[Federal Register Volume 63, Number 211 (Monday, November 2, 1998)]
[Notices]
[Pages 58722-58738]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-29307]


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ENVIRONMENTAL PROTECTION AGENCY

[FRL-6182-7]


Final NPDES General Permit for New and Existing Sources and New 
Dischargers in the Offshore Subcategory of the Oil and Gas Extraction 
Category for the Western Portion of the Outer Continental Shelf of the 
Gulf of Mexico (GMG290000)

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of Final NPDES General Permit.

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SUMMARY: EPA Region 6 today issues in part the National Pollutant 
Discharge

[[Page 58723]]

Elimination System (NPDES) general permit for the Western Portion of 
the Outer Continental Shelf of the Gulf of Mexico (No. GMG290000) for 
discharges from new sources, existing sources, and new dischargers in 
the Offshore Subcategory of the Oil and Gas Extraction Point Source 
Category (40 CFR part 435, subpart A). The existing permit published in 
the Federal Register at 61 FR 41609 on August 9, 1996 authorized 
discharges from exploration, development, and production facilities 
located in and discharging to Federal waters of the Gulf of Mexico 
seaward of the outer boundary of the territorial seas offshore off 
Louisiana and Texas. The discharge of produced water to that portion of 
the Outer Continental Shelf from Offshore Subcategory facilities 
located in the territorial seas off Louisiana and Texas was also 
authorized by that permit.

FOR FURTHER INFORMATION CONTACT: Ms. Wilma Turner, EPA Region 6, 1445 
Ross Avenue, Dallas, Texas 75202, Telephone: (214) 665 7516, or via 
EMAIL to the following address: [email protected]

SUPPLEMENTAL INFORMATION:

Regulated Entities

    Entities potentially regulated by this action are those which 
operate offshore oil and gas extraction facilities located in the Outer 
Continental Shelf Offshore of Louisiana and Texas.

------------------------------------------------------------------------
                                                Examples of regulated
                 Category                             entities
------------------------------------------------------------------------
Industry..................................  Offshore Oil and Gas
                                             Extraction Platforms.
------------------------------------------------------------------------

    This table lists the types of entities that EPA is now aware could 
potentially be regulated by this action. Other types of entities not 
listed in the table could also be regulated. To determine whether your 
[facility, company, business, organization, etc.] is regulated by this 
action, you should carefully examine the applicability criteria in part 
I, section A.1. of the general permit. If you have questions regarding 
the applicability of this action to a particular entity, consult the 
person listed in the preceding FOR FURTHER INFORMATION CONTACT section.
    Pursuant to section 402 of the Clean Water Act (CWA), 33 U.S.C. 
1342, EPA proposed and solicited comments on NPDES general permit 
GMG290000 at 63 FR 2238 (January 14, 1998). Notice of this proposed 
permit was also published in the New Orleans Times Picayune on January 
24, 1998. The comment period closed on March 16, 1998.
    Region 6 received comments from the Offshore Operators Committee, 
American Petroleum Institute, Willie R. Taylor--United States 
Department of Interior, Shell Offshore, Inc., BP Exploration, Inc., and 
Exxon Company, U.S.A.
    EPA Region 6 has considered all comments received. In response to 
those comments, the final decision to authorize the discharge of 
produced water is being postponed and will not be made at this time; 
however, all other discharges which were proposed are being authorized 
by the permit issued today. Due to the complexity of comments regarding 
produced water discharges, the Region could not adequately respond and 
issue the permit in a timely manner. A final decision on produced water 
discharges will be issued as soon as the Region can adequately respond 
to the related comments.
    One of the comments concerning the produced water toxicity 
requirements raised the same issue with respect to the toxicity 
requirements for seawater and freshwater to which treatment chemicals 
have been added. That issue concerns Version 3.20 of CORMIX, the 
computer model which was used to calculate the proposed permit's 
toxicity limits. The Region is, nevertheless, authorizing in today's 
permit the discharge of freshwater and seawater to which treatment 
chemicals have been added with the limits as stated in the proposed 
permit. The Region has decided to go forward with the limits for 
discharges of freshwater and seawater to which treatment chemicals have 
been added for a number of reasons. First, the Region believes these 
limits are technically defensible and reasonable. The Region also 
recognizes an environmental need to issue standards for the discharge 
of freshwater and seawater to which treatment chemicals have been 
added, because such discharges are not currently authorized. Finally, 
if modifications to the limits are warranted after further review and 
analysis of the CORMIX computer model, the Region expects to make such 
modifications in the near future.
    The Offshore Operators Committee (OOC) has indicated its support of 
the Region's approach, since a number of their members indicated a 
desire to discharge those waste streams as soon as possible. The OOC 
has stated they have no objection to including in today's permit of all 
of the proposed effluent limits for the freshwater and seawater to 
which treatment chemicals have been added, with the understanding that 
(1) when the Agency develops the second phase of the permit; i.e., 
authorizes the discharge of produced water, it will investigate all 
issues raised in OOC's comments regarding the use of the dispersion 
model used to derive the toxicity limits, and (2) if the Agency 
determines the model is inappropriate, it will modify the associated 
limits as a part of issuance of the second phase of the permit.
    In response to other comments received, only minor changes in the 
permit's wording were made in the final permit. A copy of the Response 
to Comments may be obtained from Wilma Turner at the address listed 
above.

Other Legal Requirements

Ocean Discharge Criteria Evaluation

    At 63 FR 2238, EPA Region 6 determined that discharges in 
compliance with the proposed general permit for the Western Gulf of 
Mexico Outer Continental Shelf general permit (GMG290000) would not 
cause unreasonable degradation of the marine environment. No comments 
have been received which disagree with that determination.

Coastal Zone Management Act

    The Region found the proposed general permit consistent with 
approved Coastal Zone Management Plans for Louisiana and Texas and 
submitted those determinations to the appropriate State agencies for 
certification. Such certification was received from the Coastal 
Management Division of the Louisiana Department of Natural Resources. 
However, the Texas General Land Office informed EPA that this action is 
not subject to their consistency review, since the area covered under 
the permit is outside the Texas Coastal Management Program's boundary.

Marine Protection, Research, and Sanctuaries Act

    The Marine Protection, Research and Sanctuaries Act (MPRSA) of 1972 
regulates the dumping of all types of materials into ocean waters and 
establishes a permit program for ocean dumping. In addition the MPRSA 
establishes Marine Sanctuaries Program, implemented by the National 
Oceanographic and Atmospheric Administration (NOAA), which requires 
NOAA to designate ocean waters as marine sanctuaries for the purpose of 
preserving or restoring their conservation, recreational, ecological or 
aesthetic values. Pursuant to the Marine Protection and Sanctuaries 
Act, the National Oceanographic and Atmospheric Administration has 
designated the Flower Garden Banks, an area within the coverage of the 
OCS

[[Page 58724]]

general permit, a marine sanctuary. The OCS general permit prohibits 
discharges in areas of biological concern, including marine 
sanctuaries. No change adopted today affects that prohibition.

Endangered Species Act

    As explained at 63 FR 2238, EPA has found that issuance of the 
General Permit for the Outer Continental for the Western Gulf of Mexico 
will not adversely affect any listed threatened or endangered species 
or designated critical habitat and requested written concurrence on 
that determination from the National Marine Fisheries Service. The 
National Marine Fisheries Service provided such concurrence on the 
proposed NPDES General Permit for the Western Portion of the Outer 
Continental Shelf of the Gulf of Mexico.

State Water Quality Standards and State Certification

    Because state waters are not included in the area covered by this 
NPDES general permit, no state waters are affected by the discharges it 
authorizes. Thus, the state water quality certification provisions of 
CWA section 401 do not apply to this permit.

Executive Order 12866

    The Office of Management and Budget (OMB) has exempted this action 
from the review requirements of Executive Order 12291 pursuant to 
section 8(b) of that order. Guidance on Executive Order 12866 contain 
the same exemptions on OMB review as existed under Executive Order 
12291. In fact, however, EPA prepared a regulatory impact analysis in 
connection with its promulgation of guidelines on which a number of the 
permit's provisions are based and submitted it to OMB for review. See 
58 FR 12494.

