Revised December 17, 1998

UNITED STATES COURT OF APPEALS

For the Fifth Circuit

___________________________

No. 97-60042

___________________________

TEXAS OIL & GAS ASSOCIATION; MARATHON OIL COMPANY; TRUSTEES FOR

ALASKA; NATURAL RESOURCES DEFENSE COUNCIL; COOK INLET KEEPER;

NATIONAL WILDLIFE FEDERATION; ALASKA CLEAN WATER ALLIANCE;

GREENPEACE; ALASKA CENTER FOR THE ENVIRONMENT; ALASKA MARINE

CONSERVATION COUNCIL; KACHEMAK BAY CONSERVATION SOCIETY; ALASKA

WAVERIDERS; UNION OIL CO. CA; PHILLIPS PETROLEUM; SHELL OIL CO.;

RAILROAD COMMISSION OF TEXAS; STATE OF TEXAS,

Petitioners,

VERSUS

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY,

Respondent.

______________________________________________________

AMERICAN PETROLEUM INSTITUTE,

Petitioner,

VERSUS

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY; CAROL M. BROWNER,

ADMINISTRATOR, UNITED STATES ENVIRONMENTAL PROTECTION AGENCY,

Respondents.

___________________________

No. 97-60321

___________________________

RAILROAD COMMISSION OF TEXAS; STATE OF TEXAS,

Petitioners,

VERSUS2 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY,

Respondent.

______________________________________________________

Petitions for Review of Orders of the

Environmental Protection Agency

______________________________________________________ December 10, 1998

Before REAVLEY, DAVIS, and DUHE’, Circuit Judges.

W. EUGENE DAVIS, Circuit Judge:

Eighteen petitioners from six consolidated actions seek review

and reversal of a series of final effluent limitation guidelines

for the coastal oi l- and gas-producing industry, promulgated on

January 15, 1997 by the U nited States Environmental Protection

Agency ("EPA") pursuant to Sections 301, 304, 306-08, and 501 of

the Clean Water Act ("CWA" or "Act"), 33 U.S.C. §§ 1311, 1314,

1316-18, 1361. Three of the petitioners also seek review of a

general National Pollution Discharge Elimination System permit

issued on January 9, 1995 by EPA Region 6 ("Region 6") pursuant to

Section 402 of the CWA, 33 U.S.C. § 1342. Petitioners challenge the

EPA’s promulgation of zero discharge limits on produced water and

produced sand, the EPA’s de cision to set more lenient discharge

limits for coastal facilities in Cook Inlet, Alaska than for other

coastal facilities, and Region 6's issuance of a g eneral permit

banning the discharge of produced water from coastal facilities in

Texas.

For reaso ns that follow, we uphold the EPA’s zero discharge

limits for produced water and produced sand in the effluent

limitation guidelines and its order setting more lenient discharge1 A "point source" is "any discernible, confined, and discrete

conveyance . . . from which pollutants are or may be discharged."

33 U.S.C. § 1362(14). The CWA requi res the EPA to identify and

categorize all point sources warranti ng effluent guidelines. 33

U.S.C. §§ 1314(m), 1316(b)(1)(A).

3 limits for produced water and drilling wastes in Cook Inlet. This

decision makes it unnecessary for us to reach the challenges to the

general permit.

I.

Congress enacted the CWA in 1972 "to restore and maintain the

chemical, physical, and biolo gical integrity of the Nation’s

waters." 33 U.S.C. § 1251(a). As pa rt of this mission, the Act

declared a national goal that the discharge of pollutants into the

navigable waters be eliminated by 1985. 33 U.S.C. § 1251(a)(1). It

was designed to achieve this goal through a system of effluent

limitations guidelines ("ELGs") and National Pollutant Discharge

Elimination System ("NPDES") permits that set technology-based

discharge limits for all categories and subcategori es of water

po llution point sources. 1 Although the statutory framework of the

CWA has already been detailed at length by both the Supreme Court

and this Court, see EPA v. Nat’l Crushed Stone Ass’n

, 449 U.S. 64,

101 S. Ct. 295 (1980); Am. Petroleum Inst. v. EPA

, 661 F.2d 340

(5th Cir. 1981), a brief review of ELGs a nd NPDES permits is

helpful in understanding the present case.

ELGs are the rulemaking device prescribed by the CWA to set

national effluent limitations for categories and subcategories of

point sources. 33 U.S.C. § 131 4(b). An "effluent limitation" is4

"any rest riction established by a State or the Administrator on

quantities, rates, and concentrations of chemical, physical,

biological, and other constituents which are discharged from point

sources into navigable waters, the waters of the contiguous zone,

or the ocean, including sc hedules of compliance." 33 U.S.C. §

1362(11). These limitations are technology-based rather than harmb ased; that is, they reflect the capabilities of availabl e

p ollution control technologies to prevent or limit different

discharges rather than the impact that those discharges have on the

waters. See generally E.I. du Pont de Nemours & Co. v. Train , 430

U.S. 112, 130-31, 97 S. Ct. 965, 976-77 (1977); Am. Petroleum

Inst.

, 661 F. 2d at 343-44. The CWA prescribes progressively more

stringent technological standards that the EPA must use as a

guidepost in setting discharge limits for regulated pollutants. 33

U.S.C. § 1311(b)(1).

Under this scheme, since March 31, 1989, a majority of ELGs--

including most of those at issue in the present case--have been

required to represent the "best available technology economically

achievable" ("BAT"). 33 U.S.C. §§ 1311(b)(2), 1314(b)(2). In other

words, in promulgating ELGs the EPA must set discharge limits that

reflect the amount of pollutant that would be discharged by a point

source employing the best availab le technology that the EPA

determines to be economically feasible across the category or

subcategory as a whole. BAT is the CWA’s most stringent standard.

"Congress intended these limitations to be based on the performance

of the single best-performing plant in an industrial field." Chem.5

Mfrs. Ass’n v. EPA , 870 F.2d 177, 226 (5th Cir. 1989).

The CWA specifies several factors that must be considered by

the EPA in determining BAT limits:

Factors relating to t he assessment of best available

technology shall take into account the age of equipment and

facilities involved, the process employed, the engineering

aspects of the applicati on of various types of control

techniques, process changes, the cost of achieving such

effluent reduction, non-water quality environmental impact

(including energy requirements), and such other factors as the

Administrator deems appropriate . . . .

33 U.S.C. § 1314(b)(2)(B). The EPA nonetheless h as considerable

discretion in evaluating the relevant factors and determining the

weight to be accorded to each in reaching its ultimate BAT

determination. See Natur al Resources Defense Council v. EPA , 863

F.2d 1420, 1426 (9th Cir. 1988). Thus, the EPA has significant

leeway in d etermining how the BAT standard will be incorporated

into final ELGs.

