[Federal Register Volume 66, Number 50 (Wednesday, March 14, 2001)]
[Notices]
[Pages 14988-14999]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-6175]



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Part II





Environmental Protection Agency





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Final Modification of the National Pollutant Discharge Elimination 
System (NPDES) General Permit for the Eastern Portion of the Outer 
Continental Shelf (OCS) of the Gulf of Mexico (GMG280000); Notice

  Federal Register / Vol. 66, No. 50 / Wednesday, March 14, 2001 / 
Notices  

[[Page 14988]]


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ENVIRONMENTAL PROTECTION AGENCY

[FRL-6944-5]


Final Modification of the National Pollutant Discharge 
Elimination System (NPDES) General Permit for the Eastern Portion of 
the Outer Continental Shelf (OCS) of the Gulf of Mexico (GMG280000)

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of final modification of NPDES general permit for the 
Eastern Portion of the Outer Continental Shelf (OCS) of the Gulf of 
Mexico (GMG2800000).

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SUMMARY: The Regional Administrator (RA) of EPA, Region 4 (Region 4), 
is today providing notice of final modification of the National 
Pollutant Discharge Elimination System (NPDES) general permit for the 
OCS of the Gulf of Mexico (General Permit No. GMG280000) for discharges 
in the Offshore Subcategory of the Oil and Gas Extraction Point Source 
Category (40 CFR part 435, subpart A) as authorized by section 402 of 
the Clean Water Act (``CWA'' or the ``Act''), 33 U.S.C. 1342. The 
existing general permit, issued by Region 4, and published at 63 FR 
55718, October 16, 1998, authorizes discharges from exploration, 
development, and production facilities located in and discharging to 
all Federal waters of the Eastern Gulf of Mexico seaward of the outer 
boundary of the territorial seas.
    This permit modification is in accordance with a settlement entered 
into by EPA with various parties which filed a petition for review of 
the October 16, 1998, general permit in the Fifth Circuit Court of 
Appeals under the caption Marathon Oil Company et al. v. Browner, Civ. 
99-60090. After the permit was issued, and aside from other provisions 
within the permit which specify that any operator authorized by the 
permit may request to be excluded from coverage and receive an 
individual permit pursuant to 40 CFR 122.28(a)(4)(iii), EPA determined 
that the method for calculating effluent limitations and monitoring 
requirements for produced water discharges that appear as part I.B.3 in 
the permit are not appropriate for coverage under a general permit in 
the manner set forth in the October 16, 1998, general permit. The 
intent of this modification is to establish a table of critical 
dilution concentrations for use in determining toxicity limitations. 
Those permittees that have produced water discharges that would fall 
outside of the limits of the modified permit may use a diffuser to 
achieve allowable critical dilution concentrations, or to apply for and 
receive individual NPDES permits.
    The following provides notice of the final modification of the 
general permit including responses to comments. Modifications include: 
changing the general permit numerical designation; requiring permittees 
to indicate what type of effluents the facility is expected to 
discharge within the written notification of intent; allowing approval 
of a shorter notice to drill (NTD) notification period in certain 
circumstances; inclusion of a new table to be used by those permittees 
discharging produced water to calculate the critical dilution 
concentration, or the option of using a diffuser to increase mixing; 
and the addition of limitations and monitoring requirements for those 
permittees discharging chemically treated freshwater or seawater or 
condensation as a result of production processes. Any operator seeking 
coverage under the general permit may be subject to some or all of the 
modifications.
    Finally, EPA also is providing today some additional clarifications 
and minor corrections of existing general permit language based upon 
questions and comments received by the Agency subsequent to the 
original permit issuance and draft modification. This revision is 
discussed in detail later in this document.

DATES: This general permit modification shall become effective on March 
14, 2001.

ADDRESSES: The complete administrative record is available from the 
United States Environmental Protection Agency, Region 4; Freedom of 
Information Officer; Atlanta Federal Center; 61 Forsyth St. S.W.; 
Atlanta, GA 30303-3104. A reasonable fee may be charged for copying.

FOR FURTHER INFORMATION CONTACT: Mr. William Truman, Environmental 
Scientist, telephone number (404) 562-9457, or at the following 
address: United States Environmental Protection Agency, Region 4; Water 
Management Division; NPDES and Biosolids Permits Section; Atlanta 
Federal Center; 61 Forsyth Street S.W.; Atlanta, GA 30303.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Introduction
II. Coverage of General Permit
III. Changes from the August 8, 2000 Proposed General Permit 
Modifications (65 FR 48503)
IV. Summary of Responses to Comments on the Proposed Permit
V. Cost Estimate
VI. Unfunded Mandates Reform Act
VII. Paperwork Reduction Act
VIII. Regulatory Flexibility Act (RFA), as Amended by the Small 
Business Regulatory Enforcement Fairness Act of 1996 (SBREFA), 5 
U.S.C. 601 et seq.

I. Introduction

    In 1972, section 301(a) of the Federal Water Pollution Control Act 
(also referred to as the Clean Water Act) was amended to provide that 
the discharge of any pollutants to waters of the United States (U.S.) 
from any point source is unlawful, except if the discharge is in 
compliance with an NPDES permit.
    On October 16, 1998 (63 FR 55718), Region 4, issued a general 
permit for discharges of pollutants from exploration, development, and 
production facilities located in all Federal waters of the Eastern Gulf 
of Mexico seaward of the outer boundary of the territorial seas. The 
previous permit (July 9, 1986, reissued by Region 4 in 1991) was issued 
jointly by Region 4 and Region 6. Region 6 subsequently, reissued a 
permit in 1992 and 1999 for the Western Portion of the Outer 
Continental Shelf (Western Planning Area).
    For consistency, Region 4, developed a permit similar to those 
issued by Region 6, taking into account any site-specific 
considerations. Both Regions adopted the same method of determining 
produced water toxicity limitations using the Cornell Mixing Zone 
Expert System (CORMIX) to calculate critical dilutions. However, 
information from the vast number of operating facilities in the Western 
Planning Area as compared to the relatively few operating facilities in 
the Eastern Planning Area, enabled Region 6 to develop model input 
parameters based upon information from a large number of operating 
facilities. Region 6 also was able to develop a series of critical 
dilution tables based upon this information and critical dilution 
tables for a large segment of potential permittees were developed and 
included within the Region 6 general permit.
    In this modification, EPA is publishing critical dilution tables as 
part of the general permit, such as those used in Region 6's general 
permit. Due to the fact that fewer than 30 produced water dischargers 
exist in Region 4's permit coverage area, Region 4 elected to model the 
toxicity limitations using the range of data gathered from the 
operators within this area. Region 4 believes this approach will 
include all the expected permittees and will avoid the significant 
resource demands that would have been required to support a

[[Page 14989]]

critical dilution table for the ranges used by Region 6. The derivation 
of critical dilution tables on the scale of those developed by Region 6 
would have required over 200 runs of the CORMIX model just to generate 
ranges that take into account the variations in discharge flow rate, 
discharge pipe diameter, and distance from the pipe to the sea floor. 
Currently, EPA is unaware of any facilities in Region 4's area which 
fall outside of the critical dilution tables in today's final general 
permit. The small number of potential permittees did not justify the 
expenditure of available resources to produce numerous tables.
    EPA, Region 4, has modified this general permit by including a 
critical dilution table comparable to those utilized by the Region 6 
general permit. In accordance with 40 CFR 122.28(3)(i) and (c)(1), any 
owner or operator with a facility with produced water effluent will be 
required to meet the critical dilution values within the limits of the 
modified permit, or to apply for and obtain an individual permit in 
order to discharge into U.S. waters. Existing discharges of produced 
water shall continue to be authorized under the administratively 
extended 1986 general permit, if an individual permit application is 
received within 120 days of the effective date of the permit 
modification. The 1986 general permit coverage shall automatically 
terminate on the date final action is taken on the individual NPDES 
permit application.
    Additionally, EPA has received numerous requests from the regulated 
community regarding the need of a NPDES permit for the discharge of 
fluids used in the hydrostatic testing of pipelines. These fluids 
primarily consist of seawater, biocides, corrosion inhibiting solvents 
(CIS), and other treatment chemicals. The Region 6 general permit 
addresses this activity under miscellaneous discharges with prescribed 
limits on chemical concentration and toxicity. For consistency, Region 
4, has modified the general permit to include effluent limitations and 
monitoring requirements for chemically treated seawater and freshwater.
    EPA, Region 4, will include an additional requirement for 
submitting an Notice of Intent (NOI). Under paragraph (4), part I.4., 
Notification Requirements (Existing Sources and New Sources), the 
permittee shall provide information on the types of discharges expected 
along with data regarding outfall locations.
    In addition, to further distinguish permits issued under this 
general permit from those previously issued by Regions 4 and 6, Region 
4 proposes to modify the general permit number to include an alpha 
character in the 6th position. Permit coverage has been assigned as 
GMG28A001-A999, GMG28B001-B999, GMG28C001-C999, etc. The permit numbers 
for operations currently covered by this permit will change to reflect 
the new system.

