IDAHO MIN. ASS'N, INC. v. Browner

ORDER RULING ON CROSS-MOTIONS FOR SUMMARY JUDGMENT

The following motions are currently before the Court for its consideration: (1) Plaintiff Idaho Mining Association’s Motion for Summary Judgment (Docket # 16), filed March 19,1999; and (2) Defendants’ Motion for Summary Judgment (Docket #27), filed May 10, 1999. On September 1, 1999, the Court conducted a hearing on the pending motions with counsel for all parties appearing and participating. The Court has considered the arguments of counsel and has fully reviewed the legal briefing and other pertinent documents of record and is now prepared to enter its ruling on the pending motions as follows.

I. Background

In the instant action, the Court is asked to determine whether the Environmental Protection Agency (“EPA”) exceeded its authority under the Administrative Procedures Act (“APA”), 5 U.S.C. § 551, et seq., and the Clean Water Act (“CWA” or “Act”), 33 U.S.C. § 1251, et seq., when it promulgated a rule establishing revised water quality standards for three (3) water body segments in Northern Idaho. Plaintiff, Idaho Mining Association, challenges the revised standards and seeks a declaration from this Court that the EPA’s rule-making was arbitrary and capricious, an abuse of discretion and otherwise not in accordance with the law. Plaintiff also seeks an order vacating the challenged rule and remanding the matter back to the EPA for further proceedings in accordance with the requirements of the APA and CWA.

A. The Clean Water Act

The primary objective of the Clean Water Act (“CWA”) is to “restore and maintain the chemical, physical, and biological integrity of the Nation’s waters” through the implementation of goals and policies designed to eliminate the discharge of pollutants into these waters. Section 101(a), 33 U.S.C. § 1251(a). To this end, Congress has declared that “wherever attainable, an interim goal of water quality which provides for the protection and propagation of fish, shellfish, and wildlife and provides for recreation in and on the water be achieved.” Section 101(a)(2), 33 U.S.C. § 1251(a)(2). These so-called “fish-able/swimmable” uses are primarily achieved through the implementation of two mechanisms: (1) technology-based requirements, i.e. “effluent limitations guidelines;” and (2) water-quality based requirements, i.e. water quality standards. See Sections 301 and 303, 33 U.S.C. §§ 1311 and 1313.

Technology-based requirements impose stringent limitations upon the types and amounts of pollutants which may be discharged into the nation’s waters by point sources. 1 Section 301, 33 U.S.C. § 1311. Water quality-based requirements, on the other hand, specify the desired condition of a waterway in terms of the standard (i.e. fishable/swimmable, agricultural, industrial, etc.) to be achieved. Section 303, 33 U.S.C. § 1313. Thus, water quality standards generally consist of three elements: (1) one or more designated uses for the water body at issue; (2) water quality criteria which express the concentrations or levels of pollutants which may be present in the water and still support the designated use(s); and (3) an anti-degradation policy. Section 303(c)(2), 33 U.S.C. *1081 § 1313(c)(2); Section 303(d)(4)(B), 33 U.S.C. § 1313(d)(4)(B); 40 C.F.R. § 131.3(i). As the United States Supreme Court has explained, water quality standards “supplement effluent limitations ‘so that numerous point sources, despite individual compliance with effluent limitations, may be further regulated to prevent water quality from falling below acceptable levels.’ ” Arkansas v. Oklahoma, 503 U.S. 91, 101, 112 S.Ct. 1046, 1054, 117 L.Ed.2d 239 (1992) (quoting EPA v. California ex rel. State Water Resources Control Bd., 426 U.S. 200, 205 n. 12, 96 S.Ct. 2022, 2025, n. 12, 48 L.Ed.2d 578 (1976)).

