98-245. Revised Draft National Pollutant Discharge Elimination System (NPDES) General Permits for the Eastern Portion of Outer Continental Shelf (OCS) of the Gulf of Mexico (GMG280000)  

  • [Federal Register Volume 63, Number 4 (Wednesday, January 7, 1998)]
    [Notices]
    [Pages 846-877]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 98-245]
    
    
    -----------------------------------------------------------------------
    
    ENVIRONMENTAL PROTECTION AGENCY
    
    [FRL-5947-1]
    
    
    Revised Draft National Pollutant Discharge Elimination System 
    (NPDES) General Permits for the Eastern Portion of Outer Continental 
    Shelf (OCS) of the Gulf of Mexico (GMG280000)
    
    AGENCY: Environmental Protection Agency.
    
    ACTION: Notice of Revised Draft (NPDES) General Permit Reissuance, 
    Notice to States of Mississippi, Alabama and Florida for Consistency 
    Review with approved Coastal Management Programs.
    
    -----------------------------------------------------------------------
    
    SUMMARY: The Regional Administrator (RA) of EPA Region 4 (the 
    ``Region'') is today proposing to revise in part Draft National 
    Pollutant Discharge Elimination System (NPDES) general permits for the 
    Outer Continental Shelf (OCS) of the Gulf of Mexico (General Permit No. 
    GMG280000), published at 61 FR 64876 on December 9, 1996 for discharges 
    in the Offshore Subcategory of the Oil and Gas Extraction Point Source 
    Category (40 CFR part 435, subpart A). The existing permit, jointly 
    issued by Regions 4 and 6 and published at 51 FR 24897 on July 9, 1986, 
    authorizes discharges from exploration, development, and production 
    facilities located in and discharging to all Federal waters of the Gulf 
    of Mexico seaward of the outer boundary of the territorial seas. Region 
    6 issued a final permit (General Permit No. GMG290000) for the Western 
    portion of the OCS of the Gulf of Mexico, published at 57 FR 54642 on 
    November 19, 1992 for facilities in Federal waters seaward of Louisiana 
    and Texas Waters. Today's version extends permit coverage to the 
    Central Planning Area, except specified areas of the Central Planning 
    Area which are designated as Areas of Biological Concern. Today's 
    proposed revised draft NPDES permits cover existing and new source 
    facilities in the Eastern Planning Area (Alternative B of the 
    Environmental Impact Statement (EIS)) with operations on Federal leases 
    occurring in water depths seaward of 200 meters, occurring offshore the 
    coasts of Florida and Alabama, and existing and new source facilities 
    in the Central Planning Area (Alternative A of the EIS), with 
    operations located in and discharging pollutants to federal waters in 
    lease blocks located seaward of the outer boundary of the territorial 
    seas offshore Mississippi and Alabama. The western boundary of the 
    coverage area is demarcated by Mobile and Viosca Knoll leases located 
    seaward of the outer boundary of the territorial seas from the coasts 
    of Mississippi and Alabama in the Central Planning Area; except 
    specific areas in the Central Planning Area which may be designated by 
    EPA as Areas of Biological Concern (See Fact Sheet and Draft 
    Environmental Impact Statement). The eastern boundary of the coverage 
    area is demarcated by the Vernon Basin leases north of the 26 deg. 
    parallel and in water depths seaward of 200 meters.
        All permittees holding leases on which a discharge has taken place 
    within 2 years of the effective dates of the new general permits 
    (operating facilities) in these areas must file a written notice of 
    intent to be covered by either the new general permit for existing 
    sources or the new general permit for new sources within 60 days after 
    publication of the final determination on this action. Non-operational 
    leases, i.e., those on which no discharges have taken place in the 2 
    years prior to the effective date of the new general permits, are not 
    eligible for coverage under either general permit, and their coverage 
    under the old general permit will terminate on the effective date of 
    the new general permits. No NOI's will be accepted on non-operational 
    or newly acquired leases until such time as an exploration plan or 
    development production plan has been prepared for submission to EPA. 
    The notice of intent must contain the information set forth in 40 CFR 
    122.28(b)(2)(ii) and Section A.4 of the NPDES permit. In accordance 
    with Oil and Gas Extraction Point Source Category; Offshore Subcategory 
    Effluent Guidelines and New Source Performance Standards published at 
    58 FR 12454 on March 4, 1993, EPA Region 4 is making an Environmental 
    Impact Statement (EIS) available concurrently with the general permits 
    for review during the public comment period that addresses potential 
    impacts from facilities that may be defined as new sources in the 
    context of a comprehensive offshore permitting strategy. As set forth 
    in Section 2.4.2 of the EIS and information received, the Regional 
    Administrator has determined that the area in the Eastern Planning Area 
    shoreward of the 200 meter depth and certain designated areas in the 
    Central Planning Area includes extensive live bottom and other valuable 
    marine habitats and includes areas of biological concern, which should 
    be subject to more stringent review based on the ocean discharge 
    criteria under Section 403 of the Clean Water Act (CWA) and findings of 
    the EIS. Accordingly, individual permits will be issued for operating 
    facilities on lease blocks traversed by and shoreward of the 200 meter 
    water depth in the Eastern Planning Area and certain designated areas 
    of biological concern in the Central Planning Area. Owners or operators 
    of those leases will be notified in writing that an individual permit 
    is required. A brief statement of the reasons for this decision will be 
    provided, together with an application form and a deadline for filing 
    the application. If a timely application is received, general permit 
    coverage will continue and shall automatically terminate on the date 
    final action is taken on the individual NPDES permit application, in 
    accordance with 40 CFR 122.28(b)(3)(ii). No application will be 
    accepted for non-operational leases until such time as an exploration 
    plan or development production plan has been prepared for submission to 
    EPA. Owners of non-operational leases and operators who neither file a 
    notice of intent nor an individual permit application will lose 
    coverage under the old general permit on the effective date of the new 
    general permits.
        As proposed, these NPDES general permits include BPT, BCT, and BAT
    
    [[Page 847]]
    
    limitations for existing sources and NSPS limitations for new sources 
    as recently promulgated in the effluent guidelines for the offshore 
    subcategory at 58 FR 12454 (March 4, 1993). The permits also address a 
    decision of the Ninth Circuit Court of Appeals by establishing limits 
    on cadmium and mercury and by removing references to Alternative 
    Toxicity Requests. In addition, the permits delete references to the 
    Diesel Pill Monitoring Program, incorporate a new limitation on garbage 
    discharges consistent with the regulations of the U.S. Coast Guard, 
    clarify the applicability of some of the permit's effluent limitations 
    and reporting requirements, establish aquatic toxicity limitations for 
    produced water, and include a reopener clause.
    
    ADDRESSES: Persons wishing to comment upon or object to any aspects of 
    this permit reissuance or wishing to request a public hearing, are 
    invited to submit same in writing within forty-five (45) days of this 
    notice to the Office of Environmental Assessment, United States 
    Environmental Protection Agency, Region 4, Atlanta Federal Center, 61 
    Forsyth Street, S.W., Atlanta, GA 30303-3104, Attention: Ms. Lena 
    Scott.
    
    DATES: Comments on this proposed action must be received by February 
    23, 1998.
    
    FOR FURTHER INFORMATION: Contact Mr. Roosevelt Childress, Chief, 
    Surface Water Permits Section, telephone (404) 562-9279, or Mr. Larry 
    Cole, Environmental Engineer, telephone (404) 562-9307 or the following 
    address: Water Management Division, Surface Water Permits Section, U.S. 
    EPA, Region 4, Atlanta Federal Center, 61 Forsyth Street, S.W., 
    Atlanta, GA 30303-3104.
    
    SUPPLEMENTAL INFORMATION:
    
    Procedures for Reaching a Final Permit Decision
    
        Pursuant to 40 CFR 124.13, any person who believes any condition of 
    the permit is inappropriate must raise all reasonably ascertainable 
    issues and submit all reasonably available arguments in full, 
    supporting their position, by the close of the comment period. All 
    comments on the proposed revised NPDES general permits and the EIS 
    received within the 45-day period will be considered in the formulation 
    of final determinations regarding the permit reissuance. EPA will 
    consider all written comments submitted pursuant to this notice of 
    revised draft general permit, as well as all written comments submitted 
    pursuant to the December 9, 1996 draft general permit and all comments 
    received during the four (4) public hearings for the draft general 
    permit.
        After consideration of all written comments and the requirements 
    and policies in the Act and appropriate regulations, the EPA Regional 
    Administrator will make determinations regarding the permit reissuance. 
    If the determinations are substantially unchanged from those announced 
    by this notice, the Administrator will so notify all persons submitting 
    written comments. If the determinations are substantially changed, the 
    Administrator will issue a public notice indicating the revised 
    determinations.
        A formal hearing is available to challenge any NPDES permit issued 
    according to the regulations at 40 CFR 124.15 except for a general 
    permit as cited at 40 CFR 124.71. Persons affected by a general permit 
    may not challenge the conditions of a general permit as a right in 
    further Agency proceedings. They may instead either challenge the 
    general permit in court, or apply for an individual permit as specified 
    at 40 CFR 122.21 as authorized at 40 CFR 122.28, and then request a 
    formal hearing on the issuance or denial of an individual permit. 
    Additional information regarding these procedures is available by 
    contacting Mr. David M. Moore, Office of Regional Counsel at (404) 562-
    9547.
    
    Procedures for Obtaining General Permit Coverage
    
        Notice of Intent (NOI) requirements for obtaining coverage for 
    operating facilities under both permits are stated in Part I Section 
    A.4 of the general permit. Coverage under the new general permit is 
    effective upon receipt of notification of inclusion from the Director 
    of the Water Management Division. EPA will act on the NOI within a 
    reasonable period of time.
    
    Exclusion of Non-Operational Leases
    
        These permits do not apply to non-operational leases, i.e., those 
    on which no discharge has taken place in the 2 years prior to the 
    effective dates of the new general permit. EPA will not accept NOI's 
    for such leases, and these general permits will not cover such leases. 
    Non-operational leases will lose coverage under the old general permit 
    on the effective date of the new general permits. No subsequent 
    exploration, development or production activities may take place on 
    these leases until and unless the lessee has obtained coverage under 
    one of the new general permits or an individual permit. EPA will not 
    accept NOI's or individual permit applications for non-operational or 
    new acquired leases until such time as an exploration plan or 
    development production plan has been prepared for submission to EPA.
        The new permitting requirements for leases covered under the old 
    general permits are summarized in Table 1.
    
                  Table 1.--New Permitting Requirements for Leases Covered Under the Old General Permit             
    ----------------------------------------------------------------------------------------------------------------
                                                               Coverage        Date old general     Type of permit  
             Lease location            Discharge status      requirements       permit expires         coverage     
    ----------------------------------------------------------------------------------------------------------------
    Central Planning Area & Outside   (1) Operational...  File an NOI within  Date EPA Notifies   New General       
     200 meter Isobath in Eastern                          60 days of          Lessee of New       Permit, except   
     Planning Area.                                        effective date of   Coverage Decision.  near an Area of  
                                                           new general                             Biological       
                                                           permit.                                 Concern.         
                                      (2) Leases With     File NOI At Time    Effective Date of   New General       
                                       Imminent Projects.  Exploration Plan    New General         Permit, except   
                                                           or Development      Permit.             near an Area of  
                                                           Production Plan                         Biological       
                                                           Exists.                                 Concern.         
                                      (3) Non-            No NOI will be      Effective Date of   None.             
                                       Operational.        accepted;           New General                          
                                                           Ineligible for      Permit.                              
                                                           General Permit                                           
                                                           Coverage.                                                
    
    [[Page 848]]
    
                                                                                                                    
    Inside 200 meter Isobath in       (1) Operational...  File an individual  Date EPA notifies   Individual Permit.
     Eastern Planning Area & certain                       permit              lessee of                            
     designated areas in the Central                       application         Individual permit                    
     Planning Area.                                        within 120 days     decision.                            
                                                           of effective date                                        
                                                           of new general                                           
                                                           permit.                                                  
                                      (2) Lessees with    File an Individual  Effective date of   Individual Permit.
                                       Imminent Projects.  Permit              New General                          
                                                           Application when    Permit.                              
                                                           Lessee has                                               
                                                           Exploration Plan                                         
                                                           or Development                                           
                                                           Production Plan.                                         
                                       (3) Non-           Ineligible For      Effective Date of   None.             
                                       Operational.        General Permit      New General                          
                                                           Coverage.           Permit.                              
    ----------------------------------------------------------------------------------------------------------------
    
    State Water Quality Certification
    
        Because state waters are not included in the area covered by the 
    OCS general permit, its effluent limitations and monitoring 
    requirements are not subject to state water quality certification under 
    CWA Section 401.
    
    State Consistency Determination
    
        This revised package will also serve as Region 4's requirement 
    under the Coastal Zone Management Act (CZMA) to provide all necessary 
    information for the States of Mississippi, Alabama and Florida to 
    review this action for consistency with their approved Coastal 
    Management Programs. A copy of the consistency determination on the 
    proposed activities will be sent to each affected State, along with 
    draft copies of the draft NPDES general permit, Fact Sheet, preliminary 
    Ocean Discharge Criteria Evaluation, and final Environmental Impact 
    Statement. Other relevant information is available upon request from 
    each State for their review. Comments regarding State Consistency are 
    invited in writing to the Office of Public Affairs, United States 
    Environmental Protection Agency, Region 4, Atlanta Federal Center, 61 
    Forsyth Street, S.W., Atlanta, GA 30303-3104, Attention: Ms. Lena 
    Scott.
    
    Previous Public Hearings
    
        Four (4) previous public hearings were held on the general permit 
    in January and February of 1997. The hearings were held on January 28, 
    1997 in Gulfport, Mississippi, January 29, 1997 in Gulf Shores, 
    Alabama, January 30, 1997 in Pensacola, Florida and February 4, 1997 in 
    St. Petersburg, Florida. Comments received in these hearings will be 
    used in the final determinations regarding permit reissuance.
    
    Administrative Record
    
        The proposed revised NPDES general permits, fact sheet, preliminary 
    403(c) determination, EIS and other relevant documents are on file and 
    may be inspected any time between 8:15 a.m. and 4:30 p.m., Monday 
    through Friday at the address shown below. Copies of the draft NPDES 
    general permits, fact sheet, preliminary 403(c) determination, EIS and 
    other relevant documents may be obtained by writing the U.S. EPA, 
    Region 4, Atlanta Federal Center, 61 Forsyth Street, S.W., Atlanta, 
    Georgia 30303-3104, Attention: Ms. Lena Scott, or calling (404) 562-
    9607.
    Robert F. McGhee,
    Director, Water Management Division.
    
    Table of Contents
    
    I. Background Information On General Permits and Proposed Individual 
    Permits
        A. Previous OCS General Permit
        B. Discussion of three (3) Alternatives Examined by EIS
        C. Conclusions from EIS and more information on Biological 
    Communities
        D. Proposed Eastern Gulf of Mexico General Permits
    
        (1) New Sources
        (2) Existing Sources
        (3) Application Procedures
    
        E. Proposed Individual Permits
        F. Basis for Extending General Permit Coverage into the Central 
    Planning Area
        G. Description of Designated Areas of Biological Concern in the 
    Central Planning Area
        H. Oil & Gas Activities Occurring in the Eastern Gulf of Mexico
    II. Description of activity and facilities which are subject of 
    draft permits
    III. Nature of Discharges from Oil and Gas Operations and Effluent 
    Limits
    IV. Statutory Basis for Permit Conditions
        A. Technology Bases
    
        1. BPT Effluent Limitations for Existing Source General Permit
        2. BAT and BCT Effluent Limitations and New Source Performance 
    Standards (NSPS)
        3. Previous NPDES General Permit Limitations
    
        B. Ocean Discharge Criteria
        C. Section 308 of the Clean Water Act
    V. Summary of New or Changed Permit Limitations and Conditions
        A. Alternative Toxicity Requests
        B. Cadmium and Mercury in Barite
        C. New Sources
        D. Free Oil
        E. Produced Sand
        F. Produced Water
        G. Diesel Oil Prohibition
        H. Water Quality-Based Effluent Limitations and Conditions
        I. Aquatic Toxicity Limits & Testing Requirements for Produced 
    Water
        J. Discharge Prohibition in Vicinity of Areas of Biological 
    Concern
        K. Rubbish, Trash, and Other Refuse (MARPOL)
        L. 24-hr Reporting Requirement
        M. Reopener Clause
        N. Clarifications
    VI. Specific Permit Conditions
        A. Determination of Discharge Conditions
        B. Area and Depth-Related Requirements
        C. Section 403(c) Requirements
    VII. Other Legal Requirements
        A. National Environmental Protection Act
        B. Oil Spill Requirements
        C. Ocean Discharge Criteria Evaluation
        D. Coastal Zone Management Act
        E. Marine Protection, Research, and Sanctuaries Act
        F. Executive Order 12291
        G. Paperwork Reduction Act
        H. Regulatory Flexibility Act
        I. References
    
    Fact Sheet
    
    I. Background Information Concerning General Permits and Proposed 
    Individual Permits
    
        Section 301(a) of the Clean Water Act (the ``Act'') provides that 
    the discharge of pollutants is unlawful except in accordance with the 
    terms of an NPDES permit. The Regional Administrator has determined, on 
    the basis of the EIS and information received, that oil and gas 
    facilities seaward of the 200 meter water depth in certain parts of the 
    Eastern Planning Area and seaward of the outer boundary of the 
    territorial seas in the Central Planning Areas described in the 
    proposed NPDES general permits are more appropriately controlled by 
    general permits rather than individual permits, 40 CFR 122.28(c). This
    
    [[Page 849]]
    
    determination covers both existing sources and new sources. 
    Accordingly, two (2) NPDES general permits are being proposed: one 
    covering existing sources and the second covering new sources. This 
    decision is based on 40 CFR 122.28, 40 CFR 125 (Subpart M--Ocean 
    Discharge Criteria), Environmental Impact Statement and the Agency's 
    previous decisions in other areas of the Gulf of Mexico's Outer 
    Continental Shelf (OCS). As in the case of individual permits, 
    violation of any condition of a general permit constitutes a violation 
    of the Act that is enforceable under section 309 of the Act.
        In accordance with 40 CFR 122.28(a)(4)(iii), any owner or operator 
    authorized by a general permit may request to be excluded from the 
    coverage of the general permit by applying for an individual permit. 
    The owner or operator shall submit an application under 40 CFR 122.21, 
    with reasons supporting the request, to the Director, Water Management 
    Division, Surface Water Permits Section, U.S. EPA, Atlanta Federal 
    Center, 61 Forsyth Street, S.W., Atlanta, GA 30303-3104.
    
    A. Previous OCS NPDES General Permit
    
        The Regional Administrator for EPA Region 4 is today proposing to 
    reissue in part the National Pollutant Discharge Elimination System 
    (NPDES) general permit for the Outer Continental Shelf of the Gulf of 
    Mexico (General Permit No. GMG280000) under Region 4 jurisdiction. This 
    previous permit, published at 51 FR 24897 (July 9, 1986), issued 
    jointly for the Eastern and Western Gulf of Mexico by Regions 4 and 6, 
    expired on July 1, 1991. Region 6 reissued a final existing permit for 
    the Western Portion of the Outer Continental Shelf (General Permit No. 
    GMG290000), published at 57 FR 54642 (November 19, 1992) with a 
    modification published at 58 FR 63964 (December 3, 1993). Region 4, 
    continued coverage under the previous OCS general permit to permittees 
    that requested to be covered before the previous general permit expired 
    on July 1, 1991. Region 4 proposed draft NPDES general permits for the 
    Eastern Gulf of Mexico at 61 FR 64876 on December 9, 1996, regulating 
    existing source and new source oil and gas OCS discharges. Today's 
    proposed Eastern Gulf of Mexico OCS revised general permits regulate 
    existing source and new source OCS discharges throughout the Gulf of 
    Mexico for offshore areas under the jurisdiction of Region 4.
    
    B. Discussion of Three (3) Alternatives Examined by the Environmental 
    Impact Statement (EIS)
    
        Since the promulgation of effluent guidelines and standards of 
    performance for new sources at 58 FR 12454 (March 4, 1993), EPA 
    regulations in 40 CFR 122.29(c) require that the issuance of an NPDES 
    permit to a new source be subject to environmental review provisions of 
    the National Environmental Policy Act (NEPA) as defined in 40 CFR Part 
    6, Subpart F. A Draft Environmental Impact Statement (EIS) has been 
    prepared by EPA. The EIS examined three (3) alternatives for permitting 
    exploration development and production phases of oil and gas 
    activities. Alternative A: Issuing two general permits, one for 
    existing sources and the other for new sources, that would cover the 
    entire EPA Region 4 jurisdictional area except areas under moratorium. 
    Alternative B: Issuing two general permits, one for existing sources 
    and the other for new sources, that would only apply to locations 
    seaward of the 200 meter isobath, and would exclude areas under 
    moratorium. Alternative C: EPA would not issue NPDES general permits 
    covering either existing sources or new sources and would handle all 
    future oil and gas activities occurring in EPA Region 4 jurisdictional 
    area by individual permits. Chapter 2 of the EIS should be reviewed for 
    a discussion of these three (3) alternatives. Chapter 3 of the EIS 
    discusses the affected environment and potential environmental 
    consequences of the three (3) alternatives. EPA, Region 4, plans to 
    issue shortly the final EIS.
    
    C. Conclusions From EIS and Information Received on Biological 
    Communities in the Coastal Shelf and Shelf-Break Zone
    
        The EIS reviews available data and studies on discharges from oil 
    and gas facilities and the potential for these discharges resulting in 
    impacts to benthic communities of short and long term duration. The EIS 
    concludes that because of the abundance and sensitivity of the 
    biological resources present from 200 meters of depth and shallower and 
    potential secondary impacts, individual permits for these areas which 
    incorporate permit stipulations on a case-by-case review would be more 
    protective of the numerous biological communities present in the 200 
    meter water depths or shallower, and help ensure compliance with 
    Section 403(c) of the CWA. Because areas of biological concern are more 
    abundant in water depths of 200 meters or shallower and potential for 
    environmental impacts is greater, Region 4 chose alternative B as its 
    preferred alternative as the permitting strategy for the Eastern Gulf 
    of Mexico. This alternative would have required individual permits to 
    be issued for activity occurring in water depths 200 meters of 
    shallower, off the coasts of Mississippi, Alabama and Florida. Based on 
    more complete information, Region 4 is adopting alternative A for the 
    Eastern Gulf of Mexico's Central Planning Area, which provides for 
    general permit coverage within the Central Planning Area, except in 
    certain designated areas specifically excluded from NPDES general 
    permit coverage identified as areas of biological concern. This 
    approach allows for case-by-case review of impacts in waters 200 meters 
    of depth and shallower in the Eastern Planning Area where less 
    information is available for the assessment of impacts, and in areas of 
    biological concern identified within the Central Planning Area where 
    more complete information regarding environmental impacts are 
    available. This strategy requires current or proposed oil and gas 
    operations in the Eastern Planning Area shoreward of the 200 meter 
    water depth and in certain designated areas of the Central Planning 
    Area to seek individual existing source or new source permits, as 
    appropriate.
    