Paperwork Reduction Act

    The information collection required by this permit 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).
    Since this permit is very similar in reporting and application 
requirements and in discharges which are required to be monitored as 
the previous Western Gulf of Mexico Outer Continental Shelf (OCS) 
general permit (GMG290000) the paperwork burdens are expected to be 
nearly identical. When it issued the previous OCS general permit, EPA 
estimated it would take an affected facility three hours to prepare the 
request for coverage and 38 hours per year to prepare discharge 
monitoring reports. Although produced water discharges are not 
authorized by the permit at this time, it is estimated that the time 
required to prepare the request for coverage and discharge monitoring 
reports for the reissued permit will be approximately the same.

Regulatory Flexibility Act

    The Regulatory Flexibility Act, 5 U.S.C. 601 et seq,io0 requires 
that EPA prepare a regulatory flexibility analysis for regulations that 
have a significant impact on a substantial number of small entities. As 
indicated below, the permit issued today is not a ``rule'' subject to 
the Regulatory Flexibility Act . EPA prepared a regulatory flexibility 
analysis, however, on the promulgation of the Offshore Subcategory 
guidelines on which many of the permit's effluent limitations are 
based. That analysis shows that issuance of this permit will not have a 
significant impact on a substantial number of small entities.

Unfunded Mandates Reform Act

    Section 201 of the Unfunded Mandates Reform Act (UMRA), Public Law 
104-4, generally requires Federal agencies to assess the effects of 
their ``regulatory actions'' on State, local, and tribal governments 
and the private sector. As stated in the Federal Register document for 
the proposed permit, this permit is not a rule which is subject to the 
requirements of the UMRA. The permit also would not uniquely affect 
small governments because compliance with the proposed permit 
conditions affects small governments in the same manner as any other 
entities seeking coverage under the permit. Additionally, EPA does not 
expect small governments to operate facilities authorized to discharge 
by this permit. No comments were received which challenge EPA's 
interpretation of the Unfunded Mandates Reform Act, as it applies to 
this permit.

National Environmental Policy Act (NEPA)

    As stated in the Federal Register notice for the proposed permit 
(see 63 FR 2238, January 14, 1998) EPA determined that reissuance of 
this NPDES general permit will not result in any new impacts which were 
not subjected to NEPA analysis in either Mineral Management Service's 
EIS or the SEIS produced by EPA Region 6. All discharges authorized by 
this reissued permit were addressed in that NEPA Review. Thus EPA did 
not prepare a supplemental environmental impact statement for this 
action. No comments, on the proposed permit, were received which would 
suggest additional actions are required to meet the requirements of 
NEPA.

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. the ``Act''), operators of lease 
blocks in the Oil and Gas Extraction Point Source Category which are 
located in Federal waters of the Western Portion of the Gulf of Mexico 
(defined as seaward of the outer boundary of the territorial seas off 
Louisiana and Texas) are authorized to discharge to the Western Portion 
of the Federal Waters of the Gulf of Mexico in accordance with effluent 
limitations, monitoring requirements, and other conditions set forth in 
parts I, II, and III hereof.
    Operators of lease blocks located within the general permit area 
must submit written notification to the Regional Administrator that 
they intend to be covered (see part I.A.2). Unless otherwise notified 
in writing by the Regional Administrator after submission of the 
notification, owners or operators requesting coverage are authorized to 
discharge under this 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 
this general permit to discharge pollutants from those facilities. 
Operators who have previously submitted a written notification of 
intent to be covered by a subsequent permit, as required by the 
previous permit, need not submit an additional notification of intent 
to be covered.
    Facilities which adversely affect properties listed or eligible for 
listing in the National Register of Historic Places are not authorized 
to discharge under this permit.
    This permit shall become effective at Midnight Central Daylight 
Savings Time on November 2, 1998.
    This permit and the authorization to discharge shall expire at 
midnight,

[[Page 58725]]

Central Standard Time, November 3, 2003.
William B. Hathaway,
Director, Water Quality Protection Division, Region 6.

Part I. Requirements for NPDES Permits

Section A. Permit Applicability and Coverage Conditions

1. Operations Covered
    This permit establishes effluent limitations, prohibitions, 
reporting requirements, and other conditions on discharges from oil and 
gas facilities engaged in production, field exploration, developmental 
drilling, well completion, well treatment operations, and well workover 
and abandonment operations.
    The permit coverage area consists of lease blocks located in and 
discharging to Federal waters in the Gulf of Mexico seaward of the 
outer boundary of the territorial seas offshore of Louisiana and Texas 
and shall include lease blocks west of the western boundary of the 
outer continental shelf lease areas defined as: Mobile, Viosca Knoll 
(north part), Destin Dome, Desoto Canyon, Lloyd, and Henderson. In 
Texas, where the state has mineral rights to 3 leagues, some operators 
with state lease tracts are required to request coverage under this 
Federal NPDES general permit. This permit does not authorize discharges 
from facilities located in or discharging to the territorial seas of 
Louisiana or Texas or from facilities defined as ``coastal,'' 
``onshore,'' or ``stripper'' (see 40 CFR part 435, subparts C, D, and 
E).
2. Notification Requirements
    Written notification of intent to be covered including the legal 
name and address of the operator, the lease block number assigned by 
the Department of Interior or the state or, if none, the name commonly 
assigned to the lease area shall be submitted at least fourteen days 
prior to the commencement of discharge. If the lease block was 
previously covered by this or another permit, the operator shall also 
include the previous permit number in the notification. The notice of 
intent must also identify any facility which is a New Source and state 
the date on which the facility's protection from more stringent new 
source performance standards or technology based limitations ends. That 
date is the soonest of: ten years from the date that construction is 
completed, ten years from the date the source begins to discharge 
process or non-construction related waste water, or the end of the 
period of depreciation or amortization of the facility for the purposes 
of section 167 or 169 (or both) of the Internal Revenue code of 1954.
    Additionally, if an application for an individual permit for the 
activity was previously submitted to EPA Region 6, the notice of intent 
shall include the application/permit number of that application or the 
permit number of any individual NPDES permit issued by EPA Region 6 for 
this activity.
    Permittees located in lease blocks that (a) are neither in nor 
adjacent to MMS-defined ``no activity'' areas, or (b) do not require 
live-bottom surveys are required only to submit a notice of intent to 
be covered by this general permit. Permittees who are located in lease 
blocks that are either in or adjacent to ``no activity'' areas or 
require live bottom surveys are required to submit both a notice of 
intent to be covered that specifies they are located in such a lease 
block, and in addition are required to submit a notice of commencement 
of operations.
    Permittees located in lease blocks either in or immediately 
adjacent to MMS-defined ``no activity'' areas, shall be responsible for 
determining whether a controlled discharge rate is required. The 
maximum discharge rate for drilling fluids is determined by the 
distance from the facility to the ``no activity'' area boundary and the 
discharge rate equation provided in part I.B.1.b. of this permit. The 
permittee shall report the distance from the permitted facility to the 
``no activity'' area boundary and the calculated maximum discharge rate 
to EPA with its notice of commencement of operations.
    For permittees located in lease blocks that require live-bottom 
surveys, the final determination of the presence or absence of live-
bottom communities, the distance of the facility from identified live-
bottom areas, and the calculated maximum discharge rate shall be 
reported with the notice of commencement of operations.
    All notifications of intent to be covered and any subsequent 
reports under this permit shall be sent to the following address: Water 
Enforcement Branch (6EN-WC), Region 6, U.S. Environmental Protection 
Agency, P.O. Box 50625, Dallas, TX 75250. Operators who have previously 
submitted a written notification of intent to be covered by a 
subsequent permit, as required by the previous permit, need not submit 
an additional notification of intent to be covered.
3. Termination of Operations
    Lease block operators shall notify the Regional Administrator 
within 60 days after the permanent termination of discharges from their 
facilities within the lease block.

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 Table 2 of appendix A and as below.

    Special Note: The permit prohibitions and limitations that apply 
to drilling fluids, also apply to fluids that adhere to drill 
cuttings. Any permit condition that may apply to the drilling fluid 
discharges, therefore, also applies to cuttings discharges.