While both effluent limitations guidelines and water quality standards are useful tools in improving the condition of the nation’s waters, neither alone is sufficient to ensure compliance with the requirements of the CWA. Thus, Congress created the National Pollutant Discharge Elimination System (“NPDES”) as a means of enforcing the limitations and standards imposed by the Act. Section 402, 33 U.S.C. § 1342. Under the NPDES, individuals must obtain a permit in order to discharge pollutants into the waters of the United States. Section 301(a), 33 U.S.C. § 1311(a) (prohibiting the discharge of any pollutant by any person except as permitted by certain provisions of the CWA, including section 402). An NPDES permit sets forth certain terms and conditions with which individual dischargers must comply and “serves to transform generally applicable effluent limitations and other standards including those based on water quality into the obligations ... of the individual discharger .... ” State Water Resources Control Bd., 426 U.S. at 205, 96 S.Ct. at 2025.

Under the CWA, individual states are primarily responsible for the prevention, reduction and elimination of pollution of waterways within their boundaries. Section 101(b), 33 U.S.C. § 1251(b). This responsibility carries with it the obligation to promulgate water quality standards consistent with the purposes and requirements of the CWA. Section 303(c), 33 U.S.C. § 1313(c). 2 Specifically, section 303(c) of the CWA requires that each state periodically undertake a public review of existing water quality standards and revise and adopt new standards as appropriate. 33 U.S.C. § 1313(c)(1). In adopting and/or revising water quality standards, each state is required to specify the appropriate water uses to be achieved and protected, taking into consideration the particular water body’s “use and value for public water supplies, propagation of fish and wildlife, recreational purposes, and agricultural, industrial, and other purposes, and also taking into consideration their use and value for navigation.” Section 303(c)(2)(A), 33 U.S.C. § 1313(c)(2)(A); 40 C.F.R. § 131.10(a). Furthermore, each state is required to adopt water quality criteria, expressed in terms of numerical values or narrative criteria, to protect the designated use(s). 40 C.F.R. § 131.11.

The CWA does not impose upon states the obligation to designate any particular use(s) for water bodies. At a minimum, however, states must revise their water quality standards to reflect existing uses, i.e. those uses which are actually being attained. 40 C.F.R. § 131.10(i); 40 C.F.R. § 131.10(e). Furthermore, fisha-ble/swimmable uses are favored. Section 101(a)(2), 33 U.S.C. § 1251(a)(2). Thus, where a state fails to designate a water body for fishable/swimmable uses, the state must conduct a use attainability analysis (“UAA”) in accordance with the provisions of the CWA. 3 40 C.F.R. § 131.10(j)(l). Conversely, a UAA is not *1082 required whenever físhable/swimmable uses are designated. 40 C.F.R. § 131.10(k).

Although it is the states’ responsibility to develop and/or revise water quality standards for waters within their boundaries, such new or revised standards must be submitted' to the EPA for approval. Section 303(c)(2)(A), 33 U.S.C. § 1313(c)(2)(A). The EPA implementing regulations set forth the minimum requirements for water quality standards submissions as follows:

The following elements must be included in each state’s water quality standards submitted to EPA for review:

(a) Use designations consistent with the provisions of Sections 101(a)(2) and 303(c)(2) of the Act.

(b) Methods used and analyses conducted to support water quality standards revisions.

(c) Water quality criteria sufficient to protect the designated uses.

(d) An antidegradation policy consistent with § 131.12.

(e) Certification by the State Attorney General or other appropriate legal authority within the State that the water quality standards were duly adopted pursuant to State law.

(f) General information which will aid the Agency in determining the adequacy of the scientific basis of the standards which do not include the uses specified in Section 101(a)(2) of the Act [i.e. fisha-ble/swimmable uses] as well as information on general policies applicable to State standards which may affect their application and implementation.

40 C.F.R. § 131.6. If the EPA rejects a state’s proposed water quality standards, it must so notify that state within ninety (90) days and specify the changes necessary to meet CWA requirements. Section 303(c)(3), 33 U.S.C. § 1313(c)(3). If, within ninety (90) days after notification, the state fails to make such changes, the EPA is required to “promptly prepare and publish proposed regulations setting forth a revised or new water quality standard for the navigable waters involved.” Section 303(c)(4)(A), 33 U.S.C. § 1313(c)(4)(A); 40 C.F.R. § 131.22(a). In doing so, the EPA “is subject to the same policies, procedures, analyses, and public participation requirements established for States in [the EPA] regulations.” 40 C.F.R. § 131.22(c).