    D. Proposed Eastern Gulf of Mexico NPDES General Permits
    
        These proposed draft Eastern Gulf of Mexico NPDES general permits 
    authorize discharges from exploration, development, and production 
    facilities (existing sources or new sources) discharging to Federal 
    waters of the United States of the Gulf of Mexico. Region 4's coverage 
    area for these general permits includes all discharges occurring in 
    leases located seaward of the 200 meter water depth for offshore, 
    Alabama and Florida in the Eastern Planning Area and discharges 
    occurring seaward of the outer boundary of the territorial seas 
    offshore Alabama and Mississippi in the Central Planning Area, as 
    explained in Part I Section A(1) of the general permit. These permits 
    do not cover areas included under Congressional or Presidential 
    moratorium for oil and gas activities in Federal waters.
        40 CFR 122.29 requires that separate permits be issued for new 
    sources. Accordingly, two general permits will be issued for the area 
    seaward of the 200 meter depth in the Eastern Planning Area and seaward 
    of the outer boundary of the territorial seas in the Central Planning 
    Area: one for new sources, and the other for existing sources. These
    
    [[Page 850]]
    
    permits apply only to operating facilities; they do not apply to non-
    operational leases.
    (1) New Source General Permit
        The RA has determined, in accordance with 40 CFR 122.28(c), that 
    the new source general permit will apply to all new sources, as that 
    term is defined at 40 CFR 122.2 as ``any building, structure, facility, 
    or installation from which there is or may be a discharge of 
    pollutants, the construction of which is commenced:
        (a) After promulgation of standards of performance under section 
    306 of CWA which are applicable to such source, or
        (b) After proposal of standards of performance in accordance with 
    section 306 of CWA which are applicable to such sources, but only if 
    the standards are promulgated in accordance with section 306 within 120 
    days of their proposal.''
        If construction was commenced after March 4, 1993, the facility is 
    a new source. Because drilling rigs are moved from site to site for 
    several years and production platforms can be built on shore and 
    transported to an offshore site, the actual construction of the 
    equipment or facility can occur years before there is a discharge of 
    pollutants from that equipment or facility at a particular site. 
    Therefore, the definition of the ``construction'' of a new source must 
    be addressed. The regulations at 40 CFR 122.29(b)(4) state:
        ``(4) Construction of a new source as defined under 122.2 has 
    commenced if the owner or operator has:
        (i) Begun, or caused to begin as part of a continuous on-site 
    construction program:
        (A) Any placement, assembly, or installation of facilities or 
    equipment; or
        (B) Significant site preparation work including clearing, 
    excavation or removal of existing buildings, structures, or facilities 
    which is necessary for the placement, assembly, or installation of new 
    sources facilities or equipment; or
        (ii) Entered into a binding contractual obligation for the purchase 
    of facilities or equipment which are intended to be used in its 
    operation within a reasonable time. Options to purchase or contracts 
    which can be terminated or modified without substantial loss, and 
    contracts for feasibility engineering, and design studies do not 
    constitute a contractual obligation under the paragraph.''
        EPA defines ``significant site preparation work'' as ``the process 
    of clearing and preparing an area of the ocean floor for purposes of 
    constructing or placing a development or production facility on or over 
    the site'' (50 FR 34619). Therefore, development and production wells 
    are new sources unless the site was cleared and prepared for the 
    purposes of constructing or placing a development or production 
    facility over that site before the promulgation of the effluent 
    guideline for the offshore subcategory on March 4, 1993. Exploration 
    activities are not considered significant site preparation work; 
    therefore sites where exploration has occurred are not considered 
    existing sources.
        EPA regulations also define the term ``site'' at 40 CFR 122.2 as 
    ``the land or water area where any facility or activity is physically 
    located or conducted, including adjacent land used in connection with 
    the facility or activity.'' EPA interprets the term ``water area'' to 
    mean the ``specific geographical location where the exploration, 
    development, or production activity is conducted, including the water 
    column and ocean floor beneath activities.'' Thus, if a new platform is 
    built at or moved from a different location, it will be considered a 
    new source when placed at the new site where its oil and gas activities 
    take place. Even if the platform is placed adjacent to an existing 
    platform, the new platform will still be considered a ``new source'' 
    occupying a ``new water'' area, and therefore, a ``new site'' (50 CFR 
    34618).
    (2) Existing Source General Permit
        All other facilities must obtain coverage under the existing source 
    general permit. Existing sources are those facilities where significant 
    site preparation work has occurred, or development and production 
    activity has taken place, on or before March 4, 1993. These same 
    facilities, however, would become new sources if they moved to a new 
    water area to commence production or development activities. 
    Exploratory activities require existing source general permit coverage.
    (3) Application Procedures
        Permittees holding leases with operating facilities seaward of the 
    200 water meter depth in the Eastern Planning Area and seaward of the 
    outer boundary of the territorial seas in the Central Planning Area 
    (except designated areas of Biological Concern) will be required to 
    file a Notice of Intent, pursuant to 40 CFR 122.28(b)(2)(ii), to be 
    covered by either the new source general permit or the existing source 
    general permit, as applicable, within 60 days after publication of the 
    final determination on this action. Such notice fulfills the permit 
    application requirements under federal regulations. The permittee will 
    be covered under the appropriate new general permit (existing or new 
    source) upon receipt of notification of inclusion from the Director. A 
    discharger having coverage under the old general permit who fails to 
    timely submit such a notice is not authorized to discharge pursuant to 
    40 CFR 122.28(b)(2), and is no longer covered under the old general 
    permit.
    
    E. Proposed Individual Permits
    
        All lease blocks with operating facilities traversed by or 
    shoreward of the 200 meter isobath in the Eastern Planning Area and in 
    designated areas of biological concern in the Central Planning Area 
    (See Item G below for designated areas of biological concern and 
    Appendix B for map showing area) will be required to apply for and 
    obtain individual permits in order to discharge into U.S. waters. No 
    individual permits will be issued for non-operational leases until an 
    exploration plan or development production plan has been prepared for 
    submission to EPA. As with the general permits, there are two kinds of 
    individual permits that will be issued.
        The first is an individual new source permit. The application 
    requirements for new sources are set forth at 40 CFR 122.21(k) and (l). 
    Prior to issuance of such permits, the law requires that an 
    Environmental Impact Statement (EIS) or Environmental Assessment (EA) 
    be prepared. In order to allow EPA to conduct that review, the 
    applicant must submit information as set forth in 40 CFR 6.604(b).
    
    F. Basis for Extending General Permit Coverage Into the Central 
    Planning Area
    
        Region 4, after review of more complete data, proposes to extend 
    general permit coverage into the Central Planning Area. Based on 
    current activity levels in the Central Planning Area (CPA), the Region 
    believes the CPA has been extensively surveyed for the location of 
    drilling and production sites and have been documented. Available 
    scientific survey literature of the Mississippi-Alabama shelf notes the 
    general lack of firm bottom substrate for attachment of bottom life, 
    high water column turbidity in much of the east-central inner shelf, 
    and a trend of increased water clarity and light penetration eastward 
    (Vittor, 1985). The Area is not normally under the influence of the 
    sub-tropical Loop Current that elsewhere stabilizes water temperature 
    more suitable to increased epifaunal diversity. It has also been 
    documented that the bottom area offshore Mississippi-Alabama 
    experiences substantial deposition of
    
    [[Page 851]]
    
    fine particle sediments eminating from cover rivers (Rabalais and 
    Boesch, 1987) that would tend to cover previously exposed hard 
    substrate. Features that Region 4 is now defining as Areas of 
    Biological Concern are pronounced in terms of topography and are fairly 
    well discernable by survey. Brooks and Giammona found predominately 
    soft sediments punctuated in some areas with rock outcrops and 
    topographic (the pinnacle trend) high features. The Region has added a 
    condition to the NOI requirements for applicants seeking general permit 
    coverage to provide photodocumentation and geohazards surveys in order 
    to allow approval of specific project sites in the Central Planning 
    Area after this data is reviewed.
    
    G. Description of Designated Areas of Biological Concern in the Central 
    Planning Area
    
    A. Southwest Rocks
        Feature consists of two clusters of pitted shell and sandstone rock 
    outcrops measuring 23-30 feet across and 5-11 feet across, rising 3-5 
    feet above the bottom. Feature includes a gently sloping ridge with 3-5 
    feet of relief. The feature is in water depths of 66-72 feet, 
    approximately 10.5 miles south of Dauphin Island. Rocks bear epifaunal 
    encrustation mainly of barnacles, serpulid worms and bryozoans. 
    (Schroeder, 1988)
    B. Southeast Banks
        A rock rubble field consisting of irregularly shaped, pitted 
    sandstone slabs up to 2.5 x 2.3 x 0.7 feet in size. Rocks have 
    epifaunal encrustation. Feature includes two sites located in water 
    depths of 70 to 87 feet, 17 miles south of the Ft. Morgan peninsula. 
    (Schroeder, 1988)
    C. 17 Fathom Hole
        Feature is an uncharted, irregular bottom depression in 98-105 feet 
    of water. It is composed of an assortment of irregularly-shaped rock 
    rubble, shell and coarse sand. The feature is located approximately 23 
    miles south of the entrance to Mobile Bay. (Schroeder, 1988)
    D. Pinnacle Trend
        This feature occupies Viosca Knoll Lease Blocks 473-476, 521 and 
    522, 564-566, 609 and 610 within Region 4 jurisdiction. This is a 
    series of topographic irregularities with variable biotic coverage 
    along the Mississippi-Alabama shelf break, between the 40-80 meter 
    depth contours. The feature contains a variety of structure including 
    low-relief rocky structure to more dramatic pinnacle-shaped structures, 
    ridges, scarps and relict patch reefs. The structure provides 
    significant solid substrate for attachment by different invertebrate 
    organisms that vary in number and diversity. (MMS, 1997)
        The RA will then make and publish a determination as to whether the 
    facility seeking a permit is a new source.
        The second type of individual permit is for an existing source. 
    Applicants shall submit the information required by 40 CFR 122.21(f), 
    together with any additional information required to determine the 
    appropriate permit limits based on ocean discharge criteria under 
    Sec. 403 of the CWA.
        Permittees holding leases shoreward of the 200 meter depth in the 
    Eastern Planning Area and in designated areas of biological concern in 
    the Central Planning Area will be given individual notice of the 
    requirement to apply for an individual permit, a brief statement of the 
    reasons therefore, a copy of the application form, and a deadline for 
    filing the application. No applications will be accepted for non-
    operational or newly acquired leases until such time as an exploration 
    plan or development production plan has been prepared for submission to 
    EPA. All permittees with operational facilities, i.e., leases on which 
    a discharge has taken place within 2 years of the effective date of the 
    new general permits, who file a timely application will continue to be 
    covered under the old general permit until a final action has been 
    taken on the individual permit application.
    
    H. Oil and Gas Activities in the Eastern Gulf of Mexico
    
        Historically, activity in the Eastern Gulf of Mexico has been less 
    than that in areas west of Region's 4 jurisdiction. This was partly due 
    to the demand for natural gas and economics associated with drilling 
    costs necessary to reach the deep Norphlet and other producible 
    commercial formations. As the price and demand for natural gas 
    increases, along with the development of deep water drilling and 
    producing technology, exploration activities in this area will 
    continue. In 1991, an EPA Region 4 survey of the major oil companies 
    revealed that fifty (50) wells had been drilled in the eastern Gulf and 
    17 wells were producing. The producing wells were located either 
    offshore Alabama and Mississippi, with no producing wells located in 
    Federal waters offshore Florida. Additionally, the 1991 survey revealed 
    that there are only three facilities discharging produced water. These 
    facilities were located in the Mobile leasing area: one in Block 908 
    discharging approximately 2 barrels of produced water per day (BPD); 
    one in Block 990 discharging approximately 160 BPD; and one in Block 
    821 discharging approximately 240 BPD. A map of the area revealed that 
    these facilities are located in 15-20 meters of water. The survey 
    revealed that there were no current producing wells seaward of water 
    depths greater than 40 meters.
    
    II. Description of Activity and Facilities Which Are Subject of 
    Draft Permits
    
        The Oil and Gas Extraction Point Source Category (40 CFR 435--
    Subpart A) includes facilities engaged in field exploration, 
    development and well production and well treatment. Exploration 
    facilities are fixed or mobile structures engaged in the drilling of 
    wells to determine the nature of potential hydrocarbon reservoirs. A 
    development facility is any fixed or mobile structure engaged in the 
    drilling and completion of productive wells, which may occur prior to, 
    or simultaneously with production operations. Production Facilities are 
    fixed or mobile structures engaged in well completion or used for 
    active recovery of hydrocarbons from producing formations.
    
    III. Nature of Discharges From Oil and Gas Operations and Effluent 
    Limits
    
        The proposed general permits will authorize the following 
    discharges to occur in the previously delineated coverage area: 
    drilling mud; drill cutting; produced water; well treatment fluids; 
    workover fluids; completion fluids; deck drainage, sanitary wastes; 
    domestic wastes, desalinization unit discharges, blowout preventer 
    fluid; fire control system test water; non-contact cooling water; 
    uncontaminated ballast water; uncontaminated bilge water; excess cement 
    slurry; and mud, cuttings and cement at the seafloor. The proposed 
    permits will authorize discharges from facilities engaged in field 
    exploration, development and well production and well treatment, for 
    offshore operations for both existing and new sources for leases in the 
    Eastern Gulf of Mexico.
        The effluent guidelines include Best Available Technology 
    Economically Achievable (BAT) limitations for existing sources and New 
    Source Performance Standards (NSPS) that are based on the best 
    available demonstrated technology for new sources. New facilities have 
    the opportunity to install the best and most efficient production 
    processes and waste water treatment technologies. Therefore, Congress 
    directed EPA to consider the best demonstrated process
    
    [[Page 852]]
    
    changes, in-plant controls, and end-of-process control and treatment 
    technologies that reduce pollution to the maximum extent feasible for 
    implementation by new sources.
        Upon its issuance in 1986, the existing general permit was 
    judicially challenged by various parties in Natural Resources Defense 
    Council v. EPA, 863 F.2d 1420 (9th Cir. 1988). Although the Court 
    affirmed EPA's permit decisions on most of the issues litigated, the 
    Court (1) invalidated the provisions that allowed for case-by-case 
    variances from toxicity limitations under the permit's alternate 
    toxicity request provisions, and (2) held that EPA should have provided 
    additional consideration to requiring the use of ``clean'' barite in 
    drilling fluids. Today's proposal responds to that decision.
        In the reissuance of these NPDES general permits, EPA Region 4 is 
    responding to four legal or regulatory developments. The first legal 
    development is the decision of the Ninth Circuit Court on challenges to 
    the 1986 permit. All references to alternative toxicity limits are 
    eliminated from this permit and the use of clean barite is required for 
    drilling operations. The second regulatory development is the 
    promulgation of final BAT and NSPS guidelines for the offshore 
    subcategory (58 FR 12454). These NPDES general permits provide an 
    explanation of how the determination of new sources will be made and 
    incorporate the limitations and conditions set forth by the guidelines 
    for offshore exploration, development, and production waste streams. 
    The third and fourth regulatory developments are EPA's national policy 
    on water quality-based permit limitations (49 FR 9016) and the issuance 
    of pollution prevention regulations by the U.S. Coast Guard (33 CFR 
    151). The national policy is a strategy to control pollutants beyond 
    BAT in order to meet water quality standards by use of biological and 
    chemical methods to address toxic and nonconventional pollutants. The 
    U.S. Coast Guard regulations are incorporated into the permit to be 
    consistent with international regulations for the disposal of food and 
    incinerator wastes.
        Comments on these draft NPDES general permits need not be limited 
    to those changes listed above. EPA is specifically soliciting 
    information to further characterize present and anticipated activities 
    on the eastern Gulf of Mexico OCS. EPA Region 4 may revise any 
    provisions of the permit in response to public comments when it issues 
    the final permit.
    
    IV. Statutory Basis for Permit Conditions
    
        Sections 301(b), 304, 306, 307, 308, 401, 402, 403 and 501 of the 
    Clean Water Act (The Federal Water Pollution Control Act Amendments of 
    1972, as amended by the Clean Water Act of 1977 and the Water Quality 
    Act of 1987), 33 U.S.C. 1311, 1314(b), (c) and (e), 1316, 1317, 1318 
    and 1361; 86 Stat. 816, Pub. L. 92-500; 91 Stat. 1567, Pub. L. 95-217; 
    101 Stat. 7 Pub. L. 100-4 (``the Act'' or CWA''), and the U.S. Coast 
    Guard Regulations (33 CFR Part 151), provide the basis for the permit 
    conditions contained in both the existing and new source general 
    permits. The general requirements of these sections fall into three 
    categories, which are described in sections A-C below.
    
    4A. Technology Bases
    
    1. BPT Effluent Limitations
        The Act requires particular classes of industrial discharges to 
    meet effluent limitations established by EPA. EPA promulgated effluent 
    guidelines requiring Best Practicable Control Technology Currently 
    Available (BPT) for the Offshore and Coastal Subcategories of the Oil 
    and Gas Extraction Point Source Category (40 CFR Part 435, Subparts A 
    and D) on April 13, 1979 (44 FR 22069).
        BPT effluent limitations guidelines require ``no discharge of free 
    oil'' for discharges of deck drainage, drilling muds, drill cuttings, 
    and well treatment fluids. This limitation requires that a discharge 
    shall not cause a film or sheen upon, or discoloration on, the surface 
    of the water or adjoining shorelines, or cause a sludge or emulsion to 
    be deposited beneath the surface of the water or upon adjoining 
    shorelines (40 CFR 435.11(d)). The BPT effluent limitation guideline 
    for sanitary waste required that the concentration of chlorine be 
    maintained as close to 1 mg/l as possible in discharges from facilities 
    housing ten or more persons. No floating solids are allowed as a result 
    of sanitary waste discharges from facilities continuously staffed by 
    nine or fewer persons or intermittently staffed by any number. A ``no 
    floating solids'' guideline also applies to domestic waste. BPT 
    limitations on oil and grease in produced water allowed a daily maximum 
    of 72 mg/l and a monthly average of 48 mg/l.
    2. BAT and BCT Effluent Limitations and New Source Performance 
    Standards
        As of March 31, 1989, all permits are required by section 301(b)(2) 
    of the Act to contain effluent limitations for all categories and 
    classes of point sources which: (1) Control toxic pollutants (40 CFR 
    401.15) and nonconventional pollutants through the use of Best 
    Available Technology Economically Achievable (BAT), and (2) represent 
    Best Conventional Pollutant Control Technology (BCT). BCT effluent 
    limitations apply to conventional pollutants (pH, BOD, oil and grease, 
    suspended solids, and fecal coliform). In no case may BCT or BAT be 
    less stringent than BPT.
        BAT and BCT effluent limitations guidelines and New Source 
    Performance Standards (NSPS) for the Offshore Subcategory were proposed 
    on August 26, 1985 (50 FR 34592) and signed on January 15, 1993 (58 FR 
    12454, March 4, 1993). The new guidelines were established under the 
    authority of sections 301(b), 304, 306, 307, 308, and 501 of the Act. 
    The new guidelines were also established in response to a Consent 
    Decree entered on April 5, 1990 (subsequently modified on May 28, 1993) 
    in NRDC v. Reilly, D. D.C. No. 79-3442 (JHP) and are consistent with 
    EPA's Effluent Guidelines Plan under section 304(m) of the CWA (57 FR 
    41000, September 8, 1992). The proposed existing source general permit, 
    incorporates BAT and BCT effluent limitations based upon the more 
    stringent standards of the recently promulgated effluent guidelines or 
    previous general permit existing requirements, and incorporate 
    additional discharge restrictions based on environmental data. The 
    proposed new source general permit is based on the recently promulgated 
    NSPS based on the best available demonstrated technology, and 
    incorporate additional discharge restrictions based on environmental 
    data. Since the March 4, 1993 Offshore Effluent Guidelines and New 
    Source Performance Standards basically set BAT limitations equal to 
    NSPS, the proposed limitations, conditions, and monitoring requirements 
    for today's proposed existing source general permit and new source 
    general permit are identical.
    3. Previous NPDES General Permit Limitations
        Per Section 402(o)(1) of the Clean Water Act and 40 CFR 122.44(l), 
    when a permit is reissued the effluent limitations must be as stringent 
    as the final effluent limitations of the previous permit unless the 
    circumstances on which the previous permit was based have materially 
    and substantially changed since the time the permit was issued. Part IV 
    of the fact sheet discusses the new or changed permit limitations and 
    conditions. All the
    
    [[Page 853]]
    
    limitations of the proposed NPDES general permit are as stringent or 
    more stringent as the previous permit effluent limitations and 
    conditions. The Alternative Toxicity Requests (ATRs) language of the 
    previous permit, which allowed more toxic muds to be discharged after a 
    case-by-case review, were invalidated by the Ninth Circuit Court; 
    therefore, all references to the ATR process are deleted from this 
    proposed NPDES general permit.
    
    B. Ocean Discharge Criteria
    
        Section 403 of the Act requires that an NPDES permit for a 
    discharge into marine waters located seaward of the inner boundary of 
    the territorial seas (i.e., state and federal offshore waters) be 
    issued in accordance with guidelines for determining the potential 
    degradation of the marine environment. These guidelines, referred to as 
    the Ocean Discharge Criteria (40 CFR Part 125, Subpart M), and section 
    403 of the Act are intended to ``prevent unreasonable degradation of 
    the marine environment and to authorize imposition of effluent 
    limitations, including a prohibition of discharge, if necessary, to 
    ensure this goal'' (49 FR 65942, October 3, 1980).
        If EPA determines that the discharge will cause unreasonable 
    degradation, an NPDES permit will not be issued. If a definitive 
    determination of no unreasonable degradation cannot be made because of 
    insufficient information, EPA must then determine whether a discharge 
    will cause irreparable harm to the marine environment and whether there 
    are reasonable alternatives to on-site disposal. To assess the 
    probability of irreparable harm, EPA is required to make a 
    determination that the discharger, operating under appropriate permit 
    conditions, will not cause permanent and significant harm to the 
    environment during a monitoring period in which additional information 
    is gathered. If data gathered through monitoring indicate that 
    continued discharge may cause unreasonable degradation, the discharge 
    shall be halted or additional permit limitations established.
        A preliminary Ocean Discharge Criteria Evaluation has been drafted. 
    Region 4 has determined that discharges occurring under the proposed 
    NPDES general permits, incorporating appropriate effluent limits and 
    monitoring requirements, will not cause unreasonable degradation for 
    existing and new source dischargers occurring in areas seaward of the 
    200-meter water depth in the Eastern Planning Area and seaward of the 
    outer boundary of the territorial seas in the Central Planning Area 
    (except in designated areas of biological concern).
    