II. Coverage of General Permit

    Section 301(a) of the CWA provides that the discharge of pollutants 
is unlawful, except in accordance with the terms of an NPDES permit. 
The EPA has determined that oil and gas facilities seaward of the 200 
meter water depth in certain parts of the Eastern Portion of the Gulf 
of Mexico as described in the NPDES general permit are more 
appropriately controlled by a separate general permit, individual 
permits, or both, 40 CFR 122.28(c). This determination covers both 
existing sources and new sources. This decision is based on the Federal 
regulations at 40 CFR 122.28, 40 CFR part 125 (Subpart M--Ocean 
Discharge Criteria); the Environmental Impact Statement; and the 
Agency's previous decisions in other areas of the Gulf of Mexico's OCS. 
As in the case of individual permits, noncompliance with any condition 
of a general permit constitutes an enforceable violation of the Act 
under section 309 of the Act.
    With this permit modification, all lease blocks with operating 
facilities discharging produced water are required to meet the critical 
dilution limitations allowed under the modified permit, or to apply for 
and obtain individual permits in order to discharge into waters of the 
U.S. This notice will also clarify and correct certain aspects of the 
general permit issued on October 16, 1998.

III. Changes From the August 8, 2000 Proposed General Permit 
Modifications (65 FR 48503)

     Permittees are now required to submit a NTD within 
fourteen (14) days after the drilling rig moves on location.
     Produced water toxicity limitation calculation is further 
clarified. Produced water discharges must meet the limiting permissible 
concentration (LPC) at the edge of a 100 meter mixing zone. The LPC is 
defined as 0.1 times the LC50. The LPC must be equal to or 
greater than the predicted effluent concentration at the edge of a 100 
meter mixing zone. Predicted effluent concentrations, referred to as 
``Critical Dilutions,'' are presented in Table 4- and Table 4-A for a 
range of discharge rates and pipe diameters.
     Permittees wishing to increase mixing may use a diffuser 
to meet critical dilution limitations. Permittees shall submit a 
certification that the diffuser, seawater addition, or multiple 
discharge ports has been installed and state the critical dilution and 
corresponding LC50 in the certification. The CORMIX2 model 
runs shall be retained by the permittee as part of its NPDES records.
     The 403(c) Reopener clause has been deleted.
     The critical dilutions for toxicity limitations for the 
discharge of freshwater and seawater to which chemicals have been added 
shall be determined using Tables 5-A or 5-B. These tables were in the 
preamble, but omitted from the draft permit modification.
     Species and test methods for performing the required 
toxicity test for chemically treated freshwater and saltwater has been 
added.
     Two new definitions have been added to Part IV.B., for 
condensation water and Eastern Portion of the Gulf of Mexico. The 
numbering of the definitions was also corrected.

IV. Summary of Responses to Comments on the Proposed Permit

    Public notice of the draft permit modification was published at 65 
FR 48503 (August 8, 2000) with a notice to consider holding public 
hearings on the Region's proposal, if requests for such hearings were 
received. No requests for public hearings were received. Copies of 
comments received during this action from interested parties have been 
considered in a formulation of a final determination regarding Region 
4's final action today on the modification of NPDES Permit No. 
GMG280000. A summary of the permit related comments are summarized 
below.

Summary of Permit Preamble Related Comments

    Comment 1: Commenter makes numerous comments in regards to the 
addition of chemically treated freshwater and seawater to the category 
of ``Miscellaneous Discharges.''
    Response: EPA agrees with the commenter's editorial comment and has 
made the corresponding revision to the preamble in the permit.

Summary of Permit Modification Related Comments

    Comment 2: Commenter has stated that there may be a confusion of 
terms regarding the use of Western, Central, and Eastern Planning 
Areas, and the Western and Eastern Gulf of Mexico. The Planning Areas 
are Mineral Management Service (MMS) planning tools for lease sales and 
do not have the

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same notation as the Eastern and Western Gulf.
    Response: EPA agrees with the commenter's editorial comment and has 
added a definition to the permit to avoid any confusion. Region 4's 
operational jurisdiction, the Eastern Portion of the Gulf of Mexico, is 
the Federal waters in the Gulf of Mexico seaward of the territorial 
seas of Mississippi, Alabama, and Florida.
    Comment 3: Commenter denotes that certain information regarding the 
history of the general permit and continued permit coverage, though 
discussed in the preamble, is not included in the permit. The proposed 
language is suggested: Authorization to Discharge Under the National 
Pollutant Discharge Elimination System
    ``In accordance with 40 CFR 122.28(b)(3)(i) and (c)(1), any owner 
or operator with a facility with produced water effluent are required 
to meet the critical dilution values within the limits of the table, or 
to apply for and obtain an individual permit in order to discharge into 
U.S. waters. Existing discharges of produced water shall continue to be 
authorized under the administratively extended 1986 general permit, if 
an individual permit application is received within 120 days of the 
effective date of the permit modification. The 1986 general permit 
coverage shall automatically terminate on the date final action is 
taken on the individual NPDES permit application.''
    Response: EPA agrees with the commenter's suggested wording for the 
permit regarding the background of the general permit. EPA has revised 
the language of the permit accordingly.
    Comment 4: Regarding the new permit coverage numbering convention, 
the following clarification language is suggested:
    ``The new numbering convention is, e.g., GMG28A001-A999, GMG28B001-
B999, GMG28C001-C999, etc. For all notices of general permit coverage 
provided since the effective date of the November 16,1998 permit, 
GMG280xxx and GMG289xxx designations shall be changed to GMG28Axxx. The 
last three digits of the assigned permit number will remain the same.''
    Response: EPA agrees with the commenter's suggested wording for the 
permit regarding the numbering for general permit coverage. EPA has 
revised the language of the permit accordingly.
    Comment 5: Stated that EPA should change its proposed 
identification system and use American Petroleum Institute (API) and 
MMS coding system. Stated that MMS will be analyzing Discharge 
Monitoring Reports (DMR) as part of its initiatives to meet the 
requirements of Government and Performance Results Act and to take full 
advantage of the DMR information submitted to EPA, we ask that 
operators link discharge information to discharge locations by using 
API and MMS codes.
    Response: The current structure of EPA data fields does not allow 
the Region the flexibility to implement the American Petroleum 
Institute/Minerals Management Service numbers and currently are not 
amenable to change.
    Comment 6: Commenter states that the site-specific NOI requirements 
dealing with bottom surveys are inappropriate for a general permit and 
should apply only in limited areas.
    Response: EPA believes that in order to provide adequate protection 
to the marine environment, site-specific information is needed to 
determine the types of communities and habitats present at the site of 
discharge. EPA also believes that requiring individual permitting in 
order to obtain such information is unnecessarily time consuming and 
burdensome. EPA agrees that information exists for some areas of 
biological concern to predetermine their locations. However, because 
only a small proportion of the seafloor within either the Central or 
Eastern Planning Areas have been adequately surveyed, EPA believes that 
it cannot be said, with absolute certainty that other areas requiring 
more stringent discharge requirements do not exist. We feel that there 
is sufficient potential for the existence of important biological 
communities in, as of yet, unexplored areas.
    Comment 7: Commenter states that in the submittal of the NOI, the 
location of the ``outfalls'' should be changed to ``facility,'' and the 
added requirement for identifying ``expected discharges'' be deleted. 
By the nature of general permit coverage all listed discharges are 
permitted.
    Response: EPA agrees that coverage under the general permit allows 
a permittee to utilize all listed discharges, however, some of the 
operations will not have a discharge for some of the listed wastewater 
sources. Also, this information will assist EPA in the review of DMR 
data for ``specific discharges.'' EPA believes that the information 
regarding expected discharges may be useful in future studies regarding 
water quality of the Eastern Portion of the Gulf of Mexico and that the 
request does not present an undo burden on the permittee. EPA agrees 
with the commenter's statement about the change in location data from 
``outfall'' to ``facility.''
    Comment 8: In discussing the flexibility in placement of a surface 
location, both 500 feet and 500 meters are used. The commenter wants to 
know if the difference in units is correct or a typographical error.
    Response: A final surface location should be within 500 meters of 
the proposed surface location. An additional photodocumentation survey 
is not required, provided the final location is within 500 meters of an 
area previously surveyed. The difference in units was a typographical 
error.
    Comment 9: Commenter states that in submitting an NOI on a non-
operational or newly acquired lease, an Exploration Plan, Development 
and Production Plan, or Development Operations Coordination Document 
should be first submitted to MMS.
    Response: EPA agrees with the commenter's editorial comment and 
will revise the language in Part I.A.4. accordingly.
    Comment 10: Clarification is provided regarding permit transfers, 
but not included in the permit modification. Suggested language should 
replace Part II.D.3. of the general permit:
    ``Should any new owner or operator notify EPA prior to the transfer 
of operatorship, no additional NOI documentation need be submitted.
    If the facility remains operational, then the NOI by the new 
operator should reference the previously submitted NOI, EPA's 
authorization to proceed, and the assigned permit number. EPA will then 
provide the new operator a notice of inclusion and a newly assigned 
permit number.''
    Response: EPA agrees with the commenter and will provide language 
for the permit regarding the notification of a transfer.
    Comment 11: MMS no longer requires a photodocumentation survey in 
the Central Planning Area in water depths less than 100 meters. MMS 
still requires this documentation in the Eastern Planning Area.
    Response: EPA agrees with the commenter's editorial comment and has 
made the corresponding revision of Part I.A.4(11) in the permit.
    Comment 12: The NTD is provided to make EPA aware that drilling 
activity is taking place. Providing notice to EPA 14 days after the 
drilling rig moves on location provides EPA the information they need 
while eliminating the 60-day administrative burden caused by changing 
rig schedules.
    Response: EPA understands the variations in rig schedules and 
unforeseen conditions that may prevent previous notification of a 
drilling rig's move-on date. EPA agrees with the

