisions to Regulation No. 
    1, the Commission states that the significant PMO startup exception 
    ``is not intended to allow exclusion of excess emissions resulting from 
    routine maintenance outages, such as annual replacement of standard 
    equipment * * *.'' Instead, ``the Commission restricts the application 
    of the planned maintenance outage exception to events requiring 
    significant changes at the facility, such as replacement of major 
    facility components or installation of new processes * * *.'' However, 
    the language of the regulation does not restrict significant PMOs in 
    this way: Section II.A.10.d describes a significant PMO as ``a 
    scheduled, infrequent yet extended maintenance shutdown * * *.'' Thus, 
    it does not appear that the restriction the AQCC intended is 
    enforceable.
        (i) The State revised section VI.B.2. of Regulation No. 1 to allow 
    a permit to specify a different averaging time for SO2 limits than the 
    3-hour averaging time contained in the regulation. This revision would 
    allow the State to change the Federally enforceable averaging time in 
    the SIP without EPA approval or Federal notice and comment rulemaking. 
    EPA is unwilling to approve such a director's discretion provision, 
    because it undermines the enforceability of the regulatory limit and 
    allows the State to change the SIP without meeting the Act's 
    requirements for SIP revisions. EPA believes it is impossible to judge 
    in advance whether the State's potential changes to averaging times 
    under such an open-ended provision would be consistent with maintenance 
    of the NAAQS. In addition, EPA generally cannot approve a SIP provision 
    that would be inconsistent with the averaging time of the NAAQS the SIP 
    provision is designed to protect. Thus, to ensure protection of the 
    secondary SO2 NAAQS, EPA believes the averaging time must not be longer 
    than three hours, and EPA cannot approve a discretionary provision in 
    the SIP that might allow averaging times longer than three hours.
        (j) Section VI.B.4.a.(iv) of Regulation No. 1 states that, during 
    periods of startup, shutdown, and upset, owners and operators of coal-
    fired electric utility boilers shall maintain and operate such sources 
    in accordance with good air pollution control practice for minimizing 
    emissions. However, the regulation does not state that such sources are 
    exempt from the SO2 emission limit during startup, shutdown, and upset. 
    Thus, the regulation reads as if both the SO2 emission limit and the 
    good air pollution control practice standard apply during startup, 
    shutdown, and upset at coal-fired electric utility boilers. However, 
    the AQCC's Statement of Basis strongly implies that the good air 
    pollution control practice standard applies in place of the SO2 
    emission limitation. This discrepancy between the Statement of Basis 
    and the regulation creates confusion and undermines the enforceability 
    of the regulation.
        In addition to the above issues, section II.A.10.e. of Regulation 
    No. 1 states that, in enforcing the exceedance percentage time 
    allowance for opacity, the State may consider each day on which one or 
    more excess emission periods occur following the day on which the 
    exceedance percentage time allowance is exceeded for that quarter to be 
    a separate day of violation for the purposes of assessing any penalties 
    that may be allowed. This is much less stringent than considering each 
    six-minute average of excess emissions a separate violation, as was 
    previously required under the State's Regulation No. 1. Thus, the 
    compliance incentive during startup, shutdown, and upset will be 
    substantially reduced. This will, in turn, reduce the effectiveness of 
    the rule in controlling particulate emissions.
        In summary, EPA does not believe that the revisions to Regulation 
    No. 1 meet the Act's requirements that SIP measures be enforceable.
    5. The SIP Revision Appears To Be Inconsistent With the Requirements of 
    the Act Regarding Continuous Compliance
        The Act requires continuous compliance with emission limitations to 
    ensure continuous protection of public health and the environment. The 
    exemptions the State has written into Regulation No. 1 eliminate the 
    requirement in the SIP that coal-fired electric utility boilers comply 
    with Regulation No. 1's opacity and SO2 limits on a continuous basis. 
    Under the
    
    [[Page 48133]]
    