Despite their central role in the framework of the CWA, ELGs

are not self-executing. They cannot be enforced against individual

dischargers, and individual dischargers are under no legal

obligation to obey the limits set by ELGs. Rather, ELGs achieve

their bite only afte r they have been incorporated into NPDES

permits. See Am. Paper Inst., Inc. v. EPA

, 996 F.2d 346, 350 (D.C.

Cir. 1993) (the "rubber hits the road" only when ELGs are

incorporated into NPDES permits); Am. Petroleum Inst.

, 661 F.2d at

344 (NPDES permits "transform[] generally applicable effluent

limitations

. . . i nto obligations (including a timetable for

compliance) of the individual discharger.") (quoti ng EPA v.2 NPDES permits may be issued either by the EPA or, in those

ju risdictions where the EPA has authorized a state agency to

administer the NPDES program, by a state agency subject to EPA

review. See 33 U.S.C. § 1342(a)-(d).

3 A preexisting NPDES permit is not altered by the creation of

new ELGs. No NPDES permi t, however, may be issued for a term

exceeding five years. 33 U.S.C. § 1342(a)(3), (b)(1)(A). This

ensures that all newly reissued permits will incorporate the most

recent ELGs.

6 California Ex Rel. State Water Resources Control Bd.

, 426 U.S. 200,

205, 96 S. Ct. 2022, 2025 (1976)).

NPDES permits are the CWA’s implementation mechanism; they are

the instrument by which ELGs are made binding on individual

dischargers. The CWA makes it unlawful to discharge any pollutant

from any point source without an NPDES permit. 2 33 U.S.C. §

1311(a); A m. Petroleum Inst. v. EPA

, 787 F.2d 965, 969 (5th Cir.

1986). These permits must generally incorporate, as a technologybased floor, all applicable ELGs promulgated by the EPA for the

pertinent point source category or subcategory. 33 U.S.C. §

1342(a)(1). There are only two ways for an individual discharger to

avoid the inc orporation of applicable ELGs into an NPDES permit:

first, where the discharger is operating under a permit that was

is s ued prior to the promulgation of the ELGs 3 ; or second, in rare

cases, where the EPA grants the discharger a variance based on the

discharger’s demonstration that it is "fundamentally different"

from other dischargers in the category or subcategory. 33 U.S.C. §

1311(n); 40 C.F.R. §§ 122.21(m)(1), 125.30-125.32.

In situations where the EPA has not yet promulgated any ELGs

for the point source category or subcategory, NPDES permits must7

i ncorporate "such conditions as the Administrator determines ar e

n ecessary to carry out the provisions of the Act." 33 U.S.C. §

1342(a)(1). See also Am. Petroleum Inst.

, 787 F.2d at 969. In

practice, this means that the EPA must determine on a case-by-case

basis what effluent limitations represent the BAT level, using its

"best professional judgment." 40 C.F.R. § 125.3(c)-(d). Individual

judgments thus take the place of uniform national guidelines, but

the technology-based standard remains the same.

NPDES permit s may be either individual or general; that is,

either site-specific or generally applicable to a whole category or

subcategory of point sources. General NPDES permits are permissible

only where th e point sources: 1) all involve the same or similar

types of operations; 2) discharge the same types of wastes; and 3)

require the same or similar monitoring. 40 C.F.R. § 122.28. The EPA

frequently uses such general permits for the oil and gas industry.

We turn now to the specific issues raised in this appeal.

II.

The consolidated petitions challenge various actions taken by

the EPA in fulfilling its statutory mandate under the CWA with

respect to the Coastal Subcategory of the Oil and Gas Extraction

Point Source Category. The Coastal Subcategory consists of oil and

gas exploration, drilling, production, and well treatment

facilities located in or on a water of the United States--including

wetlands--landward of the inner boundary of the territorial seas.

Except for facilities in Cook Inlet, Alaska, most coastal oil and

gas facilities are located on wetlands or relatively shallow bodies8

of water. The Cook Inlet coastal facilities consist of platforms in

relatively deep water, similar to offshore oil and gas facilities.

The Coastal Subcategory generates a number of pollutant waste

streams, including produced water, produced sand, and drilling

wastes. Produced water is highly saline water brought up from wells

along with oil and gas during the production phase. Among the toxic

pollutants found in it are phenol, benzene, naphthalene,

ethylbenzene, and toluene. Produced san d consists of slurried

particles that surface from hydraulic fracturing and accumulated

formation sands and other particles generated during production. It

may also include sludges generated in produced water treatment

systems. Prod uced sand contains toxic metals and essentially the

same toxic organic po llutants found in produced water. Drilling

wastes consist of drilling fluids and drill cuttings generated

during exploration and well development operations. They contain a

number of toxic pollutants, including organics and metals.

Petitioners challenge two separate EPA regulatory actions

affecting members of the Coastal Subcategory. First, they challenge

as arbitrary and capricious a General Permit issued by Region 6

regulating discharge of produced water for coastal oil and gas

facilities in Texas and Louisiana. Second, they challenge as

arbitrary, capricious, and unlawful the final ELGs promulgated by

the EPA regulating discharge of produced water, produced sand, and

drilling wastes for the entire Coastal Subcategory. The pertinent

history of each action is laid out below.

A.9

The challenged General Permit was issued in 1995 by Region 6,

acting without the guidance of any ELGs a nd therefore exercising

its best professional judgment. In December 1992, Region 6 proposed

to issue a General Permit governing the discharge of produced water

and produced sand for coastal oil and gas facilities in Texas and

Louisiana. The pe rmit proposal was preceded by an examination of

the various types of produced water and produced sand c ontrol

technologies available to coastal operators in Texas and Louisiana.

From this examination, Region 6 determined in its best professional

judgment that the BAT standard required the use of reinjection

technology, which produces no discharge. Region 6 therefore

concluded that a zero discharge requirement on produced water and

produced sand best represented the BAT standard, and included such

a limit in the proposed General Permit.

Region 6 received extensive comments on the proposed General

Permit from industry representatives, environmental groups, and the

Railroad Commission of Texas ("RRC"). Following a reevaluation of

its analyses based on these comments, Region 6 determined that a

zero discharge requirement remained economically achievable for

coastal oil and gas facilities in Texas and Louisiana overall, even

though some smaller operators might experience economic failure.

Region 6 also determined that a zero discharge requirement was

necessary to prevent violations of state water quality criteria for

toxicity and salinity.

On January 9, 1995, Region 6 issued a final General Permit

prohibiting the discharge of produced water and produced sand from4 The general permits did not address discharge of drilling

wastes.

10 all existing and future coastal oil and gas facilities in Texas and

Louisiana. 4 The effective date of the General Permit was February

8, 1995. Region 6 also issued an Administrative Order at the same

time allowing coastal operators two years--until January 1, 1997--

to come into compliance with the General Permit.

The final General Permit contained a provision that was absent

in the General Permit as originally proposed. Section B of the

final General Per mit provided that dischargers could apply for

i ndividual permits exempting them from the requirements of th e

General Permit and imposing more lenient discharge limitations.