    [Exception] The discharge rate limit for drilling fluids does not 
apply to drill cuttings.
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 
which contain waste engine oil, cooling oil, gear oil or any lubricants 
which have been previously used for purposes other than borehole 
lubrication, is prohibited.
    Diesel Oil. Drilling fluids to which any diesel oil has been added 
as a lubricant may not be discharged.
b. Limitations
    Mineral Oil. Mineral oil may be used only as a carrier fluid 
(transporter fluid), lubricity additive, or pill.
    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 all stock barite used once, 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 on 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 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

[[Page 58726]]

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 96-hour LC50 of at least 30,000 
ppm in a 9:1 seawater to drilling fluid suspended particulate phase 
(SPP) volumetric ratio using Mysidopsis bahia. Monitoring shall be 
performed at least once per month for both a daily minimum and the 
monthly average. In addition, an end-of-well sample is required for a 
daily minimum. The type of sample required is a grab sample, taken from 
beneath the shale shaker, or if there are no returns accross the shale 
shaker, the sample must be taken from a location that is characteristic 
of the overall mud system to be discharged. Permittees shall report 
pass or fail on the DMR using either the full toxicity test or the 
partial toxicity test as specified at 58 FR 12512; however, if the 
partial toxicity test shows a failure, all testing of future samples 
from that well shall be conducted using the full toxicity test method 
to determine the 96-hour LC50.
    Free Oil. No free oil shall be discharged. Monitoring shall be 
performed using the static sheen method once per week when discharging. 
The number of days a sheen is observed must be recorded.
    Discharge Rate. All facilities are subject to a maximum discharge 
rate of 1,000 barrels per hour.
    For those facilities subject to the discharge rate limitation 
requirement because of their proximity to areas of biological concern, 
the discharge rate of drilling fluids shall be determined by the 
following equation:

R = 10 [3 Log (d/15) + Tt]
Where:
R = discharge rate (bbl/hr)
d = distance (meters) from the boundary of a controlled discharge rate 
area
Tt
    = toxicity-based discharge rate term
    = [log (LC50 x 8 x 10-6)] / 0.3657

    Drilling fluids discharges (based on a mud toxicity of 30,000 ppm) 
equal to or less than 544 meters from areas of biological concern shall 
comply with the discharge rate obtained from the equation above. 
Drilling fluids discharges which are shunted to the bottom as required 
by MMS lease stipulation are not subject to this discharge rate control 
requirement.
    All discharged drilling fluids, including those fluids adhering to 
cuttings must meet the limitations of this section except that 
discharge rate limitations do not apply before installation of the 
marine riser.
C. Monitoring Requirements
    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.
2. Drill Cuttings
    The discharge of drill cuttings shall be limited and monitored by 
the permittee as specified in appendix A, Table 2 and as below.
a. Prohibitions
    Cuttings from Oil Based Drilling Fluids. The discharge of cuttings 
that are generated while using an oil-based or invert emulsion mud is 
prohibited.
    Cuttings from Oil Contaminated Drilling Fluids. The discharge of 
cuttings that are generated using drilling fluids which 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.
    Cadmium and Mercury in Barite. Drill cuttings generated using 
drilling fluids to which barite has been added shall not be discharged 
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).
    Toxicity. Drill cuttings generated using drilling fluids with a 
daily minimum or a monthly average minimum 96-hour LC50 of less than 
30,000 ppm in a 9:1 seawater to drilling fluid suspended particulate 
phase (SPP) volumetric ratio using Mysidopsis bahia shall not be 
discharged.
b. Limitations
    Free Oil. No free oil shall be discharged. Monitoring shall be 
performed using the static sheen test method once per week when 
discharging. The number of days a sheen is observed must be recorded.
3. Deck Drainage
a. Limitations
    Free Oil. No free oil shall be discharged, as determined by the 
visual sheen method on the surface of the receiving water. Monitoring 
shall be performed once per day when discharging, during conditions 
when an observation of a visual sheen on the surface of the receiving 
water is possible in the vicinity of the discharge, and the facility is 
manned. The number of days a sheen is observed must be recorded.
4. Produced Sand
    There shall be no discharge of produced sand.
5. Well Treatment Fluids, Completion Fluids, and Workover Fluids
a. Limitations
    Free Oil. No free oil shall be discharged. Monitoring shall be 
performed using the static sheen test method once per day when 
discharging and the facility is manned. The number of days a sheen is 
observed must be recorded.
    Oil and Grease. Well treatment, completion, and workover fluids 
must meet both a daily maximum of 42 mg/l and a monthly average of 29 
mg/l limitation for oil and grease. The sample type may be either grab, 
or a 24-hour composite consisting of the arithmetic average of the 
results of 4 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. The analytical method is that specified at 40 CFR part 
136 or the alternate method described in part I.D.5 of this permit.
    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
    This discharge shall be considered produced water for monitoring 
purposes when commingled with produced water.
6. Sanitary Waste (Facilities Continuously Manned by 10 or More 
Persons)
a. Prohibitions
    Solids. No floating solids may be discharged to the receiving 
waters. An observation must be made once per day for floating solids. 
Observation must be made during daylight in the vicinity of sanitary 
waste outfalls following either

[[Page 58727]]

the morning or midday meal and at a time during maximum estimated 
discharge. The number of days solids are observed must be recorded.
b. Limitations
    Residual Chlorine. Total residual chlorine is a surrogate parameter 
for fecal coliform. Discharge of residual chlorine must meet a minimum 
of 1 mg/l and shall be maintained as close to this concentration as 
possible. A grab sample must be taken once per month and the 
concentration recorded (approved method, Hach CN-66-DPD).
    [Exception] Any facility which 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 
in compliance with permit limitations for sanitary waste. The MSD shall 
be tested yearly for proper operation and the test results maintained 
at the facility.
7. Sanitary Waste (Facilities Continuously Manned by 9 or Fewer Persons 
or Intermittently by Any Number)
Prohibitions
    Solids. No floating solids may be discharged to the receiving 
waters. An observation must be made once per day for floating solids. 
Observation must be made 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 must be recorded.
    [Exception] Any facility which 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 the test results 
maintained at the facility.
8. Domestic Waste
a. Prohibitions
    Solids. No floating solids or foam shall be discharged.
b. Monitoring Requirements
    An observation shall be made once per day during daylight in the 
vicinity of domestic waste outfalls following the morning or midday 
meal and at a time during maximum estimated discharge. The number of 
days solids are observed must be recorded.
9. Miscellaneous Discharges
Desalination Unit Discharge
Diatomaceous Earth Filter Media
Blowout Preventer Fluid
Uncontaminated Ballast Water
Uncontaminated Bilge Water
Mud, Cuttings, and Cement at the Seafloor
Uncontaminated Freshwater
Uncontaminated Seawater
Boiler Blowdown
Source Water and Sand
Excess Cement Slurry
Limitations
    Free Oil. No free oil shall be discharged. Discharge is limited to 
those times that a visual sheen observation is possible unless the 
operator uses the static sheen method. Monitoring shall be performed 
using the visual sheen method on the surface of the receiving water 
once per week when discharging, or by use of the static sheen method at 
the operator's option. The number of days a sheen is observed must be 
recorded.
    [Exceptions] Uncontaminated seawater, uncontaminated freshwater, 
source water and source sand, uncontaminated bilge water, and 
uncontaminated ballast water may be discharged from platforms that are 
on automatic purge systems without monitoring for free oil when the 
facilities are not manned. Additionally, discharges at the seafloor of: 
muds and cuttings prior to installation of the marine riser, cement, 
and blowout preventer fluid may be discharged without monitoring with 
the static sheen test when conditions make observation of a visual 
sheen on the surface of the receiving water impossible.
10. Miscellaneous Discharges of Seawater and Freshwater Which Have Been 
Chemically Treated
Excess seawater which permits the continuous operation of fire control 
and utility lift pumps
Excess seawater from pressure maintenance and secondary recovery 
projects
Water released during training of personnel in fire protection
Seawater used to pressure test new piping and new pipelines
Ballast water
Once Through Non-contact cooling water
Desalinization unit discharge
a. Limitations
    Treatment Chemicals. The concentration of treatment chemicals in 
discharged seawater or freshwater shall not exceed the most stringent 
of the following three constraints:
    (1) The maximum concentrations and any other conditions specified 
in the EPA product registration labeling if the chemical is an EPA 
registered product.
    (2) The maximum manufacturer's recommended concentration.
    (3) 500 mg/l.
    Free Oil. No free oil shall be discharged. Discharge is limited to 
those times that a visible sheen observation is possible unless the 
operator uses the static sheen method. Monitoring shall be performed 
using the visual sheen method on the surface of the receiving water 
once per week when discharging, or by use of the static sheen method at 
the operator's option. The number of days a sheen is observed must be 
recorded.
    Toxicity. The 48-hour minimum and monthly average minimum No 
Observable Effect Concentration (NOEC), or if specified the 7-day 
average minimum and monthly average minimum NOEC, must be equal to or 
greater than the critical dilution concentration specified in this 
permit in Table 3-A for seawater discharges and 3-B for freshwater 
discharges. Critical dilution shall be determined using Table 3 of this 
permit and is based on the discharge rate, discharge pipe diameter, and 
water depth between the discharge pipe and the bottom. The monthly 
average minimum NOEC value is defined as the arithmetic average of all 
48-hour average NOEC (or 7-day average minimum NOEC) values determined 
during the month.
b. Monitoring Requirements
    Flow. Once per month, an estimate of the flow (MGD) must be 
recorded.
    Toxicity. The required frequency of testing for continuous 
discharges shall be determined as follows:

------------------------------------------------------------------------
            Discharge rate                 Toxicity testing frequency
------------------------------------------------------------------------
0--499 bbl/day.......................  Once per year.
500--4,599 bbl/day...................  Once per quarter.
4,600 bbl/day and above..............  Once per month.
------------------------------------------------------------------------

    Intermittent or batch discharges shall be monitored once per 
discharge but are required to be monitored no more frequently than the 
corresponding frequencies shown above for continuous discharges.
    Samples shall be collected after addition of any added substances, 
including seawater that is added prior to discharge, and before the 
flow is split for multiple discharge ports. Samples also shall be 
representative of the discharge. Methods to increase dilution 
previously described for produced water in part I.B.4.a also apply to 
seawater and freshwater discharges which have been chemically treated.

[[Page 58728]]

    If the permittee has been compliant with this toxicity limit for 
one full year (12 consecutive months) for a continuous discharge of 
chemically treated seawater or freshwater, the required testing 
frequency shall be reduced to once per year for that discharge.

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 in other than trace amounts.
    [Exception] For new sources, this limitation only applies to 
miscellaneous discharges and domestic waste discharges.
2. Halogenated Phenol Compounds
    There shall be no discharge of halogenated phenol compounds as a 
part of any waste stream 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 the Minerals Management Service. 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, thereby increasing toxicity and 
making the detection of a discharge of oil more difficult.
4. Garbage
    The discharge of garbage (see part II.G.32) is prohibited .
    [Exception] Comminuted food waste (able to pass through a screen 
with a mesh no larger than 25 mm, approx. 1 inch) may be discharged 
when 12 nautical miles or more from land.
5. Area of Biological Concern
    There shall be no discharge in Areas of Biological Concern, 
including marine sanctuaries. The Flower Garden Banks has been 
determined to be a Marine Sanctuary and is within the geographical area 
covered under this permit.

Section D. Other Conditions

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 test method for permit compliance is identified as: 
Drilling Fluids Toxicity Test at 40 CFR part 435, subpart A, appendix 
2.
3. Chemically Treated Seawater and Freshwater Toxicity Testing 
Requirements (48-Hour Acute NOEC Marine Limits)
    The approved test methods for permit compliance are identified in 
40 CFR part 136.
    a. The permittee shall utilize the Mysidopsis bahia (Mysid shrimp) 
acute static renewal 48-hour definitive toxicity test using EPA/600/4-
90/027F.
    b. Menidia beryllina (Inland Silverside minnow) acute static 
renewal 48-hour definitive toxicity test using EPA/600/4-90/027F.
    c. The NOEC (No observable Effect Concentration) is defined as the 
greatest effluent dilution which does not result in lethality that is 
statistically different from the control (0% effluent) at the 95% 
confidence level.
    d. If the effluent fails the survival endpoint at the critical 
dilution, the permittee shall be considered in violation of this permit 
limit. Also, when the testing frequency stated above is less than 
monthly and the effluent fails the survival endpoint at the critical 
dilution, the monitoring frequency for the affected species will 
increase to monthly until such time as compliance with the Lethal No 
Observed Effect Concentration (NOEC) effluent limitation is 
demonstrated for a period of three consecutive months, at which time 
the permittee may return to the testing frequency stated in part 
I.B.11.b of this permit. During the period the permittee is out of 
compliance, test results shall be reported on the DMR for that 
reporting period.
    e. This permit may be reopened to require chemical specific 
effluent limits, additional testing, and/or other appropriate actions 
to address toxicity.
    f. Test Acceptance. The permittee shall repeat a test, including 
the control and all effluent dilutions, if the procedures and quality 
assurance requirements defined in the test methods or in this permit 
are not satisfied, including the following additional criteria:
    (1) Each toxicity test control (0% effluent) must have a survival 
equal to or greater than 90%.
    (2) The percent coefficient of variation between replicates shall 
be 40% or less in the control (0% effluent) for the Mysid shrimp 
survival test and the Inland Silverside minnow survival test.
    (3) The percent coefficient of variation between replicates shall 
be 40% or less in the critical dilution, unless significant lethal 
effects are exhibited for the Mysid shrimp survival test and the Inland 
Silverside minnow survival test.
    Test failure may not be construed or reported as invalid due to a 
coefficient of variation value of greater than 40%. A repeat test shall 
be conducted within the required reporting period of any test 
determined to be invalid.
    g. Statistical Interpretation. For the Mysid shrimp survival test 
and the Inland Silverside minnow survival test, the statistical 
analyses used to determine if there is a statistically significant 
difference between the control and the critical dilution shall be in 
accordance with the methods for determining the No Observed Effect 
Concentration (NOEC) as described in EPA/600/4-90/027F or the most 
recent update thereof.
    If the conditions of Test Acceptability are met in Item 4.f above 
and the percent survival of the test organism is equal to or greater 
than 80% in the critical dilution concentration and all lower dilution 
concentrations, the test shall be considered to be a passing test, and 
the permittee shall report an NOEC of not less than the critical 
dilution for the DMR reporting requirements found in Item i below.
    h. The permittee shall prepare a full report of the results of all 
tests conducted pursuant to this section in accordance with the Report 
Preparation section of ``Methods for Measuring the Acute Toxicity of 
Effluents and Receiving Waters to Freshwater and Marine Organisms,'' 
EPA/600/4-90/027F, or the latest update thereof, for every valid or 
invalid toxicity test initiated whether carried to completion or not. 
The permittee shall retain each full report pursuant to the provisions 
of part II.C.3 of this permit. The permittee shall submit full reports 
only upon the specific request of the Agency.
    i. In accordance with part II.D.4 of this permit, the permittee 
shall report on the DMR for the reporting period whether the lowest 
Whole Effluent Lethality values determined for either species passed 
the 30-Day Average Minimum and 48-Hour Minimum NOEC. In addition, the 
permittee shall report on the DMR the lowest NOEC survival value of the 
two species.
4. Oil and Grease Alternative Test Procedure: Interim Limited Use 
Approval
    Proposed Method 1664 (61 FR 1730, January 23, 1996) may be used as 
an alternative test procedure for NPDES permit compliance monitoring 
purposes. This approval shall expire at

[[Page 58729]]

the time of the publication in the Federal Register of the final rule 
governing the use of Method 1664. This approval includes all of the 
analytical options within Method 1664 provided the equivalency 
demonstration is performed and all performance specifications are met.
5. 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. The operator must conduct a visual sheen test only at 
times when a sheen could be observed. This restriction eliminates 
observations when atmospheric or surface conditions prohibit the 
observer from detecting a sheen (e.g., overcast skies, rough seas, 
etc.).
    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 
a least 15 minutes previously, observations may be made any time 
thereafter. For discharges of less than 15 minutes duration, 
observations must be made during both discharge and at 5 minutes after 
discharge has ceased.
6. Static Sheen Test
    The approved test method for permit compliance is identified as: 
Static Sheen Test at 40 CFR part 435, subpart A, appendix 1.