    State's revisions to Regulation No. 1, emissions during startup, 
    shutdown, upset, significant PMO startups and certain other conditions 
    are automatically exempted from the otherwise applicable opacity and 
    SO2 limits, and are subject to no emission limit. Consistent with its 
    interpretation that emission limits must be met continuously, EPA has 
    interpreted the Act to not permit SIP revisions that automatically 
    exempt sources from emission limits.
        More specifically, section 110(a)(1) of the Act requires SIPs to 
    provide for attainment and maintenance of the NAAQS. Because the NAAQS 
    are health and welfare-based standards, Congress intended that they 
    must be met continuously, not just intermittently. Accordingly, section 
    110(a)(2) of the Act requires SIPs to contain enforceable emission 
    limitations, and section 302(k) of the Act defines ``emission 
    limitations'' as a requirement ``which limits the quantity, rate, or 
    concentration of emissions of air pollutants on a continuous basis'' 
    [emphasis added].
        EPA explained its interpretation of the term ``continuous 
    compliance'' in a June 21, 1982 memorandum from Kathleen M. Bennett, 
    Assistant Administrator for Air, Noise, and Radiation, to the Regional 
    Air Division Directors. That guidance states that ``continuous 
    compliance is essentially the avoidance of preventable excess emissions 
    over time as a result of the proper design, operation, and maintenance 
    of an air pollution source.'' The guidance also emphasizes that excess 
    emissions resulting from malfunctions or other emergency situations 
    must be minimized and terminated quickly.
        On September 28, 1982 and February 15, 1983, EPA issued policy 
    statements regarding exemptions from emission limitations during 
    startup, shutdown, and malfunction, based on EPA's interpretation of 
    the Act's requirements for continuous compliance and attainment and 
    maintenance of the NAAQS.4 For most situations, these 
    policies indicate that all excess emissions must be considered 
    violations, which may or may not be enforced based on the exercise of 
    enforcement discretion. These policies also indicate that events like 
    startup, shutdown, and maintenance are part of the normal operation of 
    a source and should be accounted for in the planning, design, and 
    implementation of operating procedures for the process and control 
    equipment.
    ---------------------------------------------------------------------------
    
        \4\ See September 28, 1982 and February 15, 1983 Memorandums, 
    both entitled ``Policy on Excess Emissions During Startup, Shutdown, 
    and Malfunctions'', from Kathleen M. Bennett, Assistant 
    Administrator for Air, Noise, and Radiation, to the Regional 
    Administrators.
    ---------------------------------------------------------------------------
    