    C. Section 308 of the Clean Water Act
    
        Under section 308 of the Act and 40 CFR 122.44(i), the Director 
    must require a discharger to conduct monitoring to determine compliance 
    with effluent limitations and to assist in the development of effluent 
    limitations. EPA has included several monitoring requirements in the 
    permit, as listed in the table in section VI.A of this fact sheet.
    
    V. Summary of New or Changed Permit Limitations and Conditions
    
        The following discussion is intended to provide a summary of the 
    parts of the proposed permit which are substantively different from the 
    1986 permit. For a detailed discussion of requirements and their bases, 
    please refer to Section VI of this fact sheet. Many of the new and 
    changed requirements result from promulgation of the final Effluent 
    Limitations Guidelines and New Source Performance Standards for the 
    Offshore Subcategory in March, 1993 (see 40 CFR Part 435, Subpart A).
    
    A. Alternative Toxicity Requests
    
        The existing OCS general permit contains a general toxicity 
    limitation on drilling fluids, prohibiting the discharge of fluids 
    having an aquatic toxicity LC50 value of less than 30,000 ppm of the 
    suspended particulate phase (SPP). Because the Regions believed that 
    some specific drilling operations might require the limited use of more 
    toxic drilling fluids, the permit also contained a procedure under 
    which an operator could submit an alternative toxicity request (ATR) 
    for approval by the Region. Region 4 did not approve any ATRs under the 
    existing general permit. Upon review, the Ninth Circuit Court 
    invalidated the ATR provisions of the current permit. Therefore, all 
    references to the ATR process are deleted from both proposed NPDES 
    general permits, making it consistent with the Court's decision.
    
    B. Cadmium and Mercury in Barite
    
        EPA Region 4 is implementing the selected option of the BAT/NSPS 
    effluent guidelines by limiting the amount of cadmium (Cd) and mercury 
    (Hg) discharged in drilling fluids to 3 mg of Cd/kg and 1 mg of Hg/kg 
    (dry weight) in the source barite used in drilling fluids. This 
    limitation also is consistent with the Ninth Circuit Court's decision 
    that operators should be required to use the cleanest source of barite 
    available. The limitations and monitoring requirements for cadmium and 
    mercury are the same for both the existing source and new source 
    general permits.
        The toxic pollutants cadmium and mercury are found in barite which 
    is added to drilling fluids as a weighting agent. Different types of 
    barite deposits contain varying concentrations of toxic pollutants, 
    with bedded deposits (referred to as ``clean'') containing the lowest 
    metal levels, while vein deposits have much higher concentrations of 
    trace metals. The Agency, when the OCS Gulf of Mexico general permit 
    was first issued, decided not to impose limits on cadmium and mercury 
    because of incomplete information on the availability of clean barite 
    for all Gulf operations. However, the Ninth Circuit Court held invalid 
    the Agency's decision not to impose any limitations on cadmium and 
    mercury in discharged drilling fluids and stated that ``EPA should 
    provide in the Gulf of Mexico permit, as it did in the Alaska permit, 
    that clean barite should be used as long as it is available.'' The BAT/
    NSPS limitations of this in both the existing source and new source 
    general permit are consistent with that decision.
        A representative sample of the stock barite shall be monitored and 
    reported once for each well or once for each additional supply of 
    barite received while drilling a well. If subsequent wells are drilled 
    at a site, new analyses are not required for each well if no new 
    supplies of barite are received since the previous analysis.
        The results for total mercury and cadmium shall be reported on the 
    monthly Discharge Monitoring Report (DMR) for each well drilled. If a 
    previous analysis is used in subsequent months or for subsequent wells, 
    the results of that analysis should be reported on the DMRs for the 
    later months and wells. If the supplier of the barite provides the 
    analysis to the operator, the concentration shall be reported on the 
    DMR with an indication that the information was provided by the 
    supplier. All reported analyses, whether performed by the permittee or 
    the supplier of the barite, shall be conducted by absorption 
    spectrophotometry (see 40 CFR Part 136, flame and flameless AAS) and 
    results expressed as mg/kg (dry weight) of barite.
    
    C. New Sources Performance Standards (NSPS)
    
        NSPS have been added to operations previously defined as new 
    sources in the fact sheet. In accordance with 58 FR 12456 of March 4, 
    1993, NSPS are based
    
    [[Page 854]]
    
    on the best available demonstrated technology. New plants have the 
    opportunity to install the best and most efficient production processes 
    and wastewater treatment technologies. Therefore, Congress directed EPA 
    to consider the best demonstrated process changes, in-plant controls 
    and treatment technologies that reduce pollution to the maximum extent 
    feasible. In addition, in establishing NSPS, EPA is required to take 
    into consideration the cost of achieving the effluent reduction and any 
    non-water impacts and energy requirements.
    
    D. Free Oil
    
        The existing NPDES general permit requires operators to use the 
    visual sheen test to monitor for free oil on the surface of the 
    receiving water when discharging muds and cuttings. This method can be 
    used only during daylight when weather and sea conditions are such that 
    observation of a sheen is possible. At all other times, discharge is 
    permitted provided that the operator used an alternate test, the static 
    (laboratory) sheen test, for monitoring for free oil. However, BAT and 
    NSPS effluent guidelines require the use of the static sheen test for 
    monitoring free oil at all times for discharges of muds and cuttings to 
    offshore waters. In these proposed NPDES general permits, Region 4 is 
    implementing the final effluent guidelines by requiring the static 
    sheen test as the monitoring requirement for detecting free oil in 
    drilling fluid and cuttings. The Region is requiring that this same 
    method be used for well treatment, completion, and workover fluid 
    discharges as well. In accordance with the final effluent guidelines, 
    free oil from deck drainage will continue to be monitored as in the 
    existing general permit by use of the visual sheen test. The Region 
    feels that the static sheen test is the appropriate test method for the 
    eastern Gulf of Mexico. Because the test is conducted prior to 
    discharge, it allows the operator to avoid potential costly violations 
    and affords more protection to the environment by requiring compliance 
    monitoring before the discharge has occurred. The test is to be 
    conducted in accordance with the methodology in the final effluent 
    guidelines (58 FR 12506; see permit Part IV.A.3). The number of times 
    that a sheen is observed shall be reported on the monthly DMR.
    
    E. Produced Sand
    
        The existing NPDES general permit requires operators to use the 
    visual sheen test to monitor for free oil on the surface of the 
    receiving water when discharging produced sand. This method can be used 
    only during daylight when weather and sea conditions are such that 
    observation of a sheen in the vicinity of the discharge is possible. 
    The final BAT and NSPS effluent guidelines for the offshore subcategory 
    prohibit the discharge of produced sand. EPA did not determine that the 
    prohibition is the ``best available'' or ``best demonstrated'' 
    technology. However, onshore disposal is widely practiced throughout 
    the industry to meet the no free oil limitations either due to 
    economics (cost of onsite washing is comparable to cost of onshore 
    disposal), logistic considerations (scheduling or space requirements), 
    or because of the inability to reliably meet the no free oil limitation 
    even after washing. Region 4 is implementing the final guidelines by 
    prohibiting the discharge of produced sand under both general permits.
    
    F. Produced Water
    
        The existing NPDES general permit established an effluent oil and 
    grease limit for produced water of 48 mg/l monthly average and 72 mg/l 
    daily maximum. The final effluent guidelines have established BAT and 
    NSPS oil and grease limitations for produced water discharges of 29 mg/
    l monthly average and 42 mg/l daily maximum. These limitations are 
    based on the use of gas flotation treatment technology which is 
    determined to be the best available technology economically achievable 
    for the offshore subcategory. Region 4 is implementing these 
    limitations in both NPDES general permits for the eastern Gulf of 
    Mexico OCS. Monitoring methods for this limitation are the same as 
    under the existing permit. Both the highest daily maximum concentration 
    and the monthly average concentration are reported on the monthly DMR.
    
    G. Diesel Oil Prohibition
    
        The existing OCS general permit contains provisions that 
    established the Diesel Pill Monitoring Program (DPMP), a 15-month study 
    to determine whether a diesel pill added to the mud system to free 
    stuck pipe could effectively be removed from a mud system after use. 
    Under the terms of the permit, the program was to last for one year 
    with a possible extension of up to one additional year. At the end of 
    the first year, EPA concluded that the DPMP had essentially reached its 
    limit for gathering data necessary for evaluating that issue, but found 
    some merit in extending the program for an additional 3-month period, 
    ending September 30, 1987.
        After the DPMP had expired, the existing general permit prohibited 
    the discharge of drilling fluids containing diesel oil unless: (1) The 
    diesel oil was added as a pill in an effort to free stuck pipe, (2) the 
    pill and 50-barrel buffers on either side of the pill were removed from 
    the drilling fluid system, (3) the remaining fluid to be discharged met 
    the 30,000 ppm LC50 toxicity limitation, and (4) the discharge of the 
    remaining fluid caused no visible sheen on the surface of the receiving 
    water. Data collected under the DPMP showed that diesel could not 
    effectively be removed from a drilling fluids system after use of a 
    pill. A substantial amount of diesel oil remains in the drilling fluids 
    system even after the pill and 100 barrels of drilling fluids system 
    are removed. Therefore, the proposed permit no longer allows the 
    discharge of drilling fluids to which a diesel pill has been added, 
    even when the pill and a 50-barrel buffer on either side are removed 
    from the system. Under the proposed reissuance, all references to the 
    DPMP are deleted from the permit and discharge of muds to which diesel 
    oil has been added is prohibited. However, both the proposed NPDES 
    existing source general permit and NSPS general permit would allow the 
    discharge of drilling fluids where non-diesel oils and mineral oils 
    have been introduced to the mud system while drilling, provided that 
    the mud system meets the toxicity and free oil limitations before 
    discharge.
    
    H. Water Quality-Based Effluent Limitations and Conditions
    
        The CWA states ``* * * it is the national policy that the discharge 
    of toxic pollutants in toxic amounts be prohibited. * * * '' To ensure 
    that the CWA's prohibitions on toxic discharges are met, EPA has issued 
    a ``Policy for the Development of Water Quality-Based Permit 
    Limitations for Toxic Pollutants'' (49 FR 9016; March 9, 1984). This 
    national policy states that an ``integrated strategy consisting of both 
    biological and chemical methods to address toxic and nonconventional 
    pollutants'' will be used to control pollutants beyond BAT. For NPDES 
    permits, these strategies include numerical limits for toxic pollutants 
    to assure compliance with state standards and use of biological 
    techniques and available data on chemical effects to assess toxicity 
    impacts and human health hazards based on the general standard of ``no 
    toxic materials in toxic amounts.''
        Based on available data, EPA has determined that there are 
    pollutants present in produced water discharges that have the potential 
    to cause toxic conditions in the receiving water or sediment in 
    violation of Section
    
    [[Page 855]]
    
    101(a)(3) of the CWA. Whole effluent biomonitoring is the most direct 
    measure of potential toxic effects that incorporates the effects of 
    synergism of effluent components. It is the national policy of EPA to 
    use toxicity tests to evaluate the toxic effects of a discharge upon a 
    receiving water (49 FR 9016, March 9, 1984). This proposed permit 
    establishes effluent limitations on the whole effluent toxicity of 
    produced water. Both the daily average and the monthly minimum toxicity 
    (96-hour LC50) value shall not be less than the limiting permissible 
    concentration at the edge of the mixing zone as defined in the Ocean 
    Discharge Criteria (40 CFR 125). The Ocean Discharge Criteria 
    incorporates the limiting permissible concentration definition of the 
    Ocean Dumping Criteria, which is ``0.01 of a concentration shown to be 
    acutely toxic to appropriate sensitive marine organisms in a bioassay'' 
    (40 CFR 227.27). The mixing zone is defined under the Ocean Discharge 
    Criteria (40 CFR 125.121(c)) as the zone extending from the sea's 
    surface to the seabed and extending 100 meters in all directions from 
    the discharge point. Therefore, the toxicity limitation of these 
    permits require that the discharged effluent meet a toxicity limitation 
    of an LC50 greater than the effluent concentration at the edge of the 
    mixing zone times 0.01. The method for determining this toxicity 
    limitation on a case-by-case basis is described below.
    
    I. Aquatic Toxicity Limits and Testing Requirements for Produced Water
    
        For produced water discharges, the Region is using a discharge 
    model to predict the effluent concentration that will occur at the edge 
    of a 100-meter mixing zone in order to calculate site-specific toxicity 
    limitations. The model will use parameters provided by the operator 
    (maximum discharge rate, water depth, discharge pipe diameter, and 
    discharge pipe orientation) as input. All other input parameters are 
    based on available data for the eastern Gulf of Mexico. Given these 
    parameters, the Region will calculate a toxicity limitation for each 
    facility before discharges may occur. The methodology for determining 
    the toxicity limitation for produced water, including derivation of the 
    input parameters, is detailed below.
        Because all future site-specific limitations cannot be anticipated 
    and commented on at this time, the Region is proposing the method by 
    which the toxicity limitations will be calculated. As part of this 
    method, the Region is establishing certain parameters of the variables 
    in the derivation as constant. These variables, or model input 
    parameters are discussed below. The Region solicits comments at this 
    time on the methodology for determining the effluent limitation and on 
    the selected input parameters. The Region will not be publicly noticing 
    all future produced water toxicity limitation determinations for the 
    duration of this permit.
        To establish a facility's produced water toxicity limit, an 
    operator must submit the information requested at Appendix A of the 
    permit. The necessary information for input in the CORMIX model 
    consists of: maximum discharge rate, minimum receiving water depth, 
    discharge pipe location (depth and orientation with respect to the 
    seafloor), and discharge pipe opening diameter. Parameters that are 
    proposed to remain constant for CORMIX input include effluent density, 
    ambient current speed, and the water column density profile. The 
    information will be used by the Region as input for the CORMIX expert 
    system (v. 1.4; Doneker and Jirka, 1990) to determine the projected 
    effluent concentration at the edge of the mixing zone in order to 
    calculate the toxicity limitation. Each month, the operator is required 
    to demonstrate compliance with this toxicity limitation by conducting 
    toxicity tests using Mysidopsis bahia and sheepshead minnows to 
    determine the 96-hour LC50s.
        The derivation/selection of the proposed constant parameters is 
    discussed below. The effluent density was determined from temperature 
    and salinity data submitted to the Louisiana Department of 
    Environmental Quality (DEQ) for produced water discharges to state 
    waters (Avanti Corporation, 1992). A density of 1,070.2 kg/m\3\ 
    represents a produced water with a salinity of 100 ppt (approximately 
    the lower 33rd percentile of all DEQ data) and a temperature of 105 
    deg.F (approximately the upper 90th percentile of the DEQ data).
        The current speed of 4 cm/sec represents the median of data 
    collected offshore Alabama using a current meter placed at a 10 meter 
    water depth in 30 meters of water (Texas A&M, 1991).
        The water column density profile is based on data reported for 
    offshore Alabama in Temple et al. (1977). Temperature and salinity data 
    for the 7-and 14-meter contours were used to determine the average 
    surface density and the average density gradient. The average surface 
    density reported for the monitoring year was 1,023 kg/m\3\ and the 
    average density gradient was 0.163 kg/m\3\/m. For each discharge 
    modeled, the average surface density is used with a bottom density 
    calculated as: [1,023 + (water depth  x  0.163)].
        Due to limitations of the model with respect to allowable discharge 
    pipe orientation, CORMIX is used with an inverted density profile and 
    run as a mirror image of actual discharge scenarios. This inversion 
    method, described in the Ocean Discharge Criteria Evaluation (Avanti 
    Corp., 1993a), reverses the actual scenario of a dense discharge from 
    the surface to a scenario of a buoyant discharge from the bottom. All 
    density differentials are held constant.
        Also, although CORMIX was determined to be the best model available 
    to predict discharges for OCS waters (LimnoTech and Wright, 1993), it 
    does underestimate far-field dilutions (Wright, 1993). In applying the 
    model to this permit, the Region is using an alternate method to 
    calculate the far-field dilution (the dilution that occurs after 
    initial mixing). For discharges that do not impact the bottom, Brook's 
    4/3 power law is used to determine the effluent dilution at the edge of 
    the mixing zone using input from CORMIX initial mixing projections.
        The resulting projected effluent concentration at 100 meters is 
    used by EPA to calculate the toxicity limitation (0.01  x  effluent 
    concentration = minimum LC50 limitation) for the outfall modeled. This 
    ensures that the discharge will not be acutely toxic beyond the 
    prescribed mixing zone. For example, using this methodology, for the 
    three outfalls currently discharging in the Mobile area, CORMIX (using 
    the 4/3 power law) projects dilutions of 83,721 for Block 908, 4,943 
    for Block 990, and 3,631 for Block 821. These dilutions result in 
    respective toxicity limitations of 1,200 ppm effluent; 20,000 ppm 
    effluent; and 27,500 ppm effluent. These limitations are minimum LC50 
    values for 96-hour tests. Other potential produced water discharges 
    occurring in the Gulf of Mexico would be subject to this produced water 
    toxicity limitation and will be determined upon initiation of a 
    produced water discharge and receipt of data requested by EPA in 
    Appendix A of the permit.
        The testing protocols for determining the 96-hour LC50s are 
    provided in ``Methods for Measuring the Acute Toxicity of Effluents to 
    Freshwater and Marine Organisms'' (EPA/600/4-85/013 or the most recent 
    update). The test must be conducted using Mysidopsis bahia and 
    sheepshead minnows (Cyprinodon variegatus). The permittee (or contract 
    laboratory) shall prepare and submit a full report of the results 
    according to the Report Preparation
    
    [[Page 856]]
    
    Section of the EPA methods manual. The original reports shall be 
    retained for three (3) years pursuant to the provisions of part II.C.5 
    of the permit. The LC50s must be reported monthly, accompanied by a 
    copy of the full laboratory report.
        Although the produced water itself may not greatly vary in quality 
    on the short term, many toxic chemicals such as biocides, corrosion 
    inhibitors, pipe descalers, and paraffin inhibitors are discharged in 
    produced waters and may affect the toxicity. The proposed permits 
    require operators to collect samples that are representative of the 
    discharge when these chemicals are being used. Logistically it may be 
    difficult for operators covered under these permits to collect and ship 
    additional effluent samples to be used for replacement water during the 
    biomonitoring test, so the proposed permits allow the permittees to 
    collect only one effluent sample to be used for all replicates in the 
    biomonitoring test. The proposed permits also allow operators to use 
    synthetic dilution water to minimize logistical and transportation 
    problems associated with sample collection.
    
    J. Discharge Prohibition in Vicinity of Areas of Biological Concern
    
        The NPDES General permit prohibits the discharges of drilling 
    fluids, drill cuttings and produced waters within 1000 meters from the 
    edge of an area of biological concern. The 1000 meter minimum distance 
    for discharge near areas of biological concern and no activity areas is 
    based on environmental study data that demonstrate the potential for 
    acute and chronic biological and ecological impacts due to exposure to 
    drilling fluids and produced water discharges at distances in the 1000-
    2000 meter range. Environmental studies consistently and conclusively 
    demonstrate significant chemical and biological changes from drilling 
    fluids and cuttings discharges at distances within 500 meters and 2000-
    3000 meters for frequent chemical occasional biological changes. 
    Chemical and biological impacts as a result of produced water 
    discharges are greatest in the 100-300 meter range and elevations of 
    chemical contaminants have been detected in the 1000-2000 meter range.
    
    K. Rubbish, Trash, and Other Refuse (MARPOL)
    
        Under Annex V to the International Convention for the Prevention of 
    Pollution from Ships, 1973 (MARPOL 73/78), the U.S. Coast Guard (USCG) 
    issued regulations on the disposal of domestic waste from all fixed or 
    floating offshore platforms and vessels engaged in exploration or 
    exploitation of seabed mineral resources (33 CFR 151). As specified by 
    33 U.S.C. 1901, those regulations apply to all navigable waters of the 
    U.S. (including the entire Gulf of Mexico), and are included in both 
    the existing source general permit and the new source general permit.
        As proposed, these permits prohibit the discharge of ``garbage,'' 
    including food wastes, from facilities located within 12 nautical miles 
    from nearest land. Comminuted food waste that is able to pass through a 
    screen with a mesh size no larger than 25 mm (approximately 1 inch) may 
    be discharged 12 or more nautical miles from the nearest land. 
    Incineration ash and non-plastic clinkers that can pass through a 25 mm 
    mesh screen may be discharged beyond 3 nautical miles from nearest 
    land. Otherwise ash and non-plastic clinkers may be discharged only 
    beyond 12 nautical miles from nearest land.
        Under these general permits, these limitations, which are already 
    effective under the USCG regulations, will be incorporated for 
    consistency purposes. Because graywater discharges from dishwater, 
    showers, baths, laundries, and washbasins are not subject to these USCG 
    regulations, they will remain subject to the same requirements for 
    domestic waste as under the expired OCS general permit.
    
    L. 24-Hour Reporting Requirement
    
        The Region is proposing to clarify several specific situations 
    where discharges occur that require oral reporting under the 24-hour 
    reporting requirement. They include: the discharge of 1 barrel or more 
    of oil from any permitted waste stream (this does not include spills 
    reported to the National Response Center as regulated under Section 311 
    of the Clean Water Act), the discharge of muds or cuttings which do not 
    meet the 30,000 ppm toxicity limitation, and any discharge of oil-based 
    muds or cuttings. Under the proposed permits, a permittee must verbally 
    notify the Regional office within 24 hours of the time at which the 
    permittee becomes aware of the discharge. A written submission must 
    also be provided within 5 days of the time the permittee becomes aware 
    of the circumstances. The written submission must contain a description 
    of the noncompliance and its cause; the period of noncompliance, 
    including exact dates and times; and if the noncompliance has not been 
    corrected, the anticipated time it is expected to continue; and steps 
    taken or planned to reduce, eliminate, and prevent reoccurrence of the 
    noncompliance. The Regional Administrator may waive the written report 
    on a case-by-case basis if the oral report has been received within 24 
    hours. The 24-hour reporting number for Region 4 is located in Part 
    II.D.7 of the permit.
    
    M. Reopener Clause
    
        These permits shall be modified, or alternately, revoked and 
    reissued to comply with any effluent standard or limitation, or sludge 
    disposal requirement issued or approved under Sections 301(b)(2)(C) and 
    (D), 307(a)(2), and 405(d)(2)(D) of the Clean Water Act, as amended, if 
    the effluent standard or limitation, or sludge disposal requirement so 
    issued or approved:
        a. Contains different conditions or is otherwise more stringent 
    than any condition in the permit; or
        b. Controls any pollutant or disposal method not addressed in the 
    permit.
        The permits as modified or reissued under this paragraph shall also 
    contain any other requirements of the Act then applicable.
        Further, the RA may at anytime require a general permit holder to 
    apply for an individual permit, as set forth in 40 CFR Section 
    122.28(b)(3).
    