Part II. Standard Conditions for NPDES Permits

Section A. General Conditions

1. Introduction
    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, (herein-after known as the ``Act'') as well as ALL applicable 
regulations.
2. 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.
3. Toxic Pollutants
    a. 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.
    b. 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.
4. Permit Flexibility
    This permit may be modified, revoked and reissued, or terminated 
for cause in accordance with 40 CFR 122.62-64. 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. Property Rights
    This permit does not convey any property rights of any sort, or any 
exclusive privilege.
6. Duty to Provide Information
    The permittee shall furnish to the Director, within a reasonable 
time, any information which the Director 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 Director, upon request, copies 
of records required to be kept by this permit.
7. Criminal and Civil Liability
    Except as provided in permit conditions on ``Bypassing'' and 
``Upsets,'' nothing in this permit shall be construed to relieve the 
permittee from civil or criminal penalties for noncompliance. Any false 
or materially misleading representation or concealment of information 
required to be reported by the provisions of the permit, the Act, or 
applicable 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. 1001.
8. 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 Act.
9. 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 Act.
10. Severability
    The provisions of this permit are severable, and 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.

Section B. Proper Operation and Maintenance

1. 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. The permittee is responsible for maintaining adequate 
safeguards to prevent the discharge of untreated or inadequately 
treated wastes during electrical power failure either by means of 
alternate power sources, standby generators or retention of 
inadequately treated effluent.
2. 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.
3. Proper Operation and Maintenance
    a. The permittee shall at all times properly operate and maintain 
all facilities and systems of treatment and control (and related 
appurtenances) which are installed or used by permittee as efficiently 
as possible and in a manner which will minimize upsets and discharges 
of excessive pollutants and will achieve compliance with the conditions 
of 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

[[Page 58730]]

installed by a permittee only when the operation is necessary to 
achieve compliance with the conditions of this permit.
    b. The permittee shall provide an adequate operating staff which is 
duly qualified to carry out operation, maintenance and testing 
functions required to insure compliance with the conditions of this 
permit.
4. Bypass of Treatment Facilities
    a. Bypass not exceeding limitations. The permittee may allow any 
bypass to occur which 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 parts II.B.4.b and 4.c.
    b. 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, within 24 hours, 
submit notice of an unanticipated bypass as required in part II.D.7.
    c. Prohibition of Bypass.
    (1) Bypass is prohibited, and the Director 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 which occurred during normal periods of equipment 
downtime or preventive maintenance; and,
    (c) The permittee submitted notices as required by part II.B.4.b.
    (2) The Director may allow an anticipated bypass after considering 
its adverse effects, if the Director determines that it will meet the 
three conditions listed at part II.B.4.c(1).
5. Upset Conditions
    a. 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 part II.B.5.b. 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.
    b. 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 part 
II.D.7; and,
    (4) The permittee complied with any remedial measures required by 
part II.B.2.
    c. Burden of proof. In any enforcement proceeding, the permittee 
seeking to establish the occurrence of an upset has the burden of 
proof.
6. Removed Substances
    Solids, sewage sludges, filter backwash, or other pollutants 
removed in the course of treatment or wastewater control 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. Inspection and Entry
    The permittee shall allow the Director, 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.
2. Representative Sampling
    Samples and measurements taken for the purpose of monitoring shall 
be representative of the monitored activity.
3. 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, 
copies of all reports required by this permit, and records of all data 
used to complete the application for this permit, for a period of at 
least 3 years from the date of the sample, measurement, report, or 
application. This period may be extended by request of the Director 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. The operator is responsible for 
maintaining records at exploratory facilities while they are 
discharging under the operators control and at a specific shore-based 
site for the remainder of the 3-year retention period.
4. 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) and time(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.
5. Monitoring Procedures
    a. Monitoring must be conducted according to test procedures 
approved under 40 CFR part 136, unless other test procedures have been 
specified in this permit or approved by the Regional Administrator.
    b. The permittee shall calibrate and perform maintenance procedures 
on all monitoring and analytical instruments at intervals frequent 
enough to insure accuracy of measurements and shall maintain 
appropriate records of such activities.
    c. An adequate analytical quality control program, including the 
analyses of sufficient standards, spikes, and duplicate samples to 
insure the accuracy of all required analytical results shall be 
maintained by the permittee or designated commercial laboratory.
6. Flow Measurements
    Appropriate flow measurement devices and methods consistent with 
accepted scientific practices shall be selected and used to ensure the

[[Page 58731]]

accuracy and reliability of measurements of the volume of monitored 
discharges. The devices shall be installed, calibrated, and maintained 
to insure that the accuracy of the measurements is consistent with the 
accepted capability of that type of device. Devices selected shall be 
capable of measuring flows with a maximum deviation of less than 10% 
from true discharge rates throughout the range of expected discharge 
volumes.

Section D. Reporting Requirements

1. Planned Changes
    The permittee shall give notice to the Director as soon as possible 
of any planned physical alterations or additions to the permitted 
facility. Notice is required only when:
    (1) The alteration or addition to a permitted facility may meet one 
of the criteria for determining whether a facility is a new source in 
40 CFR part 122.29(b); or,
    (2) 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 
listed at part II.D.10.a.
2. Anticipated Noncompliance
    The permittee shall give advance notice to the Director 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 except after notice 
to the Regional Administrator. The Regional Administrator may require 
modification or revocation and reissuance of the permit to change the 
name of the permittee and to incorporate such requirements as may be 
necessary under the Act.
4. Discharge Monitoring Reports and Other Reports
    The operator of each lease block shall be responsible for 
submitting monitoring results for all facilities within each lease 
block. The monitoring results for the facilities (platform, drilling 
ship, or semisubmersible) within the particular lease block shall be 
summarized on the annual Discharge Monitoring Report for that lease 
block.
    Monitoring results obtained during the previous 12 months shall be 
summarized and reported on a Discharge Monitoring Report (DMR) form 
(EPA No. 3320-1).
    If any category of waste (discharge) is not applicable for all 
facilities within the lease block, due to the type of operations (e.g., 
drilling, production) no reporting is required; however, ``no 
discharge'' must be recorded for those categories on the DMR. Operators 
may list a summary of all lease blocks where there is no activity in 
lieu of DMRs for those lease blocks. The summary must state each lease 
block name and outfall number and must include the monitoring period. 
All pages of the DMR, or summary of no activity lease blocks, must be 
signed and certified as required by part II.D.11 of this permit and 
returned when due.
    Additionally, the lease block number assigned by the Department of 
the Interior shall be listed on all Discharge Monitoring Reports.
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 Discharge Monitoring Report (DMR). Such increased 
monitoring frequency shall also 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.
7. Twenty-Four Hour Reporting
    a. The permittee shall report any noncompliance which may endanger 
health or the environment. Any information shall be provided orally 
within 24 hours from the time the permittee becomes aware of the 
circumstances. Alternatively to oral reporting, the permittee may 
report by EMAIL at the following address: [email protected]. 
A written submission shall be provided within 5 days of the time the 
permittee becomes aware of the circumstances. The report shall contain 
the following information:
    (1) A description of the noncompliance and its cause;
    (2) 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,
    (3) Steps being taken to reduce, eliminate, and prevent recurrence 
of the noncomplying discharge.
    b. The following shall be included as information which must be 
reported within 24 hours:
    (1) Any unanticipated bypass which exceeds any effluent limitation 
in the permit;
    (2) Any upset which exceeds any effluent limitation in the permit; 
and,
    (3) Violation 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.
    c. The Director 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 parts II.D.4 and D.7 at the time monitoring reports are 
submitted. The reports shall contain the information listed at part 
II.D.7.
9. Other Information
    Where the permittee becomes aware that he failed to submit any 
relevant facts in a permit application, or submitted incorrect 
information in a permit application or in any report to the Director, 
he shall promptly submit such facts or information.
10. Signatory Requirements
    All applications, reports, or information submitted to the Director 
shall be signed and certified.
    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:
    (a) A president, secretary, treasurer, or vice-president of the 
corporation in charge of a principal business function, or any other 
person who performs similar policy or decision making functions for the 
corporation; or,
    (b) 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.
    (3) For a municipality, State, Federal, or other public agency--by 
either a principal executive officer or ranking elected official. For 
purposes of this election, a principal executive officer of a Federal 
agency includes:

[[Page 58732]]

    (a) The chief executive officer of the agency, or
    (b) A senior executive officer having responsibility for the 
overall operations of a principal geographic unit of the agency.
     b. All reports required by the permit and other information 
requested by the Director 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 Director.
    c. 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.''
11. Availability of Reports
    Except for applications, effluent data, permits, and other data 
specified in 40 CFR 122.7, any information submitted pursuant to this 
permit may be claimed as confidential by the submitter. If no claim is 
made at the time of submission, information may be made available to 
the public without further notice.