B. Procedural History

Plaintiff, Idaho Mining Association, is a non-profit corporation whose members include industrial facilities that conduct mining activities in the State of Idaho. Plaintiffs members hold National Pollutant Discharge Elimination System (“NPDES”) permits and are authorized to discharge certain amounts of industrial wastewater to particular waters in Northern Idaho. On October 2, 1998, Plaintiff filed a Complaint in the instant action naming the United States Environmental Protection Agency and the following individuals as defendants: Carol M. Browner, Administrator, U.S. Environmental Protection Agency; and Charles C. Clarke, Regional Administrator, Environmental Protection Agency, Region 10 (hereinafter collectively referred to as “EPA”). In its Complaint, Plaintiff alleges that the EPA failed to comply with the requirements of the APA when it promulgated revised water quality standards for certain Idaho waters in 1997. The revised standards establish new designated uses for certain stream segments in Northern Idaho and impose more stringent water quality criteria to protect the new uses. Plaintiff alleges that the new standards will significantly affect the ability of Plaintiffs members to discharge mining pollutants into the affected waters pursuant to their NPDES permits and will negatively impact the economic viability of the mining industry in Idaho. Plaintiff seeks an order vacating that portion of the EPA rule which establishes the new designated uses on the grounds that the EPA rulemaking as to the revised standards was arbitrary and *1083 capricious, an abuse of discretion and other-wise not in accordance with the law.

On December 18, 1998, the Idaho Conservation League and the Lands Council (hereinafter collectively referred to as the “Conservation Groups”) filed a Motion to Intervene. (Docket # 8). The Conservation Groups are non-profit organizations which are highly active in seeking to improve Idaho water quality standards and to protect the aquatic life and human uses of Idaho’s rivers, lakes and streams. On April 19, 1999, the Court granted the Conservation Groups’ Motion to Intervene on the grounds that they have a significant interest in defending the improved water quality standards which Plaintiff now challenges. (Docket # 23).

The action is presently before the Court on Plaintiff and Defendants’ cross-motions for summary judgment. The Conservation Groups have not filed a motion for summary judgment but have formally joined in Defendants’ motion, see Docket # 32, and have filed a separate brief in support of their position.

C. Factual History

The material facts underlying this matter are not in dispute. On July 11, 1994, the State of Idaho fulfilled its obligations under section 303(c) of the CWA by submitting a complete set of water quality standards to the EPA for review. (IWQS 0784). Almost two years later, on June 25, 1996, the EPA issued an official notification approving Idaho’s 1994 water quality standards with certain exceptions. (IWQS 00021). However, this notification came only after the Conservation Groups filed a citizen suit against the EPA to compel it to comply with its mandatory duties under sections 303(c)(3) and 303(c)(4)(A) of the CWA to formally approve or disapprove Idaho’s proposed water quality standards and, if necessary, to adopt replacement standards for those state standards which it disapproved. See Idaho Conservation League v. Browner, 968 F.Supp. 546 (W.D.Wash.1997) (hereinafter “ICL v. Browner ”).

One group of standards which the EPA disapproved in its June 1996 letter concerned the designation of 53 Idaho stream segments for uses less protective than fish-able/swimmable. 4 (IWQS 00024). Specifically, the EPA informed the IDEQ that the following disapproval issue would require immediate state action:

Stream Segments with Specific Use Designations which a,re Inconsistent with Clean Water Act Requirements EPA disapproves the classification of waters of the State listed in 16.01.02.102 through 16.01.02.160 of the Idaho 1994 Water Quality Standards which do not include uses specified in CWA § 101(a)(2) and the requirements of CWA § 303(b)(2) and 40 C.F.R. § 131.10....

(IWQS 00024). In a separate memorandum, the EPA further explained its disapproval decision as to the classification of waters which did not include uses specified in section 101(a)(2) of the CWA. (IWQS 00027-00030). That memorandum stated in part:

The goals and requirements of the Act, are that wherever attainable, water quality shall provide for the protection and propagation of fish, shellfish, and wildlife and provide for recreation in and on the water. Where the State designates or has designated uses that do not include the uses specified in CWA § 101(a)(2) the federal water quality standards regulation requires States to conduct and submit to EPA a use attainability analysis.