[[Page 14991]]

commenter's suggested wording for the permit regarding the NTD and will 
revise the language of the permit accordingly.
    Comment 13: The commenter would like to reduce the amount of 
paperwork needed regarding the re-notification process for continued 
coverage under the general permit after it's expiration.
    Response: EPA disagrees with the commenter's suggested wording. As 
with individual NPDES permits, EPA has determined that continued 
coverage under an expired general permit, if it has not been reissued 
before its expiration date, can only be granted if another NOI is 
submitted prior to the expiration date of the general permit.
    Comment 14: States that the tables developed for produced water 
discharges are too restrictive and should reflect the multiple 
parameters utilized in the Region 6 critical dilution tables for 
produced water.
    Response: Due to the fact that fewer than 30 produced water 
dischargers exist in Region 4's permit coverage area, Region 4 elected 
to model the toxicity limitations using the range of data gathered from 
the operators within this area. Region 4 believed this approach will 
include all the expected permittees and will avoid the significant 
resource demands that would have been required to support a critical 
dilution table for the ranges used by Region 6. The derivation of 
critical dilution tables on the scale of those developed by Region 6 
would have required over 200 runs of the CORMIX model just to generate 
ranges that take into account the variations in discharge flow rate, 
discharge pipe diameter, and distance from the pipe to the sea floor. 
Currently, EPA is unaware of any facilities in Region 4's area which 
fall outside of the proposed critical dilution tables. The small number 
of potential permittees did not justify the expenditure of available 
resources to produce numerous tables.
    In accordance with 40 CFR 122.28(3)(i) and (c)(1), any owner or 
operator with a facility with produced water effluent will be required 
meet the critical dilution values within the limits of the table, or 
CORMIX model, or to apply for and obtain an individual permit in order 
to discharge into U.S. waters.
    Comment 15: Requested further clarification regarding the 
calculation of specific produced water discharge toxicity.
    Response: The Region recognizes the need to provide additional 
clarification regarding the produced water toxicity and will revise the 
language in the permit accordingly.
    Comment 16: The commenter states that the Agency should allow the 
use of diffusers, dilution or split discharges to increase mixing in 
order to achieve compliance with the produced water toxicity 
limitation.
    Response: The permittee determines the produced water toxicity 
limitation based on a facility's site-specific water column conditions 
and discharge configuration. An operator can utilize any number of 
methods to increase the dilution of their wastestream in configuring 
their effluent discharge. The configuration that is ultimately utilized 
must be used to model the facility-specific toxicity limitation. 
Commingling or diluting wastestreams prior to discharging effluent, 
however, cannot be used as a method to achieve NPDES permit compliance. 
EPA agrees with the commenter's suggested wording for the permit 
regarding the use of a diffuser, etc. to meet produced water toxicity 
limitations. EPA has revised the language of the permit accordingly.
    Comment 17: The commenter suggests language to correct the 
frequency at which toxicity tests are required. Tests are required 
every 2 months, rather than monthly.
    Response: EPA agrees with the commenter's suggested wording for the 
permit regarding frequency of toxicity testing. EPA has revised the 
language of the permit accordingly.
    Comment 18: Proposes that the specific use for chemically treated 
freshwater or seawater, that was added to miscellaneous discharges, not 
be restricted to only the hydrostatic testing of new piping and 
pipelines.
    Response: EPA agrees with the commenter's editorial comment and has 
made the corresponding revision to Part I.B. in the permit.
    Comment 19: Proposes the addition of a new waste stream outside of 
the more general ``miscellaneous discharges'' for discharges of 
chemically treated freshwater and seawater. This would separate 
miscellaneous discharges into two categories, e.g., those with 
limitations of no free oil and the stated exception and those with 
limitations of no free oil, the stated exception, treatment chemical 
limitations, toxicity testing, and flow recording.
    Response: EPA agrees with the proposed addition of a separate 
miscellaneous discharge category, and has made the corresponding 
revision to Part I.B. in the permit.
    Comment 20: Tables 5-A and 5-B were mislabeled in the preamble and 
omitted from the permit.
    Response: EPA agrees with the commenter's observation and has made 
the corresponding correction in the permit.
    Comment 21: Additional language proposed to define the species and 
test methods for performing the required toxicity test for chemically 
treated freshwater and seawater. The proposed language is consistent 
with the EPA Region 6 permit.
    Response: EPA agrees with the commenter's suggested wording for the 
permit regarding the toxicity testing for chemically treated freshwater 
and seawater. EPA has revised the language of the permit accordingly.
    Comment 22: Proposed language regarding methods to increase 
dilution for produced water discharges should apply to seawater and 
freshwater that has been chemically treated.
    Response: EPA agrees with the commenter's suggested wording. EPA 
has revised the language of the permit accordingly.
    Comment 23: Commenters have addressed the addition of the 403(c) 
Reopener Clause that was the result of the President's Executive Order 
No. 13158 on Marine Protected Areas dated May 26, 2000. ``The proposed 
403(c) Reopener Clause is in direct contravention of EPA's duly 
promulgated regulations as set forth in 40 CFR 122.62-122.64 and 40 CFR 
125.123. Sections 40 CFR 122.62-122.64 describe the available causes 
for modification or revocation of NPDES permits, of which the proposed 
language is clearly not included. Revocation is only allowable if the 
permittee requests or agrees with it. Furthermore, the proposed 
language is not permissible because it fails to specify that the ``new 
data or requirements'' must not have been available at the time of 
permit issuance, a requirement of 40 CFR 122.62(a)(2).
    In addition, the ocean discharge criteria regulations do not 
provide authority for this provision. The Reopener clause at 40 CFR 
125.123(d)(4) applies if and only if the Director lacks sufficient 
information to determine whether there is unreasonable degradation to 
the marine environment prior to permit issuance. In this case, the 
Director has already made such a finding prior to the general permit 
issuance in October 1998. Therefore, proposed language is not 
applicable. Furthermore, such a Reopener clause relates only to 
``continued discharges'' not ``increased discharges'' and can only be 
based in the case of ``new data,'' not ``new requirements.'' Also, the 
provisions of 40 CFR 125.123(d)(4) do not pertain to ``protecting'' the 
marine environment or ``special aquatic sites.''