        EPA realizes that a few sources cannot avoid short periods of 
    excess emissions during startup and shutdown, despite careful and 
    prudent planning and design. For these few sources, the February 15, 
    1983 policy states that excess emissions during these infrequent, short 
    periods need not be treated as violations provided that the source 
    adequately shows that the excess could not have been prevented through 
    careful planning and design and that bypassing of control equipment was 
    unavoidable to prevent loss of life, personal injury, or severe 
    property damage. Similarly, excess emissions during periods of 
    scheduled maintenance should be treated as a violation, unless a source 
    can demonstrate that such emissions could not have been avoided through 
    better scheduling for maintenance or through better operation and 
    maintenance practices.
        These policy statements are consistent with EPA's view that SIP 
    limits must be met continuously because they are intended to protect 
    the NAAQS; any exceptions should be narrowly drawn and clearly place 
    the burden on the source to demonstrate that an exceedance was 
    unavoidable. EPA believes the revisions to Regulation No. 1 are 
    inconsistent with the Act's requirement for continuous compliance and 
    attainment and maintenance of the NAAQS, and believes the revisions 
    must be disapproved.
        The revisions eliminate the requirement for coal-fired electric 
    utility boilers to meet any opacity limit during periods of startup, 
    shutdown, and upset. It appears the State intended to provide the same 
    exemption for SO2 limits. Instead, during these periods, coal-fired 
    electric utility boilers are only obligated to exercise good air 
    pollution control practice for minimizing emissions.
        As noted in the Background section, above, the revisions establish 
    an ``exceedance percentage time allowance.'' The exceedance of this 
    exceedance percentage time allowance in a quarter is considered a 
    violation of the duty to exercise good air pollution control practice 
    for minimizing emissions. However, it is not considered a violation of 
    the underlying emission limit, and violations may only be penalized on 
    a per-day basis.
        With respect to SO2 limits, Regulation No. 1 does not specify how 
    the State will treat exceedances of the exceedance allowance described 
    in section VI.B.4.a.(iv)(B) of Regulation No. 1, but it appears the 
    State intends to approach such exceedances in the same manner as 
    exceedances of the opacity exceedance percentage time allowance.
        In order to ensure continuous compliance with the SIP's opacity and 
    SO2 limits, EPA believes it is essential that exceedances during 
    startup, shutdown, and upsets be considered violations of such limits, 
    that may only be excused in an enforcement action if the source 
    properly demonstrates that the exceedances were unavoidable.
        EPA has the same objection to the SIP revision's exemption of 
    emissions during significant PMO startups and periods when fuel is not 
    being fed to the boiler. For significant PMO startups, revised 
    Regulation No. 1 requires sources to exercise good air pollution 
    control practices for minimizing emissions but states that no opacity 
    limit applies during these periods. As noted above, significant PMO 
    startups may last 14 days or longer. For emissions during periods when 
    fuel is not being fed to the boiler, the revisions do not appear to 
    impose any emission limit or requirement on sources. These exemptions 
    from the opacity limits are inconsistent with the Act's requirement for 
    continuous compliance and attainment and maintenance of the NAAQS.
        EPA does not believe the requirement for the use of good air 
    pollution control practice for minimizing emissions during startups, 
    shutdowns, malfunctions, and significant PMO startups is an adequate 
    substitute for the opacity and SO2 limits. This provision in the 
    revisions to Regulation No. 1 is not adequate to ensure continuous 
    compliance as required by the Act.
        First, the revisions to Regulation No. 1 do not require a source to 
    show that the exceedance during startup, shutdown, or upset was 
    unavoidable. In fact, the revisions do not even require a source to 
    demonstrate that it has exercised good air pollution control practice 
    for minimizing emissions. Instead, section II.A.10.b and section 
    VI.B.4.a.(iv) provide that a determination of whether acceptable 
    operating and maintenance procedures are being used will be based on 
    information available to the Division. This appears to put no burden on 
    the source to justify an exceedance and does not appear calculated to 
    determine whether or not the exceedance could have been prevented 
    through careful planning and design or whether bypassing of the control 
    equipment was unavoidable to prevent loss of life, personal injury, or 
    severe property damage.
    
    [[Page 48134]]
    
