Water pollution; discharge of pollutants (NPDES): Gulf of Mexico; Eastern portion of Outer Continental Shelf,

[Federal Register: January 7, 1998 (Volume 63, Number 4)]

[Notices]

[Page 846-877]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr07ja98-84]

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.

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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

1. Previous OCS General Permit

2. Discussion of three (3) Alternatives Examined by EIS

3. Conclusions from EIS and more information on Biological Communities

4. Proposed Eastern Gulf of Mexico General Permits

   (1) New Sources

   (2) Existing Sources

   (3) Application Procedures

5. Proposed Individual Permits

6. Basis for Extending General Permit Coverage into the Central Planning Area

7. Description of Designated Areas of Biological Concern in the Central Planning Area

8. 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

1. 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

2. Ocean Discharge Criteria

3. Section 308 of the Clean Water Act V. Summary of New or Changed Permit Limitations and Conditions

1. Alternative Toxicity Requests

2. Cadmium and Mercury in Barite

3. New Sources

4. Free Oil

5. Produced Sand

6. Produced Water

7. Diesel Oil Prohibition

8. Water Quality-Based Effluent Limitations and Conditions

   I. Aquatic Toxicity Limits & Testing Requirements for Produced Water

10. Discharge Prohibition in Vicinity of Areas of Biological Concern

11. Rubbish, Trash, and Other Refuse (MARPOL)

    L. 24-hr Reporting Requirement

13. Reopener Clause

14. Clarifications VI. Specific Permit Conditions

1. Determination of Discharge Conditions

2. Area and Depth-Related Requirements

3. Section 403(c) Requirements VII. Other Legal Requirements

1. National Environmental Protection Act

2. Oil Spill Requirements

3. Ocean Discharge Criteria Evaluation

4. Coastal Zone Management Act

5. Marine Protection, Research, and Sanctuaries Act

6. Executive Order 12291

7. Paperwork Reduction Act

8. 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

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   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.

1. 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.

2. 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.

3. 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.

4. 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.

5. 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).

6. 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

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   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.

7. Description of Designated Areas of Biological Concern in the Central Planning Area

1. 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.

8. 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

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   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

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   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.

2. 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).

3. 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).

1. 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.

2. 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.

3. 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

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   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.

4. 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.

5. 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.

6. 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.

7. 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.

8. 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

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   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

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   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.

10. 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.

11. 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.

13. 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:

    1. Contains different conditions or is otherwise more stringent than any condition in the permit; or

    2. 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).

14. 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

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    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

1. 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.

2. 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.

3. 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 filedor 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

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   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.

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   (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 ‹plus-minus›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.

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   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 ‹SUP›a............ 30,000 ppm daily

   Once/month Once/end Grab/96-hr LC50 using Minimum LC50 of tests minimum.

   of well ‹SUP›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 ‹SUP›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 ‹SUP›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) ‹SUP›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) ‹SUP›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) ‹SUP›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.

   ‹SUP›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.

   ‹SUP›b Sample shall be taken after the final log run is completed and prior to bulk discharge.

   ‹SUP›c The daily maximum concentration may be based on the average of up to four grab sample results in the 24 hour period.

   ‹SUP›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.

   ‹SUP›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.

   ‹SUP›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 ‹SUP›a............ 30,000 ppm daily

   Once/month Once/end Grab/96-hr LC50 using Minimum LC50 of tests minimum.

   of well ‹SUP›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 ‹SUP›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 ‹SUP›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) ‹SUP›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) ‹SUP›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) ‹SUP›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.

   ‹SUP›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.

   ‹SUP›b Sample shall be taken after the final log run is completed and prior to bulk discharge.

   ‹SUP›c The daily maximum concentration may be based on the average of up to four grab sample results in the 24 hour period.

   ‹SUP›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.

   ‹SUP›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.

   ‹SUP›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. 98-245Filed1-6-98; 8:45 am]

   BILLING CODE 6560-50-C