Section E. Penalties for Violations of Permit Conditions

1. Criminal
a. Negligent Violations
    The Act provides that any person who negligently violates permit 
conditions implementing sections 301, 302, 306, 307, 308, 318, or 405 
of the Act is subject to a fine of not less $2,500 nor more then 
$25,000 per day of violation, or by imprisonment for not more than 1 
year, or both.
b. Knowing Violations
    The Act provides that any person who knowingly violates permit 
conditions implementing sections 301, 302, 306, 307, 308, 318 or 405 of 
the Act is subject to a fine 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.
c. Knowing Endangerment
    The Act provides that any person who knowingly violates permit 
conditions implementing sections 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, or by imprisonment for not more 
than 15 years, or both.
 d. False Statements
    The Act provides that any person who knowingly makes any false 
material statement, representation, or certification in any 
application, record report, plan, or other document filed or required 
to be maintained under the Act or who knowingly falsifies, tampers 
with, or renders inaccurate, any monitoring device or method required 
to be maintained under the Act, shall upon conviction, be punished by a 
fine of not more than $10,000, or by imprisonment for not more than 2 
years, or by both. If a conviction of a person is for a violation 
committed after a first conviction of 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.4 of the Clean Water Act).
2. Civil Penalties
    The Act provides that any person who violates a permit condition 
implementing sections 301, 302, 306, 307, 308, 318, or 405 of the Act 
is subject to a civil penalty not to exceed $27,500 per day for each 
violation.
3. Administrative Penalties
    The Act provides that any person who violates a permit conditions 
implementing sections 301, 302, 306, 307, 308, 318, or 405 of the Act 
is subject to an administrative penalty, as follows:
a. Class I Penalty
    Not to exceed $11,000 per violation nor shall the maximum amount 
exceed $27,500.
b. Class II Penalty
    Not to exceed $11,000 per day for each day during which the 
violation continues nor shall the maximum amount exceed $137,500.

Section F. Additional General Permit Conditions

1. When the Regional Administrator May Require Application for an 
Individual NPDES Permit
    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 limitations 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. The point source(s) covered by this permit no longer:
    (1) Involve the same or substantially similar types of operations;
    (2) Discharge the same types of wastes;
    (3) Require the same effluent limitations or operating conditions;
    (4) Require the same or similar monitoring; and
    (5) In the opinion of the Regional Administrator, are more 
appropriately controlled under an individual permit than under a 
general permit.
    g. The bioaccumulation monitoring results show concentrations of 
the listed pollutants in excess of levels safe for human consumption.
    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.
2. When an Individual NPDES Permit May be Requested
    a. Any operator authorized by this permit may request to be 
excluded from the coverage of this general permit by applying for an 
individual permit.
    b. When an individual NPDES permit is issued to an operator 
otherwise

[[Page 58733]]

subject to this general permit, the applicability of this permit to the 
owner or operator is automatically terminated on the effective date of 
this individual permit.
    c. 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.
3. Permit Reopener Clause
    If applicable new or revised effluent limitations guidelines or New 
Source Performance Standards covering the Offshore Subcategory of the 
Oil and Gas Extraction Point Source Category (40 CFR part 435) are 
promulgated in accordance with sections 301(b), 304(b)(2), and 
307(a)(2), and the new or revised effluent limitations guidelines or 
New Source Performance Standards are more stringent than any effluent 
limitations in this permit or control a pollutant not limited in this 
permit, the permit may, at the Director's discretion, be modified to 
conform to the new or revised effluent limitations guidelines.
    Notwithstanding the above, if an offshore oil and gas extraction 
point source discharge facility is subject to the ten year protection 
period for new source performance standards under the Clean Water Act 
section 306(d), this reopener clause may not be used to modify the 
permit to conform to more stringent new source performance standards or 
technology based standards developed under section 301(b)(2) during the 
ten year period specified in 40 CFR part 122.29(d).
    The Director may modify this permit upon meeting the conditions set 
forth in this reopener clause.

Section G. Definitions

    All definitions contained in section 502 of the Act shall apply to 
this permit and are incorporated herein by references. Unless otherwise 
specified in this permit, additional definitions of words or phrases 
used in this permit are as follows:
    1. ``Act'' means the Clean Water Act (33 U.S.C. 1251 et. seq.), as 
amended.
    2. ``Administrator'' means the Administrator of the U.S. 
Environmental Protection Agency.
    3. ``Annual Average'' means the average of all discharges sampled 
and/or measured during a calendar year in which daily discharges are 
sampled and/or measured, divided by the number of discharges sampled 
and/or measured during such year.
    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 or performance, toxic effluent 
standards and prohibitions, and pretreatment standards.
    5. ``Applicable water quality standards'' means all water quality 
standards to which a discharge is subject under the Act.
    6.``Areas of Biological Concern'' means a portion of the OCS 
identified by EPA, in consultation with the Department of Interior as 
containing potentially productive or unique biological communities or 
as being potentially sensitive to discharges associated with oil and 
gas activities.
    7. ``Blow-Out Preventer Control Fluid'' means fluid used to actuate 
the hydraulic equipment on the blow-out preventer or subsea production 
wellhead assembly.
    8. ``Boiler Blowdown'' means discharges from boilers necessary to 
minimize solids build-up in the boilers, including vents from boilers 
and other heating systems.
    9. ``Bulk Discharge'' 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.
    10. ``Bypass'' means the intentional diversion of waste streams 
from any portion of a treatment facility.
    11. ``Completion Fluids'' means salt solutions, weighted brines, 
polymers and various additives used to prevent damage to the well bore 
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.
    12. ``Controlled Discharge Rates Areas'' means zones adjacent to 
areas of biological concern.
    13. ``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 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 arithmetic 
average (weighted by flow value) of all samples collected during that 
sampling day.
    14. ``Daily Average'' (also known as monthly average) discharge 
limitations means the highest allowable average of 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. When the permit establishes 
daily average concentration effluent limitations or conditions, the 
daily average concentration means the arithmetic average (weighted by 
flow) of all daily discharge(s) of concentration determined during the 
calendar month where C = daily concentration, F = daily flow, and n = 
number of daily samples; daily average discharge =
[GRAPHIC] [TIFF OMITTED] TN02NO98.276

    15. ``Daily Maximum'' discharge limitations means the highest 
allowable ``daily discharge'' during the calendar month.
    16. ``Desalinization Unit Discharge'' means wastewater associated 
with the process of creating freshwater from seawater.
    17. ``Deck Drainage'' means any waste resulting from deck washings, 
spillage, rainwater, and runoff from gutters and drains including drip 
pans and work areas within facilities covered under this permit.
    18. ``Development Drilling'' means the drilling of wells required 
to efficiently produce a hydrocarbon formation or formations.
    19. ``Development Facility'' means any fixed or mobile structure 
that is engaged in the drilling of productive wells.
    20. ``Diatomaceous Earth Filter Media'' means filter media used to 
filter seawater or other authorized completion fluids and subsequently 
washed from the filter.
    21. ``Diesel Oil'' means the grade of distillate fuel oil, as 
specified in the American Society for Testing and Materials Standard 
Specification D975-81, that is typically used as the continuous phase 
in conventional oil-based drilling fluids.