There is evidence that this provisi on was added at the urging of

the RRC and Texas operators to mitigate the economic consequences

of the General Permit with respect to those facilities in Texas

that would be forced to shut down as a result of the General

Permit’s zero discharge limit. There is also evidence that the

General Permit was not challenged within the 120-day statutory time

limit, 33 U.S.C. § 1369(b)(1)(F), only because Region 6 had

informed the RRC and Texas operators that it would not grant any

individual permits if the General Permit were challenged. Eightytwo operators have applied fo r individual permits, but none have

been granted.

B.

The challenged ELGs r epresent the culmination of nearly two

decad es of rulemaking efforts by the EPA. In 1979, the EPA first11

published ELGs governing waste streams discharged by the Coastal

Subcategory. 44 Fed. Reg. 22,069 (Apr. 13, 1979), codified at 40

C.F.R. Part 435, Subpart D. These ELGs, however, were based on the

CWA’s then-governing technological standard of "best practicable

control technology currently available" ("B PT"). 33 U.S.C. §

1311(b)(1). BPT is the CWA’s least stringent standard. The 1979

ELGs became out dated in 1989, when the CWA-mandated standard

shifted from BPT to BAT. See 33 U.S.C. § 1311(b)(2).

The EPA first took action to establis h BAT-based limits in

1989, when it published a notice of information and request for

comments on the Coastal Subcategory . This notice was followed by

voluminous comments from industry representatives, environmental

groups, and government agencies like the RRC. In 1992, the EPA

distributed a 99-page questionnaire ( "Section 308 Survey" or

"Survey") to all known coastal operators pursuant to its authority

under Section 308 of the CWA, which authorizes the EPA to collect

information necessary to carry out the objectives of the CWA. 33

U.S.C. § 1318. Other information-gathering activities performed by

the EPA included collecting samples and gathering technical data at

three drillin g operations in coastal Louisiana; visiting ten

coastal oil and gas production facilities in Texas and Louisiana to

collect samples of produced water and associated wastes and to

collect technical and cost data; and reviewing state permit data

for all known Texas and Louisiana operators to obtain detailed

information on produced water discharges.

In February 1995, shortly after Region 6 iss ued the General12

Permit, the EPA published its proposed ELGs for the Coastal

Subcategory. 60 Fed. Reg. 9,428 (Feb. 17, 1995). This resulted in

another round of comments and public me etings, followed by

publication of the final ELGs for the Coastal Subcategory on

December 16, 1996. 61 Fed. Reg. 66,085 (Dec. 16, 1996), to be

codified at 40 C.F.R. Part 435. The final ELGs set a zero discharge

limit on produced water and drilling wastes for all coastal oil and

gas facilities except those located in Cook Inlet, Alaska. The

final ELGs also set a zero discharge limit on produced sand for all

coastal oil and ga s facilities, including those located in Cook

Inlet.

The discharge limit on produced water was based on a number of

EPA findings. First, the EPA found that--due to a combination of

factors including operational preference, waterflooding, and state

or federal requirements--no coastal facilities in California,

Florida, Mississippi, Alabama, or the North Slope of Alaska were

discharging produced water. The EPA further found that 99.9 percent

of coastal facilities in Louisiana and Texas ei ther had already

stopped discharging produced water or soon would as a result of new

Louisiana water quality regulations and Region 6’s General Permit,

both of which were set to take full effect in January 1997. The EPA

also noted that 62 percent of coastal facilities along the Gulf of

Mexico had been practicing zero discharge since at least 1994. Of

876 facilities in the Coastal Subcategory, the EPA concluded that

only fourteen would be able to discharge produc ed water lawfully

after January 1997. All but six of those facilities were located in13

Cook Inlet.

The EPA next considered the control technologies available to

coastal dischargers, and concluded that the BAT standards required

all dischargers outside of Cook Inlet to reinject produced water.

T he EPA noted that reinjection was already widely practiced

throughout the Coastal Subcategory, with the exceptio n of Cook

Inlet. Because reinjection results in a zero discharge level, the

EPA determined the proper discharge limit on produced water to be

zero.

Lastly, assessing the eco n omic achievability of the zero

discharge standard, the EPA found that only the six coastal

facilities not already covered by either the General Permit or the

new Louisiana water quality standards would incur a dditional

compliance costs as a result of t he limit, and none of the six

facilities would be forced to close. Moreover, the EPA found the

total economic costs considered i n the context of the coastal

subcategory as a whole to be minimal.

The EPA also conducted an "alternative baseline" analysis in

which it assumed that the General Permit’s zero discharge standard

would not apply to the eighty-two Texas dischargers seeking

individual permits, and that Louisiana’s new water quality

standards would not app ly to eighty-two Louisiana open bay

dischargers. It estimated that 80 percent of coastal facilities in

Texas and Louisiana would still be meeting or be required to meet

zero discharge by January 1997, meaning that those 80 percent would

still incur no additional compliance costs. Assuming that the ELGs14

would cause incremental compliance costs to all eighty-two Texas

individual permit applicants and all eighty-two Louisiana open bay

dischargers, the EPA concluded t hat up to ninety-four wells--or

approximately 2 percent of all Gulf of Mexico coastal wells--could

be first year shut-ins under the zero discharge standard, and that

a maximum of one firm among Louisiana open bay dischargers and

three firms among the Texas individual permit applicants could fail

as a result of the standard. Because this potential failure rate

represented less than 1 percent of all Gulf of Mexico coastal

facilities, the EPA determined that zero discharge remained

economically achievable f or the Coastal Subcategory as a whole

(except Cook Inlet) despite its potentially significant economic

effect on some individual operators.

The EPA pro vided pollution reduction estimates for both the

current requirements analysis and the alternative baseline

analysis. Under the current requirements analysis, the EPA

estimated that the zero discharge limit would reduce discharges of

conventional pollutants by 2,780, 000 pounds per year, of

nonconventional pollutants by 1,490,000,000 pounds per year, and of

toxic pollutants by 228,000 pounds per year. Under the alternative

baselin e analysis, the EPA projected a reduction of conventional

pollutants by 11,300,000 pounds per year, of nonconventional

pollutants by 4,590,000,000 pounds per year, and of toxic

pollutants by 880,000 pounds per year.

The discharge limit on produced sand was based on the EPA’s

finding that only one operator in the country was discha rging15

produced sand, and that even the one discharging operator had

reported plans to cease doing so. Examining available control

technologies, the EPA concluded that the BAT standard required some

combination of landfarming, underground injection, landfilling, and

on-site s torage. Because none of these techniques involved the

discharge of produced sand, the EPA determined the ap propriate

discharge limit for produced sand to be zero. Likewise, because the

zero discharge limit reflected current industry practice, the EPA

found the econo mic effect of the zero discharge limit also to be

zero.