[[Page 14992]]

    Additionally, inclusion of such a provision may very well be 
inconsistent with statutory (33 U.S.C. 1316(d)) and regulatory (40 CFR 
122.29(d)) protection afforded by new sources with respect to complying 
with new source performance standards.''
    Response: EPA has addressed the issue regarding the Reopener 
Clause. Alternate permit modification language has been added to Part 
III.B. of the general permit. As future reference, however, pursuant to 
40 CFR Sec. 122.64, EPA may revoke or terminate a permit without the 
permittee's permission.
    Comment 24: Stated that a provision to the permit should be added 
requiring permittees to inform all contractors of the discharge 
limitations of their permit. Particularly important in the case of 
individual permits where discharge limitations may be imposed that are 
more stringent than those of the general permit. It is only fair to 
ensure that contractors are provided with information regarding the 
permit conditions, because of the increasing use of contractors by the 
offshore operating companies who will be the permittees.
    Response: The operator is liable and responsible for the 
information on monitoring requirements and compliance with the 
limitations and conditions within the general permit. If the operator 
feels that a contractor will impact on compliance with the requirements 
of the general permit, then it is incumbent on the operator to bring 
this to the attention of the contractor.
    Comment 25: The commenter feels that a Reopener clause should be 
added to authorize the discharge of drill cuttings from synthetic-based 
drilling mud systems. In the final Coastal Effluent Guidelines, the 
Agency recognized that additional categories of drilling fluids, 
specifically Synthetic Based Mud (SBM) and Enhanced Mineral Oil (EMO), 
were warranted. The Eastern OCS general permit should do the same.
    Response: EPA is aware that the oil and gas industry has developed 
additional drilling fluid types, including synthetic fluid-based muds 
(SBM) and has acknowledged this new technology within the permit. EPA 
Headquarters is currently developing effluent limitations guidelines 
(ELGs) for SBMs. Once the final ELGs are published, EPA Region 4 may 
consider modifying the existing permit to incorporate SBMs per the 
limitations of the guidelines. For this permit, however, SBMs are not 
authorized for discharge. Operators who wish to use SBMs should submit 
an individual permit application.
    Comment 26: Language added to Part III.B. Definitions to define 
``condensation water.''
    Response: EPA agrees with the commenter's editorial comment and 
will insert the following definition for ``condensation water'' as a 
new paragraph (14):
    ``Condensation water means water that is produced as a result of 
condensation during the production process that results in a direct 
discharge without the condensate being used for any other purpose prior 
to discharge.''

V. Cost Estimate

    The cost of compliance with a general permit is lower than that of 
an individual permit. Therefore, there is a comparative financial 
benefit to coverage under the general permit, even with produced water 
requirements, as compared to coverage under an individual permit.

VI. 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. UMRA uses the term ``regulatory actions'' to 
refer to regulations. (See, e.g., UMRA section 201, ``Each agency shall 
* * * assess the effects of Federal regulatory actions * * * (other 
than to the extent that such regulations incorporate requirements 
specifically set forth in law)''). UMRA section 102 defines 
``regulation'' by reference to section 658 of Title 2 of the U.S. Code, 
which in turn defines ``regulation'' and ``rule'' by reference to 
section 601 (2) of the Regulatory Flexibility Act (RFA). That section 
of the RFA defines ``rule'' as ``any rule for which the agency 
publishes a notice of proposed rulemaking pursuant to section 553(b) of 
the Administrative Procedure Act (APA), or any other law * * *''
    NPDES general permits are not ``rules'' under the APA and thus not 
subject to the APA requirement to publish a notice of proposed 
rulemaking. NPDES general permits also are not subject to such a 
requirement under the CWA. While EPA publishes a notice to solicit 
public comments on draft general permits, it does so pursuant to the 
CWA section 402(a) requirement to provide an ``opportunity for a 
hearing.'' Thus, NPDES general permits are not ``rules'' for RFA or 
UMRA purposes.
    Title II of the Unfunded Mandates Reform Act of 1995, Public Law 
104-4, establishes requirements for Federal agencies to assess the 
effects of their regulatory actions on State, local, and Tribal 
governments and the private sector. Under UMRA section 202, EPA 
generally must prepare a written statement, including a cost-benefit 
analysis, for proposed and final rules with ``Federal mandates'' that 
may result in expenditures to State, local, and Tribal governments, in 
the aggregate, or to the private sector, of $100 million or more in any 
one year. Before promulgating an EPA rule for which a written statement 
is needed, UMRA section 205 generally requires EPA to identify and 
consider a reasonable number of regulatory alternatives and adopt the 
least costly, most cost-effective or least burdensome alternative that 
achieves the objectives of the rule. The provisions of UMRA section 205 
do not apply when they are inconsistent with applicable law. Moreover, 
UMRA section 205 allows EPA to adopt an alternative other than the 
least costly, most cost-effective or least burdensome alternative if 
the Administrator publishes an explanation with the final rule why the 
alternative was not adopted.
    EPA has determined that the proposed permit modification would not 
contain a Federal requirement that may result in expenditures of $100 
million or more for State, local and tribal governments, in the 
aggregate, or the private sector in any one year.
    The Agency also believes that the permit would not significantly 
nor uniquely affect small governments. For UMRA purposes, ``small 
governments'' is defined by reference to the definition of ``small 
government jurisdiction'' under the RFA. (See UMRA section 102(1), 
referencing 2 U.S.C. 658, which references section 601(5) of the RFA.) 
``Small governmental jurisdiction'' means government of cities, 
counties, towns, etc. with a population of less than 50,000, unless the 
agency establishes an alternative definition.
    The permit modification would not uniquely affect small governments 
because compliance with the modified permit conditions affects small 
governments in the same manner as any other entities seeking coverage 
under the permit. Additionally, EPA does not expect small government to 
operate facilities authorized to discharge by this permit.

VII. Paperwork Reduction Act

    The information collection required by these permits has been 
approved by the Office of Management and Budget (OMB) under the 
provisions of the PRA, 44 U.S.C. 3501 et seq., in submission made for 
the NPDES permit program and assigned OMB control numbers

[[Page 14993]]

2040-0086 (NPDES permit application) and 2040-0004 (discharge 
monitoring reports).
    EPA did not prepare an Information Collection Request (ICR) 
document for today's permit modification because the information 
collection requirements in this permit have already been approved by 
OMB in submissions made for the NPDES permit program under the 
provisions of the CWA.

VIII. Regulatory Flexibility Act (RFA), as Amended by the Small 
Business Regulatory Enforcement Fairness Act of 1996 (SBREFA), 5 
U.S.C. 601 et seq.

    Today's modified general permit is not subject to the RFA, which 
generally requires an agency to prepare a regulatory flexibility 
analysis for any rule that will have a significant economic impact on a 
substantial number of small entities. The RFA only applies to rules 
subject to notice and comment rulemaking requirements under the APA or 
any other statute. As previously stated, the permit modification 
proposed today is not a ``rule'' subject to the RFA. Although this 
proposed general permit is not subject to the RFA, EPA nonetheless has 
assessed the potential of this rule to adversely impact small entities 
subject to this general permit and, in light of the facts presented 
above, I hereby certify pursuant to the provisions of the RFA that 
these proposed general permit modifications will not have a significant 
impact on a substantial number of small entities. This determination is 
based on the fact that the vast majority of the parties regulated by 
this permit have greater than 500 employees and are not classified as 
small businesses under the Small Business Administration regulations 
established at 49 FR 5024 (February 9, 1984). For those operators 
having fewer than 500 employees, this permit issuance will not have 
significant economic impact. These facilities are classified as Major 
Group 13--Oil and Gas Extraction SIC Crude Petroleum and Natural Gas.

    Authority: Clean Water Act, 33 U.S.C. 1251 et seq.

    Dated: March 2, 2001.
A. Stanley Meiburg,
Acting Regional Administrator, Region 4.

Final Modification of the National Pollutant Discharge Elimination 
System (NPDES) General Permit for the Eastern Portion of the Outer 
Continental Shelf (OCS) of the Gulf of Mexico (GMG280000)

Final Modification of National Pollutant Discharge Elimination System 
(NPDES) General Permit for the Eastern Portion of the Outer Continental 
Shelf (OCS) of the Gulf of Mexico (GMG280000)
    For reasons set forth in the preamble, the NPDES General Permit for 
the Eastern Portion of the Outer Continental Shelf (OCS) of the Gulf of 
Mexico (GMG280000) (63 FR 55718-55762, October 16, 1998) is modified as 
described below. EPA has deleted Appendix A from the general permit 
along with several other additional modifications and clarifications. 
These modifications will become effective on the date of Federal 
Register publication of the modifications.

General Permit Number [Modification]

    (1) As of the effective date of the Federal Register publication of 
these modifications, the general permit number, originally identified 
as GMG280000, is modified to read as GMG28AXXX, where the 6th 
significant figure will carry an alphabetic designation. The new 
numbering convention is, e.g., GMG28A001-A999, GMG28B001-B999, 
GMG28C001-C999, etc. For all notices of general permit coverage 
provided since the effective date of the November 16, 1998 permit, 
GMG280xxx and GMG289xxx designations shall be changed to GMG28Axxx.
    (2) On page 55746, the next to the last paragraph is no longer 
applicable and is replaced with a new paragraph to provide additional 
information as follows:

Authorization to Discharge Under the National Pollutant Discharge 
Elimination System

    In accordance with 40 CFR 122.28(b)(3)(i) and (c)(1), any owner 
or operator with a facility with produced water effluent is required 
to meet the critical dilution values within the limits of the 
modified permit, or approved CORMIX modeling, or to apply for and 
obtain an individual permit in order to discharge into U.S. waters. 
Existing discharges of produced water shall continue to be 
authorized under the administratively extended 1986 general permit, 
if an individual permit application is received within 120 days of 
the effective date of the permit modification. The 1986 general 
permit coverage shall automatically terminate on the date final 
action is taken on the individual NPDES permit application.