    N. Clarifications
    
        The Region is taking this opportunity to clarify definitions, end 
    of well sampling requirements, and the visual and static sheen tests. 
    These clarifications are not new definitions; they are further 
    clarifications of the Agency's original intent of their application.
    Boiler Blowdown
        Existing: Discharges from boilers necessary to minimize solids 
    build-up in the boilers.
        Clarification: Discharges from boilers necessary to minimize solids 
    build-up in the boilers, including vents from boilers and other heating 
    systems.
    Completion Fluids
        Existing: Any fluids used in a newly drilled well to allow safe 
    preparation of the well for production.
        Clarification: Salt solutions, weighted brines, polymers and 
    various additives used to prevent damage to the wellbore during 
    operations which prepare the drilled well for hydrocarbon production. 
    These fluids prevent solid loss, prepare a well for production, provide 
    hydrostatic control and prevent formation damage.
    Deck Drainage
        Existing: All waste resulting from platform washings, deck 
    washings, and
    
    [[Page 857]]
    
    runoff from curbs, gutters, and drains, including drip pans and wash 
    areas.
        Clarification: All waste resulting from platform washings, deck 
    washings, work area spills, rainwater, and runoff from curbs, gutters, 
    and drains, including drip pans and work areas.
    Domestic Waste
        Existing: Discharges from galleys, sinks, showers, and laundries 
    only.
        Clarification: Discharges from galleys, sinks, showers, safety 
    showers, eye wash stations, and laundries.
    Muds, Cuttings, and Cement at the Seafloor
        Existing: Discharges that occur at the seafloor prior to 
    installation of the marine riser.
        Clarification: Discharges that occur at the seafloor prior to 
    installation of the marine riser and during marine riser disconnect, 
    well abandonment and plugging operations.
    Produced Sand
        Existing: Sand and other solids removed from the produced waters.
        Clarification: Slurried particles used in hydraulic fracturing, the 
    accumulated formation sands and scales particles generated during 
    production. Produced sand also includes desander discharge from the 
    produced water waste stream and blowdown of the water phase from 
    produced water treating systems.
    Produced Water
        Existing: Water and particulate matter associated with oil and gas 
    producing formations.
        Clarification: Water (brine) brought up from the hydrocarbon-
    bearing strata during the extraction of oil and gas, and can include 
    formation water, injection water, and any chemicals added downhole or 
    during the oil/water separation process.
    Well Treatment Fluids
        Existing: Any fluid used to enhance production by physically 
    altering oil-bearing strata after a well has been drilled.
        Clarification: Any fluid used to restore or improve productivity by 
    chemically or physically altering hydrocarbon-bearing strata after a 
    well has been drilled. These fluids move into the formation and return 
    to the surface as a slug with the produced water. Stimulation fluids 
    include substances such as acids, solvents, and propping agents.
    Workover Fluids
        Existing: Any fluid used in a producing well to allow safe repair 
    and maintenance or abandonment procedures.
        Clarification: Salt solutions, weighted brines, polymers and other 
    specialty additives used in a producing well to allow safe repair and 
    maintenance or abandonment procedures. These fluids prevent solid loss, 
    prepare a well for production, provide hydrostatic control and prevent 
    formation damage. Packer fluids, low solids fluids between the packer, 
    production string and well casing, are considered to be workover fluids 
    and must meet only the effluent requirements imposed on workover 
    fluids. High-solids drilling fluids used during workover operations are 
    not considered workover fluids by definition, and therefore must meet 
    drilling fluid effluent limitations before discharge may occur.
    End of Well Sample
        Existing: The end of well definition in the existing Gulf of Mexico 
    OCS general permit requires that a sample be taken at the point when 
    total well depth is reached. The original intent of the end of well 
    sample was to characterize the mud system just prior to being 
    discharged. It is now known that several weeks may pass after the well 
    has reached maximum drilled depth before the actual discharge of the 
    mud system. Formation evaluation (running logs, drill stem tests, etc.) 
    and completion operations such as setting pipe may all occur after 
    reaching total drilled depth while still using the same drilling fluid 
    used to drill the well. For this reason, the end of well sample 
    definition is being changed to read as below:
        Changed: The sample taken no more than 48 hours prior to bulk 
    discharge and after any additives are introduced in order to best 
    characterize the mud systems being discharged.
        The type of sample required is a grab sample, taken from beneath 
    the shale shaker, or if there are no returns across the shaker, then 
    the sample must be from a location that is characteristic of the 
    overall mud system to be discharged. An end of well sample, as a daily 
    minimum, must be taken no more than 48 hours prior to bulk discharge. 
    If any additional additives are introduced to the mud system during 
    this 48-hour period, then a new sample must be collected, analyzed, and 
    will be recorded as the end of well sample. The purpose of this sample 
    is to accurately characterize the mud system that is being discharged.
    Static Sheen Test
        The static sheen test may be used as an alternative method to 
    detect free oil in place of the visual sheen test at night or when 
    atmospheric or surface conditions prohibit the observer from detecting 
    a sheen (e.g., rough seas, rainy weather, etc.). The test shall be 
    conducted in accordance with the methodology presented in the permit at 
    Part IV.A.3.
    Visual Sheen Test
        The visual sheen test procedure is being added to the text in order 
    to clarify the test methodology: The visual sheen test is used to 
    detect free oil by observing the surface of the receiving water for the 
    presence of a sheen while discharging. A sheen is defined as a 
    ``silvery'' or ``metallic'' sheen, gloss, or increased reflectivity; 
    visual color; iridescence; or oil slick on the surface. The operator 
    must conduct a visual sheen test only at times when a sheen could be 
    observed. This restriction eliminates observations at night or when 
    atmospheric or surface conditions prohibit the observer from detecting 
    a sheen (e.g., during rain or rough seas, etc.). Certain discharges can 
    only occur if a visual sheen test can be conducted.
        The observer must be positioned on the rig or platform, relative to 
    both the discharge point and current flow at the time of discharge, 
    such that the observer can detect a sheen should it surface down 
    current from the discharge. For discharges that have been occurring for 
    at least 15 minutes previously, observations may be made any time 
    thereafter. For discharges of less than 15 minutes duration, 
    observations must be made both during discharge and 5 minutes after 
    discharge has ceased.
    
    VI. Permit Conditions
    
    A. Determination of Discharge Conditions
    
        The determination of appropriate conditions for each discharge was 
    accomplished through:
        (1) Consideration of technology-based effluent limitations to 
    control conventional pollutants under BCT,
        (2) Consideration of technology-based effluent limitations to 
    control toxic and nonconventional pollutants under BAT,
        (3) Consideration of technology-based effluent limitations to 
    control toxic and nonconventional pollutants under NSPS,
        (4) Consideration of more stringent permit conditions of existing 
    general permit in accordance with Section 402(o)(1) of the Clean Water 
    Act.
        (5) Evaluation of the Ocean Discharge Criteria for discharges in 
    the Offshore Subcategory (given conditions 1 thru 4 are in place).
        EPA first determines which technology-based limits are required
    
    [[Page 858]]
    
    and then evaluates the effluent quality expected to result from these 
    controls. If water quality violations could occur as a result of 
    discharge, EPA must include water quality-based limits in the permit. 
    The permit limits will thus reflect whichever limits (technology-based 
    or water quality-based) are most stringent. Finally, an Ocean Discharge 
    Criteria Evaluation (ODCE) has been prepared to identify any additional 
    impacts created by these proposed discharges.
        General area and depth related requirements and 403(c) flow rate 
    requirements are discussed in section VI.B. and VI.C of this fact 
    sheet. For convenience, these conditions and the regulatory basis for 
    each are cross-referenced by discharge in Table 2 below:
    
    ----------------------------------------------------------------------------------------------------------------
                                               Statutory basis/                                                     
       Discharge and permit conditions         existing sources                Statutory basis/new sources          
    ----------------------------------------------------------------------------------------------------------------
    Produced Water:                                                                                                 
        Monitor Flow (MGD)...............  Sec.  308..............  Sec.  308.                                      
        Oil & Grease.....................  BCT, BAT...............  NSPS.                                           
        Whole Effluent Toxicity (WET)....  Water Quality Standards  Water Quality Standards.                        
        >200 meters EPA--No Unreasonable   Sec.  403..............  Sec.  403, EIS.                                 
         Degradation.                                                                                               
        >1000 meters from Area of          Sec.  403..............  Sec.  403.                                      
         Biological Concern--No                                                                                     
         Unreasonable Degradation.                                                                                  
    Well Treatment, Completion, &                                                                                   
     Workover Fluids:                                                                                               
        Monitor Frequency/Flow Rate......  Sec.  308..............  Sec.  308.                                      
        No Free Oil......................  BPT, BCT...............  NSPS.                                           
        Oil & Grease.....................  BAT....................  NSPS.                                           
        >200 meters EPA--No Unreasonable   Sec.  403..............  Sec.  403, EIS.                                 
         Degradation.                                                                                               
    Deck Drainage:                                                                                                  
        Monitor Frequency/Flow Rate......  Sec.  308..............  Sec.  308.                                      
        No Free Oil......................  BPT, BCT, BAT..........  NSPS.                                           
        >200 meters--No Unreasonable       Sec.  403..............  Sec.  403, EIS.                                 
         Degradation.                                                                                               
    Produced Sand:                                                                                                  
        No Discharge Allowed.............  BCT, BAT...............  NSPS.                                           
    Sanitary Waste (manned by 10 or                                                                                 
     more):                                                                                                         
        Residual Chlorine................  BPT, BAT...............  NSPS.                                           
        >200 meters EPA--No Unreasonable   Sec.  403..............  Sec.  403, EIS.                                 
         Degradation.                                                                                               
    Sanitary Waste (manned by 9 or less):                                                                           
        No Floating Solids...............  BPT, BCT...............  NSPS.                                           
        >200 meters EPA--No Unreasonable   Sec.  403..............  Sec.  403, EIS.                                 
         Degradation.                                                                                               
    Domestic Waste:                                                                                                 
        No Foam..........................  BAT....................  NSPS.                                           
        No Floating Solids...............  BCT/BAT................  NSPS.                                           
        >200 meters EPA--No Unreasonable   Sec.  403..............  Sec.  403, EIS.                                 
         Degradation.                                                                                               
    Well Test Fluids:                                                                                               
        Monitor Frequency/Flow Rate......  Sec.  308..............  Sec.  308.                                      
        No Free Oil......................  BCT, BAT...............  BCT, BAT.                                       
        >200 meters EPA--No Unreasonable   Sec.  403..............  Sec.  403, EIS.                                 
         Degradation.                                                                                               
    Minor Wastes:                                                                                                   
        Desalination Unit Discharge, Blow                                                                           
         Out Preventer Fluids,                                                                                      
         Uncontaminated Ballast Water,                                                                              
         Muds Cuttings & Cement at                                                                                  
         Seafloor, Uncontaminated Sea                                                                               
         Water, Fire Test Water, Boiler                                                                             
         Blowdown, Excess Cement Slurry,                                                                            
         Diatomaceous Earth Filter Media,                                                                           
         Uncontaminated Fresh Water,                                                                                
         Noncontaminated Fresh Water                                                                                
            No Free Oil..................  BCT, BAT...............  BCT, BAT.                                       
            >200 meters EPA--No            Sec.  403..............  Sec.  403.                                      
             Unreasonable Degradation.                                                                              
    ----------------------------------------------------------------------------------------------------------------
    
    B. Area and Depth-Related Requirements
    
        The discharge restrictions and requirements listed below are 
    necessary to ensure that unreasonable degradation of these areas will 
    not occur as discussed above in part III.B. of this fact sheet (Ocean 
    Discharge Criteria) and are largely unchanged from the 1986 permit to 
    the proposed permit. Discharge within the area described below the 
    26 deg. parallel is prohibited due to a order which establishes a 
    moratorium on drilling activity on leases in that area.
        Pertaining to all discharges, these NPDES general permits only 
    provide coverage for discharges occurring:
    
        --In water depths greater than 200 meters in the Eastern Planning 
    Area (as measured from mean low water).
        --In waters seaward of the outer boundary of the territorial seas 
    in the Central Planning Area, except designated areas of biological 
    concern.
        --For leases not under moratorium; which is currently areas above 
    the 26 deg. parallel.
    
    C. Section 403(c) Requirements for Muds and Cuttings
    
        Flow rates: In addition to restrictions on all discharges imposed 
    under section 403(c) of the Act and discussed in section III.B. of this 
    fact sheet, muds and cuttings discharges are limited to the following 
    maximum rates. These limitations are identical to those contained in 
    the 1986 general permit.
        1,000 bbl/hr on total muds and cuttings. This limit was established 
    in the previous 1986 permit because reliable dispersion data are 
    available only up to this discharge rate and because this rate did not 
    represent any serious operational problem based on comments received 
    from the industry and discharge monitoring reports.
    
    VII. Other Legal Requirements
    
    National Environmental Policy Act
    
        Under the direction of the National Environmental Policy Act 
    (NEPA), EPA and MMS entered into a Memorandum of Understanding to 
    coordinate efforts on environmental impact statements
    
    [[Page 859]]
    
    (EIS) for areas covered by new source performance standards before EPA 
    issues final permits covering discharges. EPA has completed a draft EIS 
    for this general permit and is accepting public comment on that 
    document. A final EIS will be prepared before issuance of the final 
    permit. EPA also will coordinate with MMS for complying with NEPA for 
    specific new source (production) projects.
    
    Oil Spill Requirements
    
        Section 311 of the Clean Water Act prohibits the discharge of oil 
    and hazardous materials in harmful quantities. Routine discharges that 
    are in compliance with NPDES permits are excluded from the provisions 
    of section 311. However, the permits do not preclude the institution of 
    legal action or relieve permittees from any responsibilities, 
    liabilities, or penalties for other, unauthorized discharges of oil and 
    hazardous materials that are covered by section 311 of the Act.
    
    Endangered Species Act
    
        The Endangered Species Act (ESA) allocates authority to, and 
    administers requirements upon, federal agencies regarding endangered 
    species of fish, wildlife, or plants that have been designated as 
    critical. Its implementing regulations (50 CFR Part 402) require the RA 
    to ensure, in consultation with the Secretaries of Interior and 
    Commerce, that any action authorized, funded or carried out by EPA is 
    not likely to jeopardize the continued existence of any endangered or 
    threatened species or adversely affect its critical habitat (40 CFR 
    122.49(c)). Implementing regulations for the ESA establish a process by 
    which agencies consult with one another to ensure that issues and 
    concerns of both the National Marine Fisheries Service (NMFS) and the 
    U.S. Fish and Wildlife Service (USFWS) collectively are addressed. The 
    NMFS and USFWS have responded to EPA's initiation of the coordination 
    process under the regulations set forth by section 7 of the Endangered 
    Species Act. The 36 species identified by NMFS and USFWS as threatened 
    or endangered species within the permit coverage area have been 
    assessed for potential effects from the activities covered by the 
    proposed permit in a biological assessment incorporated in the Draft 
    EIS. This biological assessment has been submitted to the NMFS and 
    USFWS along with the proposed permit for consistency review and 
    concurrence on the Region's finding of no adverse effect. The Region's 
    finding is appended to the EIS.
    
    Ocean Discharge Criteria Evaluation
    
        For discharges into waters located seaward of the inner boundary of 
    the territorial seas, the Clean Water Act at section 403, requires that 
    NPDES permits consider guidelines for determining the potential 
    degradation of the marine environment. The guidelines, or Ocean 
    Discharge Criteria (40 CFR part 125, subpart M), are intended to 
    ``prevent unreasonable degradation of the marine environment and to 
    authorize imposition of effluent limitations, including a prohibition 
    of discharge, if necessary, to ensure this goal'' (45 FR 65942, October 
    3, 1980). After all available comments and information are reviewed, 
    the final 403 determination will be made.
        A revised preliminary Ocean Discharge Criteria Evaluation (ODCE) 
    determination of no unreasonable degradation has been made by Region 4 
    based on an analysis by Avanti Corporation (1993a). The potential 
    effects of discharges under the proposed permit limitations and 
    conditions are assessed in this draft document available from Region 4. 
    The ODCE states that, based on the available information, the permit 
    limitations are sufficient to determine that no unreasonable 
    degradation should result from the permitted discharges.
    
    Coastal Zone Management Act
    
        The coverage area of the proposed general permit includes only 
    Federal waters of the eastern Gulf of Mexico. However, the State waters 
    of Florida, Alabama, and Mississippi are potentially affected by 
    activities covered under the permit. Therefore, the coastal zone 
    management plans of Florida, Alabama, and Mississippi have been 
    reviewed for consistency and consultation with the states for 
    consistency concurrence has been initiated. A consistency determination 
    for each state and the proposed permit have been submitted for state 
    review. The consistency determinations are appended to the EIS.
    
    Marine Protection, Research, and Sanctuaries Act
    
        No marine sanctuaries as designated by the Marine Protection, 
    Research, and Sanctuaries Act exist in the area to which the OCS permit 
    applies.
    
    Executive Order 12291
    
        The Office of Management and Budget has exempted this action from 
    the review requirements of Executive Order 12291 pursuant to section 
    8(b) of that order.
    
    Paperwork Reduction Act
    
        The information collection required by these permits has been 
    approved by the Office of Management and Budget (OMB) under the 
    provisions of the Paperwork Reduction Act, 44 U.S.C. 3501 et seq., in 
    submission made for the NPDES permit program and assigned OMB control 
    numbers 2040-0086 (NPDES permit application) and 2040-0004 (discharge 
    monitoring reports).
        All facilities affected by these permits must submit a notice of 
    intent to be covered under the eastern Gulf of Mexico OCS general 
    permit GMG280000. EPA estimates that it will take an affected facility 
    three hours to prepare the request for coverage.
        All affected facilities will be required to submit discharge 
    monitoring reports (DMRs). EPA estimated DMR burden for the existing 
    permit to be 36 hours per facility per year. The DMR burden for these 
    proposed permits is expected to increase slightly due to the additional 
    reporting required for calculating the critical dilution for produced 
    water discharges. While this permit requires some increased monitoring 
    and reporting of that data, the DMR burden for the proposed permits is 
    estimated to increase slightly and facilities affected by this permit 
    reissuance were subject to similar information collection burdens under 
    the existing Gulf of Mexico OCS general permit that this proposed 
    reissuance will replace.
    
    Regulatory Flexibility Act
    
        After review of the facts presented above, I hereby certify, 
    pursuant to the provisions of 5 U.S.C. 605(b), that these proposed 
    general permits will not have a significant impact on a substantial 
    number of small entities. This certification is based on the fact that 
    the vast majority of the parties regulated by this permit have greater 
    than 500 employees and are not classified as small businesses under the 
    Small Business Administration regulations established at 49 FR 5024 et 
    seq. (February 9, 1984). For those operators having fewer than 500 
    employees, this permit issuance will not have significant economic 
    impact. These facilities are classified as Major Group 13--Oil and Gas 
    Extraction SIC Crude Petroleum and Natural Gas.
    
    Proposed Schedule for Permit Issuance
    
        Draft Permit to Federal Register for Public Notice--January 2, 
    1998.
        Close Comment Period--February 16, 1998.
    
    [[Page 860]]
    
        Dated: [Signature date]
    Regional Administrator,
    Regional Administrator, Region 4.
    
    References
    
    ASTM. 1990. Standard Guide for Collection, Storage, 
    Characterization, and Manipulation of Sediments for Toxicological 
    Testing. Under jurisdiction of ASTM Committee E-47 on Biological 
    Effects and Environmental Fate. ASTM Designation E 1391-90.
    ASTM. 1992. Standard Guide for Conducting 10-day Static Sediment 
    Toxicity Tests with Marine and Estuarine Amphipods. Under 
    jurisdiction of ASTM Committee E-47 on Biological Effects and 
    Environmental Fate. ASTM Designation E 1367-92.
    Avanti Corporation. 1992. Characterization of Data Collected from 
    the Louisiana Department of Environmental Quality Permit Files for 
    Development of Texas and Louisiana Coastal Subcategory NPDES General 
    Permits. Submitted to EPA Region 6, Water Management Division.
    Avanti Corporation. 1993a. Ocean Discharge Criteria Evaluation for 
    the NPDES General Permit for the Eastern Gulf of Mexico--Draft. 
    Submitted to U.S. EPA Region 4, Water Management Division.
    Avanti Corporation. 1993b. Biological Assessment for the NPDES 
    General Permit for Oil and Gas Exploration, Development, and 
    Production Activities on the Eastern Gulf of Mexico OCS. Submitted 
    to U.S. EPA Region 4, Water Management Division.
    Doneker, R.L. and G.H. Jirka. 1990. Expert System for Hydrodynamic 
    Mixing Zone Analysis of Conventional and Toxic Submerged Single Port 
    Discharges (CORMIX1). Prepared by Cornell University for U.S. EPA, 
    Environmental Research Laboratory, Athens, GA. EPA/600/3-90/012.
    Gannett Fleming, Inc. 1995. Draft Supplemental Environmental Impact 
    Statement For National Pollutant Discharge Elimination System 
    Permitting For Gulf of Mexico Offshore Oil and Gas Extraction. EPA 
    904/9-95-001A.
    LimnoTech, Inc. and S. Wright. 1993. Recommendation of Specific 
    Models to Evaluate Mixing Zone Impacts of Produced Water Discharges 
    to the Western Gulf of Mexico Outer Continental Shelf. Prepared for 
    U.S. EPA, Region 6.
    MMS. 1992. Outer Continental Shelf Natural Gas and Oil Resource 
    Management, Comprehensive Program 1992-1997, Proposed Final Summary 
    and Decision. U.S. Department of the Interior, MMS, Washington, DC.
    Minerals Management Service. 1997. Gulf of Mexico Sales 169, 172, 
    175, 178, and 182: Central Planning Area Draft EIS. US Department of 
    the Interior, MMS, Gulf of Mexico OCS Region, New Orleans, LA
    Schroeder, W.W., A.W. Shultz and J.J. Dindo. 1988. Inner-Shelf 
    Hardbottom Areas, Northeastern Gulf of Mexico. Trans. Gulf Coast 
    Assoc. of Geological Soc., 38:535-541.
    Temple, R.F., D.L. Harrington, and J.A. Martin. 1977. Monthly 
    Temperature and Salinity Measurements of Continental Shelf Waters of 
    the Northwestern Gulf of Mexico, 1963-1965. NOAA Tech. Rep. SSRF-
    707. 29 pp.
    Texas A&M University. 1991. Mississippi-Alabama Continental Shelf 
    Ecosystem Study, Data Summary and Synthesis. Prepared for MMS Gulf 
    of Mexico OCS Region. MMS 91-0064.
    Wright, S.J. 1993. Analysis of CORMIX1 and UM/PLUMES Predictive 
    Ability for Buoyant Jets in a Density-Stratified Flow. Prepared for 
    U.S. EPA Office of Wastewater Enforcement and Compliance.
    