The discharge limit on drilling wastes was based on the EPA’s

finding that, outside of Cook Inlet, the entire Coastal Subcategory

had already attained zero discharge of drilling wastes. Examining

a vailable control technologies, the EPA determined that the BAT

standard required coastal facilities outside of Cook Inlet either

to grind and inject drilling wastes or to dispose of drilling

wastes onshore. Because neither method re sults in any drilling

waste discharge, the EPA found the appropriate discharge limit on

drilling wastes to be zero. The EPA estimated that operators would

incur no cost s under this limit because it reflected current

practices.

In distinguishing Cook Inlet facilities from other coastal

facilities, the EPA found that Cook Inlet facilities face

substantially different circumstances from those face d by other

coa stal facilities. The Cook Inlet facilities are located in

relatively deep water, and operate more like offshore oil and gas5 For exam ple, the EPA estimated that compliance with a zero

discharge limit on drilling wastes would cost Cook Inlet operators

a n additional $8,200,000 annually, as compared to the zer o cost

increase for all other dischargers.

6 Specifically, the EPA determined that "improved gas

flotation" satisfied the BAT s tandard for produced water in Cook

Inlet. Using this determination as a base line, the ELGs limit

produced water oil and g rease concentrations from Cook Inlet

facilities to 42 mg/l on any given day, and 29 mg/l for each

monthly average. Discharge of most drilling wastes is likewise

allowed so long as toxicity limits do not exceed 30,000 ppm.

16 facilities than like other coastal oil and gas facilities. There is

a scarcity of land disposal facilities in the vicinity of Cook

Inlet, and, more significantly, geologic formations in the area are

generally uns uitable for reinjection. There are also unique

difficulties associated with transporting drilling wastes to shore

for disposal. Based on these findings, the EPA determined that the

zero discharge standard for produced water and drilling wastes was

not economically achievable for Cook Inlet facilities because it

would have disproportionate adverse ec onomic impacts. 5 The ELGs

therefore treated Cook Inlet facilities dif ferently from other

coastal facilities, setting more liberal discharge limits. 6 The EPA

never formally designated Cook Inlet facilities as a separate

subcategory of point sources under the CWA.

C.

The final ELGs took effect on January 15, 1997, at which time

they were deemed issued for purposes of judic ial review.

Petitioners Texas Oil and Gas Association ("TOGA"), RRC, and State

of Texas (collectively, "Texas Petitioners") filed two petitions

seeking reversal or remand of the zero discharge limit on produced17

water contained in both the General Permit and the ELGs.

P etitioners American Petroleum Institute, Union Oil Company of

California, Marathon Oil Company, Phillips Petroleum, and Shell Oil

Company (collectively, "Cook Inlet Petitioners") filed three

petitions seeking reversal or remand of the zero discharge limit on

produced sand contained in the ELGs. Petitioners Trustees for

Alaska, Natural Resources Defense Council, Cook Inlet K e eper,

National Wildlife Federation, Alaska Clean Water Alliance,

Greenpeace, Alaska Center for the Environment, Alaska Marine

Conservation Council, Kachemak Bay Conservation Society, and Alaska

Waveriders (collectively, "Alaska Petitioners") filed one petition

seeking reversal or remand of the ELGs to the extent that they

treated Cook Inlet coastal facilities differently f rom other

coastal facilities. The six petit ions were consolidated into the

present action.

The EPA filed a motion to dismiss Texas Petitioners’

challenges to the General Permit for lack of subject matter

jurisdiction, arguing t hat both petitions were filed after the

expiration of the 120-day s tatutory period for seeking judicial

review of the permit. The EPA does not question the timeliness of

any of the challenges to the ELGs. We therefore evaluate the

validity of the ELGs first.

III.

Texas Petitioners argue that the EPA’s decision to set a zero

discharge limit on produced water was based on a flawed analysis of

the economic achievability of the limit. First, they argue that the7 Texas Petitioners also challenge the EPA’s promulgation of a

zero discharge limit on produced water in its new source

performance standards ("NSPS"). It appears from Petitioner TOGA’s

Reply Brief that this challenge rests on the same grounds as the

challenge to the ELGs. See TOGA Reply Brief at 13 ("TMOGA’s point

is that, because EPA’s analysis in setting BAT was flawed, EPA’s

setting of NSPS on the basis of BAT is also flawed."). To the

extent that any independent challenges to the NSPS limits were

made, we hold that they were waived by Texas Petitioners’ failure

to raise the objections during the notice and comment period. See

United States v. L.A. Tucker Truck Lines, Inc.

, 344 U.S. 33, 35-37,

73 S. Ct. 67, 68-69 (1952). Likewise, arguments raised by amicus

parties challenging the accuracy of the EPA’s s hut-in estimates

were not raised to the EPA during notice and comment, and therefore

will not be considered here. Id

.

18 EPA excluded from its consideration wells drilled before 1980 and

not recompleted since then ("pre-1980 wells"), thereby failing to

consider the "age of equipment and facilities" factor mandated by

Section 304(b)(2)(B) of the CWA. 33 U.S.C. § 1314(b)(2)(B). Second,

they argue that the EPA based its pollutant reduction estimates on

a deficient study that egregiously overestimated the pollutant

loading for pro duced water in the Gulf Coast. 7 For reasons that

follow, we are satisfied that the EPA adequately considered the age

factor in promulgating the zero discharge limit, and that the EPA’s

use of the challenged study provides no basis to contest the

produced water limit.

A.

Texas Petitioners challenge substantive conclusions that the

EPA drew from the administrative record. Review of their petitions

is therefore governed by the Administrative Procedure Act ("APA"),

5 U.S.C. §§ 551-59, 701-06, which establishes a deferential

standard of revie w for agency action. To invalidate an agency8 Petitioner TOGA argues that the EPA is no t entitled to APA

deference in th is case because it "failed to consider clearly

specified st atutory factors in its analysis," "failed to rely on

valid reasoning," "failed to explain its radical change in policy,"

and "adopted an inflexible regulation." TOGA instead proposes a "no

deference" standard, and cites several cases that purportedly favor

such a standard. See Chem. Mfrs. Ass’n v. Natural Resources Defense

Council

, 470 U.S. 116, 125, 105 S. Ct. 1102,1107 (1984) (citing

Chevron U. S.A., Inc. v. Natural Resources Defense Council, Inc.

, 467 U.S. 837, 842-43 (1984), 104 S. Ct. 2778, 2781-82; Motor

Vehicle Mfrs. Ass’n v. State Farm Mut. Auto Ins. Co.

, 463 U.S. 29,

42, 103 S. Ct. 2856, 2866 (1983). None of these cases provide any

support for TOGA’s argument. Indeed, M otor Vehicle Mfrs. Ass’n

expressly adopted the "arbitrary and capricious" standard employed

here. Adopting TOGA’s line of reasoning would turn jurisprudence on

its head by requiring us to determine the merits of the case prior

to the standard of review, an impossibly circular task. We decline

TOGA’s invitation to do so.