Part I. Requirements for NPDES Permits

    (3) On page 55747, paragraph 4 is modified to add additional 
information requirements and corrected to update the technical 
references, as follows:

Section A. Permit Applicability and Coverage Conditions

4. Notification Requirements (Existing Sources and New Sources)

    Written notification of intent (NOI) to be covered in accordance 
with the general permit requirements shall state whether the 
permittee is requesting coverage under the existing source general 
permit or new source general permit and shall contain the following 
information:
    (1) The legal name and address of the owner or operator;
    (2) The facility name and location, including the lease block 
assigned by the Department of Interior, or if none, the name 
commonly assigned to the lease area;
    (3) The number and type of facilities and activity proposed 
within the lease block;
    (4) The waters into which the facility is or will be 
discharging; including a map with longitude and latitude of facility 
location and expected discharges identified by the nomenclature used 
in Part I., section B.1-11. Additional information may be requested 
by the Director regarding miscellaneous discharges.
* * * * *
    (10) Technical information on the characteristics of the sea 
bottom in accordance with MMS Notice To Lessees 98-20, Shallow 
Hazard Requirements, or the most current MMS guidelines for shallow 
hazard investigation and analysis.''
    (11) MMS live bottom survey in accordance with MMS Notice To 
Lessees 99-G16 Live-Bottom Surveys and Reports, or the most current 
MMS guidelines for live-bottom surveys and reports.
* * * * *
    (4) On page 55747, paragraph 4, is corrected to clarify NOI 
notification requirements for a newly acquired lease as follows:

    For operating leases, the NOI shall be submitted within sixty 
(60) days after publication of the final determination on this 
action. Non-operational facilities are not eligible for coverage 
under these new general permits. No NOI will be accepted from either 
a non-operational or newly acquired lease until such time as an 
exploration plan or development production plan has been prepared 
and submitted to MMS.
* * * * *

    (5) On page 55747, paragraph 4, is modified regarding NTD notice 
requirements and clarified to update the Agency address for submission 
of notices under the general permit follows:

    For drilling activity, the operator shall submit a Notice to 
Drill (NTD) within

[[Page 14994]]

fourteen (14) days after the drilling rig moves on location. This 
NTD shall contain: (1) The assigned NPDES general permit number 
assigned to the facility, (2) the latitude and longitude of the 
facility, (3) the water depth, and (4) the estimated length of time 
the drilling operation will last. This NTD shall be submitted to 
Region 4 at the address above, by certified mail to: Director, Water 
Management Division; NPDES and Biosolids Permit Section; U.S. EPA, 
Region 4; Atlanta Federal Center; 61 Forsyth Street, S.W.; Atlanta, 
GA 30303-8960.
* * * * *
    All NOIs, NTDs, NCOs, and any subsequent reports required under 
this permit shall be sent by certified mail to the following 
address: Director, Water Management Division; NPDES and Biosolids 
Permits Section; U.S. EPA, Region 4; Atlanta Federal Center; 61 
Forsyth Street, S.W.; Atlanta, GA 30303-8960.
* * * * *
    (6) On page 55747, paragraph 4, is modified to remove the reference 
to Appendix A and corrected to remove two typographical errors as 
follows:

    In addition, a notice of commencement of operations (NCO) is 
required to be submitted for each of the following activities: 
placing a production platform in the general permit coverage area 
(within 30 days after placement); and discharging produced water 
within the coverage area.

6. Intent To Be Covered by a Subsequent Permit

    (7) On page 55747, paragraph 6, is clarified to update the Agency 
address for submission of notices under the general permit follows:

    This permit shall expire on October 31, 2003. However, an 
expired general permit continues in force and effect until a new 
general permit is issued. Lease block operators authorized to 
discharge by this permit shall by certified mail notify the 
Director, Water Management Division; NPDES and Biosolids Permit 
Section; U.S. EPA, Region 4; Atlanta Federal Center; 61 Forsyth 
Street, S.W.; Atlanta, GA 30303-8960, on or before April 30, 2003, 
that they intend to be covered by a permit that will authorize 
discharge from these facilities after the termination date of this 
permit on October 31, 2003.
    Permittees must submit a new NOI in order to continue coverage 
under this general permit after it expires. In lieu of providing the 
information required by paragraph 4. of this section, the permittee 
may submit a list of facilities covered by the general permit and 
their associated permit coverage numbers. Facilities that have not 
submitted an NOI under the permit by the expiration date cannot 
become authorized to discharge under any continuation of this NPDES 
general permit. All NOI's from permittees requesting coverage under 
a continued permit should be sent by certified mail to: Director, 
Water Management Division; NPDES and Biosolids Permits Section; U.S. 
EPA, Region 4; Atlanta Federal Center; 61 Forsyth Street, S.W.; 
Atlanta, GA 30303-8960.

    (8) On page 55749, Section B, paragraph 3 is modified to remove the 
reference to Appendix A, correct the arithmetic formula regarding 
limiting permissible concentrations, correct the reporting requirement 
for oil and grease limitation, and referencing the new produced water 
critical dilution tables, as follows:

Section B. Effluent Limitations and Monitoring Requirements

3. Produced Water

    (b) Limitations. Oil and Grease. Produced water discharges must 
meet both a daily maximum limitation of 42 mg/l and a monthly 
average limitation of 29 mg/l for oil and grease. A grab sample must 
be taken at least once per month. The daily maximum samples may be 
based on the average concentration of four grab samples taken within 
the 24-hour period. If only one sample is taken for any one month, 
it must meet both the daily and monthly limits. If more samples are 
taken, they may exceed the monthly average for any one day, provided 
that the average of all samples taken meets the monthly limitation. 
The gravimetric method is specified at 40 CFR part 136. The highest 
daily maximum oil and grease concentration and the monthly average 
concentration shall be reported on the monthly DMR.
    Toxicity. Produced water discharges must meet the limiting 
permissible concentration (LPC) at the edge of a 100 meter mixing 
zone. The LPC is defined as 0.1 times the LC50. The LPC 
must be equal to or greater than the predicted effluent 
concentration at the edge of a 100 meter mixing zone. Predicted 
effluent concentrations, referred to as ``Critical Dilutions,'' are 
presented in Table 4- and Table 4-A for a range of discharge rates 
and pipe diameters. Critical dilution shall be determined using 
Tables 4 and 4-A of this permit based on the discharge rate most 
recently reported on the discharge monitoring report, discharge pipe 
diameter, and water depth between the discharge pipe and the bottom. 
Facilities which have not previously reported produced water flow on 
the discharge monitoring report shall use the highest monthly 
average flow measured during the previous twelve months for 
determining the critical dilution from Tables 4 and 4-A of this 
permit. LC50 shall be calculated by conducting 96-hour 
toxicity tests every 2 months using Mysidopsis bahia and inland 
silverside minnow.
    (Exception) Permittees wishing to increase mixing may use a 
horizontal diffuser, add seawater, or may install multiple discharge 
ports. Permittees using increased mixing shall install the system 
such that the 96-hour LC50 limit is equal to or greater 
than 10 times the critical dilution (LC50 = 10  x  
critical dilution). The projected percent effluent (critical 
dilution) at the edge of the 100 meter mixing zone will be 
calculated using CORMIX2, with the following input conditions:

Density gradient = 0.163 kg/m\3\/m
Ambient seawater density at diffuser depth = 1023.0 kg/m\3\
Produced water density = 1070.2 kg/m\3\
Current speed = 5 cm/sec (200 m); 15 cm/sec (>200m)

    Permittees shall submit a certification that the diffuser, 
seawater addition, or multiple discharge ports has been installed 
and state the critical dilution and corresponding LC50 in 
the certification. The CORMIX2 model runs shall be retained by the 
permittee as part of its NPDES records. Permittees using vertical 
aligned multiple discharge ports shall provide vertical separation 
between ports. When multiple discharge ports are installed, the 
depth difference between the discharge port closest to the seafloor 
and the seafloor shall be the depth difference used as the parameter 
to determine critical dilution. The critical dilution value shall be 
based on the port flow rate (total flow divided by the number of 
discharge ports) and based on the diameter of the discharge port (or 
smallest discharge port, if they are different styles).
    When seawater is added to produced water prior to discharge, the 
total produced water flow, including the added seawater, shall be 
used in determining the critical dilution.
* * * * *
    (9) On page 55749, paragraph 7 is modified to further define the 
exemption for sanitary waste discharges, as follows:

7. Sanitary Waste (Facilities Continuously Manned by 10 or More 
Persons)

    (b) Limitations. Residual Chlorine. Total residual chlorine is a 
surrogate parameter for fecal coliform. Discharges of sanitary waste 
must contain a minimum of 1 mg residual chlorine/l and shall be 
maintained as close to this concentration as possible. The approved 
analytical method is Hach CN-66-DPD. A grab sample must be taken 
once per month and the concentration reported.
    (Exception) Any facility which properly 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 annually for proper operation and the test 
results maintained at the facility. The operator shall indicate use 
of an MSD on the monthly DMR.
* * * * *
    (10) On page 55750, paragraph 8 is modified to further define the 
exemption for sanitary waste discharges, as follows:

8. Sanitary Waste (Facilities Continuously Manned by 9 or Fewer Persons 
or Intermittently by Any Number)

    (a) Prohibitions. Solids. No floating solids may be discharged 
to the receiving waters. An observation must be made once per day 
when the facility is manned, during daylight in the vicinity of 
sanitary waste outfalls, following either the morning or midday meal 
and at a time during maximum estimated discharge. The number of days 
solids are observed shall be recorded.
    (Exception) Any facility which properly operates and maintains a 
marine sanitation device (MSD) that complies with pollution control 
standards and regulations under

[[Page 14995]]

section 312 of the Act shall be deemed in compliance with permit 
limitations for sanitary waste. The MSD shall be tested annually for 
proper operation and the test results maintained at the facility. 
The operator shall indicate use of an MSD on the monthly DMR.
* * * * *
    (11) On page 55750, paragraph 10 is modified to include additional 
defined ``miscellaneous discharges.'' as follows:

    10. Miscellaneous Discharges. Desalination Unit Discharge; 
Blowout Preventer Fluid; Uncontaminated Ballast Water; 
Uncontaminated Bilge Water; Mud, Cuttings, and Cement at the 
Seafloor; Uncontaminated Seawater; Boiler Blowdown; Source Water and 
Sand; Uncontaminated Freshwater; Excess Cement Slurry; Diatomaceous 
Earth Filter Media; and waters resulting from condensation.
* * * * *
    (12) On page 55750, paragraph 11 is added to include additional 
effluent limitations and monitoring requirements for the miscellaneous 
discharge of chemically treated freshwater and seawater, as follows:

    11. Miscellaneous discharges of Freshwater and Seawater which 
have been chemically treated.
    The discharge of freshwater and seawater to which chemicals have 
been added shall be limited and monitored by the permittee as 
specified in Tables 2 and 3 and as below.
    (a) Free Oil. No free oil shall be discharged. Monitoring shall 
be performed using the visual sheen test method once per day when 
discharging on the surface of the receiving water or by use of the 
static sheen method at the operator's option. Both tests shall be 
conducted in accordance with the methods presented at IV.A.3 and 
IV.A.4. Discharge is limited to those times that a visual sheen 
observation is possible. The number of days a sheen is observed must 
be recorded.
    (Exception): Miscellaneous discharges may be discharged from 
platforms that are on automatic purge systems without monitoring for 
free oil when the facility is not manned. Discharge is not 
restricted to periods when observation is possible; however, the 
static (laboratory) sheen test method must be used during periods 
when observation of a sheen is not possible, such as at night or 
during inclement conditions. Static sheen testing is not required 
for miscellaneous discharges occurring at the sea floor.
    (b) Treatment Chemicals. The concentration of treatment 
chemicals in discharged chemically treated freshwater and seawater 
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, or
    (2) The maximum manufacturer's recommended concentration, or
    (3) 500 mg/l.
    (c) Toxicity. The toxicity of discharged chemically treated 
freshwater and seawater shall be limited as follows: 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 5-
A for seawater discharges and 5-B for freshwater discharges. 
Critical dilution shall be determined using Table 5 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. Compliance with the toxicity limitation 
shall be demonstrated by conducting 48-hour acute toxicity test 
using Mysidopsis bahia (Mysid shrimp) and Menidia beryllina (Inland 
silverside minnow). The test method is published in ``Methods for 
Measuring Acute Toxicity of Effluents to Marine and Freshwater 
Organisms'' (EPA/600/4-90/027F). The results for both species shall 
be reported on the monthly DMR, within two months of the discharge. 
The permittee shall submit a copy of all laboratory reports with the 
DMR.
    (d) Monitoring Requirements for discharged chemically treated 
freshwater and seawater:
    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 also apply to seawater and freshwater discharges which have 
been chemically treated previously described for produced water in 
Part I. B.3
    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.

   Table 5-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"
----------------------------------------------------------------------------------------------------------------
All...................................  0 to 1,000..............        12          24.7        24.5        24.6
                                        >1,000 to 10,000........        11.2        12.4        12.2        14
                                        >10,000.................         9.6        24          23          20
----------------------------------------------------------------------------------------------------------------


  Table 5-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..............         1.1         1.2         2.9         2.9
                                        >1,000 to 10,000........        19          39          28          24
                                        >10,000.................        13          63          41          74
----------------------------------------------------------------------------------------------------------------


[[Page 14996]]

* * * * *

Part II. Standard Conditions for NPDES Permits

Section D. Reporting Requirements

    (13) On page 55753, paragraph 3 is modified to further clarify 
permit transfers, as follows:

3. Transfers

    This permit is not transferable to any person except after 
notice to the Regional Administrator. Any new owner or operator 
shall submit a notice of intent (NOI) to be covered under this 
general permit according to procedures presented at Part I.A.4. 
However, if a permittee notifies EPA prior to the transfer of 
operatorship, no additional NOI documentation need be submitted by 
the new operator. 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.

* * * * *

Part III. Monitoring Reports and Permit Modification

    (14) On page 55754, Section A is corrected to recognize that 
monitoring reports are to be submitted by the facility operator, as 
follows:

Section A. Monitoring Reports

    The operator of each facility shall be responsible for 
submitting monitoring results for each facility within each lease 
block.

    On page 55754, a new paragraph is added to the end of Part III.B.

Part III. Monitoring Reports and Permit Modification

Section B. Permit Modification

    This permit may be modified at any time if, on the basis of any 
new data, other than revised regulations, guidance, or test methods, 
that was not available at the time of permit issuance and would have 
justified the application of different permit conditions at the time 
of issuance. For NPDES general permits, this includes any 
information indicating that cumulative effects on the environment 
are unacceptable. Such cumulative effects on the environment may 
include unreasonable degradation of the marine environment due to 
continued discharges, in which case the Director, Water Division, 
Region 4, may determine that additional conditions are necessary to 
protect the marine environment. Any permit modification will be 
conducted in accordance with 40 CFR Parts 122.62 and 122.63.
* * * * *

Part IV. Test Procedures and Definitions

Section B. Definitions

    On page 55755, a new paragraph 14 is inserted to define 
condensation water, as follows:

    14. Condensation water means water that is produced as a result 
of condensation during the production process that results in a 
direct discharge without the condensate being used for any other 
purpose prior to discharge.

    On page 55756, a new paragraph 26 is inserted to define Eastern 
Portion of the Gulf of Mexico, as follows:

    26. Eastern Portion of the Gulf of Mexico is that area of 
Federal waters in the Gulf of Mexico seaward of the outer boundary 
of the territorial seas of Mississippi, Alabama, and Florida. This 
is EPA, Region 4's jurisdictional division.

    On page 55756, a new paragraph 51 is inserted to define Synthetic 
Based Drilling Fluids (SBFs) as follows:

    51. Synthetic Based Drilling Fluids (SBFs) are drilling fluids 
where the continuous phase is a synthetic material of combination of 
synthetic materials, with water as the dispersed phase.

    The following two paragraphs 55 in Part IV.B. are renumbered as 
follows:

    58. Uncontaminated Freshwater ``freshwater which is discharged 
without the addition of chemicals; examples include: (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 released 
during fire protection tests and training, and (4) water used to 
pressure test piping.''
    59. 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.
* * * * *
    On pages 55755 through 55757, due to the addition of new paragraphs 
14, 26, 51 and the renumbering of the two paragraphs 55 to 58 and 59, 
the remaining paragraphs are renumbered appropriately.