    GENERAL PERMIT TABLE OF CONTENTS
    
    Part I. Requirements for NPDES Permits
    Section A. Permit Applicability and Coverage Conditions
        1. Operations Covered
        2. Operations Excluded
        3. General Permit Applicability
        4. Notification Requirements
        5. Termination of Operations
        6. Intent to be Covered by a Subsequent Permit
    Section B. Effluent Limitations and Monitoring Requirements
        1. Drilling Fluids
        2. Drill Cuttings
        3. Produced Water
        4. Deck Drainage
        5. Produced Sand
        6. Well Treatment Fluids, Completion Fluids, and Workover Fluids
        7. Sanitary Waste (Facilities Continuously Manned by 10 or More 
    Persons)
        8. Sanitary Waste (Facilities Continuously Manned by 9 or Fewer 
    Persons or Intermittently by Any Number)
        9. Domestic Waste
        10. Miscellaneous Discharges (Desalination Unit Discharge, 
    Blowout Preventer Fluid, Uncontaminated Ballast Water, 
    Uncontaminated Bilge Water, Mud, Cuttings, and Cement at the 
    Seafloor, Uncontaminated Seawater, Boiler Blowdown, Source Water and 
    Sand, and Diatomaceous Earth Filter Media)
    Section C. Other Discharge Limitations
        1. Floating Solids or Visible Foam
        2. Halogenated Phenol Compounds
        3. Dispersants, Surfactants, and Detergents
        4. Rubbish, Trash, and Other Refuse
        5. Areas of Biological Concern
    Part II. Standard Conditions for NPDES Permits
    Section A. Introduction and General Conditions
        1. Duty to Comply
        2. Penalties for Violations of Permit Conditions
        3. Duty to Mitigate
        4. Permit Flexibility
        5. Toxic Pollutants
        6. Civil and Criminal Liabilities
        7. Oil and Hazardous Substance Liability
        8. State Laws
        9. Property Rights
        10. Onshore or Offshore Construction
        11. Severability
        12. Duty to Provide Information
    Section B. Proper Operation and Maintenance of Pollution Controls
        1. Proper Operation and Maintenance
        2. Need to Halt or Reduce not a Defense
        3. Bypass of Treatment Facilities
        4. Upset Conditions
        5. Removed Substances
    Section C. Monitoring and Records
        1. Representative Sampling
        2. Discharge Rate/Flow Measurements
        3. Monitoring Procedures
        4. Penalties for Tampering
        5. Retention of Records
        6. Record Contents
        7. Inspection and Entry
    Section D. Reporting Requirements
        1. Planned Changes
        2. Anticipated Noncompliance
        3. Transfers
        4. Monitoring Reports
        5. Additional Monitoring by the Permittee
        6. Averaging of Measurements
        7. Twenty-four Hour Reporting
        8. Other Noncompliance
        9. Other Information
        10. Changes in Discharges of Toxic Substances
        11. Duty to Reapply
        12. Signatory Requirements
        13. Availability of Reports
    Part III. Monitoring Reports and Permit Modification
    Section A. Monitoring Reports
    Section B. Permit Modification
    Part IV. Test Procedures and Definitions
    Section A. Test Procedures
        1. Samples of Wastes
        2. Drilling Fluids Toxicity Test
        3. Static (Laboratory) Sheen Test
        4. Visual Sheen Test
        5. Produced Water Acute Toxicity Test
        6. Retort Test
    Section B. Definitions
    Table 2. Effluent Limitations, Prohibitions, and Monitoring 
    Requirements for the Eastern Gulf of Mexico NPDES General Permit 
    (Existing Sources)
    Table 3. Effluent Limitations, Prohibitions, and Monitoring 
    Requirements for the Eastern Gulf of Mexico NPDES General Permit 
    (New Sources)
    Appendix A
    Table A-1. CORMIX1 Input Parameters for Toxicity Limitation 
    Calculation
    Appendix B. Map Identifying Areas of Biological Concern in the 
    Central Planning Area.
    
    Authorization To Discharge Under the National Pollutant Discharge 
    Elimination System
    
        In compliance with the Federal Water Pollution Control Act, as 
    amended (33 U.S.C. 1251 et seq.), operators of lease blocks located in 
    OCS Federal waters seaward of 200 meters in the Eastern Planning Area 
    and seaward of the outer boundary of the territorial seas in the 
    Central Planning Area with existing source or new source discharges 
    originating from exploration or development and production operations 
    are authorized to discharge to receiving waters in accordance with 
    effluent limitations, monitoring requirements, and other conditions set 
    forth in parts I, II, III, and IV hereof.
        Operators of operating facilities within the proposed NPDES general
    
    [[Page 861]]
    
    permit area must submit written notification to the Regional 
    Administrator, prior to discharge, that they intend to be covered by 
    either the existing source general permit or the new source general 
    permit (See part I.A.3). Upon receipt of notification of inclusion by 
    the Regional Administrator, owners or operators requesting coverage are 
    authorized to discharge under either the existing source or new source 
    general permit. Operators of lease blocks within the general permit 
    area who fail to notify the Regional Administrator of intent to be 
    covered by this general permit are not authorized under the general 
    permit to discharge pollutants from their potential new or existing 
    source facilities. This permit does not apply to non-operational 
    leases, i.e., those on which no discharge has taken place in 2 years 
    prior to the effective date of the new general permits. EPA will not 
    accept Notice of Intents (NOI's) from such leases, and these general 
    permits will not cover such leases. Non-operational leases will lose 
    general permit coverage on the effective date of these new general 
    permits.
        This permit shall become effective at [time], Eastern Standard 
    Time, on [Month, Day, 19  ]. Coverage under the old general permit 
    shall terminate on the effective date of this permit, unless the owner/
    operator submits a notice of intent (NOI) to be covered within 60 days 
    thereafter, or an application for an individual permit within 120 days 
    thereafter. If an NOI is filed, coverage under the old general permit 
    terminates upon receipt of notification of inclusion by letter from the 
    Director of the Water Management Division, Region 4. If a permit 
    application is filed, the old general permit terminates when a final 
    action is taken on the application for an individual permit. This 
    permit and the authorization to discharge shall expire [time], Eastern 
    Standard Time, on 5 years from date of issuance.
    
        Signed this [day] day of [month], Year.
    Director, Water Management Division, EPA, Region 4.
    
    Part I. Requirements for NPDES Permits
    
    Section A. Permit Applicability and Coverage Conditions
    
    1. Operations Covered
        These permits establish effluent limitations, prohibitions, 
    reporting requirements, and other conditions for discharges from oil 
    and gas facilities engaged in production, field exploration, drilling, 
    well completion, and well treatment operations from potential new 
    sources and existing sources.
        The permit coverage area includes Federal waters in the Gulf of 
    Mexico seaward of the 200 meter water depth for offshore Alabama and 
    Florida in the Eastern Planning Area, and seaward of the outer boundary 
    of the territorial seas for offshore Mississippi and Alabama in the 
    Central Planning Area. This permit only covers facilities located in 
    and discharging to the Federal waters listed above and does not 
    authorize discharges from facilities in or discharging to the 
    territorial sea (within 3 miles of shore) of the Gulf coastal states or 
    from facilities defined as ``coastal'' or ``onshore'' (see 40 CFR, part 
    435, subparts C and D).
    2. Operations Excluded
        Any operator who seeks to discharge drill fluids, drill cuttings or 
    produced water within 1000 meters of an area of biological concern is 
    ineligible for coverage under these general permits and must apply for 
    an individual permit.
        Any operator with leases occurring below the 26 deg. parallel which 
    are currently under moratorium are excluded from inclusion under these 
    general permits.
        No coverage will be extended under either of the new general 
    permits to non-operational leases.
    3. General Permit Applicability
        In accordance with 40 CFR 122.28(b)(3) and 122.28(c), the Regional 
    Administrator may require any person authorized by this permit to apply 
    for and obtain an individual NPDES permit when:
        (a) The discharge(s) is a significant contributor of pollution;
        (b) The discharger is not in compliance with the conditions of this 
    permit;
        (c) A change has occurred in the availability of the demonstrated 
    technology or practices for the control or abatement of pollutants 
    applicable to the point sources;
        (d) Effluent limitation guidelines are promulgated for point 
    sources covered by this permit;
        (e) A Water Quality Management Plan containing requirements 
    applicable to such point source is approved;
        (f) It is determined that the facility is located in an area of 
    biological concern.
        (g) Circumstances have changed since the time of the request to be 
    covered so that the discharger is no longer appropriately controlled 
    under the general permit, or either a temporary or permanent reduction 
    or elimination of the authorized discharge is necessary.
        The Regional Administrator may require any operator authorized by 
    this permit to apply for an individual NPDES permit only if the 
    operator has been notified in writing that a permit application is 
    required.
        Any operator authorized by this permit may request to be excluded 
    from the coverage of this general permit by applying for an individual 
    permit. The operator shall submit an application together with the 
    reasons supporting the request to the Regional Administrator no later 
    than 180 days before an activity is scheduled to commence on the lease 
    block. When an individual NPDES permit is issued to an operator 
    otherwise subject to this permit, the applicability of this permit to 
    the owner or operator is automatically terminated on the effective date 
    of the individual permit.
        A source excluded from coverage under this general permit solely 
    because it already has an individual permit may request that its 
    individual permit be revoked, and that it be covered by this general 
    permit. Upon revocation of the individual permit, this general permit 
    shall apply to the source after the notification of intent to be 
    covered is filed (see I.A.4, below).
    4. Notification Requirements (Existing Sources and New Sources)
        Written notification of intent (NOI) to be covered in accordance 
    with the general permit requirements shall state whether the permittee 
    is requesting coverage under the existing source general permit or new 
    source general permit, and shall contain the following information:
        (1) The legal name and address of the owner or operator;
        (2) The facility name and location, including the lease block 
    assigned by the Department of Interior, or if none, the name commonly 
    assigned to the lease area;
        (3) The number and type of facilities and activity proposed within 
    the lease block;
        (4) The waters into which the facility will be discharging;
        (5) The date on which the owner/operator commenced on-site 
    construction, including:
        (a) Any placement assembly or installation of facilities or 
    equipment; or
        (b) The clearing, excavation or removal of existing structures or 
    facilities;
        (6) The date on which the facility commenced exploration activities 
    at the site;
        (7) The date on which the owner/operator entered into a binding 
    contract for the purchase of facilities or
    
    [[Page 862]]
    
    equipment intended to be used in its operation within a reasonable time 
    (if applicable);
        (8) The date on which the owner/operator commenced development; and
        (9) The date on which the owner/operator commenced production.
        (10) Technical information on the characteristics of the sea bottom 
    within 1000 meters of the discharge point, including but not limited to 
    information regarding geohazards, topographical formations, live 
    bottom, and chemosynthetic communities.
        (11) MMS photo documentation survey according to most current MMS 
    guidelines (NTL 88-3 or most current revision of Photodocumentation 
    Surveys), for facilities in less than 100 meters water depth in the 
    Central Planning Area.
        All notices of intent shall be signed in accordance with 40 CFR 
    Sec. 122.22.
        EPA will act on the NOI in a reasonable period of time.
        For operating leases, the NOI shall be submitted within sixty (60) 
    days after publication of the final determination on this action. Non-
    operational facilities are not eligible for coverage under these new 
    general permits. No NOI will be accepted from either a non-operational 
    or newly acquired lease until such time as an exploration plan or 
    development production plan has been prepared for submission to EPA. 
    Operators obtaining coverage under the existing source general permit 
    for exploration activities must send a new NOI for coverage of 
    development and production activities under the new source general 
    permit sixty (60) days prior to commencing such operations. All NOI's 
    requesting coverage should be sent by certified mail to: Director, 
    Water Management Division, U.S. EPA, Region 4, Atlanta Federal Center, 
    61 Forsyth Street, S.W., Atlanta, GA 30303-3104.
        For drilling activity, the operator shall submit a Notice to Drill 
    (NTD) sixty (60) days prior to the actual move-on date. This NTD shall 
    contain: (1) the assigned NPDES general permit number assigned to the 
    lease block, (2) the latitude and longitude of the proposed discharge 
    point, (3) the water depth, and (4) the estimated length of time the 
    drilling operation will last. This NTD shall be submitted to Region 4 
    at the address above, by certified mail to: Director, Water Management 
    Division, U.S. EPA, Region 4, Atlanta Federal Center, 61 Forsyth 
    Street, S.W., Atlanta, GA 30303-3104.
        In addition, a notice of commencement of operations (NCO) is 
    required to be submitted for each of the following activities: placing 
    a production platform in the general permit coverage area (within 30 
    days prior to placement); and discharging waste water within the 
    coverage area (within 30 days prior to initiation of produced water 
    discharges). The NCO required for discharging waste water shall be 
    accompanied by the information requested in Appendix A for calculation 
    of the toxicity limitation for produced water discharges. Within sixty 
    (60) days after produced water discharge begins, the permittee shall 
    perform adequate tests to establish a bbl/day estimate to be used in 
    the Cormix model. This information must then be provided to EPA.
        All NOIs, NTDs, NCOs, and any subsequent reports required under 
    this permit shall be sent by certified mail to the following address: 
    Director, Water Management Division, U.S. EPA, Region 4, Atlanta 
    Federal Center, 61 Forsyth Street, S.W., Atlanta, GA 30303-3104.
        5. Termination of Operations
        Lease block operators shall notify the Director (at the address 
    above) within 60 (sixty) days after the permanent termination of 
    discharges from their facility.
        6. Intent To Be Covered by a Subsequent Permit
        This permit shall expire five (5) years from the effective date of 
    issuance. However, an expired general permit continues in force and 
    effect until a new general permit is issued. Lease block operators 
    authorized to discharge by this permit shall by certified mail notify 
    the Director, Water Management Division, U.S. EPA, Region 4, Atlanta 
    Federal Center, 61 Forsyth Street, S.W., Atlanta, GA 30303-3104, on or 
    before [6 months prior to the expiration date of the permit], that they 
    intend to be covered by a permit that will authorize discharge from 
    these facilities after the termination date of this permit on [month, 
    day of year].
        Permittees must submit a new NOI in accordance with the 
    requirements of this permit to remain covered under the continued 
    general permit after the expiration of this permit. Therefore, 
    facilities that have not submitted an NOI under the permit by the 
    expiration date cannot become authorized to discharge under any 
    continuation of this NPDES general permit. All NOI's from permittees 
    requesting coverage under a continued permit should be sent by 
    certified mail to: Director, Water Management Division, U.S. EPA, 
    Region 4, Atlanta Federal Center, 61 Forsyth Street, S.W., Atlanta, GA 
    30303-3104.
    
    Section B. Effluent Limitations and Monitoring Requirements
    
    1. Drilling Fluids
        The discharge of drilling fluids shall be limited and monitored by 
    the permittee as specified in both tables and below.
    
        Note: The permit prohibitions and limitations that apply to 
    drilling fluids, also apply to fluids that adhere to drill cuttings. 
    Any permit condition that applies to the drilling fluid system, 
    therefore, also applies to cuttings discharges.
    (a) Prohibitions
        Oil-Based Drilling Fluids. The discharge of oil-based drilling 
    fluids and inverse emulsion drilling fluids is prohibited.
        Oil-Contaminated Drilling Fluids. The discharge of drilling fluids 
    to which waste engine oil, cooling oil, gear oil or any lubricants 
    which have been previously used for purposes other than borehole 
    lubrication have been added, is prohibited.
        Diesel Oil. Drilling fluids to which any diesel oil has been added 
    as a lubricant or pill may not be discharged.
        No Discharge Near Areas of Biological Concern. For those facilities 
    within 1000 meters of an area of biological concern the discharge of 
    drilling fluids is not allowed.
    (b) Limitations
        Mineral Oil. Mineral oil may be used only as a lubricity additive 
    or pill. If mineral oil is added to a water-based drilling fluid, the 
    drilling fluid may not be discharged unless the 96-hr LC50 of the 
    drilling fluid is greater than 30,000 ppm SPP and it passes the static 
    sheen test for free oil.
        Cadmium and Mercury in Barite. There shall be no discharge of 
    drilling fluids to which barite has been added if such barite contains 
    mercury in excess of 1.0 mg/kg (dry weight) or cadmium in excess of 3.0 
    mg/kg (dry weight).
        The permittee shall analyze a representative sample of each supply 
    of stock barite prior to drilling each well and submit the results for 
    total mercury and cadmium in the Discharge Monitoring Report (DMR). If 
    more than one well is being drilled at a site, new analyses are not 
    required for subsequent wells, provided that no new supplies of barite 
    have been received since the previous analysis. In this case, the 
    results of the previous analysis should be used for completion of the 
    DMR.
        Alternatively, the permittee may provide certification, as 
    documented by the supplier(s), that the barite being used on the well 
    will meet the above limits. The concentration of the mercury
    
    [[Page 863]]
    
    and cadmium in the barite shall be reported on the DMR as documented by 
    the supplier.
        Analyses shall be conducted by absorption spectrophotometry (see 40 
    CFR Part 136, flame and flameless AAS) and the results expressed in mg/
    kg (dry weight).
        Toxicity. Discharged drilling fluids shall meet both a daily 
    minimum and a monthly average minimum effluent toxicity limitation of 
    at least 30,000 ppm, (v/v) of a 9:1 seawater:mud suspended particulate 
    phase (SPP) based on a 96-hour test using Mysidopsis bahia. The method 
    is published in the final effluent guidelines at 58 FR 12507. 
    Monitoring shall be performed at least once per month for both the 
    daily minimum and the monthly average minimum. In addition, an end-of-
    well sample is required (see definitions). The type of sample required 
    is a grab sample, taken from beneath the shale shaker. Results of 
    toxicity tests must be reported on the monthly DMRs. Copies of the 
    laboratory reports also must be submitted with the DMRs.
        Free Oil. No free oil shall be discharged. Monitoring shall be 
    performed prior to discharges and on each day of discharge using the 
    static (laboratory) sheen test method in accordance with the method 
    provided in Part IV.A.3, as published in the final effluent guidelines 
    (58 FR 12506). The discharge of drilling fluids that fail the static 
    sheen test is prohibited. The results of each sheen test must be 
    recorded and the number of observations of a sheen must be reported on 
    each monthly DMR.
        Maximum Discharge Rate. All facilities are subject to a maximum 
    discharge rate of 1,000 barrels per hour. Average daily discharge rates 
    must be recorded and the monthly average discharge rate reported on the 
    monthly DMR in barrels/day (BPD).
    (c) Monitoring Requirements
        In addition to the above limitations, the following monitoring and 
    reporting requirements also apply to drilling fluids discharges.
        Drilling Fluids Inventory. The permittee shall maintain a precise 
    chemical inventory of all constituents and their total volume or mass 
    added downhole for each well. Information shall be recorded but not 
    reported unless specifically requested by EPA.
        Volume. Once per month, the total monthly volume (bbl/month) of 
    discharged drilling fluids must be estimated and recorded. The volume 
    shall be reported on the monthly DMR.
        Oil Content. There is no numeric limitation on the oil content of 
    discharged drilling muds (except that muds containing any waste oil, or 
    diesel oil as a lubricity agent shall not be discharged). However, note 
    that the oil added shall not cause a violation of either the toxicity 
    or free oil limitations discussed above. The oil content of discharged 
    drilling fluids shall be determined once per day when discharging, on a 
    grab sample taken from the same mud system being observed for the 
    static sheen (free oil) test.
    2. Drill Cuttings
        The discharge of drill cuttings shall be limited and monitored by 
    the permittee as specified in both tables and below.
    
        Note: The permit prohibitions and limitations that apply to 
    drilling fluids also apply to fluids that adhere to drill cuttings. 
    Any permit condition that applies to the drilling fluid system, 
    therefore, also applies to cuttings discharges. Monitoring 
    requirements, however, may not be the same.
    (a) Prohibitions
        Cuttings from Oil-Based Drilling Fluids. Prohibitions that apply to 
    drilling fluids, set forth above in B.1(a), also apply to drill 
    cuttings. Therefore, the discharge of cuttings is prohibited when they 
    are generated while using an oil-based or invert emulsion mud.
        Cuttings from Oil Contaminated Drilling Fluids. The discharge of 
    cuttings that are generated using drilling fluids that contain waste 
    engine oil, cooling oil, gear oil or any lubricants which have been 
    previously used for purposes other than borehole lubrication is 
    prohibited.
        Cuttings generated using drilling fluids which contain diesel oil. 
    Drill cuttings generated using drilling fluids to which any diesel oil 
    has been added as a lubricant may not be discharged.
        Cuttings generated using mineral oil. The discharge of cuttings 
    generated using drilling fluids which contain mineral oil is prohibited 
    except when the mineral oil is used as a carrier fluid (transporter 
    fluid), lubricity additive, or pill.
        No Discharge Near Areas of Biological Concern. For those facilities 
    within 1000 meters of an area of biological concern discharge of 
    drilling cuttings is not allowed.
    (b) Limitations
        Mineral Oil. Limitations that apply to drilling fluids also apply 
    to drill cuttings. Therefore, if mineral oil pills or mineral oil 
    lubricity additives have been introduced to a water-based mud system, 
    cuttings may be discharged if they meet the limitations for toxicity 
    and free oil.
        Free Oil. No free oil shall be discharged. Monitoring shall be 
    performed prior to bulk discharges and on each day of discharge using 
    the static (laboratory) sheen test method in accordance with the method 
    provided in Part IV.A.3. The discharge of cuttings that fail the static 
    sheen test is prohibited. The results of each sheen test must be 
    recorded and the number of observations of a sheen must be reported on 
    each monthly DMR.
        Toxicity. Discharged cuttings generated using drilling fluids with 
    a daily minimum or a monthly average minimum 96-hour LC50 of less than 
    30,000 ppm, (v/v) of a 9:1 seawater to drilling fluid suspended 
    particulate phase (SPP) volumetric ratio using Mysidopsis bahia shall 
    not be discharged.
    (c) Monitoring Requirements
        Volume. Once per month, the monthly total discharge must be 
    estimated and recorded. The estimated volume of cuttings discharged 
    (bbl/month) shall be reported on the DMR.
    3. Produced Water
        The discharge of produced water shall be limited and monitored by 
    the permittee as specified in both tables and below.
    (a) Prohibitions
        No Discharge Near Areas of Biological Concern. For those facilities 
    within 1000 meters of an area of biological concern discharge of 
    produced water is not allowed.
    (b) Limitations
        Oil and Grease. Produced water discharges must meet both a daily 
    maximum limitation of 42 mg/l and a monthly average limitation of 29 
    mg/l for oil and grease. A grab sample must be taken at least once per 
    month. The daily maximum samples may be based on the average 
    concentration of four grab samples taken within the 24-hour period. If 
    only one sample is taken for any one month, it must meet both the daily 
    and monthly limits. If more samples are taken, they may exceed the 
    monthly average for any one day, provided that the average of all 
    samples taken meets the monthly limitation. The gravimetric method is 
    specified at 40 CFR part 136. The highest daily oil and grease 
    concentration and the monthly average concentration shall be reported 
    on the monthly DMR.
        Toxicity. Produced water discharges must meet a toxicity limitation 
    projected to be the limiting permissible
    
    [[Page 864]]
    
    concentration (0.01 x LC50) at the edge of a 100-meter mixing zone. The 
    toxicity limitation will be calculated by EPA based on each facility's 
    site-specific water column conditions and discharge configuration. The 
    methods for this determination are presented in Appendix A of this 
    permit using the Cornell Mixing Zone Expert System (CORMIX). The 
    CORMIX1 (Version 1.4), which is explained in Chapter 4, Section 4.4 of 
    the Ocean Discharge Criteria Evaluation will be used to evaluate the 
    toxicity of the produced water outfalls.
        Compliance with the toxicity limitation shall be demonstrated by 
    conducting 96-hour toxicity tests each month using Mysidopsis bahia and 
    sheepshead minnows. The method is published in ``Methods for Measuring 
    the Acute Toxicity of Effluents to Freshwater and Marine Organisms'' 
    (EPA/600/4-85/013). The results for both species shall be reported on 
    the monthly DMR. The operator shall also submit a copy of all 
    laboratory reports with the DMR.
    (b) Monitoring Requirements
        Flow. Once per month, an estimate of the total flow (bbl/month) 
    must be reported on the DMR.
    4. Deck Drainage
        The discharge of deck drainage shall be limited and monitored by 
    the permittee as specified in both tables and below.
    (a) Limitations
        Free Oil. No free oil shall be discharged. Monitoring shall be 
    performed on each day of discharge using the visual sheen test method 
    in accordance with the method provided at Part IV.A.4. The discharge of 
    deck drainage that fails the visual sheen test is prohibited. The 
    results of each sheen test must be recorded and the number of 
    observations of a sheen must be reported on each monthly DMR.
    (b) Monitoring Requirements
        Volume. Once per month, the monthly total discharge (bbls/month) 
    must be estimated and reported on the DMR.
    5. Produced Sand
        The discharge of produced sand is prohibited under this general 
    permit. Wastes must be hauled to shore for treatment and disposal.
    6. Well Treatment Fluids, Completion Fluids, and Workover Fluids
        The discharge of well treatment fluids, completion fluids, and 
    workover fluids shall be limited and monitored by the permittee as 
    specified in both tables and below.
    (a) Limitations
        Free Oil. No free oil shall be discharged. Monitoring shall be 
    performed prior to discharge and on each day of discharge using the 
    static (laboratory) sheen test method in accordance with the method 
    provided at Part IV.A.3. The discharge of well treatment, completion, 
    or workover fluids that fail the static sheen test is prohibited. The 
    results of each sheen test must be recorded and the number of 
    observations of a sheen must be reported on each monthly DMR.
        Oil and Grease. Well treatment fluids, completion fluids, and 
    workover fluids discharges must meet both a daily maximum of 42 mg/l 
    and a monthly average of 29 mg/l limitation for oil and grease. A grab 
    sample must be taken at least once per month when discharging. The 
    daily maximum concentration may be based on the average of four grab 
    samples taken within the 24-hour period. If only one sample is taken 
    for any one month, it must meet both the daily and monthly limits. If 
    more samples are taken, they may exceed the monthly average for any one 
    day, provided that the average of all samples taken meets the monthly 
    limitation. The analytical method is the gravimetric method, as 
    specified at 40 CFR part 136.
        Priority Pollutants. For well treatment fluids, completion fluids, 
    and workover fluids, the discharge of priority pollutants is prohibited 
    except in trace amounts. Information on the specific chemical 
    composition of any additives containing priority pollutants shall be 
    recorded.
    