(IWQS 00028).

Having disapproved Idaho’s use designations for the specified stream segments, and consistent with its obligations under *1084 section 303(c)(3) of the CWA, the EPA informed the IDEQ that it must undertake certain revisions in order to bring Idaho’s 1994 water quality standards in conformity with the purposes and requirements of the CWA. (IWQS 00022). In this respect, the EPA provided the IDEQ with two options, either of which it determined to be an appropriate resolution to remedy the deficient water quality standards:

The State can either a) conduct and submit to EPA acceptable use attainability analyses to justify the existing classification for the above listed water bodies, or b) adopt designated uses for each water body which provides for the protection and propagation of aquatic life and recreation in and on the water where applicable.

(IWQS 00030). However, Idaho failed to undertake either of these revisions within the ninety (90) day time period prescribed by section 303(c)(4)(A) of the CWA. Thus, it became the EPA’s responsibility to “promptly prepare and publish” replacement standards in accordance with the CWA. Section 303(c)(4)(A), 33 U.S.C. § 1313(c)(4)(A); 40 C.F.R. § 131.22(a).

By February, 1997, neither the IDEQ nor the EPA had promulgated new or revised water quality standards for Idaho. Consequently, the Conservation Groups took it upon themselves to seek a court order requiring the EPA to adopt replacement standards in accordance with its duties under section 303(c)(4)(A) of the CWA. On February 20,1997, the presiding judge in ICL v. Browner, granted the Conservation Groups’ motion for summary judgment and entered an order directing the EPA to act within sixty (60) days to “promulgate water quality standards for Idaho in accordance with its June 1996 letter of disapproval.” ICL v. Brouwer, 968 F.Supp. at 549. The court order was subsequently modified to allow the EPA sixty (60) days in which to propose revised standards and ninety (90) days thereafter in which to promulgate a final rule. (IWQS 07842,17843).

On April 28, 1997, the EPA published a proposed rule introducing several tentative revisions to those Idaho water quality standards which the EPA had disapproved in 1996. 62 Fed.Reg. 23,003 (April 28, 1997); (IWQS 07841-07867). Included within the proposed revisions was a new federal use designation establishing aquatic life and recreation uses for the specific water body segments whose use designations EPA had disapproved in 1996. (IWQS 07846). The EPA explained that it had previously disapproved Idaho’s regulations with respect to those waters because, in many cases, the regulations only protected the stream segments for recreation and did not provide any protection for aquatic life. (Id.). The EPA determined that Idaho’s failure to adopt water quality standards which provided protection for the fishable component of fishable/swimmable uses was inconsistent with the goals and requirements of the CWA because Idaho had not undertaken a UAA to demonstrate that such uses were unattainable. (IWQS 07844, 07846). Thus, the EPA proposed to promulgate a rule establishing aquatic life and recreation designated uses for the water body segments of concern, unless it was demonstrated to the EPA for a particular water body that such uses were unattainable. (IWQS 07846-07847). In proposing this rule, the EPA expressly stated that it was relying on a rebuttable presumption implicit in its regulations at 40 C.F.R. Part 131 that fishable/swimma-ble uses are attainable unless the uses have been shown by a UAA to be unattainable. (IWQS 07844, 07846, 07853). In addition, the EPA specifically proposed that 35 of the 53 stream segments be designated for cold water biota use because “[t]he majority of native Idaho fish are classified as cold water species and the presence of the species occurs throughout the entire State.” (IWQS 07845, 07847).

The EPA held a public hearing and took comments on all aspects of the proposed rule for a period of thirty (30) days. (IWQS 04857). Many commentators com *1085 plained that the comment period was too short. (Id.). However, in responding to the comments, the EPA explained that none of the commentators had demonstrated that the thirty (30) day comment period was inadequate as a matter of law. (Id.). Moreover, the EPA noted that an extension of the comment period was not feasible because the EPA was under a strict court-ordered deadline to promulgate the final rule by July 31, 1997. (Id.). In addition to raising procedural concerns, commentators also voiced general objections to the EPA’s cold water biota use designations for the water bodies at issue. (IWQS 04860). However, after reviewing the information submitted, the EPA concluded that the data did not demonstrate that the aquatic life uses — and specifically, the cold water biota uses — could not be attained.