[[Page 58734]]

    22. ``Director'' means the U.S. Environmental Protection Agency 
Regional Administrator or an authorized representative.
    23. ``Domestic Waste'' means material discharged from galleys, 
sinks, showers, safety showers, eye wash stations, hand washing 
stations, fish cleaning stations, and laundries.
    24. ``Drill Cuttings'' means particles generated by drilling into 
the subsurface geological formations including cured cement carried to 
the surface with the drilling fluid.
    25. ``Drilling Fluids'' means the circulating fluid (mud) used in 
the rotary drilling of wells to clean and condition the hole and to 
counterbalance formation pressure. A water-based drilling fluid is the 
conventional drilling mud in which water is the continuous phase and 
the suspending medium for solids, whether or not oil is present. An oil 
based drilling fluids has diesel oil, mineral oil, or some other oil as 
its continuous phase with water as the dispersed phase.
    26. ``End of well Sample'' means the sample taken after the final 
log run is completed and prior to bulk discharge.
    27. ``Environmental Protection Agency'' (EPA) means the U.S. 
Environmental Protection Agency.
    28. ``Excess Cement Slurry'' means the excess mixed cement, 
including additives and wastes from equipment washdown, after a 
cementing operation.
    29. ``Exploratory Facility'' means any fixed or mobile structure 
that is engaged in the drilling of wells to determine the nature of 
potential hydrocarbon reservoirs.
    30. ``Fecal Coliform Bacteria Sample'' consists of one effluent 
grab portion collected during a 24-hour period at peak loads.
    31. ``Grab sample'' means an individual sample collected in less 
than 15 minutes.
    32. ``Garbage'' means all kinds of food waste, wastes generated in 
living areas on the facility, and operational waste, excluding fresh 
fish and parts thereof, generated during the normal operation of the 
facility and liable to be disposed of continuously or periodically, 
except dishwater, graywater, and those substances that are defined or 
listed in other Annexes to MARPOL 73/78.
    33. ``Graywater'' means drainage from dishwater, shower, laundry, 
bath, and washbasin drains and does not include drainage from toilets, 
urinals, hospitals, and cargo spaces.
    34. ``Inverse Emulsion Drilling Fluids'' means an oil-based 
drilling fluid which also contains a large amount of water.
    35. ``Live bottom areas'' means those areas which contain 
biological assemblages consisting of such sessile invertebrates as seas 
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.
    36. ``Maintenance waste'' means materials collected while 
maintaining and operating the facility, including, but not limited to, 
soot, machinery deposits, scraped paint, deck sweepings, wiping wastes, 
and rags.
    37. ``Maximum Hourly Rate'' means the greatest number of barrels of 
drilling fluids discharged within one hour, expressed as barrels per 
hour.
    38. ``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.
    39. ``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 section 307, 318, 402, 
and 405 of the Act.
    40. ``New Source'' means any facility or activity 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 definitions:
    a. 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.
    b. 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.
    41. ``No Activity Zones'' means those areas identified by the 
Minerals Management Service (MMS) where no structures, drilling rigs, 
or pipelines will be allowed. Those zones are identified as lease 
stipulations in U.S. Department of Interior, MMS, August, 1990, 
Environmental Impact Statement for Sales 131, 135, and 137, Western, 
Central, and Eastern Gulf of Mexico. Additional no activity areas may 
be identified by MMS during the life of this permit.
    42. ``Operational waste'' means all cargo associated waste, 
maintenance waste, cargo residues, and ashes and clinkers from 
incinerators and coal burning boilers.
    43. ``Packer Fluid'' means low solids fluids between the packer, 
production string and well casing. They are considered to be workover 
fluids.
    44. ``Priority Pollutants'' means those chemicals or elements 
identified by EPA, pursuant to section 307 of the Clean Water Act and 
40 CFR 401.15.
    45. ``Produced Sand'' means slurried particles used in hydraulic 
fracturing, the accumulated formation sands, and scale particles 
generated during production. Produced sand also includes desander 
discharge from produced water waste stream and blowdown of water phase 
from the produced water treating system.
    46. ``Produced Water'' means the 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.
    47. ``Production Facility'' means any fixed or mobile structure 
that is either engaged in well completion or used for active recovery 
of hydrocarbons from producing formations.
    48. ``Sanitary Waste'' means human body waste discharged from 
toilets and urinals.
    49. ``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.
    50. ``Sheen'' means a silvery or metallic sheen, gloss, or 
increased reflectivity, visual color or iridescence on the water 
surface.
    51. ``Source Water and Sand'' means water from non-hydrocarbon 
bearing formations for the purpose of pressure maintenance or secondary 
recovery including the entrained solids.
    52. ``Spotting'' means the process of adding a lubricant (spot) 
downhole to free stuck pipe.
    53. Synthetic Drilling Fluid'' means a drilling fluids which has 
synthetic material as its continuous phase with water as the dispersed 
phase.
    54. ``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

[[Page 58735]]

seaward limit of inland waters, and extending seaward a distance of 
three miles.
    55. ``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.
    56. ``Treatment Chemicals'' means biocides, corrosion inhibitors, 
or other chemicals which are used to treat seawater or freshwater to 
prevent corrosion or fouling of piping or equipement.
    57. ``Uncontaminated Ballast/Bilge Water'' means seawater added or 
removed to maintain proper draft.
    58. ``Uncontaminated Freshwater'' means freshwater which is 
discharged without the addition of chemicals; included are (1) 
discharges of excess freshwater that permit the continuous operation of 
fire control and utility lift pumps, (2) excess freshwater from 
pressure maintenance and secondary recovery projects, (3) water red 
during training and testing of personnel in fire protection, and (4) 
water used to pressure test new piping.
    59. ``Uncontaminated Seawater'' means seawater which is returned to 
the sea without the addition of chemicals. Included are (1) discharges 
of excess seawater which permit the continuous operation of fire 
control and utility lift pumps (2) excess seawater from pressure 
maintenance and secondary recovery projects (3) water red during the 
training and testing of personnel in fire protection (4) seawater used 
to pressure test piping, and (5) once through noncontact cooling water 
which has not been treated with biocides.
    60. ``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.
    61. ``Well Treatment Fluids'' mean 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.
    62. ``Workover Fluids'' mean salt solutions, weighted brines, 
polymers, and other specialty additives used in a producing well to 
allow safe repair and 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.
    63. The term ``MGD'' shall mean million gallons per day.
    64. The term ``mg/l'' shall mean milligrams per liter or parts per 
million (ppm).
    65. The term ``ug/l'' shall mean micrograms per liter or parts per 
billion (ppb).

          Table 1-A.--Critical Dilutions (Percent Effluent) for Toxicity Limitations for Seawater to Which Treatment Chemicals Have Been Added
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                 Pipe diameter
          Depth difference** (meters)                  Discharge rate (bbl/day)       ------------------------------------------------------------------
                                                                                         >0'' to 2''      >2'' to 4''      >4'' to 6''         >6''
--------------------------------------------------------------------------------------------------------------------------------------------------------
0 to 5........................................  0 to 1,000...........................             15.6             19.4            6.15             15.4
                                                >1,000 to 10,000.....................             22.6             29.5          *10.3              56
                                                >10,000..............................  ...............             31             46.3              46
>5 to 10......................................  0 to 1,000...........................             15.3             33             59                10.3
                                                >1,000 to 10,000.....................             11.2             25             44                73.3
                                                >10,000..............................  ...............             24.7           39.6              78
>10 to 20.....................................  0 to 1,000...........................             15               32.4           56.5            * 12.3
                                                >1,000 to 10,000.....................             11.3             25             40                56.5
                                                >10,000..............................  ...............             22.6           36.2              57
>20...........................................  0 to 1,000...........................             16.3             33             57              * 10.7
                                                >1,000 to 10,000.....................             11.6             25.6           39.6              57.8
                                                >10,000..............................  ...............             22.6           36.6              51
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Those critical dilutions which are followed by an asteric are required to be monitored using a chronic test.
** Depth Difference means the distance in water depth between the discharge pipe and the seafloor.


         Table 1-B.-- Critical Dilutions (Percent Effluent) for Toxicity Limitations for Freshwater to Which Treatment Chemicals Have Been Added
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                 Pipe diameter
          Depth difference  (meters)                  Discharge rate (bbl/day)       -------------------------------------------------------------------
                                                                                        >0'' to 2''      >2'' to 4''      >4'' to 6''          >6''
--------------------------------------------------------------------------------------------------------------------------------------------------------
All..........................................  0 to 1,000...........................              7.2              8.2             17.4             18
                                               >1,000 to 10,000.....................             17               76             * 11.4           * 13.1
                                               >10,000..............................  ...............             64               93             * 18
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Those critical dilutions which are followed by an asteric are required to be monitored using a chronic test.