        Note: If materials added downhole as well treatment, completion, 
    or workover fluids contain no priority pollutants, the discharge is 
    assumed not to contain priority pollutants except possibly in trace 
    amounts.
    (b) Monitoring Requirements
        Volume. Once per month, an estimate of the total volume discharged 
    (bbls/month) shall be reported on the DMR.
    7. Sanitary Waste (Facilities Continuously Manned by 10 or More 
    Persons)
        The discharge of sanitary waste shall be limited and monitored by 
    the permittee as specified in both tables and below.
    (a) Prohibitions
        Solids. No floating solids may be discharged. Observations must be 
    made once per day, during daylight in the vicinity of sanitary waste 
    outfalls, following either the morning or midday meals and at the time 
    during maximum estimated discharge. The number of days solids are 
    observed shall be recorded.
    (b) Limitations
        Residual Chlorine. Total residual chlorine is a surrogate parameter 
    for fecal coliform. Discharges of sanitary waste must contain a minimum 
    of 1 mg residual chlorine/l and shall be maintained as close to this 
    concentration as possible. The approved analytical method is Hach CN-
    66-DPD. A grab sample must be taken once per month and the 
    concentration reported.
        (Exception) Any facility which properly maintains a marine 
    sanitation device (MSD) that complies with pollution control standards 
    and regulations under Section 312 of the Act shall be deemed in 
    compliance with permit limitations for sanitary waste. The MSD shall be 
    tested annually for proper operation and the test results maintained at 
    the facility. The operator shall indicate use of an MSD on the monthly 
    DMR.
    (c) Monitoring Requirements
        Flow. Once per month, the average flow (MGD) must be estimated and 
    recorded for the flow of sanitary wastes.
    8. Sanitary Waste (Facilities Continuously Manned by 9 or Fewer Persons 
    or Intermittently by Any Number)
        The discharge of sanitary waste shall be limited and monitored by 
    the permittee as specified in both tables and below.
    (a) Prohibitions
        Solids. No floating solids may be discharged to the receiving 
    waters. An observation must be made once per day when the facility is 
    manned, during daylight in the vicinity of sanitary waste outfalls, 
    following either the morning or midday meal and at a time during 
    maximum estimated discharge. The number of days solids are observed 
    shall be recorded.
        (Exception) Any facility which properly maintains a marine 
    sanitation device (MSD) that complies with pollution control standards 
    and regulations under Section 312 of the Act shall be deemed in 
    compliance with permit limitations for sanitary waste. The MSD shall be 
    tested annually for proper operation and the test results maintained at 
    the facility. The operator shall indicate use of an MSD on the monthly 
    DMR.
    
    [[Page 865]]
    
    9. Domestic Waste
        The discharge of domestic waste shall be limited and monitored by 
    the permittee as specified in both tables and below.
    (a) Prohibitions
        Solids. No floating solids shall be discharged. In addition, food 
    waste, comminuted or not, may not be discharged within 12 nautical 
    miles from nearest land.
    (b) Limitations
        Solids. Comminuted food waste which can pass through a 25-mm mesh 
    screen (approximately 1 inch) may be discharged 12 or more nautical 
    miles from nearest land.
    (c) Monitoring Requirements
        Solids. An observation must be made during daylight in the vicinity 
    of domestic waste outfalls following either the morning or midday meal 
    and at a time during maximum estimated discharge. The number of days 
    solids are observed must be recorded.
    10. Miscellaneous Discharges
        Desalination Unit Discharge; Blowout Preventer Fluid; 
    Uncontaminated Ballast Water; Uncontaminated Bilge Water; Mud, 
    Cuttings, and Cement at the Seafloor; Uncontaminated Seawater; Boiler 
    Blowdown; Source Water and Sand; Diatomaceous Earth Filter Media.
        The discharge of miscellaneous discharges shall be limited and 
    monitored by the permittee as specified in both tables and below.
    (a) Limitations
        Free Oil. No free oil shall be discharged. Monitoring shall be 
    performed using the visual sheen test method once per day when 
    discharging on the surface of the receiving water or by use of the 
    static sheen method at the operator's option. Both tests shall be 
    conducted in accordance with the methods presented at IV.A.3 and 
    IV.A.4. Discharge is limited to those times that a visual sheen 
    observation is possible. The number of days a sheen is observed must be 
    recorded.
        (Exception) Discharge is not restricted to periods when observation 
    is possible; however, the static (laboratory) sheen test method must be 
    used during periods when observation of a sheen is not possible, such 
    as at night or during inclement conditions.
    
    Section C. Other Discharge Limitations
    
    1. Floating Solids or Visible Foam
        There shall be no discharge of floating solids or visible foam from 
    any source other than in trace amounts.
    2. Halogenated Phenol Compounds
        There shall be no discharge of halogenated phenol compounds as a 
    part of any waste streams authorized in this permit.
    3. Dispersants, Surfactants, and Detergents
        The facility operator shall minimize the discharge of dispersants, 
    surfactants, and detergents except as necessary to comply with the 
    safety requirements of the Occupational Safety and Health 
    Administration and MMS. This restriction applies to tank cleaning and 
    other operations which do not directly involve the safety of workers. 
    The restriction is imposed because detergents disperse and emulsify 
    oil, potentially increasing toxic impacts and making the detection of a 
    discharge of free oil more difficult.
    4. Rubbish, Trash, and Other Refuse
        The discharge of any solid material not authorized in the permit 
    (as described above) is prohibited.
        This permit includes limitations set forth by the U.S. Coast Guard 
    in regulations implementing Annex V of MARPOL 73/78 for domestic waste 
    disposal from all fixed or floating offshore platforms and associated 
    vessels engaged in exploration or exploitation of seabed mineral 
    resources (33 CFR 151). These limitations, as specified by Congress (33 
    U.S.C. 1901, the Act to Prevent Pollution from Ships), apply to all 
    navigable waters of the United States.
        This permit prohibits the discharge of ``garbage'' including food 
    wastes, within 12 nautical miles from nearest land. Comminuted food 
    waste (able to pass through a screen with a mesh size no larger than 25 
    mm, approx. 1 inch) may be discharged when 12 nautical miles or more 
    from land. Graywater, drainage from dishwater, shower, laundry, bath, 
    and washbasins are not considered garbage within the meaning of Annex 
    V. Incineration ash and non-plastic clinkers that can pass through a 
    25-mm mesh screen may be discharged beyond 3 miles from nearest land. 
    Otherwise, ash and non-plastic clinkers may be discharged beyond 12 
    nautical miles from nearest land.
    5. Areas of Biological Concern
        There shall be no discharge of drilling muds, drill cuttings and 
    produced water within 1000 meters of Areas of Biological Concern. If at 
    any time it is determined that a facility is located within 1000 meters 
    of an area of biological concern, the operator shall immediately cease 
    discharge from these outfalls in the area and shall file an application 
    for an individual permit as provided in 40 CFR 122.28(b)(3). The 
    operator may not resume discharging from these outfalls until an 
    individual permit has been issued.
    
    Part II. Standard Conditions for NPDES Permits
    
    Section A. Introduction and General Conditions
    
        In accordance with the provisions of 40 CFR Part 122.41, et. seq., 
    this permit incorporates by reference ALL conditions and requirements 
    applicable to NPDES permits set forth in the Clean Water Act, as 
    amended, as well as ALL applicable regulations.
    1. Duty to Comply
        The permittee must comply with all conditions of this permit. Any 
    permit noncompliance constitutes a violation of the Act and is grounds 
    for enforcement action or for requiring a permittee to apply and obtain 
    an individual NPDES permit.
    2. Penalties for Violations of Permit Conditions--33 U.S.C. 1319(c)
    (a) Criminal Penalties
        (1) Negligent Violations. The Act provides that any person who 
    negligently violates permit conditions implementing Section 301, 
    302, 306, 307, 308, 318, or 405 of the Act is subject to criminal 
    penalties of not less than $2,500 nor more than $25,000 per day of 
    violation, or by imprisonment for not more than 1 year, or both.
        (2) Knowing Violations. The Act provides that any person who 
    knowingly violates permit conditions implementing Section 301, 302, 
    306, 307, 308, 318, or 405 of the Act is subject to criminal 
    penalties of not less than $5,000 nor more than $50,000 per day of 
    violation, or by imprisonment for not more than 3 years, or both.
        (3) Knowing Endangerment. The Act provides that any person who 
    knowingly violates permit conditions implementing Section 301, 302, 
    303, 306, 307, 308, 318, or 405 of the Act and who knows at that 
    time that he is placing another person in imminent danger of death 
    or serious bodily injury is subject to a fine of not more than 
    $250,000 per day of violation for individuals or up to $1 million 
    for organizations, or by imprisonment for not more than 15 years, or 
    both.
        (4) False Statements. The Act provides that any person who 
    knowingly makes any false material statement, representation, or 
    certification in any application, record, report, plan, or other 
    document filed or required to be maintained under the Act or who 
    knowingly falsifies, tampers with, or renders inaccurate, any 
    monitoring device or method required to be maintained under the Act, 
    shall upon conviction, be punished by a fine of not more than 
    $10,000, or by imprisonment for not more than 2 years, or by both. 
    If a conviction of a person is for a violation committed after a 
    first conviction of
    
    [[Page 866]]
    
    such person under this paragraph, punishment shall be by a fine of 
    not more than $20,000 per day of violation, or by imprisonment of 
    not more than 4 years, or by both. (See Section 309(c) of the Clean 
    Water Act.)
    (b) Civil Penalties--33 U.S.C. 1319(d)
        The Act provides that any person who violates a permit condition 
    implementing Section 301, 302, 306, 307, 308, 318, or 405 of the Act is 
    subject to a civil penalty not to exceed $25,000 per day for such 
    violation. A single operational upset which leads to simultaneous 
    violations of more than one pollutant parameter shall be treated as a 
    single violation.
    (c) Administrative Penalties
        The Act at Section 309 allows that the Regional Administrator may 
    assess a Class I or Class II civil penalty for violations of Section 
    301, 302, 306, 307, 308, 318, or 405 of the Act. A Class I penalty may 
    not exceed $10,000 per violation nor shall the maximum amount exceed 
    $25,000. A Class II penalty may not exceed $10,000 per day for each day 
    during which the violation continues except that the maximum amount 
    shall not exceed $125,000. An upset that leads to violations of more 
    than one pollutant parameter will be treated as a single violation.
    3. Duty to Mitigate
        The permittee shall take all reasonable steps to minimize or 
    prevent any discharge in violation of this permit which has a 
    reasonable likelihood of adversely affecting human health or the 
    environment.
    4. Permit Flexibility
        These permits may be modified, revoked and reissued for the causes 
    set forth at 40 CFR 122.62. The permits may be terminated for the 
    following reasons (see 40 CFR 122.62):
        (a) Violation of any terms or conditions of this permit;
        (b) Obtaining this permit by misrepresentation or failure to 
    disclose fully all relevant facts;
        (c) A change in any condition that requires either a temporary or a 
    permanent reduction or elimination of the authorized discharge; or
        (d) A determination that the permitted activity endangers human 
    health or the environment and can only be regulated to acceptable 
    levels by permit modification or termination.
        The filing of a request for a permit modification, revocation and 
    reissuance, or termination, or a notification of planned changes or 
    anticipated noncompliance does not stay any permit condition.
    5. Toxic Pollutants
        Notwithstanding Part II.A.4, if any toxic effluent standard or 
    prohibition (including any schedule of compliance specified in such 
    effluent standard or prohibition) is promulgated under Section 307(a) 
    of the Act for a toxic pollutant which is present in the discharge and 
    that standard or prohibition is more stringent than any limitation on 
    the pollutant in this permit, this permit shall be modified or revoked 
    and reissued to conform to the toxic effluent standard or prohibition 
    and the permittee so notified.
        The permittee shall comply with effluent standards or prohibitions 
    established under Section 307(a) of the Act for toxic pollutants within 
    the time provided in the regulations that established those standards 
    or prohibitions, even if the permit has not yet been modified to 
    incorporate the requirement.
    6. Civil and Criminal Liability
        Except as provided in permit conditions on ``Bypassing'' and 
    ``Upsets'' (see II.B.3 and II.B.4), nothing in this permit shall be 
    construed to relieve the permittee from civil or criminal penalties for 
    noncompliance with permit conditions. Any false or misleading 
    representation or concealment of information required to be reported by 
    the provisions of the permit, the Act, or applicable CFR regulations, 
    which avoids or effectively defeats the regulatory purpose of the 
    permit may subject the permittee to criminal enforcement pursuant to 18 
    U.S.C. Section 1001.
    7. Oil and Hazardous Substance Liability
        Nothing in this permit shall be construed to preclude the 
    institution of any legal action or relieve the permittee from any 
    responsibilities, liabilities, or penalties to which the permittee is 
    or may be subject under Section 311 of the Clean Water Act.
    8. State Laws
        Nothing in this permit shall be construed to preclude the 
    institution of any legal action or relieve the permittee from any 
    responsibilities, liabilities, or penalties established pursuant to any 
    applicable State law or regulation under authority preserved by Section 
    510 of the Clean Water Act.
    9. Property Rights
        The issuance of this permit does not convey any property rights of 
    any sort, any exclusive privileges, authorize any injury to private 
    property, any invasion of personal rights, nor any infringement of 
    Federal, state, or local laws or regulations.
    10. Onshore or Offshore Construction
        This permit does not authorize or approve the construction of any 
    onshore or offshore physical structure of facilities or the undertaking 
    of any work in any waters of the United States.
    11. Severability
        The provisions of this permit are severable. If any provision of 
    this permit or the application of any provision of this permit to any 
    circumstance is held invalid, the application of such provision to 
    other circumstances, and the remainder of this permit, shall not be 
    affected thereby.
    12. Duty to Provide Information
        The permittee shall furnish to the Regional Administrator, within a 
    reasonable time, any information which the Regional Administrator may 
    request to determine whether cause exists for modifying, revoking and 
    reissuing, or terminating this permit, or to determine compliance with 
    this permit. The permittee shall also furnish to the Regional 
    Administrator upon request, copies of records required to be kept by 
    this permit.
    
    Section B. Proper Operation and Maintenance of Pollution Controls
    
    1. Proper Operation and Maintenance
        The permittee shall at all times properly operate and maintain all 
    facilities and systems of treatment and control (and related 
    appurtenances) that are installed or used by the permittee to achieve 
    compliance with this permit. Proper operation and maintenance also 
    includes adequate laboratory controls and appropriate quality assurance 
    procedures. This provision requires the operation of backup or 
    auxiliary facilities or similar systems which are installed by a 
    permittee only when the operation is necessary to achieve compliance 
    with the conditions of this permit.
    2. Need To Halt or Reduce Not a Defense
        It shall not be a defense for a permittee in an enforcement action 
    that it would have been necessary to halt or reduce the permitted 
    activity in order to maintain compliance with the conditions of this 
    permit.
    3. Bypass of Treatment Facilities
    (a) Definitions
        (1) Bypass means the intentional diversion of waste streams from 
    any portion of a treatment facility.
    
    [[Page 867]]
    
        (2) Severe property damage means substantial physical damage to 
    property, damage to the treatment facilities that causes them to become 
    inoperable, or substantial and permanent loss of natural resources that 
    can reasonably be expected to occur in the absence of a bypass. Severe 
    property damage does not mean economic loss caused by delays in 
    production.
    (b) Bypass Not Exceeding Limitations
        The permittee may allow any bypass to occur that does not cause 
    effluent limitations to be exceeded, but only if it also is for 
    essential maintenance to assure efficient operation. These bypasses are 
    not subject to the provisions of Section B.3(c) and 3(d) below.
    (c) Notice
        (1) Anticipated bypass. If the permittee knows in advance of the 
    need for a bypass, it shall submit prior notice, if possible at least 
    ten days before the date of the bypass.
        (2) Unanticipated bypass. The permittee shall, submit notice of an 
    unanticipated bypass as required in Section D.7 (24-hour reporting).
    (d) Prohibition of Bypass
        (1) Bypass is prohibited and the Regional Administrator may take 
    enforcement action against a permittee for bypass, unless:
        (a) Bypass was unavoidable to prevent loss of life, personal 
    injury, or severe property damage;
        (b) There were no feasible alternatives to the bypass, such as the 
    use of auxiliary treatment facilities, retention of untreated wastes, 
    or maintenance during normal periods of equipment downtime. This 
    condition is not satisfied if adequate back-up equipment should have 
    been installed in the exercise of reasonable engineering judgement to 
    prevent a bypass that occurred during normal periods of equipment 
    downtime or preventive maintenance; and,
        (c) The permittee submitted notices as required under Section 
    B.3(c).
        (2) The Regional Administrator may approve an anticipated bypass 
    after considering its adverse effects, if the Regional Administrator 
    determines that it will meet the three conditions listed above in 
    Section B.3(d)(1).
    4. Upset Conditions
    (a) Definition
        Upset means an exceptional incident in which there is unintentional 
    and temporary noncompliance with technology-based permit effluent 
    limitations because of factors beyond the reasonable control of the 
    permittee. An upset does not include noncompliance to the extent caused 
    by operational error, improperly designed treatment facilities, 
    inadequate treatment facilities, lack of preventive maintenance, or 
    careless or improper operation.
    (b) Effect of An Upset
        An upset constitutes an affirmative defense to an action brought 
    for noncompliance with such technology-based permit effluent 
    limitations if the requirements of Section B.4(c) are met. No 
    determination made during administrative review of claims that 
    noncompliance was caused by upset, and before an action for 
    noncompliance, is final administrative action subject to judicial 
    review.
    (c) Conditions Necessary for a Demonstration of Upset
        A permittee who wishes to establish the affirmative defense of 
    upset shall demonstrate, through properly signed, contemporaneous 
    operating logs, or other relevant evidence that:
        (1) An upset occurred and that the permittee can identify the 
    cause(s) of the upset;
        (2) The permitted facility was at the time being properly operated;
        (3) The permittee submitted notice of the upset as required by 
    Section D.7 below; and,
        (4) The permittee complied with any remedial measures required by 
    Section A.3, above.
    (d) Burden of Proof
        In any enforcement proceeding, the permittee seeking to establish 
    the occurrence of an upset has the burden of proof.
    5. Removed Substances
        Solids, sewage sludges, filter backwash, or other pollutants 
    removed in the course of treatment or control of wastewaters shall be 
    disposed of in a manner such as to prevent any pollutant from such 
    materials from entering navigable waters. Any substance specifically 
    listed within this permit may be discharged in accordance with 
    specified conditions, terms, or limitations.
    
    Section C. Monitoring and Records
    
    1. Representative Sampling
        Samples and measurements taken as required herein shall be 
    representative of the volume and nature of the monitored discharge.
    2. Discharge Rate/Flow Measurements
        Appropriate flow measurement devices and methods consistent with 
    accepted scientific practices shall be selected, maintained, and used 
    to ensure the accuracy and reliability of measurements of the volume of 
    monitored discharges. The devices shall be installed, calibrated, and 
    maintained to insure that the accuracy of the measurements is 
    consistent with the accepted capability of that type of device. Devices 
    selected shall be capable of measuring flows with a maximum deviation 
    of less than 10% from true discharge rates throughout the 
    range of expected discharge volumes.
    3. Monitoring Procedures
        Monitoring must be conducted according to test procedures approved 
    under 40 CFR Part 136, unless other test procedures have been specified 
    in this permit in Part IV, below.
    4. Penalties for Tampering
        The Clean Water Act provides that any person who falsifies, tampers 
    with, or knowingly renders inaccurate, any monitoring device or method 
    required to be maintained under this permit shall, upon conviction, be 
    punished by a fine of not more than $10,000 per violation, or 
    imprisonment for not more than 2 years, or both.
    5. Retention of Records
        The permittee shall retain records of all monitoring information, 
    including all calibration and maintenance records and all original 
    strip chart recordings for continuous monitoring instrumentation, and 
    copies of all reports required by this permit for a period of at least 
    3 years from the date of the sample, measurement, or report. This 
    period may be extended by request of the Regional Administrator at any 
    time. The operator shall maintain records at development and production 
    facilities for 3 years, wherever practicable and at a specific shore-
    based site whenever not practicable.
    6. Record Contents
        Records of monitoring information shall include:
        (a) The date, exact place, and time of sampling or measurements;
        (b) The individual(s) who performed the sampling or measurements;
        (c) The date(s) analyses were performed;
        (d) The individual(s) who performed the analyses;
        (e) The analytical techniques or methods used; and
        (f) The results of such analyses.
    