19 action, the Court must determine that it was "arbitrary,

capricious, an abuse of discretion, or otherwise not in accordance

with law"; "in excess of statutory jurisdicti on, authority, or

limitations, or short of statutory right"; or "without observance

of procedure required by law." 5 U.S.C. § 706(2)(A),(C)-(D). 8

An agency rule is arbitrary and capricious "if the agency has

relied on factors which Congress has not intended it to consider,

entirely failed to consider an important aspect of the problem,

offered an explanation for its decision that runs counter to the

evidence before the agency, or is so implausible that it could not

be ascribed to a di fference in view or the product of agency

expertise." Motor Vehicle Mfrs. Ass’n v. State Farm Mut. Auto. Ins.

Co.

, 463 U.S. 29, 43, 103 S. Ct. 2856, 2867 (1983). The Court must

make a "searching and careful review" to determine whether an

agency action was arbitrary and capricious, but "the ultimate

standard of review is a narrow one." Citizens to Preserve Overton20

Park, Inc. v. Volpe

, 401 U.S. 402, 416, 91 S. Ct. 814, 823 (1971).

Under this deferential standard, the Court may not substitute

its own judgment for that of the agency. Id. at 416, 91 S. Ct. at

823 (1971). Rather, the Court must determine whether the agency

action "bears a rational relationship t o the statutory purposes"

and whether "there is substantial evidence in the record to support

it." Mercy Hosp . of Laredo v. Heckler , 777 F.2d 1028, 1031 (5th

Cir. 1985). If the agency’s reasons and policy choices conform to

minimal standards of rationality, then its actions are reasonable

and must be upheld. Small Refiner Lead Phase-Down Task Force v.

EPA , 705 F.2d 506, 521 (D.C. Cir. 1983); C hem. Mfrs. Ass’n

, 8 7 0

F.2d at 199.

In assessing the validity of the Coastal Subcategory ELGs, the

EPA’s decision "is entitled to a presumption of regularity." Chem.

Mfrs. Ass’n

, 870 F.2d at 198. Thi s presumption places a

"considerable burden" on the challenger to overcome the EPA’s

chosen course of action. Am. Petroleum Inst.

, 787 F.2d at 983. This

is particularly true where--as here--the agency’s decision rests on

an evaluation of complex sc ientific data within the agency’s

technical expertise. See New York v. Reilly

, 969 F.2d 1147, 1152

(D.C. Cir. 1992 ) (stating that courts must be "extremely

deferential" in such cases); Avoyelles Sportsmen’s League, Inc. v.

Marsh , 715 F.2d 897, 910-11 (5th Cir. 1983).

Texas Pet itioners face an especially difficult challenge in

this case, given the proportion of dischargers already practicing

zero discharge at the tim e of rulemaking. The EPA found that 10021

percent of coastal oil and gas facilities outside of Cook Inlet,

Louisiana, and Texas, and at least 62 percent of facilities in

Louisiana and Texas, were practicing zero discharge by 1992. This

finding--not challenged by any party--lends significant additional

weight to the EPA’s "presumption of regularity," suggesting as it

does that reinjection was not only economically achievable but was

actually practiced by a large majority of coastal facilities at the

time of the rulemaking.

Added to this is the EPA’s further finding that only six

coastal facilities would be able to discharge produced water after

January 1997, meaning that the incremental economic impact of the

zero discharge limit on coastal facilities would be limited to only

those six facilities. Even under the alternative baseline analysis,

the EPA still found that 80 percent of coastal facilities in Texas

and Louisiana would be required to practice zero discharge by

January 1997, meaning that only 20 percent of coastal facilities

could suffer any incremental economic impact. These fin dings

present a very signifi cant barrier for Texas Petitioners to

overcome in order to establish that the zero discharge limit is not

economically achievable.

B.

Texas Petitioners first seek to meet their burden by arguing

that the EPA failed to cons ider a statutory factor in making its

BAT determination for produced water. Although the EPA has

significant discretion in deciding how much weight to accord each

statutory factor under the CWA, see Natural Resources Defense22

Council

, 863 F.2d at 1426; Weyerhaeuser Co. v. Costle

, 590 F.2d

1011, 1045 (D.C. Cir. 1978) (Congress left the EPA "discretion to

decide how to account for the [BAT] factors, and how much weight to

give each factor."), it is not free to ignore any individual factor

entirely. Both the CWA, 33 U.S.C. § 1314(b)(2), and the EPA’s own

regulations, 40 C.F.R. § 125.3(c)-(d), state that the EPA s hall

take into account (or apply) certain factors in making a BAT

determination, including "the age of equipmen t and facilities

involved." 33 U.S.C. § 1314(b)(2)(B); 40 C.F.R. § 125.3(d)(3)(I).

Failure to consider the age factor is therefore, under the plain

meaning of the Act and its implementing regulations, an abuse of

discretion. See generally Am. Iron & Steel Inst. v. EPA , 526 F.2d

1027, 1048 (3d Cir. 1975), cert. denied

, 435 U.S. 914 (1978)

(remanding agency rule to EPA where EPA failed to consider a

similar statutory age factor as it bore on the cost or feasibility

of retrofitting certain older steel mills).

Texas Petitioners argue that, although the EPA paid "lip

service" to the age factor, in reality the agency made its

d ecisions without regard to the economic effects of a zero

discharge standard on older wells. They argue that the EPA’s error

resulted from its exclusion of pre-1980 wells from the Section 308

Survey, on which the EPA relied heavily in making its economic

impact analysis. Rather than actually surveying pre-1980 wells, the

EPA extrapolated from information it received on other wells to

estimate the results it would have obtained if it had included pre1980 wells in the Survey. Texas Petitioners characterize this23

omission as "particularly egregious" because the volume of produced

water generated by a well increases as the well ages, meaning that

the expense of meeting a zero di scharge limit rises as the well

g ets older. Thus, they say, the EPA’s economic impact assessm ent

methodology specifically excluded those wells that stood to suffer

the greatest economic impact.

Although the exclusion of pre-1980 facilities may have had

some effect on the precision of the EPA ’s analysis of the age

factor, we cannot agree with Texas Petitioners that this exclusion

rose to the level of an arbitrary and capricious agency action. An

agency’s choice to proceed on the basis of "imperfect" information

is not arbitrary and capricious unless "there is simply no rational

relationship" between the means used to a ccount for any

imperfections and the situation to which those means are applied.

Am. Iron & Steel Inst. v. EPA

, 115 F.3d 979, 1004 (D.C. Cir. 1997)

(citation omitted). Here, the EPA found that the only relevant

distinction between pre-1980 wells and post-1980 wells is that pre1980 wells are primarily "marginal produc ers," producing ten

barrels or less of oil per day. Noting that post-1980 marginal

producers were well-represented in the Section 308 Survey, and that

pre-1980 marginal producers do not differ significantly from post1980 marginal producers, the EPA extrapolated from the Section 308

Survey data to estimate the impact of the zero discharge limit on

pre-1980 facilities. It then confirmed its findings through a

facility-level analysis of economic impacts on the Texas individual

permit applicants. These actions were more than sufficient to24

establish a rational relationship between the Section 308 Survey

data and the pre-1980 wells. Thus, the EPA’s decision to proceed

without collecting data on pre-1 980 wells was not arbitrary and

capricious.