Appendix A

    (15) On page 55761, EPA has deleted appendix A and replaced it 
with two new Tables--Critical Dilution Tables 4 and 4-A, as follows:

  Table 4-A.--Produced Water Critical Dilutions (Percent Effluent) for
                 Water Depths of Greater Than 200 Meters
------------------------------------------------------------------------
                                                    Pipe diameter
                                           -----------------------------
         Discharge rate (bbl/day)            >0'' to   >5'' to   >7'' to
                                               5''       7''       9''
------------------------------------------------------------------------
>0 to 500.................................     0.11      0.11      0.11
501 to 1000...............................     0.22      0.22      0.22
1001 to 2000..............................     0.37      0.37      0.37
2001 to 3000..............................     0.48      0.48      0.48
3001 to 4000..............................     0.56      0.56      0.56
4001 to 5000..............................     0.65      0.66      0.66
5001 to 6000..............................     0.73      0.78      0.78
6001 to 7000..............................     0.77      0.78      0.78
7001 to 8000..............................     0.84      0.86      0.86
------------------------------------------------------------------------


  Table 4-A.--Produced Water Critical Dilutions (Percent Effluent) for
                 Water Depths of Greater Than 200 Meters
------------------------------------------------------------------------
                                                    Pipe diameter
                                           -----------------------------
         Discharge rate (bbl/day)            >0'' to   >5'' to   >7'' to
                                               5''       7''       9''
------------------------------------------------------------------------
>0 to 500.................................     0.08      0.08      0.08
501 to 1000...............................     0.12      0.12      0.12
1001 to 2000..............................     0.18      0.18      0.18
2001 to 3000..............................     0.22      0.22      0.22
3001 to 4000..............................     0.24      0.25      0.25
4001 to 5000..............................     0.28      0.28      0.28
5001 to 6000..............................     0.30      0.30      0.31
6001 to 7000..............................     0.32      0.32      0.32
7001 to 8000..............................     0.35      0.35      0.35
------------------------------------------------------------------------

    (16) On pages 55757-55758, on Table 2 ``Existing Sources-
Effluent Limitations, Prohibitions, and Monitoring Requirements for 
the Eastern Gulf of Mexico NPDES General Permit'' and Table 3 ``New 
Sources-Effluent Limitations, Prohibitions, and Monitoring 
Requirements for the Eastern Gulf of Mexico NPDES General Permit'' 
are retitled to ``Existing Sources'' and `` New Sources.'' A 
correction is made to the Sanitary Flow Measurement reporting 
requirements on both tables to add a ``Recorded/Reported Value'' for 
``Estimated Flow'' and to the units used for the ``Flow'' parameter 
of the Produced Water Measurement as follows:

[[Page 14997]]

Existing Sources

                                        Table 2.--Effluent Limitations, Prohibitions, and Monitoring Requirements
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                            Monitoring requirement
                                      Regulated & monitored   Discharge limitation/ --------------------------------------------------------------------
             Discharge                 discharge parameter         prohibition            Measurement                                Recorded/reported
                                                                                           frequency         Sample  type/method           value
--------------------------------------------------------------------------------------------------------------------------------------------------------
Drilling Fluids....................  Oil-based Drilling      No discharge..........
                                      Fluids.
                                     Oil-contaminated        No discharge..........
                                      Drilling Fluids.
                                     Drilling Fluids to      No discharge..........
                                      Which Diesel Oil has
                                      been Added.
                                     Mercury and Cadmium in  No discharge of         Once per new source    Flame and flameless    mg Hg and mg Cd/kg in
                                      Barite.                 drilling fluids if      of barite used.        AAS.                   stock barite.
                                                              added barite contains
                                                              Hg in excess of 1.0
                                                              mg/kg or Cd in excess
                                                              of 3.0 mg/kg (dry wt).
                                     Toxicity a............  30,000 ppm daily        Once/month...........  Grab/96-hr LC50 using  Minimum LC50 of tests
                                                              minimum.               Once/end of well b...   Mysidopsis bahia;      performed and
                                                             30,000 ppm monthly      Once/month...........   Method at 58 FR        monthly average
                                                              average minimum.                               12507.                 LC50.
                                     Free Oil..............  No free oil...........  Once/day prior to      Static sheen; Method   Number of days sheen
                                                                                      discharge.             at 58 FR 12506.        observed.
                                     Maximum Discharge Rate  1,000 barrels/hr......  Once/hour............  Estimate.............  Max. hourly rate in
                                                                                                                                    bbl/hr.
                                     Mineral Oil...........  Mineral oil may be
                                                              used only as a
                                                              carrier fluid,
                                                              lubricity additive,
                                                              or pill.
                                     Drilling Fluids         Record................  Once/well............  Inventory............  Chemical
                                      Inventory.                                                                                    constituents.
                                     Volume................  Report................  Once/month...........  Estimate.............  Monthly total in bbl/
                                                                                                                                    month.
                                     Within 1000 Meters of    No discharge
                                      an Area of Biological
                                      Concern (ABC).
Drill Cuttings.....................    Note: Drill cuttings are subject to the same limitations/prohibitions as drilling fluids except Maximum Discharge
                                                                                             Rate.
                                     Free Oil..............  No Free oil...........  Once/day prior to      Static sheen; Method   Number of days sheen
                                                                                      discharge.             at 58 FR 12506.        observed.
                                     Volume................  Report................  Once/month...........  Estimate.............  Monthly total in bbl/
                                                                                                                                    month.
Produced Water.....................  Oil and Grease........  42 mg/l daily maximum   Once/month c.........  Grab/Gravimetric.....  Daily max. and
                                                              and 29 mg/l monthly                                                   monthly avg.
                                                              average.
                                     Toxicity..............  Acute toxicity (LC50);  Once/2 months........  Grab/96-hour LC50      Minimum LC50 and LPC
                                                              critical dilution as                           using Mysidopsis       for both species and
                                                              specified by                                   bahia and inland       full laboratory
                                                              requirements at Part                           silverside minnow      report.
                                                              I.B.3(b).                                      (Method in EPA/600/4-
                                                                                                             90/027F).
                                     Flow (MGD)............  ......................  Once/month...........  Estimate.............  Monthly rate.
                                     Within 1000 meters of   No Discharge.
                                      an Area of Biological
                                      Concern (ABC).
Deck Drainage......................  Free Oil..............  No free oil...........  Once/day when          Visual sheen.........  Number of days sheen
                                                                                      discharging d.                                observed.
                                     Volume (bbl/month)....  ......................  Once/month...........  Estimate.............  Monthly total.
Produced Sand......................  No Discharge.
Well Treatment, Completion, and      Free oil..............  No free oil...........  Once/day when          Static sheen.........  Number of days sheen
 Workover Fluids (includes packer                                                     discharging.                                  observed.
 fluids) e.
                                     Oil and Grease........  42 mg/l daily maximum   Once/month...........  Grab/Gravimetric.....  Daily max. and
                                                              and 29 mg/l monthly                                                   monthly avg.
                                                              average.
                                     Priority Pollutants...  No priority pollutants  .....................  Monitor added
                                                                                                             materials.
                                     Volume (bbl/month)....  ......................  Once/month...........  Estimate.............  Monthly total.
Sanitary Waste (Continuously manned  Solids................  No floating solids....  Once/day, in daylight  Observation..........  Number of days solids
 by 10 or more persons) f.           Residential Chlorine..  At least (but as close  Once/month...........  Grab/Hach CN-66-DPD..   observed.
                                                              to 1 mg/l.                                                           Concentration.
                                     Flow (MGD)............  ......................  Once/month...........  Estimate.............  Monthly ave.
Sanitary Waste (Continuously manned  Solids................  No Floating solids....  Once/day, in daylight  Observation..........  Number of days solids
 by 9 or fewer persons or                                                                                                           observed.
 intermittently by any).
Domestic Waste.....................  Solids................  No floating solids; no  Once/day following     Observation..........  Number of days solids
                                                              food waste within 12    morning or midday                             observed.
                                                              miles of land;          meal at time of
                                                              comminuted food waste   maximum expected
                                                              smaller than 25-mm      discharge.
                                                              beyond 12 miles.

[[Page 14998]]

 
Miscellaneous Discharges--           Free Oil                No Free Oil...........  Once/day when          Visual sheen.........  Number of days sheen
 Desalination Unit; Blowout          Treatment Chemicals...  Most Stringent of: EPA   discharging.                                  observed.
 Preventer Fluid; Uncontaminated                              label registration,
 Ballast/Bilge Water; Mud,                                    maximum
 Cuttings, and Cement at the                                  manufacturer's
 Seafloor; Uncontaminated Seawater;                           recommended dose, or
 Boiler Blowdown; Source Water and                            500 mg/l..
 Sand; Uncontaminated Fresh Water;
 Excess Cement Slurry; Diatomaceous
 Earth; Filter Media; Condensation
 water.
Miscellaneous discharges of          Free Oil..............  No Free Oil...........  1/week...............  Visual Sheen.........  Number of days sheen
 seawater and freshwater to which    Toxicity..............  48-hour ave. minimum    Rate Dependent.......  Grab.................   observed.
 treatment chemicals have been                                NOEC and monthly ave.                                                Lowest NOEC observed
 added.                                                       minimum NOEC.                                                         for either of the
                                                                                                                                    two species.
--------------------------------------------------------------------------------------------------------------------------------------------------------
a Toxicity test to be conducted using suspended particulate phase (SPP) of a 9:1 seawater: mud dilution. The sample shall be taken beneath the shale
  shaker, or if there are no returns across the shaker, the sample must be taken from a location that is characteristic of the overall mud system to be
  discharged.
b Sample shall be taken after the final log run is completed and prior to bulk discharge.
c The daily maximum concentration may be based on the average of up to four grab sample results in the 24 hour period.
d When discharging and facility is manned. Monitoring shall be accomplished during times when observation of a visual sheen on the surface of the
  receiving water is possible in the vicinity of the discharge.
e No discharge of priority pollutants except in trace amounts. Information on the specific chemical composition shall be recorded but not reported
  unless requested by EPA.
f Any facility that properly operates and maintains a marine sanitation device (MSD) that complies with pollution control standards and regulations
  under Section 312 of the Act shall be deemed to be in compliance with permit limitations for sanitary waste. The MSD shall be tested yearly for proper
  operation and test results maintained at the facility.