    [[Page 868]]
    
    7. Inspection and Entry
        The permittee shall allow the Regional Administrator or an 
    authorized representative, upon the presentation of credentials and 
    other documents as may be required by the law, to:
        (a) Enter upon the permittee's premises where a regulated facility 
    or activity is located or conducted, or where records must be kept 
    under the conditions of this permit;
        (b) Have access to and copy, at reasonable times, any records that 
    must be kept under the conditions of this permit;
        (c) Inspect at reasonable times any facilities, equipment 
    (including monitoring and control equipment), practices, or operations 
    regulated or required under this permit; and
        (d) Sample or monitor at reasonable times, for the purpose of 
    assuring permit compliance or as otherwise authorized by the Act, any 
    substances or parameters at any location.
    
    Section D. Reporting Requirements
    
    1. Planned Changes
        The permittee shall give notice to Regional Administrator as soon 
    as possible of any planned physical alterations or additions to the 
    permitted facility. Notice is required only when:
        (a) The alteration or addition to a facility permitted under the 
    existing source general permit may meet one of the criteria for 
    determining whether a facility is a new source in 40 CFR Part 122.29(b) 
    (58 FR 12454; final effluent guidelines for the offshore subcategory); 
    or
        (b) The alteration or addition could significantly change the 
    nature or increase the quantity of pollutants discharged. This 
    notification applies to pollutants which are subject neither to 
    effluent limitations in the permit, nor to notification requirements 
    under 40 CFR 122.42(a)(1) (48 FR 14153, April 1, 1963, as amended at 49 
    FR 38049, September 26, 1984).
    2. Anticipated Noncompliance
        The permittee shall give advance notice to the Regional 
    Administrator of any planned changes in the permitted facility or 
    activity which may result in noncompliance with permit requirements.
    3. Transfers
        This permit is not transferable to any person. Any new owner or 
    operator shall submit a notice of intent to be covered under this 
    general permit according to procedures presented at Part I.A.3.
    4. Monitoring Reports
        See Part III.A of this permit.
    5. Additional Monitoring by the Permittee
        If the permittee monitors any pollutant more frequently than 
    required by this permit, using test procedures approved under 40 CFR 
    Part 136 or as specified in this permit, the results of this monitoring 
    shall be included in the calculation and reporting of the data 
    submitted in the DMR. Such increased monitoring frequency also shall be 
    indicated on the DMR.
    6. Averaging of Measurements
        Calculations for all limitations which require averaging of 
    measurements shall utilize an arithmetic mean unless otherwise 
    specified by the Regional Administrator in the permit.
    7. Twenty-Four Hour Reporting
        The permittee shall report any noncompliance which may endanger 
    health or the environment (this includes any spill that requires 
    reporting to the state regulatory authority). Information shall be 
    provided orally within 24 hours from the time the permittee becomes 
    aware of the circumstances. A written submission shall be provided 
    within 5 days of the time the permittee becomes aware of the 
    circumstances. The written submission shall contain a description of 
    the noncompliance and its cause; the period of noncompliance including 
    exact dates and times, and if the noncompliance has not been corrected, 
    the anticipated time it is expected to continue; and, steps taken or 
    planned to reduce, eliminate, and prevent recurrence of the 
    noncompliance. The director may waive the written report on a case-by-
    case basis if the oral report has been received within 24 hours.
        The following shall be included as information which must be 
    reported within 24 hours:
        (a) Any unanticipated bypass which exceeds any effluent limitation 
    in the permit;
        (b) Any upset which exceeds any effluent limitation in the permit;
        (c) Violations of a maximum daily discharge limitation for any of 
    the pollutants listed by the Director in Part II of the permit to be 
    reported within 24 hours.
        The reports should be made to Region 4 by telephone at (404) 562-
    9746. The Regional Administrator may waive the written report on a 
    case-by-case basis if the oral report has been received within 24 
    hours.
    8. Other Noncompliance
        The permittee shall report all instances of noncompliance not 
    reported under Part II.D.7 at the time monitoring reports are 
    submitted. The reports shall contain the information listed at II.D.7.
    9. Other Information
        When the permittee becomes aware that it failed to submit any 
    relevant facts in a permit application, or submitted incorrect 
    information in a permit application or in any report to the Regional 
    Administrator, it shall promptly submit such facts or information.
    10. Changes in Discharges of Toxic Substances
        For any toxic pollutant that is not limited in this permit, either 
    as an additive itself or as a component in an additive formulation, the 
    permittee shall notify the Regional Administrator as soon as he knows 
    or has reason to believe that:
        (a) Any activity has occurred or will occur which would result in 
    the discharge of such toxic pollutants on a routine or frequent basis, 
    if that discharge will exceed the highest of the ``notification 
    levels'' described at 40 CFR 122.42(a)(1)(i) and (ii);
        (b) Any activity has occurred or will occur which would result in 
    any discharge of such toxic pollutants on a non-routine or infrequent 
    basis, if that discharge will exceed the highest of the ``notification 
    levels'' described at 40 CFR 122.42(a)(2)(i) an (ii).
    11. Duty to Reapply
        If the permittee wishes to continue an activity regulated by this 
    permit after the expiration date of this permit, the permittee must 
    submit an NOI to be covered or must apply for a new permit. 
    Continuation of expiring permits shall be governed by regulations at 40 
    CFR Part 122.6 and any subsequent amendments.
    12. Signatory Requirements
        All NOIs, applications, reports, or information submitted to the 
    Director shall be signed and certified as required at 40 CFR 122.22.
        (a) All permit applications shall be signed as follows:
        (1) For a corporation: By a responsible corporate officer. For the 
    purpose of this section, a responsible corporate officer means:
        (i) A president, secretary, treasurer, or vice-president of the 
    corporation in charge of a principal business function, or any other 
    person who performs
    
    [[Page 869]]
    
    similar policy or decision making functions for the corporation; or,
        (ii) The manager of one or more manufacturing, production, or 
    operating facilities employing more than 250 persons or having gross 
    annual sales or expenditures exceeding $25 million (in second-quarter 
    1980 dollars), if authority to sign documents has been assigned or 
    delegated to the manager in accordance with corporate procedures.
        (2) For a partnership or sole proprietorship--by a general partner 
    or the proprietor, respectively.
        (b) Authorized Representative. All reports required by the permit 
    and other information requested by the Regional Administrator shall be 
    signed by a person described above or by a duly authorized 
    representative of that person. A person is a duly authorized 
    representative only if:
        (1) The authorization is made in writing by a person described 
    above;
        (2) The authorization specifies either an individual or a position 
    having responsibility for the overall operation of the regulated 
    facility or activity, such as the position of plant manager, operator 
    of a well or a well field, superintendent, or position of equivalent 
    responsibility, or an individual or position having overall 
    responsibility for environmental matters for the company. A duly 
    authorized representative may thus be either a named individual or an 
    individual occupying a named position; and,
        (3) The written authorization is submitted to the Regional 
    Administrator.
        (c) Changes to Authorization. If an authorization under paragraph 
    (b) of this section is no longer accurate because a different 
    individual or position has responsibility for the overall operation of 
    the facility, a new authorization satisfying the requirements of 
    paragraph (b) of this section must be submitted to the Director prior 
    to or together with any reports, information, or application to be 
    signed by an authorized representative.
        (d) Certification. Any person signing a document under this section 
    shall make the following certification: ``I certify under penalty of 
    law that this document and all attachments were prepared under my 
    direction or supervision in accordance with a system designed to assure 
    that qualified personnel properly gather and evaluate the information 
    submitted. Based on my inquiry of the person or persons who manage the 
    system, or those persons directly responsible for gathering the 
    information, the information submitted is, to the best of my knowledge 
    and belief, true, accurate, and complete. I am aware that there are 
    significant penalties for submitting false information, including the 
    possibility of fine and imprisonment for knowing violations.''
    13. Availability of Reports
        Except for data determined to be confidential under 40 CFR Part 2, 
    all reports prepared in accordance with the terms of this permit shall 
    be available for public inspection at the Regional Office. As required 
    by the Act, the name and address of any permit applicant or permittee, 
    permit applications, permits, and effluent data shall not be considered 
    confidential.
    
    Part III. Monitoring Reports and Permit Modification
    
    Section A. Monitoring Reports
    
        The operator of each lease block shall be responsible for 
    submitting monitoring results for each facility within each lease 
    block. If there is more than one facility in each lease block 
    (platform, drilling ship, semi-submersible), the discharge shall be 
    designated in the following manner: 101 for the first facility; 201 for 
    the second facility; 301 for the third facility, etc.
        Monitoring results obtained for each month shall be summarized for 
    that month and reported on a Discharge Monitoring Report (DMR) form 
    (EPA No. 3320-1), postmarked no later than the 28th day of the month 
    following the completed calendar month. (For example, data for January 
    shall be submitted by February 28.) Signed copies of these and all 
    other reports required by Part II.D shall be submitted to the following 
    address:
    
    Director, Water Management Division, Clean Water Act Enforcement 
    Section, U.S. EPA, Region 4, Atlanta Federal Center 61 Forsyth Street, 
    S.W., Atlanta, GA 30303-3104
    
        All laboratory reports submitted with DMRs should clearly indicate 
    the permit number, outfall number, and any other identification 
    information necessary to associate the report with the correct 
    facility, waste stream, and outfall.
        If no discharge occurs during the reporting period, sampling 
    requirements of this permit do not apply. The statement ``No 
    Discharge'' shall be written on the DMR form. If, during the term of 
    this permit, the facility ceases discharge to surface waters, the 
    Regional Director shall be notified immediately upon cessation of 
    discharge. This notification shall be in writing.
    
    Section B. Permit Modification
    
        This permit shall be modified, or alternatively, revoked and 
    reissued, to comply with any applicable effluent standard or 
    limitation, or sludge disposal requirement issued or approved under 
    sections 301(b)(2)(C) and (D), 307(a)(2), and 405(d)(2)(D) of the Act, 
    as amended, if the effluent standard or limitation, or sludge disposal 
    requirement so issued or approved:
        (a) Contains different conditions or is otherwise more stringent 
    than any conditions in the permit; or
        (b) Controls any pollutant or disposal method not addressed in the 
    permit.
        The permit as modified or reissued under this paragraph shall also 
    contain any other requirements of the Act then applicable.
    
    Part IV. Test Procedures and Definitions
    
    Section A. Test Procedures
    
    1. Samples of Wastes
        If requested, the permittee shall provide EPA with a sample of any 
    waste in a manner specified by the Agency.
    2. Drilling Fluids Toxicity Test
        The approved sampling and test methods for permit compliance are 
    provided in the final effluent guidelines published at 58 FR 12507 on 
    March 4, 1993 as Appendix 2 to Subpart A of Part 435.
    3. Static (Laboratory) Sheen Test
        The approved sampling and test methods for permit compliance are 
    provided in the final effluent guidelines published at 58 FR 12506 on 
    March 4, 1993 as Appendix 1 to Subpart A.
    4. Visual Sheen Test
        The visual sheen test is used to detect free oil by observing the 
    surface of the receiving water for the presence of a sheen while 
    discharging. A sheen is defined as a ``silvery'' or ``metallic'' sheen, 
    gloss, or increased reflectivity; visual color; iridescence; or oil 
    slick on the surface (see 58 FR 12507). The operator must conduct a 
    visual sheen test only at times when a sheen could be observed. This 
    restriction eliminates observations at night or when atmospheric or 
    surface conditions prohibit the observer from detecting a sheen (e.g., 
    during rain or rough seas, etc.). Certain discharges can only occur if 
    a visual sheen test can be conducted.
        The observer must be positioned on the rig or platform, relative to 
    both the discharge point and current flow at the time of discharge, 
    such that the observer can detect a sheen should it surface down 
    current from the discharge. For discharges that have been occurring for 
    at least 15 minutes previously,
    
    [[Page 870]]
    
    observations may be made any time thereafter. For discharges of less 
    than 15 minutes duration, observations must be made both during 
    discharge and 5 minutes after discharge has ceased.
    5. Produced Water Acute Toxicity Test
        The method for determining the 96-hour LC50 for effluents is 
    published in ``Methods for Measuring the Acute Toxicity of Effluents to 
    Freshwater and Marine Organisms'' (EPA/600/4-85/013). The species to be 
    used for compliance testing for this permit are Mysidopsis bahia and 
    sheepshead minnows (Cyprinodon variegatus).
    
    Section B. Definitions
    
        1. Act means the Clean Water Act (CWA), as amended (33 U.S.C. 1251 
    et seq).
        2. Administrator means the Administrator of EPA, Region 4, or an 
    authorized representative.
        3. Areas of Biological Concern for waters within the territorial 
    seas (shoreline to 3-miles offshore) are those defined as ``no activity 
    zones'' for biological reasons by the states of Alabama, Florida or 
    Mississippi. For offshore waters seaward of three miles, areas of 
    biological concern include ``no activity zones'' defined by the 
    Department of the Interior (DOI) for biological reasons, or identified 
    by EPA in consultation with the DOI, the states, or other interested 
    federal agencies, as containing biological communities, features or 
    functions that are potentially sensitive to discharges associated with 
    the oil and gas industry. Areas of Biological Concern include, but are 
    not limited to, the following: Southwest Rock (30 deg.06.1' N, 
    88 deg.12.3' W), Southeast Banks (30 deg.00.9' N; 87 deg.57.1' W); 17 
    Fathom Hole (29 deg.55.6' N 88 deg.03.4' W) and lease blocks with 
    Pinnacle Trend Features. These areas are geographically and in greater 
    detail in Appendix B. EPA may, from time to time, identify additional 
    Areas of Biological Concern.
        4. Applicable Effluent Standards and Limitations means all state 
    and Federal effluent standards and limitations to which a discharge is 
    subject under the Act, including, but not limited to, effluent 
    limitations, standards of performance, toxic effluent standards and 
    prohibitions, and pretreatment standards.
        5. Average Daily Discharge Limitation means the highest allowable 
    average of discharges over a 24-hour period, calculated as the sum of 
    all discharges or concentrations measured divided by the number of 
    discharges or concentrations measured that day.
        6. Average Monthly Discharge Limitation means the highest allowable 
    average of ``daily discharges'' over a calendar month, calculated as 
    the sum of all ``daily discharges'' measured during a calendar month 
    divided by the number of discharges measured that month. The limitation 
    may be the average of discharge rates or concentrations.
        7. Batch or Bulk Discharge is any discharge of a discrete volume or 
    mass of effluent from a pit, tank, or similar container that occurs on 
    a one-time, infrequent, or irregular basis.
        8. Blowout-Out Preventer Control Fluid means fluid used to actuate 
    the hydraulic equipment on the blow-out preventer or subsea production 
    wellhead assembly.
        9. Boiler Blowdown means discharges from boilers necessary to 
    minimize solids build-up in the boilers, including vents from boilers 
    and other heating systems.
        10. Bulk Discharge means any discharge of a discrete volume or mass 
    of effluent from a pit tank or similar container that occurs on a one-
    time, infrequent, or irregular basis.
        11. Bypass means the intentional diversion of waste streams from 
    any portion of a treatment facility.
        12. Clinkers are small lumps of residual material left after 
    incineration.
        13. Completion Fluids are salt solutions, weighted brines, polymers 
    and various additives used to prevent damage to the wellbore during 
    operations which prepare the drilled well for hydrocarbon production. 
    These fluids move into the formation and return to the surface as a 
    slug with the produced water. Drilling muds remaining in the wellbore 
    during logging, casing, and cementing operations or during temporary 
    abandonment of the well are not considered completion fluids and are 
    regulated by drilling fluids requirements.
        14. Daily Average Discharge (also known as monthly average) 
    limitations means the highest allowable average daily discharge(s) over 
    a calendar month, calculated as the sum of all daily discharge(s) 
    measured during a calendar month divided by the number of daily 
    discharge(s) measured during that month.
        15. Daily Discharge means the discharge of a pollutant measured 
    during a calendar day or any 24-hour period that reasonably represents 
    the calendar day for purposes of sampling. For pollutants with 
    limitations expressed in terms of mass, the daily discharge is 
    calculated as the total mass of the pollutant or waste stream 
    discharged over the sampling day. For pollutants with limitations 
    expressed in other units of measurement, the daily discharge is 
    calculated as the average measurement of the pollutant over the 
    sampling day. Daily discharge determination of concentration made using 
    a composite sample shall be the concentration of the composite sample. 
    When grab samples are used, the daily discharge determination of 
    concentration shall be the average (weighted by flow value) of all 
    samples collected during that sampling day.
        16. Daily Maximum Discharge Limitations are the highest allowable 
    discharge rate or concentration measured during a calendar day.
        17. Deck Drainage is all waste resulting from platform washings, 
    deck washings, deck area spills, equipment washings, rainwater, and 
    runoff from curbs, gutters, and drains, including drip pans and wash 
    areas.
        18. Desalination Unit Discharge means waste water associated with 
    the process of creating freshwater from seawater.
        19. Development Drilling means the drilling of wells required to 
    efficiently produce a hydrocarbon formation or formations.
        20. Diatomaceous Earth Filter Media is the filter media used to 
    filter seawater or other authorized completion fluids and subsequently 
    washed from the filter.
        21. Diesel Oil is the distillate fuel oil typically used in 
    conventional oil-based drilling fluids, which contains a number of 
    toxic pollutants. For the purpose of any particular operation under 
    this permit, diesel oil shall refer to the fuel oil present on the 
    facility.
        22. Domestic Waste is the discharge from galleys, sinks, showers, 
    safety showers, eye wash stations, hand washing stations, fish cleaning 
    stations, and laundries.
        23. Drill Cuttings are particles generated by drilling into the 
    subsurface geological formations including cured cement carried to the 
    surface with the drilling fluid.
        24. Drilling Fluids are any fluids sent down the hole, including 
    drilling muds and any specialty products, from the time a well is begun 
    until final cessation of drilling in that hole.
        25. End of Well Sample means the sample taken after the final log 
    run is completed and prior to bulk discharge.
        26. Excess Cement Slurry means the excess mixed cement, including 
    additives and wastes from equipment washdown after a cementing 
    operation.
        27. Existing Sources are facilities conducting exploration 
    activities and those that have commenced development or production 
    activities that were permitted as of the effective
    
    [[Page 871]]
    
    date of the Offshore Guidelines (March 4, 1993).
        28. Free Oil is oil that causes a sheen, streak, or slick on the 
    surface of the test container or receiving water.
        29. Garbage means all kinds of victual, domestic, and operational 
    waste ``generated during the normal operation of the ship and liable to 
    be disposed of continuously or periodically'' (see MARPOL 73/78 
    regulations).
        30. Grab Sample means an individual sample collected in less than 
    15 minutes.
        31. Graywater is drainage from dishwater, shower, laundry, bath, 
    and washbasin drains and does not include drainage from toilets, 
    urinals, hospitals, and drainage from cargo areas (see MARPOL 73/78 
    regulations).
        32. Inverse Emulsion Drilling Fluids are oil-based drilling fluids 
    which also contain large amounts of water.
        33. Live Bottom Areas are those areas that contain biological 
    assemblages consisting of such sessile invertebrates as sea fans, sea 
    whips, hydroids, anemones, ascideians sponges, bryozoans, seagrasses, 
    or corals living upon and attached to naturally occurring hard or rocky 
    formations with fishes and other fauna.
        34. Maximum Hourly Rate is the greatest number of barrels of 
    drilling fluids discharged within one hour, expressed as barrels per 
    hour.
        35. Muds, Cuttings, and Cement at the Seafloor means discharges 
    that occur at the seafloor prior to installation of the marine riser 
    and during marine riser disconnect, well abandonment, and plugging 
    operations.
        36. National Pollutant Discharge Elimination System (NPDES) means 
    the national program for issuing, modifying, revoking and reissuing, 
    terminating, monitoring, and enforcing permits, and imposing and 
    enforcing pretreatment requirements under sections 307, 318, 402, 403, 
    and 405 of the Act.
        37. New Source means any facility or activity of this subcategory 
    that meets the definition of ``new source'' under 40 CFR 122.2 and 
    meets the criteria for determination of new sources under 40 CFR 
    122.29(b) applied consistently with all of the following defintions: 
    (i) The term water area as used in the term ``site'' in 40 CFR 122.29 
    and 122.2 shall mean the water area and ocean floor beneath any 
    exploratory, development, or production facility where such facility is 
    conducting its exploratory, development or production activities, (ii) 
    the term significant site preparation work as used in 40 CFR 122.29 
    shall mean the process of surveying, clearing, or preparing an area of 
    the ocean floor for the purpose of constructing or placing a 
    development or production facility on or over the site.
        38. No Activity Zones include those areas identified by MMS where 
    no structures, drilling rigs, or pipelines will be allowed. These zones 
    are identified as lease stipulations in U.S. Department of the 
    Interior, MMS, August 1990, Environmental Impact Statement for Sales 
    131, 135, and 137 Western, Central, and Eastern Gulf of Mexico. 
    Additional no activity zones may be identified by MMS during the life 
    of this permit, and by the States of Alabama, Mississippi and Florida 
    within their territorial waters (up to 3 miles offshore) where no 
    structures, drilling rigs, or pipelines will be allowed.
        39. No Discharge Areas are areas specified by EPA where discharge 
    of pollutants may not occur.
        40. Non-Operational Leases are those leases on which no discharge 
    has taken place within 2 years prior to the effective date of the new 
    general permits.
        41. Operating Facilities are leases on which a discharge has taken 
    place within 2 years of the effective date of the new general permits.
        42. Packer Fluids are low solids fluids between the packer, 
    production string, and well casing. They are considered to be workover 
    fluids.
        43. Priority Pollutants are the 126 chemicals or elements 
    identified by EPA, pursuant to section 307 of the Clean Water Act and 
    40 CFR 401.15.
        44. Produced Sand is sand and other solids removed from the 
    produced waters. Produced sand also includes desander discharge from 
    produced water waste stream and blowdown of water phase from produced 
    water treating systems.
        45. Produced Water is water and particulate matter associated with 
    oil and gas producing formations. Produced water includes small volumes 
    of treating chemicals that return to the surface with the produced 
    fluids and pass through the produced water treating system.
        46. Sanitary Waste means human body waste discharged from toilets 
    and urinals.
        47. Severe Property Damage means substantial physical damage to 
    property, damage to the treatment facilities which cause them to become 
    inoperable, or substantial and permanent loss of natural resources 
    which can reasonably be expected to occur in the absence of a bypass. 
    Severe property damage does not mean economic loss caused by delays in 
    production.
        48. Sheen means a silvery or metallic sheen, gloss, or increased 
    reflectivity; visual color; iridescence; or oil slick on the water 
    surface.
        49. Source Water and Sand are the water and entrained solids 
    brought to the surface from non-hydrocarbon bearing formations for the 
    purpose of pressure maintenance or secondary recovery.
        50. Spotting means the process of adding a lubricant (spot) 
    downhole to free stuck pipe.
        51. Territorial Seas means the belt of the seas measured from the 
    line of ordinary low water along that portion of the coast which is in 
    direct contact with the open sea and the line marking the seaward limit 
    of inland waters, and extending seaward a distance of three miles.
        52. Trace Amounts means that if materials added downhole as well 
    treatment, completion, or workover fluids do not contain priority 
    pollutants then the discharge is assumed not to contain priority 
    pollutants except possibly in trace amounts.
        53. Uncontaminated Ballast/Bilge water means seawater added or 
    removed to maintain proper draft that does not come in contact with 
    surfaces that may cause contamination.
        54. Uncontaminated Seawater means seawater that is returned to the 
    sea without the addition of chemicals. Included are (1) discharges of 
    excess seawater that permit the continuous operation of fire control 
    and utility lift pumps, (2) excess seawater from pressure maintenance 
    and secondary recovery projects, (3) water released during the training 
    and testing of personnel in fire protection, (4) seawater used to 
    pressure test piping, and (5) once through non-contact cooling water.
        55. Upset means an exceptional incident in which there is 
    unintentional and temporary noncompliance with technology-based permit 
    effluent limitations because of factors beyond the reasonable control 
    of the permittee. An upset does not include noncompliance to the extent 
    caused by operational error, improperly designed treatment facilities, 
    inadequate treatment facilities, lack of preventive maintenance, or 
    careless or improper operation.
        56. Well treatment fluids are any fluid used to restore or improve 
    productivity by chemically or physically altering hydrocarbon-bearing 
    strata after a well has been drilled. These fluids move into the 
    formation and return to the surface as a slug with the produced water. 
    Stimulation fluids include substances such as acids, solvents, and 
    propping agents.
        57. Workover fluids are salt solutions, weighted brines, polymers, 
    and other specialty additives used in a producing well to allow safe 
    repair and
    
    [[Page 872]]
    
    maintenance or abandonment procedures. High solids drilling fluids used 
    during workover operations are not considered workover fluids by 
    definition and therefore must meet drilling fluid effluent limitations 
    before discharge may occur. Packer fluids, low solids fluids between 
    the packer, production string, and well casing are considered to be 
    workover fluids and must meet only the effluent requirements imposed on 
    workover fluids.
        58. The term MGD means million gallons per day.
        59. The term mg/l means milligrams per liter or parts per million 
    (ppm).
        60. The term gu/l means micrograms per liter or part per billion 
    (ppb).
    