On July 31, 1997, the EPA published the final rule establishing cold water biota designated uses for several Idaho waterways, including the South Fork of the Coeur d’Alene River and two of its tributaries, Canyon Creek and Shields Gulch (hereinafter collectively referred to as the “affected waters”). 5 See 40 C.F.R. § 131.33(b). In doing so, the EPA again stated that it was “relying on the rebuttable presumption implicit in the CWA and EPA’s regulations at 40 C.F.R. part 131, that in the absence of data to the contrary, ‘fishable’ uses are attainable.” (IWQS 04860).

In promulgating the final rule, the EPA made clear that a discharger with an existing NPDES permit is not subject to permit conditions reflecting the heightened water quality standards for the affected waters until such time as the discharger’s permit is renewed. (IWQS 04872). However, the EPA recognized that additional data material to the attainability of the cold water biota uses might become available in the future. (IWQS 04871, 07853). Thus, the EPA rule also established a procedure by which an individual dischar-ger can obtain a variance from the water quality standards by demonstrating that the cold water biota use is unattainable due to the presence of certain chemical or physical conditions, or because compliance with the fishable use criteria would cause “substantial and widespread economic and social impact.” 40 C.F.R. § 131.33(d)(3). Pursuant to the variance procedure, application for the water quality standards variance is timed to coincide with the NPDES permit renewal process. 40 C.F.R. § 131.33(d)(4). Thus, an individual NPDES regulated discharger who establishes that the cold water biota use is unattainable for a particular water body will escape the more stringent permit limits imposed by cold water biota use designation. However, the variance applies only to the to the permit holder requesting the variance; the underlying cold water biota use designation otherwise remains in effect. 40 C.F.R. § 131.33(d)(1).

II. Legal Standards

A. Summary Judgment Standard

When reviewing a motion for summary judgment, the proper inquiry is whether “the pleadings, depositions, answers to interrogatories, and admissions on file, together with the affidavits, show that there is no genuine issue as to any material fact and that the moving party is entitled to a judgment as a matter of law.” Fed. R. Civ.P. 56(c) (1993). A moving party who does not bear the burden of proof at trial may show that no genuine issue of material fact remains by demonstrating that “there is an absence of evidence to support the non-moving party’s case.” Celotex Corp. v. Catrett, 477 U.S. 317, 325, 106 S. Ct. 2548, 91 L.Ed.2d 265 (1986). Once the moving party meets the requirement of Rule 56 by either showing that no genuine issue of material fact remains or that there is an absence of evidence to support *1086 the non-moving party’s case, the burden shifts to the party resisting the motion who “must set forth specific facts showing that there is a genuine issue for trial.” Anderson v. Liberty Lobby, Inc., 477 U.S. 242, 256, 106 S.Ct. 2505, 91 L.Ed.2d 202 (1986). It is not enough for the [non-moving] party to “rest on mere allegations of denials of his pleadings.” Id. Genuine factual issues must exist that “can be resolved only by a finder of fact because they may reasonably be resolved in favor of either party.” Id. at 250, 106 S.Ct. 2505.

“When determining if a genuine factual issue ... exists, ... a trial judge must bear in mind the actual quantum and quality of proof necessary to support liability.” Id. at 249-250, 106 S.Ct. 2505. “The mere existence of a scintilla of evidence in support of the [non-moving party’s] position will be insufficient; there must be evidence on which the jury could reasonably find for the [non-moving party].” Id.

The Ninth Circuit has consistently applied the standard for granting summary judgment. Musick v. Burke, 913 F.2d 1390 (9th Cir.1990); Pelletier v. Federal Home Loan Bank, 968 F.2d 865 (9th Cir. 1992); Bieghler v. Kleppe, 633 F.2d 531 (9th Cir.1980).