        Second, the State's requirement that the source exercise good air 
    pollution control practice only appears to apply during startup, 
    shutdown, and malfunction. Clearly, a problem could arise during 
    startup, shutdown, and malfunction that could have been prevented by 
    careful planning, design, or implementation before the startup, 
    shutdown or malfunction. Also, the Bennett memoranda describe good air 
    pollution control practice for minimizing emissions as only one 
    criterion to examine in evaluating exceedances, and indicate that good 
    air pollution control practice for minimizing emissions should be 
    exercised to the ``maximum extent practicable,'' not just to the 
    ``extent practicable'' as the State provides.
        Furthermore, according to the AQCC's Statement of Basis for this 
    Regulation No. 1 revision, the exceedance percentage time allowance was 
    adopted to provide more certainty for the State and for sources in 
    enforcing the good air pollution control practice standard. Thus, the 
    Statement of Basis and the language of the regulation itself 
    (``exceedance percentage time allowance'') strongly imply that excess 
    emissions during startup, shutdown, and upset will only be considered 
    to be violations if the exceedance percentage time allowance is 
    exceeded (although the Statement of Basis also states that the State is 
    not precluded from taking enforcement action when the exceedance 
    percentage time allowance has not been exceeded).
        The State's rationale, in part, for revising the existing opacity 
    and SO2 provisions in Regulation No. 1 during periods of startup, 
    shutdown, and upset appears to have been to make the revised Regulation 
    No. 1 more consistent with the requirements in EPA's New Source 
    Performance Standards (NSPS) regarding startup, shutdown, and 
    malfunction (see 40 CFR part 60, subparts D and Da). However, emission 
    limitations and other control requirements of the NSPS were not 
    designed to ensure compliance with the NAAQS or to meet other SIP 
    requirements. Rather, the NSPS were designed to reflect best 
    demonstrated technology (taking into account costs) for the affected 
    sources. Further, because NSPS are based on the best system of emission 
    reduction which ``the Administrator determines has been adequately 
    demonstrated,'' EPA generally views the NSPS as the ``floor'' in 
    determining the emissions control technology that is feasible for a 
    source. Thus, the NSPS are intended to complement the SIP program, but 
    do not necessarily satisfy the requirements of section 110(a)(1) of the 
    Act, which requires control measures to provide for attainment and 
    maintenance of the NAAQS, or of other sections of the Act related to 
    SIP content.
        In summary, EPA believes the revisions to Regulation No. 1 are not 
    consistent with the Act because the revisions allow less than 
    continuous compliance with SIP emission limits that are designed to 
    attain and maintain the NAAQS without requiring sources to demonstrate 
    that excess emissions could not have been prevented or avoided. The 
    revisions to Regulation No. 1 significantly reduce the incentive for 
    continuous compliance by sources.
    6. EPA Invites Comment on Whether the SIP Revision Conflicts With EPA's 
    Any Credible Evidence Rule
        On February 24, 1997, EPA promulgated changes to Federal 
    Regulations to clarify that any credible evidence can be used to 
    demonstrate compliance or noncompliance with emission standards (see 62 
    FR 8314-8328). In that rulemaking, EPA revised the SIP requirements in 
    40 CFR 51.212 to state that the SIP ``must not preclude the use, 
    including the exclusive use, of any credible evidence or information 
    relevant to whether a source would have been in compliance with 
    applicable requirements if the appropriate performance or compliance 
    test or procedure had been performed.''
        As discussed above, section II.A.1. of Regulation No. 1 states that 
    visible emissions shall be measured by EPA Method 9 (40 CFR part 60, 
    appendix A) ``in all subsections of section II.A and B of this 
    regulation, unless otherwise specified.'' It is EPA's belief that this 
    language does not preclude the use of other credible evidence or 
    information to determine compliance with the opacity limits contained 
    in Regulation No. 1, or to determine whether a source has exceeded the 
    exceedance allowance specified in section II.A.10. of Regulation No. 1.
        Recently, the United States District Court for the District of 
    Colorado held that the language of Regulation No. 1 does not preclude 
    the use of other credible evidence to show opacity violations, at least 
    in citizens suits. See Sierra Club v. Tri-State Generation and 
    Transmission Association, Inc., et al., Order and Memorandum of 
    Decision, Civil Action No. 96 N 2368, March 8, 1999, at 19, 20. 
    However, it is not clear from the Court's opinion whether the Court was 
    examining the language of the Regulation No. 1 revision or the 
    Federally-approved version of Regulation No. 1. The revision to 
    Regulation No. 1 adds the language ``unless otherwise specified'' to 
    the end of the language that specifies Method 9 for measuring opacity. 
    Also, it is not clear whether the Court would reach the same conclusion 
    in an enforcement action brought by EPA or the State.
        Thus, EPA invites comment on whether the language of section 
    II.A.1. of Regulation No. 1 is consistent with the requirements of 40 
    CFR 51.212(c), and whether failure to comport with EPA's any credible 
    evidence rule should be an additional basis for disapproving the 
    revisions to Regulation No. 1.
        For the reasons discussed above, EPA is proposing to disapprove 
    Colorado's May 27, 1998 SIP submittal of revisions to Regulation No. 1. 
    EPA is soliciting public comments on the issues discussed in this 
    document or on other relevant matters. These comments will be 
    considered before taking final action. Interested parties may 
    participate in the Federal rulemaking procedure by submitting written 
    comments to the EPA Regional office listed in the Addresses section of 
    this document.
    