C.

Next, Tex as Petitioners attempt to satisfy their burden by

attacking one of the studies cited by the EPA in promulgating the

produced water limit. A regulation cannot stand if it is based on

a flawed, inaccurate, or misapplied study. "When an agency adopts

a regulation based on a study [th at is] not designed for the

purpose and is limited or criticized by its authors on points

essential to the use sought to be made of it the administrative

action is arbitrary and capricious and a clear error in judgment.

Humana of Aurora, Inc. v. Heckler

, 753 F.2d 1579, 1583 (10th Cir.),

cert. denied , 474 U.S. 863 (1985).

Texas Petitioners argue that the EPA inaccurately derived its

pollutant reduction estimates f rom a limited study ("10-Facility

Study" or "Study") of ten unrepresentative coastal facilities in or

near Louisiana, and then based the zero discharge limit on its

results. The 10-Facility Study reports the results of an EPA

sampling program in which an EPA consultant visited ten facilities

for one day e ach to collect a limited number of samples from a

broad array of processes and waste streams. Texas Petitio ners’

objections to the 10-Facility Study are as follows: 1) Only one of

the facilities involved in the St udy discharged produced water,

while nine used reinjection technology; 2) Only four of the25

facilities studied were in Texas, and all of those were close to

the Louisiana border; 3) In response to comments that the 10-

Facility Study was unrepresentative, the EPA merely removed three

facilities f rom the study, conceding that those facilities were

unrepresentative based on excessive oil and grease concentrations

but maintaining that the remaining seven faciliti es were

representative; 4) Even though the revised Study never concluded

that its results were representative of Gulf Coast discharges, the

EP A used the data from the Study to represent pollutant

concentrations for the entire Gulf of Mexico; and 5) The EPA

ignored the results of a superior study (the "Avanti Study") that

evaluated actual Texas Gulf Coast data from 173 outfalls.

We need not address Texas Petitioners’ individual criticisms

of the 10-Facility Study to resolve this issue, because even if

every one of the criticisms were accurate we still could not

reverse or remand the produced water limit on that basis. The EPA

only used the 10-Facility Study to estimate pollution reduction

benefits that would result from the zero discharge limit. Whatever

value such benefit estimates may have, they are not a required part

of the BAT determination. In applying the BAT standard, the EPA is

not obl igated to evaluate the reasonableness of the relationship

between costs and benefits. S ee EPA v. National Crushed Sto n e

Ass’n , 449 U.S. at 71, 101 S. Ct. at 300 ("in assessing BAT total

cost is [not] to be considered in comparison to effluent reduction

benefits"). Indeed, the EPA may prescribe ELGs whose costs are

significantly disproportionate to their benefits, just as long as9 Texas Petitioners urge us to r everse years of precedent and

to hold that the clear language of the CWA (specifically, 33 U.S.C.

§ 1314(b)(2 )(B)) requires the EPA to perform a cost-benefit

analysis in determining BAT. We find nothing in the language or

history of the CWA that compels such a result.

26 the BAT determination remains economically feasib le for the

industry as a whole. See Am. Petroleum Inst. v. EPA

, 858 F.2d 261,

265 (5th Cir. 1988) ("[A] direct cost/benefit correlation is not

required [fo r BAT], so even minimal environmental impact can be

regulated, so long as the prescribed alternative is

‘technologically and economically achievable.’"). 9 The EPA included

the Study’s effluent reduction estimates only to satisfy the CWA’s

unrelated requirement that the EPA "i dentify" in its regulations

the degree of effluent reduction attainable through the application

of BAT. 33 U.S.C. § 1314(b)(2)(A). They had nothing to do with

either the BAT determination or the actual inclusion of a zero

discharge limit on produced water in the ELGs. As such, even

serious flaws in the effluent reduction estimates could not provide

grounds for remanding the zero discharge limit.

Texas Petitioners attempt to tie the effluent reduction

estimates to the BAT determination by arguing that th e estimates

are integral to the statutory BAT factor of "cost of achieving such

effluent reduction," 33 U.S.C. § 1314(b)(2)(B). They assert that

the cost factor cannot be considered without r eference to the

amount of effluent reduction, and that the EPA cannot properly

consider the cost of achieving a particular effluent reduction if

the degree and quality of the effluent reduction itself is grossly27

mischaracterized. W e disagree. The benefit to be achieved from

adopting a particular pol lution control technology is not an

element of that technology’s cost. The cost of complying with a

BAT-based regulation can be gauged by reference to the cost of the

technology itself, even if the benefits of using that technology

are unclear. Rein jection technolgoy, for example, costs the same

regardless of whether it reduces pollutant discharge by three

million pounds per year or three pounds per year. Thus, the EPA was

fully capable of assessing the "cost o f achieving such effluent

reduction" even if its reduction estimates were flawed.

IV.

Cook Inlet Petitioners argue that, in setting a zero discharge

limit on produced sand in the ELGs, the EPA erroneously refused to

consider a "no free oil" alternative limit based on sand washing

technology. They claim that the EPA, relying exclusively on

prevalent industry practice, closed its mind to any option that did

not involve zero discharge, and thereby ignored a potentially

superior option. We are satisfied that the EPA’s decision to set a

zero discharge limit on produced sand based on nearly uniform

industry practice at the time of rulemaking was valid, and that the

EPA gave adequate attention to the "no free oil" alternative.

A.

Cook Inlet Petitioners, like Texas Petitioners, challenge

substantive conclusions that the EPA drew from the administrative

record. Review of their petitions is therefore governed by the

APA’s deferential "arbitrary and capricious" standard. 5 U.S.C. §28

706(2)(A). If, following a "searching and careful review," Overton

Park

, 401 U.S. at 416, 91 S. Ct. at 823, we find that the agency’s

reasons and policy choices conform to m inimal standards of

r ationality, then its actions are reasonable and must be uphe ld,

Small Refiner

, 705 F.2d at 521. The produced sand limit is entitled

to the sam e "presumption of regularity" as the produced water

limit, Chem. Mfrs. Ass’n

, 870 F.2d at 198, and petitioners carry

the same "considerable burden" to ove rcome this presumption. A m.

Petroleum Inst. , 787 F.2d at 983.

B.