New Sources

                                        Table 3.--Effluent Limitations, Prohibitions, and Monitoring Requirements
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                            Monitoring requirement
                                      Regulated & monitored   Discharge limitation/ --------------------------------------------------------------------
             Discharge                 discharge parameter         prohibition            Measurement                                Recorded/reported
                                                                                           frequency         Sample  type/method           value
--------------------------------------------------------------------------------------------------------------------------------------------------------
Drilling Fluids....................  Oil-based Drilling      No discharge..........
                                      Fluids.                No discharge..........
                                     Oil-contaminated
                                      Drilling Fluids.
                                     Drilling Fluids to      No discharge
                                      Which Diesel Oil has
                                      been Added.
                                     Mercury and Cadmium in  No discharge of         Once per new source    Flame and flameless    mg Hg and mg Cd/kg in
                                      Barite.                 drilling fluids if      of barite used.        AAS.                   stock barite.
                                                              added barite contains
                                                              Hg in excess of 1.0
                                                              mg/kg or Cd in excess
                                                              of 3.0 mg/kg (dry wt).
                                     Toxicity \a\..........  30,000 ppm daily        Once/month Once/end    Grab/96-hr LC50 using  Minimum LC50 of tests
                                                              minimum.                of well \b\.           Mysidopsis bahia;      performed and
                                                             30,000 ppm monthly      Once/month...........   Method at 58 FR        monthly average
                                                              average minimum.                               12507.                 LC50.
                                     Free Oil..............  No free oil...........  Once/day prior to      Static sheen; Method   Number of days sheen
                                                                                      discharge.             at 58 FR 12506.        observed.
                                     Maximum Discharge Rate  1,000 barrels/hr......  Once/hour............  Estimate.............  Max. hourly rate in
                                                                                                                                    bbl/hr.
                                     Mineral Oil...........  Mineral oil may be
                                                              used only as a
                                                              carrier fluid,
                                                              lubricity additive,
                                                              or pill.
                                     Drilling Fluids         Record................  Once/well............  Inventory............  Chemical
                                      Inventory.                                                                                    constituents.
                                     Volume................  Report................  Once/month...........  Estimate.............  Monthly total in bbl/
                                                                                                                                    month.
                                     Within 1000 Meters an   No discharge.
                                      Areas of Biological
                                      Concern (ABC).
Drill Cuttings.....................       (4) Note: Drill cuttings are subject to the same limitations/
                                         prohibitions as drilling fluids except Maximum Discharge Rate.
                                     Free Oil..............  No free oil...........  Once/day prior to      Static sheen; Method   Number of days sheen
                                                                                      discharge.             at 58 FR 12506.        observed.
                                     Volume................  Report................  Once/month...........  Estimate.............  Monthly total in bbl/
                                                                                                                                    month.

[[Page 14999]]

 
Produced Water.....................  Oil and Grease........  42 mg/l daily maximum   Once/month \c\.......  Grab/Gravimetric.....  Daily max. and
                                                              and 29    mg/l                                                        monthly avg.
                                                              monthly average.
                                     Toxicity..............  Acute toxicity (LC50);  Once/2 months........  Grab/96-hour LC50      Minimum LC50 and LPC
                                                              critical dilution as                           using Mysidopsis       for both species and
                                                              specified by the                               bahia and inland       full laboratory
                                                              requirements at Part                           silverside minnow      report.
                                                              I.B.3(b).                                      (Method in EPA/600/4-
                                                                                                             90/027F).
                                     Flow (MGD)............  ......................  Once/month...........  Estimate.............  Monthly rate.
                                     Within 1000 meters of   No discharge.
                                      an Area of Biological
                                      Concern (ABC).
Deck Drainage......................  Free Oil..............  No free oil...........  Once/day when          Visual sheen.........  Number of days sheen
                                                                                      discharging \d\.                              observed.
                                     Volume (bbl/month)....  ......................  Once/month...........  Estimate.............  Monthly total.
Produced Sand......................  No Discharge.
Well Treatment, Completion, and      Free Oil..............  No free oil...........  Once/day when          Static sheen.........  Number of days sheen
 Workover Fluids (includes packer    Oil and Grease........  42 mg/l daily maximum    discharging.          Grab/Gravimetric.....   observed.
 fluids) \c\.                                                 and 29 mg/l monthly    Once/month...........                         Daily max. and
                                                              average.                                                              monthly avg.
                                     Priority Pollutants...  No priority pollutants  .....................  Monitor added
                                                                                                             materials.
                                     Volume (bbl/month)....  ......................  Once/month...........  Estimate.............  Monthly total.
Sanitary Waste (Continuously manned  Solids................  No floating solids....  Once/day, in daylight  Observation..........  Number of days solids
 by 10 or more persons) \f\.         Residential Chlorine..  At least (but as close  Once/month...........  Grab/Hach CN-66-DPD..   observed.
                                                              to 1 mg/l.                                                           Concentration.
                                     Flow (MGD)............  ......................  Once/month...........  Estimate.............  Monthly ave.
Sanitary Waste (Continously manned   Solids................  No floating solids....  Once/day, in daylight  Observation..........  Number of days solids
 by 9 or fewer persons or                                                                                                           observed.
 intermittently by any) \f\.
Domestic Waste.....................  Solids................  No floating solids; no  Once/day following     Observation..........  Number of days solids
                                                              food waste within 12    morning or midday                             observed.
                                                              miles of land;          meal at time of
                                                              commminuted food        maximum expected
                                                              waste smaller than 25-  discharge.
                                                              mm beyond 12 miles.
Miscellaneous Discharges--           Free Oil..............  No free oil...........  Once/day when          Visual sheen.........  Number of days sheen
 Desalination Unit; Blowout          Treatment Chemicals...  Most Stringent of: EPA   discharging.                                  observed.
 Preventer Fluid; Uncontaminated                              label registration,
 Ballast/Bilge Water; Mud,                                    maximum
 Cuttings, and Cement at the                                  manufacturer's
 Seafloor; Uncontaminated Seawater;                           recommended dose, or
 Boiler Blowdown; Source Water and                            500 mg/l.
 Sand; Uncontaminated Freshwater;
 Excess Cement Slurry; Diatomaceous
 Earth Filter Media; Condensation
 water.
Miscellaneous discharges of          Free Oil..............  No Free Oil...........  1/week...............  Visual Sheen.........  Number of days sheen
 seawater and freshwater to which    Toxicity..............  48-hour ave. minimum    Rate Dependent.......  Grab.................   observed.
 treatment chemicals have been                                NOEC and monthly ave.                                                Lowest NOEC observed
 added.                                                       minimum NOEC.                                                         for either of the
                                                                                                                                    two species.
--------------------------------------------------------------------------------------------------------------------------------------------------------
a Toxicity test to be conducted using suspended particulate phase (SPP) of a 9:1 seawater:mud dilution. The sample shall be taken beneath the shale
  shaker, or if there are no returns across the shaker, the sample must be taken from a location that is characteristic of the overall mud system to be
  discharged.
b Sample shall be taken after the final log run is completed and prior to bulk discharge.
c The daily maximum concentration may be based on the average of up to four grab sample results in the 24 hour period.
d When discharging and facility is manned. Monitoring shall be accomplished during times when observation of a visual sheen on the surface of the
  receiving water is possible in the vicinity of the discharge.
e No discharge of priority pollutants except in trace amounts. Information on the specific chemical composition shall be recorded but not reported
  unless requested by EPA.
f Any facility that properly operates and maintains a marine sanitation device (MSD) that complies with pollution control standards and regulations
  under Section 312 of the Act shall be deemed to be in compliance with permit limitations for sanitary waste. The MSD shall be tested yearly for proper
  operation and test results maintained at the facility.

[FR Doc. 01-6175 Filed 3-13-01; 8:45 am]
BILLING CODE 6560-50-P