    III. Proposed Action
    
        EPA is proposing to disapprove the revision to the Colorado SIP 
    pertaining to the opacity and SO2 provisions in Regulation No. 1, which 
    was submitted by the Governor of Colorado on May 27, 1998. The effect 
    of this action, once final, will be that the pre-existing version of 
    Regulation No. 1 will remain in effect as part of the Federally 
    enforceable SIP and will continue to apply to opacity and SO2 emissions 
    from coal-fired electric utility boilers.
    
    IV. Administrative Requirements
    
    A. Executive Order 12866
    
        The Office of Management and Budget (OMB) has exempted this 
    proposed regulatory action from Executive Order 12866, entitled 
    ``Regulatory Planning and Review.''
    
    B. Executive Order 12875
    
        Under Executive Order 12875, EPA may not issue a regulation that is 
    not required by statute and that creates a mandate upon a state, local, 
    or tribal government, unless the Federal government provides the funds 
    necessary to pay the direct compliance costs incurred by those 
    governments. If the mandate is unfunded, EPA must provide to the Office 
    of Management and Budget a description of the extent of EPA's prior 
    consultation with representatives of affected state, local, and tribal 
    governments, the nature of their concerns, copies of written 
    communications from the governments, and a statement supporting the 
    need to issue the regulation.
    
    [[Page 48135]]
    
        In addition, Executive Order 12875 requires EPA to develop an 
    effective process permitting elected officials and other 
    representatives of state, local, and tribal governments ``to provide 
    meaningful and timely input in the development of regulatory proposals 
    containing significant unfunded mandates.'' Today's proposed rule would 
    not create a mandate on State, local or tribal governments. The rule 
    would not impose any enforceable duties on these entities. Accordingly, 
    the requirements of section 1(a) of Executive Order 12875 do not apply 
    to this rule.
    
    C. Executive Order 13045
    
        Executive Order 13045, Protection of Children from Environmental 
    Health Risks and Safety Risks (62 FR 19885, April 23, 1997), applies to 
    any rule that: (1) is determined to be ``economically significant'' as 
    defined under Executive Order 12866, and (2) concerns an environmental 
    health or safety risk that EPA has reason to believe may have a 
    disproportionate effect on children. If the regulatory action meets 
    both criteria, the Agency must evaluate the environmental health or 
    safety effects of the planned rule on children, and explain why the 
    planned regulation is preferable to other potentially effective and 
    reasonably feasible alternatives considered by the Agency.
        This proposed rule is not subject to Executive Order 13045 because 
    it does not involve decisions intended to mitigate environmental health 
    or safety risks.
    
    D. Executive Order 13084
    
        Under Executive Order 13084, EPA may not issue a regulation that is 
    not required by statute, that significantly affects or uniquely affects 
    the communities of Indian tribal governments, and that imposes 
    substantial direct compliance costs on those communities, unless the 
    Federal government provides the funds necessary to pay the direct 
    compliance costs incurred by the tribal governments. If the mandate is 
    unfunded, EPA must provide to the Office of Management and Budget, in a 
    separately identified section of the preamble to the rule, a 
    description of the extent of EPA's prior consultation with 
    representatives of affected tribal governments, a summary of the nature 
    of their concerns, and a statement supporting the need to issue the 
    regulation.
        In addition, Executive Order 13084 requires EPA to develop an 
    effective process permitting elected and other representatives of 
    Indian tribal governments ``to provide meaningful and timely input in 
    the development of regulatory policies on matters that significantly or 
    uniquely affect their communities.'' Today's proposed rule would not 
    significantly or uniquely affect the communities of Indian tribal 
    governments. EPA is proposing disapproval of a State rule revision, 
    which will have no impact on the communities of Indian tribal 
    governments. Accordingly, the requirements of section 3(b) of Executive 
    Order 13084 do not apply to this rule.
    