Cook Inlet Petitioners contend that the EPA’s selection of a

zero discharge limit based on the widespread industry use of zero

discharge technologies such as landfarming, underground injection,

landfilling, and onsite storage was arbitrary and capricious. They

argue that the EPA ignored the BAT factors of non-water quality

environmental impacts and cost of achieving effluent reduction, and

that had the EPA taken these factors into account it might have

found that a "no free oil" limit based on sand washing technology

better represented the BAT standard, despite t he fact that it

involves some discharge. Petitioners further suggest that the EPA

gave inadequate consideration to new information showing that sand

washing provides a viable alternative to zero dis charge, meeting

the requirements of the CWA while providing economic and non-water

quality benefits.

These arguments are unpersuasive. Even if the EPA completely

ignored sand washing as an alternative to zero discharge29

technologies, it still did not abuse its discretion. The EPA found-

-and no party disputes--that every coastal facility surveyed except

one was practicing zero discharge at the time of rulemaking, and

that even the one discharging facility was planning to switch to

zero discharge. Given the near-perfect uniformity of industry

practice i n this area, it could hardly be said that the EPA’s

decision to set a zero discharge limit on produced sand did not at

least conform to minimal standards of rationality.

Moreover, the record plainly shows that the EPA gave adequate

consideration to the sand washing option. The EPA thoroughly

explained why it rejected the "no free oil" limit, noting that such

a limit would have been less stringent than the technology-based

limitations in existing NPDES permits in Texas, Lou isiana, and

Arkansas, and that even when the limit is met, produced sand still

contains "total suspend ed solids" and may still contain oil,

grease, and other pollutants. The EPA did not ignore the sand

washing option; it simply found that sand washing was not always

effective in eliminating residual pollutants from produced sand.

Accordingly, the EPA determined that sand washing did not meet the

BAT standard. We can find no fault with this determination.

V.

Alaska Petitioners argue that the EPA violated the CWA when

the agency opted to set different effluent limits for Cook Inlet

without labeling Cook Inlet as a separate subcategory. They claim

that the CWA requires the EPA to establish nationally uniform ELGs

for each category or subcategory of point sources, and that30

differentiated trea tment of point sources within a category or

subcategory v iolates the express terms of the statute. We are

satisfied t hat the EPA’s actions were based on a permissible

construction of the CWA, and therefore must be upheld.

A.

Challenges to an agency interpretation of a statute that the

agency administers are governed by the two-step standard of review

set forth by the Supreme Court in Chevron U.S.A. v. National

Resources Defense Council

, 467 U.S. 837, 104 S. Ct. 2778 (1984).

First, the Court determines whether Congress "has directly spoken

to the precise question a t issue. If the intent of Congress is

clear, that i s the end of that matter; for the court, as well as

the agency, must give effect to the unambiguously expressed intent

of Congress ." I d. at 842-43, 104 S. Ct. at 2781. Second, if

Congress has not directly addressed the precise question at issue,

the Court asks whether the agency’s interpretation "is based on a

permissible construction of the statute." Id. at 843, 104 S. Ct. at

2782. As long as the agency’s construction of an ambiguous statute

is permissible, it must be upheld. Id. See also America Forest and

Paper Ass’n v. EPA

, 137 F.3d 291, 297 (5th Cir. 1998) (applying the

Chevron test to the EPA’s interpretation of the CWA).

B.

The question at issue here is whether the EPA has the

authority under t he CWA to set different effluent limits for

different point sources within a single categor y or subcategory.

Alaska Petitioners contend that Congress has already dir e ctly31

answered this question in the negative. They point to the text,

legislative history, and structure of the CWA in support of this

argument. None of the support they provide, however, amounts to a

direct statement by Congress on this issue.

We find nothing in the text of the CWA indicating that

Congress intended to prohibit the promulgation o f different

effluent limits within a single category or subcategory of point

sources. Alaska Petitioners point to tw o sections of the CWA,

neither of whic h is availing on this question. Section 301(b)(2)

requires that ELGs be established for "categories and classes" of

point sources, 33 U.S.C. § 1311(b)(2), while Section 304(b)(2)(B)

mandates that the BAT factors be applied "within such categories or

classes," 33 U.S.C. § 1314(b)(2)(B). These sections do not express

a clear congressional intent on the question at issue here. The

fact that the EPA must promulgate rules for classes of polluters

rather than individual polluters does not mean that the EPA is

required to treat all polluters within each class identically. The

phrases "for categories and classes" and "within such categories or

classes" simply do not, by their terms, exclude a rule allowing

less than perfect uniformity within a category or subcategory.

The legislative history also falls short of expressing a clear

congressional intent to prevent differentiated treatment of point

sources within a category or subcategory. Alaska Petitioners cite

numer ous quotations from the legislative history emphasizing the

importance of national uniformity and categorical rather than

individual treatment of point sources within each category or32

class. See

, e.g.

, A Legislative History of the Water Pollution

Control Act Amendments of 1972 at 172, Cong. Research Service,

Comm. Print No. 1, 93d Cong., 1st Sess. (1973) ("The Conferees

intend that the factors described in section 304(b) be considered

only within classes or categories of point sources and that such

factors not be considered at the time of the applicat ion of an

effluent limita tion to an individual point source within such a

category or class."). At best, however, these quotations s imply

reinforce the textual mandate of the CWA that ELGs be established

for "categories and classes" rather than individual point sources.

Nothing in the quoted excerpts, nor anywhere else in the

legislative history or case law, suggests that Congress intended to

deny the EPA discretion to set different limits for different point

sources within the same category or subcategory when circumstances

so warrant. As our sister court noted in Natural Resources Defense

Council v. EPA

, 859 F.2d 156 (D.C. Cir. 1988): "[N]ot hing in all

this sp ecifies that the EPA m ust apply these uniform guidelines

uniformly to all point sources within industry categories, no

matter what.

. . . [A]lthough exalting the value of uniformity, the

statute simply does not require uniformity in all circumstances."

Id. at 200-201.

Finally, nothing in the structure of the CWA suggests that

Congress intended to prevent the EPA from pro mulgating different

effluent limits for different point sources in a single category or

subcategory. Alaska Petitioners argue that the CWA contains a33

number of carefully enumerated exceptions to the uniformity

r equirement, s ee 33 U.S.C. § 1311(c),(g)-(h),(m)-(n), and that

these exceptions are the exclusive mechanismfor avoiding that

requirement. They cite the long-established canon of statutory

construction that "[w]here Congress specifically enumerates certain

exceptions to a general prohibition, additional exceptions are not

to be implied, in the absence of evidence of a contrary legislative

intent." Andrus v. Glover Const., Inc. , 446 U.S. 608, 616-17, 100

S. Ct. 1905, 1910 (1980). This argument misses the mark. The

question here is not whether the EPA may create a new exception to

the CWA, but rather whether its plenary rulemaking authority under

the CWA includes the power to set different effluent limits for

different point sources in the same category or subcategory. If the

EPA has such authority, then no " general prohibition" exists, so

the Andrus canon is never implicated. Thus, while the structure of

the CWA may express a clear congressional intent to exclude

unenumerated exceptions, it does not speak to the scope of the

EPA’s plenary rulemaking authority under the CWA.

C.