[[Page 58736]]


                                        Table 2.--Effluent Limitations, Prohibitions and Monitoring Requirements
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                              Monitoring requirement
                                    Regulated and monitored     Discharge limitation/   ----------------------------------------------------------------
            Discharge                 discharged parameter           prohibition              Measurement
                                                                                               frequency        Sample type method    Recorded value(s)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Drilling Fluids..................  Free Oil.................  No free oil..............  Onceweek(*1)........  Static sheen........  Number of days
                                                                                                                                      sheen observed.
                                   Toxicity(*2) 96-hr LC50..  30,000 ppm daily minimum.  Once/month..........  Grab................  96-hr LC50.
                                                              30,000 ppm monthly         Once/end well(*3)...  Grab................  96-hr LC50.
                                                               average minimum.
                                                                                         Once/month..........  Grab................  96-hr LC50.
                                   Discharge Rate...........  1,000 barrels/hour.......  Once/hour(*1).......  Estimate............  Max hourly rate.
                                   Discharge Rate for         (*4).....................  Once/hour(*1).......  Measure.............  Max hourly rate.
                                    controlled discharge
                                    rate areas.
                                   Mercury and cadmium......  No discharge of drilling   Once prior to         Absorption Spectro-   mg mercury/kg
                                                               fluids to which barite     drilling each well    photometry.           barite.
                                                               has been added, if such    (*6).                                      mg cadmium/kg
                                                               barite contains mercury                                                barite.
                                                               in excess of 1.0 mg/kg
                                                               or cadmium in excess of
                                                               3.0 mg/kg (dry weight).
                                   Oil Based or Inverse       No discharge.............
                                    Emulsion Drilling Fluids.
                                   Oil Contaminated Drilling  No discharge.............
                                    Fluids.
                                   Diesel Oil...............  No discharge of drilling
                                                               fluids to which diesel
                                                               oil has been added.
                                   Mineral Oil..............  Mineral oil may be used
                                                               only as a carrier fluid
                                                               (transporter fluid),
                                                               lubricity additive, or
                                                               pill.
Drilling Cuttings................  Free oil.................  No free oil..............  Once/week(*1).......  Static sheen........  Number of days
                                                                                                                                      sheen observed.
                                   Toxicity(*2) 96-hr LC50..  No discharge of cuttings
                                                               generated using drilling
                                                               fluids which exhibit a
                                                               toxicity of less than
                                                               30,000 ppm daily minimum
                                                               or 30,000 ppm monthly
                                                               avg minimum.
                                   Mercury and cadmium......  No discharge of cuttings
                                                               generated using drilling
                                                               fluids to which barite
                                                               has been added, if such
                                                               barite contains mercury
                                                               in excess of 1.0 mg/kg
                                                               or cadmium in excess of
                                                               3.0 mg/kg (dry weight).
                                   Cuttings generated using   No discharge.
                                    Oil Based or Inverse
                                    Emulsion Drilling Fluids.
                                   Cuttings generated using   No discharge.
                                    Oil Contaminated
                                    Drilling Fluids.
                                   Cuttings generated using   No discharge.
                                    drilling fluids to which
                                    Diesel Oil has been
                                    added.
                                   Cuttings generated using   Mineral oil may be used
                                    drilling fluids to which   only as a carrier fluid
                                    Mineral Oil has been       (transporter fluid),
                                    added.                     lubricity additive, or
                                                               pill.
Deck Drainage....................  Free Oil.................  No free oil..............  Once/day (*7).......  Visual sheen........  Number of days
                                                                                                                                      sheen observed.
Produced Sand....................  No Discharge.
Well treatment fluids, completion  Free oil.................  No free oil..............  Once/Day (*1).......  Static sheen........  Number of days
 fluids, and workover fluids                                                                                                          sheen observed.
 (includes packer fluids) (*10).

[[Page 58737]]

                                   Oil and Grease...........  42 mg/l daily max.,......  Once/month..........  Grab (*8)...........  Daily max, monthly
                                                              29 mg/l monthly avg.                                                    average.
Sanitary waste (*12) continuously  Residual chlorine (*13)..  1 mg/l (minimum).........  Once/month..........  Grab................  Concentration.
 manned by 10 or more persons.
                                   Solids...................  No Floating Solids.......  Once/Day............  Observation(*15)....  Number of days
                                                                                                                                      solids observed.
Sanitary waste (*12) continuously  Solids...................  No floating solids.......  Once/day............  Observation (*15)...  Number of days
 manned by 9 or fewer persons or                                                                                                      solids observed.
 intermittently by any number.
Domestic waste (*14).............  Solids...................  No floating solids or      Once/day............  Observation(*15)....  Number of days
                                                               foam.                                                                  observed.
Miscellaneous discharges:          Free oil.................  No free oil..............  Once/week (*11).....  Visual sheen........  Number of days
 Desalinization unit discharge;                                                                                                       sheen observed.
 blowout pre-venter fluid;
 uncontaminated ballast water;
 uncontaminated bilge water;
 uncontaminated freshwater; mud,
 cuttings and cement at seafloor;
 uncontaminated seawater; boiler
 blow-down; source water and
 sand; diatomaceous earth filter
 media; excess cement slurry.
Miscellaneous discharges of        Treatment chemicals......  Most stringent of: EPA
 seawater and freshwater to which                              label registration,
 treatment chemicals have been                                 maximum manufacturers
 added: excess seawater which                                  recommended dose, or 500
 permits the continuous operation                              mg/l.
 of fire control and utility lift
 pumps, excess seawater from
 pressure maint. and secondary
 recovery prjcts, water red
 during training of personnel in
 fire protection, seawater used
 to pressure test new piping and
 new pipelines, ballast water,
 once-through non-contact cooling
 water, desalinization unit.
                                   Free oil.................  No free oil..............  1/Week..............  Visible sheen.......  Number of days
                                                                                                                                      sheen observed.
                                   Toxicity.................  48-hour average min NOEC   Rate Dependent (*17)  Grab................  Lowest NOEC
                                                               and monthly avg minimum                                                observed for
                                                               NOEC (*5).                                                             either of the two
                                                                                                                                      species.
--------------------------------------------------------------------------------------------------------------------------------------------------------
*1 When discharging.
*2 Suspended particulate phase (SPP) with Mysidopsis bahia following approved test method. The sample shall be taken beneath the shale shaker; or if
  there are no returns across the shaker then the sample must be taken from a location that is characteristic of the overall mud system to be
  discharged.
*3 Sample shall be taken after the final log run is completed and prior to bulk discharge.
*4 See Part I.B.1.b of this permit.
*5 See Appendix A, Table 1 of this permit.
*6 Analyses shall be conducted on each new stock of barite used.
*7 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.
*8 May be based on the arithmetic average of four grab sample results in a 24 hr. period.
*10 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.

[[Page 58738]]

*11 When discharging for muds, cuttings, and cement at the seafloor and blowout preventer fluid. All other miscellaneous discharges: when discharging,
  discharge is authorized only during times when visual sheen observation is possible, unless the static sheen method is used. Uncontaminated seawater
  uncontaminated freshwater, source water and source sand, uncontaminated bilge water, and uncontaminated ballast water from platforms on automatic
  purge systems may be discharged without monitoring from platforms which are not manned.
*12 Any facility which 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.
*13 Hach method CN-66 DPD approved. Minimum of 1 mg/l and maintained as close to this concentration as possible.
*14 The discharge of food waste is prohibited within 12 nautical miles from nearest land. Comminuted food waste able to pass through a 25 mm mesh screen
  (approximately 1 inch) may be discharged more than 12 nautical miles from nearest land.
*15 Monitoring shall be accomplished during daylight by visual observation of the surface of the receiving water in the vicinity of sanitary and
  domestic waste outfalls. Observations shall be made following either the morning or midday meals at a time of maximum estimated discharge.
*16 Once/year for discharges from 0 bbl/day to 4599 bbl/day, once/calendar quarter for discharges of 4,600 bbl/day and greater.
*17 See Part I.B.1.1b of this permit.

[FR Doc 98-29307 Filed 10-30-98; 8:45 am]
BILLING CODE 6560-50-P