    Existing Sources
    
                  Table 2.--Effluent Limitations, Prohibitions, and Monitoring Requirements for the Eastern Gulf of Mexico NPDES General Permit             
    --------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                Monitoring requirement                      
                                          Regulated & monitored   Discharge limitation/ --------------------------------------------------------------------
                 Discharge                discharge  parameter         prohibition            Measurement                                Recorded/reported  
                                                                                               frequency          Sample type/method           value        
    --------------------------------------------------------------------------------------------------------------------------------------------------------
    Drilling Fluids....................  Oil-based Drilling      No discharge..........                                                                     
                                          Fluids.                                                                                                           
                                         Oil-contaminated        No discharge..........                                                                     
                                          Drilling Fluids.                                                                                                  
                                         Drilling Fluids to      No discharge..........                                                                     
                                          Which Diesel Oil has                                                                                              
                                          been Added.                                                                                                       
                                         Mercury and Cadmium in  No discharge of         Once per new source    Flame and flameless    mgHg and mg Cd/kg in 
                                          Barite.                 drilling fluids if      of barite used.        AAS..                  stock barite.       
                                                                  added barite contains                                                                     
                                                                  Hg in excess of 1.0                                                                       
                                                                  mg/kg or Cd in excess                                                                     
                                                                  of 3.0 mg/kg (dry wt).                                                                    
                                         Toxicity a............  30,000 ppm daily        Once/month Once/end    Grab/96-hr LC50 using  Minimum LC50 of tests
                                                                  minimum.                of well b              Mysidopsis bahia;      performed and       
                                                                 30,000 ppm monthly      Once/month.             Method at 58 FR        monthly average     
                                                                  average minimum.                               12507.                 LC50.               
                                         Free Oil..............  No free oil...........  Once/day prior to      Static sheen; Method   Number of days sheen 
                                                                                          discharge.             at 58 FR 12506.        observed.           
                                         Maximum Discharge Rate  1,000 barrels/hr......  Once/day.............  Estimate.............  Max. hourly rate in  
                                                                                                                                        bbl/hr.             
                                         Mineral Oil...........  Mineral oil may be                                                                         
                                                                  used only as a                                                                            
                                                                  carrier fluid,                                                                            
                                                                  lubricity additive,                                                                       
                                                                  or pill.                                                                                  
                                         Drilling Fluids         Record................  Once/well............  Inventory............  Chemical             
                                          Inventory.                                                                                    constituents.       
                                         Volume................  Report................  Once/month...........  Estimate.............  Monthly total in bbl/
                                                                                                                                        month.              
                                         Within 1000 Meters of   No discharge..........                                                                     
                                          an Areas of                                                                                                       
                                          Biological Concern                                                                                                
                                          (ABC).                                                                                                            
    Drill Cuttings.....................                                                                                                                     
    (4) Note: Drill cuttings are                                                                                                                            
     subject to the same limitations/                                                                                                                       
     prohibitions as drilling fluids                                                                                                                        
     except Maximum Discharge Rate.                                                                                                                         
                                         Free Oil..............  No free oil...........  Once/day prior to      Static sheen; Method   Number of days sheen 
                                                                                          discharge.             at 58 FR 12506.        observed.           
                                         Volume................  Report................  Once/month...........  Estimate.............  Monthly total in bbl/
                                                                                                                                        month.              
    Produced Water.....................  Oil and Grease........  42 mg/l daily maximum   Once/month c.........  Grab/Gravimetric.....  Daily max. and       
                                                                  and 29 mg/l monthly                                                   monthly avg.        
                                                                  average.                                                                                  
                                         Toxicity..............  Acute toxicity (LC50);  Once/month...........  Grab/96-hour LC50      Minimum LC50 for both
                                                                  critical dilution as                           using Mysidopsis       species and full    
                                                                  specified by the                               bahia and sheepshead   laboratory report.  
                                                                  requirements at Part                           minnows (Method in                         
                                                                  I.B.3(a) and Appendix                          EPA/600/4-85/013)..                        
                                                                  A of this permit..                                                                        
                                         Flow (bbl/month)......  ......................  Once/month...........  Estimate.............  Monthly rate.        
                                         Within 1000 meters of   No discharge..........                                                                     
                                          an Area of Biological                                                                                             
                                          Concern (ABC).                                                                                                    
    Deck Drainage......................  Free Oil..............  No free oil...........  Once/day when          Visual sheen.........  Number of days sheen 
                                                                                          discharging d.                                observed.           
                                         Volume (bbl/month)....  ......................  Once/month...........  Estimate.............  Monthly total.       
    Produced Sand......................  No Discharge..........                                                                                             
    
    [[Page 873]]
    
                                                                                                                                                            
    Well Treatment, Completion, and      Free Oil..............  No free oil...........  Once/day when          Static sheen.........  Number of days sheen 
     Workover Fluids (includes packer    Oil and Grease........  42 mg/l daily maximum    discharging.          Grab/Gravimetric.....   observed.           
     fluids) e.                                                   and 29 mg/l monthly    Once/month...........                         Daily max. and       
                                                                  average.                                                              monthly avg.        
                                         Priority Pollutants...  No priority pollutants  .....................  Monitor added                               
                                                                                                                 materials.                                 
                                         Volume (bbl/month)....  ......................  Once/month...........  Estimate.............  Monthly total.       
    Sanitary Waste (Continuously manned  Solids................  No floating solids....  Once/day, in daylight  Observation..........  Number of days solids
     by 10 or more persons) f.           Residual Chlorine.....  At least (but as close  Once/month...........  Grab/Hach CN-66-DPD..   observed            
                                         Flow (MGD)............   to) 1 mg/l.            Once/month...........  Estimate.............                       
                                                                                                                                       Concentration        
    Sanitary Waste (Continuously manned  Solids................  No floating solids....  Once/day, in daylight  Observation..........  Number of days solids
     by 9 or fewer persons or                                                                                                           observed.           
     intermittently by any) f.                                                                                                                              
    Domestic Waste.....................  Solids................  No floating solids; no  Once/day following     Observation..........  Number of days solids
                                                                  food waste within 12    morning or midday                             observed.           
                                                                  miles of land;          meal at time of                                                   
                                                                  comminuted food waste   maximum expected                                                  
                                                                  smaller than 25-mm      discharge.                                                        
                                                                  beyond 12 miles.                                                                          
    Miscellaneous Discharges--           Free Oil..............  No free oil...........  Once/day when          Visual sheen.........  Number of days sheen 
     Desalination Unit, Blowout                                                           discharging.                                  observed.           
     Preventer, Fluid, Uncontaminated                                                                                                                       
     Ballast/Bilge Water, Mud,                                                                                                                              
     Cuttings, and Cement at the                                                                                                                            
     Seafloor, Uncontaminated Seawater,                                                                                                                     
     Boiler Blowdown, Source Water and                                                                                                                      
     Sand, Diatomaceous Earth Filter                                                                                                                        
     Media.                                                                                                                                                 
    --------------------------------------------------------------------------------------------------------------------------------------------------------
    a Toxicity test to be conducted using suspended particulate phase (SPP) of a 9:1 seawater:mud dilution. The sample shall be taken beneath the shale     
      shaker, or if there are no returns across the shaker, the sample must be taken from a location that is characteristic of the overall mud system to be 
      discharged.                                                                                                                                           
    b Sample shall be taken after the final log run is completed and prior to bulk discharge.                                                               
    c The daily maximum concentration may be based on the average of up to four grab sample results in the 24 hour period.                                  
    d When discharging and facility is manned. Monitoring shall be accomplished during times when observation of a visual sheen on the surface of the       
      receiving water is possible in the vicinity of the discharge.                                                                                         
    e No discharge of priority pollutants except in trace amounts. Information on the specific chemical composition shall be recorded but not reported      
      unless requested by EPA.                                                                                                                              
    f Any facility that properly operates and maintains a marine sanitation device (MSD) that complies with pollution control standards and regulations     
      under Section 312 of the Act shall be deemed to be in compliance with permit limitations for sanitary waste. The MSD shall be tested yearly for proper
      operation and test results maintained at the facility.                                                                                                
    
    New Sources
    
                  Table 3.--Effluent Limitations, Prohibitions, and Monitoring Requirements for the Eastern Gulf of Mexico NPDES General Permit             
    --------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                Monitoring Requirement                      
                                          Regulated & monitored   Discharge limitation/ --------------------------------------------------------------------
                 Discharge                discharge  parameter         prohibition            Measurement                                Recorded/reported  
                                                                                               frequency          Sample type/method           value        
    --------------------------------------------------------------------------------------------------------------------------------------------------------
    Drilling Fluids....................  Oil-based Drilling      No discharge..........                                                                     
                                          Fluids.                                                                                                           
    
    [[Page 874]]
    
                                                                                                                                                            
                                         Oil-contaminated        No discharge..........                                                                     
                                          Drilling Fluids.                                                                                                  
                                         Drilling Fluids to      No discharge..........                                                                     
                                          Which Diesel Oil has                                                                                              
                                          been Added.                                                                                                       
                                         Mercury and Cadmium in  No discharge of         Once per new source    Flame and flameless    mg Hg and mg Cd/kg in
                                          Barite.                 drilling fluids if      of barite used.        AAS.                   stock barite.       
                                                                  added barite contains                                                                     
                                                                  Hg in excess of 1.0                                                                       
                                                                  mg/kg or Cd in excess                                                                     
                                                                  of 3.0 mg/kg (dry wt).                                                                    
                                         Toxicity a............  30,000 ppm daily        Once/month Once/end    Grab/96-hr LC50 using  Minimum LC50 of tests
                                                                  minimum.                of well b.             Mysidopsis bahia;      performed and       
                                                                 30,000 ppm monthly      Once/month...........   Method at 58 FR        monthly average LC50
                                                                  average minimum.                               12507.                                     
                                         Free Oil..............  No free oil...........  Once/day prior to      Static sheen; Method   Number of days sheen 
                                                                                          discharge.             at 58 FR 12506.        observed.           
                                         Maximum Discharge Rate  1,000 barrels/hr......  Once/day.............  Estimate.............  Max. hourly rate in  
                                                                                                                                        bbl/hr.             
                                         Mineral Oil...........  Mineral oil may be                                                                         
                                                                  used only as a                                                                            
                                                                  carrier fluid,                                                                            
                                                                  lubricity additive,                                                                       
                                                                  or pill.                                                                                  
                                         Drilling Fluids         Record................  Once/well............  Inventory............  Chemical constituents
                                          Inventory.                                                                                                        
                                         Volume................  Report................  Once/month...........  Estimate.............  Monthly total in bbl/
                                                                                                                                        month               
                                         Within 1000 Meters of   No discharge..........                                                                     
                                          an Areas of                                                                                                       
                                          Biological Concern                                                                                                
                                          (ABC).                                                                                                            
    Drill Cuttings                                                                                                                                          
    (4) Note: Drill cuttings are                                                                                                                            
     subject to the same limitations/                                                                                                                       
     prohibitions as drilling fluids                                                                                                                        
     except Maximum Discharge Rate.                                                                                                                         
                                         Free Oil..............  No free oil...........  Once/day prior to      Static sheen; Method   Number of days sheen 
                                                                                          discharge.             at 58 FR 12506.        observed.           
                                         Volume................  Report................  Once/month...........  Estimate.............  Monthly total in bbl/
                                                                                                                                        month.              
    Produced Water.....................  Oil and Grease........  42 mg/l daily maximum   Once/month c.........  Grab/Gravimetric.....  Daily max. and       
                                                                  and 29 mg/l monthly                                                   monthly avg.        
                                                                  average.                                                                                  
                                         Toxicity..............  Acute toxicity (LC50);  Once/month...........  Grab/96-hour LC50      Minimum LC50 for both
                                                                  critical dilution as                           using Mysidopsis       species and full    
                                                                  specified by the                               bahia and sheepshead   laboratory report.  
                                                                  requirements at Part                           minnows (Method in                         
                                                                  I.B.3(a) and Appendix                          EPA/600/4-85/013).                         
                                                                  A of this permit.                                                                         
                                         Flow (bbl/month)......  ......................  Once/month...........  Estimate.............  Monthly rate.        
                                         Within 1000 meters of   No discharge..........                                                                     
                                          an Area of Biological                                                                                             
                                          Concern (ABC).                                                                                                    
    Deck Drainage......................  Free Oil..............  No free oil...........  Once/day when          Visual sheen.........  Number of days sheen 
                                                                                          discharging d.                                observed.           
                                         Volume (bbl/month)....  ......................  Once/month...........  Estimate.............  Monthly total.       
    Produced Sand......................  No Discharge..........                                                                                             
    Well Treatment, Completion, and      Free Oil..............  No free oil...........  Once/day when          Static sheen.........  Number of days sheen 
     Workover Fluids (includes packer    Oil and Grease........  42 mg/l daily maximum    discharging.          Grab/Gravimetric.....   observed.           
     fluids) e.                                                   and 29 mg/l monthly    Once/month...........                         Daily max. and       
                                                                  average.                                                              monthly avg.        
                                         Priority Pollutants...  No priority pollutants  .....................  Monitor added                               
                                                                                                                 materials.                                 
                                         Volume (bbl/month)....  ......................  Once/month...........  Estimate.............  Monthly total.       
    Sanitary Waste (Continuously manned  Solids................  No floating solids....  Once/day, in daylight  Observation..........  Number of days solids
     by 10 or more persons) f.           Residual Chlorine.....  At least (but as close  Once/month...........  Grab/Hach CN-66-DPD..   observed.           
                                         Flow (MGD)............   to) 1 mg/l.            Once/month...........  Estimate.............  Concentration.       
                                                                 ......................                                                                     
    
    [[Page 875]]
    
                                                                                                                                                            
    Sanitary Waste (Continuously manned  Solids................  No floating solids....  Once/day, in daylight  Observation..........  Number of days solids
     by 9 or fewer persons or                                                                                                           observed.           
     intermittently by any) f.                                                                                                                              
    Domestic Waste.....................  Solids................  No floating solids; no  Once/day following     Observation..........  Number of days solids
                                                                  food waste within 12    morning or midday                             observed.           
                                                                  miles of land;          meal at time of                                                   
                                                                  comminuted food waste   maximum expected                                                  
                                                                  smaller than 25-mm      discharge.                                                        
                                                                  beyond 12 miles.                                                                          
    Miscellaneous Discharges--           Free Oil..............  No free oil...........  Once/day when          Visual sheen.........  Number of days sheen 
     Desalination Unit, Blowout                                                           discharging.                                  observed.           
     Preventer, Fluid, Uncontaminated                                                                                                                       
     Ballast/Bilge Water, Mud,                                                                                                                              
     Cuttings, and Cement at the                                                                                                                            
     Seafloor, Uncontaminated Seawater,                                                                                                                     
     Boiler Blowdown, Source Water and                                                                                                                      
     Sand, Diatomaceous Earth Filter                                                                                                                        
     Media.                                                                                                                                                 
    --------------------------------------------------------------------------------------------------------------------------------------------------------
    a Toxicity test to be conducted using suspended particulate phase (SPP) of a 9:1 seawater:mud dilution. The sample shall be taken beneath the shale     
      shaker, or if there are no returns across the shaker, the sample must be taken from a location that is characteristic of the overall mud system to be 
      discharged.                                                                                                                                           
    b Sample shall be taken after the final log run is completed and prior to bulk discharge.                                                               
    c The daily maximum concentration may be based on the average of up to four grab sample results in the 24 hour period.                                  
    d When discharging and facility is manned. Monitoring shall be accomplished during times when observation of a visual sheen on the surface of the       
      receiving water is possible in the vicinity of the discharge.                                                                                         
    e No discharge of priority pollutants except in trace amounts. Information on the specific chemical composition shall be recorded but not reported      
      unless requested by EPA.                                                                                                                              
    f Any facility that properly operates and maintains a marine sanitation device (MSD) that complies with pollution control standards and regulations     
      under Section 312 of the Act shall be deemed to be in compliance with permit limitations for sanitary waste. The MSD shall be tested yearly for proper
      operation and test results maintained at the facility.                                                                                                
    
    Appendix A
    
        Effluent concentrations at the edge of a 100-m mixing zone will 
    be modeled by EPA for each produced water outfall listed in an 
    operator's notice of commencement of production operations. This 
    projected effluent concentration will be used to calculate the 
    permit limitation for produced water toxicity (0.01 x projected 
    effluent concentration). The discharge will be modeled using each 
    facility's measured water column conditions and discharge 
    configurations as input for the CORMIX expert system for 
    hydrodynamic mixing zone analysis.
        The notice of commencement of production operations will be 
    accompanied by a completed CORMIX input parameter table presented as 
    Table A-1. The input parameters required are the following.
    
    Anticipated average discharge rate (bbl/day)
    Water depth (meters)
    Discharge pipe location in the water column (meters from surface or 
    bottom)
    Discharge pipe orientation with respect to the prevailing current 
    (degrees; 0 deg. is coflowing)
    Discharge pipe opening diameter (meters)
    
        These parameters are site-specific parameters that the operator 
    must determine through monitoring or measurement and certify as true 
    to the best of their knowledge. All other input parameters for the 
    CORMIX model are established as the following.
    
    Discharge density: 1070.2 kg/m\3\
    Discharge concentration: 100%
    Legal mixing zone: 100 meters
    Darcy-Wiesbach constant: 0.2
    Current speed: 5 cm/sec
    Discharge pipe orientation: Coflowing with current
    Linear water column density profile;
        Surface density: 1,023.0 kg/m\3\
        Density gradient: 0.163 kg/m\3\/m
    
        The Region will conduct the model using the operator's input 
    parameters and report the toxicity limitation to the operator. If 
    the parameters supplied by the operator change during the life of 
    the permit (e.g., average discharge rate increases or decreases, a 
    change in discharge pipe orientation, etc.), the operator should 
    submit the new input parameters to the Region so that a new toxicity 
    limitation can be calculated.
        Compliance with the toxicity limitation will be demonstrated by 
    conducting 96-hour toxicity tests using mysids (Mysidopsis bahia) 
    and sheepshead minnows (Cyprinodon variegatus) each month. The LC50 
    for each species will be reported on the DMR and a copy of the 
    complete laboratory report shall be submitted.
    
     Table A-1. CORMIX1 Input Parameters for Toxicity Limitation Calculation
    Permit number:             GMG28 ____________                           
    Company:                   ____________                                 
    
    [[Page 876]]
    
                                                                            
    Contact name/Phone         __________                                   
     number:                                                                
                               ........................                     
     ________________________                                               
     _____                                                                  
    Lease block/number:        ______________                               
    Facility name:             ____________                                 
                                                                            
        Parameter Units            Units                                    
    Discharge Rate             ____________ Average bbl/                    
                                day                                         
    Water depth                ____________ meters                          
    Discharge pipe location in the water column                             
                                                                            
        _____________________                                               
         _________                                                          
    (1) meters from ______                                                  
     water surface, or ______                                               
     seafloor                                                               
                                                                            
    Discharge pipe orientation with respect to the seafloor:                
                                                                            
        _____________________  degrees                   (90 deg. is        
         _________                                        directed toward   
                                                          the surface)      
                                                         (-90 deg. is       
                                                          directed toward   
                                                          the seafloor)     
    Discharge pipe opening                                                  
     diameter:                                                              
                                                                            
        _____________________  meters                                       
         _________                                                          
                                                                            
    
    
    BILLING CODE: 6560-50-P
    
    [[Page 877]]
    
    [GRAPHIC] [TIFF OMITTED] TN07JA98.000
    
    
    
    [FR Doc. 98-245 Filed 1-6-98; 8:45 am]
    BILLING CODE 6560-50-C
    
    
    

Document Information

Published:
01/07/1998
Department:
Environmental Protection Agency
Entry Type:
Notice
Action:
Notice of Revised Draft (NPDES) General Permit Reissuance, Notice to States of Mississippi, Alabama and Florida for Consistency Review with approved Coastal Management Programs.
Document Number:
98-245
Dates:
Comments on this proposed action must be received by February 23, 1998.
Pages:
846-877 (32 pages)
Docket Numbers:
FRL-5947-1
PDF File:
98-245.pdf