The remaining question, then, is whether the EPA’s decision to

set more lenient effluent limits for Cook Inlet facilities than for

other members of the Coastal S ubcategory reflects a permissible

interpretation of the CWA. We conclude that it does.

As discussed above, nothing in the text, legislative history,

or structure of the CWA suggests that Congress intended to deny the

EPA discretion to set different effluent limits within a category34

or subcategory when circumstances so require. We agree that

Congress intended to foreclose plant-by-plant evaluation of

facilities within a subcategory. But this does not mean that

Congress wished to hamstring the EPA by requiring it to go through

formalistic subcategorization procedures every time it found

genuine differences between groups of point sources within a longestablished category or subcategory. In fact, precedent sug gests

that Congress sought to avoid just this sort of administrative

headache.

The Supreme Court has repeatedly emphasized the importance of

balancing the CWA’s uniformity interest with the practical reality

of differences within a category. These statements have most often

arisen in the context of after-the-fact variances, beginning with

E.I. du Pont de Nemours & Co. v. Train

, 430 U.S. 112, 97 S. Ct. 965

(1977). In du Pont , the Supreme Court was faced with the issue of

whether the EPA was perm itted to establish categorical effluent

limitations, or whether it was required to establish effluent

limitations for individual plants. The Court held that the EPA may

establish categorical limit ations "so long as some allowance is

made for variations in individual plants, as EPA has done by

including a variance clause in its 1977 limitations." Id. at 128,

97 S. Ct. at 975. Notably, the Court did not hold that the EPA is

required to establish categorical effluent limitations, nor did it

hold that variances are the only appropriate way to account for

variations in individual plants. It merely stressed the importance

of balancing uniformity and individual variation.35

The Court elaborated on this statement in Chem. Mfrs. Ass’n v.

Natural Resources Defense Council

, 470 U.S. 116, 105 S. Ct. 1102

(1984), where it approved the fundamentally-different-factor

("FDF") variance procedure "as a mechanism for insuring that [the

EPA’s] necessarily rough-hewn categories do not unfairl y burden

atypical plants." Id. at 120, 105 S. Ct. at 1105. The Court again

emphasized the importance of tempering uniformity with flexibility:

Acting under stringent timetables, EPA must collect and

analyze large amounts of technical information concerning

complex industrial categories. Understandably, EPA may not be

apprised of and will fail to consider unique factors

applicable to atypical plants during the categorical

rulemaking process, and it is thus i mportant that EPA’s

nationally binding categorical pretreatment standards for

indirect dischargers be tempered with the flexibility that the

FDF variance mechanism offers . . . .

Id. at 132-33, 105 S. Ct. at 1111-12.

Although the du Pont and Chem. Mfrs. Ass’n opinions confined

their analyses to the context of variances, the reasoning of those

two cases is applicable in the present case. The EPA is authorized-

-indeed, is required--to account for substantial variations within

an existing category or subcategory of point sources.

Administrative procedures that avoid the costs and burdens

associated with categorical rulemaking are a valuable tool in

fulfill ing that obligation. Where the variations are discovered

after rulemaking is complete, the Supreme Court h as endorsed FDF

variances as the appropriat e procedure. Where the variations are

disco vered before rulemaking is complete, however, FDF variances

are inappropriate. In the absence of any clear congressional intent

to the contrary, we are satisfied under the facts of this case that36

the promulgation of different effluent limits within a single

category or subcategory of point sources provides an acceptable

alternative to subcategorization.

Here, the EPA was faced with a situation in which one group of

point sources within a long-established subcategory was

dramatically different from all oth er point sources within that

subcategory. The EPA found, based on the different geograph y and

circumstances of Cook Inlet, that the cost of complying with a zero

discharge stand ard on produced water or drilling wastes would be

substantially higher for Cook Inlet facilities than for the rest of

the Coastal Subcategory. Thus, the EPA was faced with a stark

choice between conducting administratively burdensome and timeconsuming subcategorization procedures that would have disrupted a

well-established subcategorization scheme or exercising its plenary

rulemaking authority to set different effluent limits within the

Coastal Subcategory. Rather than disrupting its longstanding

subcategorization scheme, creating needless confusion and

unnecessary restructuring, the EPA chose the administratively

efficient route. In doing so, the EPA did not in any way avoid its

ordinary procedural obligations: The Cook Inlet ELGs were subject

to the same notice and comment procedures as the other Coastal

Subcategory ELGs. In light of du Pont and Chem. Mfrs. Ass’n

, we

cannot say that the EPA’s actions were unau thorized. As such,

pursuant to the Chevron test and under the unique fac ts of this

case, we uphold the EPA’s actions with respect to Cook Inlet.

VI.10 Attorney Liz Bill s addressed this issue on behalf of the

Texas Petitioners:

Q: What difference does i t make if we decide this general

permit limitation question?

A: Well, Your Honor we believe-- one of the concerns we have

is an anti-backsliding provision that’s found in the

Clean Water Act that says that once somebody’s been

subject to a certain level of limitations in a permit,

then any subsequent permits that are ever issued can

never have a less stringent limitation, and you can’t get

less stringent than zero.

Q: Well, if we uphol d the rules for the coastal category

then our holding on [the General Permit] is moot--

A: Right. We have to overcome several obstacles, including

the ELGs as well as the General Permit, to get to

something less than zero discharge.

37 In light of our decision to uphold the ELGs’ zero discharge

limits, all issues pertaining to the General Permit are moot. A

case is moot where "the issues presented are no longer live or the

parties lack a legally cognizable interest in the outcome." Powell

v. McCormack

, 395 U.S. 486, 496, 89 S. Ct. 1944, 1951 (1969). Here,

even if we were to review and remand the General Permit, any

subsequent NPDES permit determinati on would be governed by the

ELGs, 33 U.S.C. § 1311(b), so the final result would be unchanged.

Because the zero discharge limit contained in the General Permit is

thus not "susceptible to some judicial remedy," Texas Petitioners

no longer have a "legally cognizable interest" in the outcome of

the General Permit challenge. Baccus v. Parrish , 45 F.3d 958, 961

(5th Cir. 1995). Petitione rs conceded as much at oral argument. 1 0

We therefore need not, and do not, decide whether we have subject

matter jurisdiction to review Texas Petitioners’ delayed challenge

to the General Permit, nor whether Region 6 acted arbitrarily or38

capriciously or abused its discretion when it issued the General

Permit.

VII. CONCLUSION

We hold that the EPA did not act arbitrarily or capriciously

or abuse its discretion when it set zero discharge limits on

produced water and produced sand in the ELGs, that the EPA did not

act contrary to the intent of the CWA when it set separat e

discharge limits on produced water and drilling wastes for Cook

Inlet without designating it a separate subcategory, and that Texas

Petitioners’ chall enge to the General Permit is moot. For these

reasons, all petitioners’ Petitions for Review of Orders of the

Environmental Protection Agency are

DENIED.