    E. Regulatory Flexibility Act
    
        The Regulatory Flexibility Act (RFA) generally requires an agency 
    to conduct a regulatory flexibility analysis of any rule subject to 
    notice and comment rulemaking requirements unless the agency certifies 
    that the rule will not have a significant economic impact on a 
    substantial number of small entities. Small entities include small 
    businesses, small not-for-profit enterprises, and small governmental 
    jurisdictions. This proposed rule would not have a significant impact 
    on a substantial number of small entities because EPA's proposed 
    disapproval of the State request under section 110 and subchapter I, 
    part D of the Clean Air Act, would not affect any existing requirements 
    applicable to small entities. Any pre-existing Federal requirements 
    would remain in place after this disapproval. Federal disapproval of 
    the State submittal would not affect State-enforceability. Moreover, 
    EPA's disapproval of the submittal would not impose any new Federal 
    requirements. Therefore, I certify that this action will not have a 
    significant economic impact on a substantial number of small entities.
    
    F. Unfunded Mandates
    
        Under section 202 of the Unfunded Mandates Reform Act of 1995 
    (``Unfunded Mandates Act''), signed into law on March 22, 1995, EPA 
    must prepare a budgetary impact statement to accompany any proposed or 
    final rule that includes a Federal mandate that may result in estimated 
    costs to State, local, or tribal governments in the aggregate; or to 
    the private sector, of $100 million or more. Under section 205, EPA 
    must select the most cost-effective and least burdensome alternative 
    that achieves the objectives of the rule and is consistent with 
    statutory requirements. Section 203 requires EPA to establish a plan 
    for informing and advising any small governments that may be 
    significantly or uniquely impacted by the rule.
        EPA has determined that the disapproval action being proposed does 
    not include a Federal mandate that may result in estimated costs of 
    $100 million or more to either State, local, or tribal governments in 
    the aggregate, or to the private sector. The proposed disapproval would 
    not change existing requirements and would include no Federal mandate. 
    If EPA were to disapprove the State's SIP submittal, pre-existing 
    requirements would remain in place and State enforceability of the 
    submittal would be unaffected. The action would impose no new 
    requirements. Accordingly, no additional costs to State, local, or 
    tribal governments, or to the private sector, would result from this 
    proposed action.
    
    G. National Technology Transfer and Advancement Act
    
        Section 12 of the National Technology Transfer and Advancement Act 
    (NTTAA) of 1995 requires Federal agencies to evaluate existing 
    technical standards when developing a new regulation. To comply with 
    NTTAA, EPA must consider and use ``voluntary consensus standards'' 
    (VCS) if available and applicable when developing programs and policies 
    unless doing so would be inconsistent with applicable law or otherwise 
    impractical.
        The EPA believes that VCS are inapplicable to this proposed action. 
    Today's proposed action does not require the public to perform 
    activities conducive to the use of VCS.
    
    List of Subjects in 40 CFR Part 52
    
        Environmental protection, Air pollution control, Incorporation by 
    reference, Intergovernmental relations, Particulate matter, Reporting 
    and recordkeeping requirements, and Sulfur oxides.
    
        Dated: August 19, 1999.
    Jack W. McGraw,
    Acting Regional Administrator, Region VIII.
    [FR Doc. 99-22937 Filed 9-1-99; 8:45 am]
    BILLING CODE 6560-50-P
    
    
    

Document Information

Published:
09/02/1999
Department:
Environmental Protection Agency
Entry Type:
Proposed Rule
Action:
Proposed rule.
Document Number:
99-22937
Dates:
Written comments must be received on or before October 4, 1999.2
Pages:
48127-48135 (9 pages)
Docket Numbers:
CO-001-0031, FRL-6432-7
PDF File:
99-22937.pdf
CFR: (1)
40 CFR 52