In determining whether a material fact exists, facts and inferences must be viewed most favorably to the non-moving party. To deny the motion, the Court need only conclude that a result other than that proposed by the moving party is possible under the facts and applicable law. Aronsen v. Crown Zellerbach, 662 F.2d 584, 591 (9th Cir.1981).

The Ninth Circuit has recently emphasized that summary judgment may not be avoided merely because there is some purported factual dispute, but only when there is a “genuine issue of material fact.” Hanon v. Dataproducts Corp., 976 F.2d 497 (9th Cir.1992).

In order to withstand a motion for summary judgment, the non-moving party (1) must make a showing sufficient to establish a genuine issue of fact with respect to any element for which it bears the burden of proof; (2) must show that there is an issue that may reasonably be resolved in favor of either party; and (3) must come forward with more persuasive evidence than would otherwise be necessary when the factual context makes the non-moving party’s claim implausible.

British Motor Car Distrib. Ltd. v. San Francisco Automotive Indus. Welfare Fund, 882 F.2d 371 (9th Cir.1989).

B. Administrative Review Standard

In reviewing an agency’s action overall, the Court follows the provisions of the Administrative Procedures Act (“APA”), 5 U.S.C. § 551, et seq. Specifically section 706(2)(A) of the APA provides that the reviewing court shall “hold unlawful and set aside agency action, findings, and conclusions found to be ... arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with the law .... ” The United States Supreme Court has held that the ultimate standard of review under this provision is narrow, and that a court is not entitled to substitute its judgment for that, of the agency’s. Motor Vehicle Manufacturers Assn. v. State Farm Mut. Ins. Co., 463 U.S. 29, 31, 103 S.Ct. 2856, 2860-2861, 77 L.Ed.2d 443 (1983). At the same time, however, the reviewing court must conduct a review that is “searching and careful.” Mt. Graham Red Squirrel v. Espy, 986 F.2d 1568, 1571 (9th Cir.1993).

In order for an agency’s decision to be upheld, a court must find that “evidence before the agency provided a rational and ample basis for its decision,” otherwise the decision could be held to be arbitrary and capricious. Northwest Motorcycle Assn. v. United States Dept. of Agriculture, 18 F.3d 1468, 1471 (9th Cir.1994). An agency’s own interpretation of its own regulations controls “unless it is plainly erroneous or inconsistent with the regulations.” Nevada Land Action Assn. v. U.S. Forest Service, 8 F.3d 713 (9th Cir.1993). With *1087 this standard in mind, the Court will determine whether the EPA’s decision to promulgate a rule establishing aquatic life designated uses for three water bodies in Northern Idaho based on a rebuttable presumption that such a uses are attainable was arbitrary and capricious, an abuse of discretion, or otherwise not in accordance with the law.

III. Cross-Motions for Summary Judgment

Plaintiff and Defendants each move for summary judgment as to the validity of that portion of the EPA rule which establishes cold water biota use designations for the South Fork Coeur d’Alene River, Canyon Creek and Shields Gulch. See 40 C.F.R. § 131.33(b). Plaintiff contends that the rule was based upon inadequate data and analysis and that the EPA impermissi-bly created and relied upon a rebuttable presumption that the designated aquatic life uses are attainable in the affected waters. Plaintiff also alleges that the EPA’s rulemaking violated the APA in that the EPA failed to consider relevant factors in determining whether aquatic life uses were in fact attainable. Defendants and Inter-venors, on the other hand, assert that the rebuttable presumption of attainability is a permissible interpretation of existing regulations governing water quality standards. Furthermore, Defendants and Tntervenors argue that the EPA rule was neither arbitrary and capricious nor contrary to law because a cold water biota designation for each of the three water bodies at issue is consistent with the purposes and requirements of the CWA. The Court will take up each of these arguments in turn.

A. Whether the EPA’s Reliance Upon a Rebuttable Presumption of Attainability to Support the Aquatic Life Use Designation was Impermissible

Plaintiff argues that the EPA acted unlawfully when it relied upon a rebuttable presumption of attainability to support a cold water biota use designation for each of the three affected waters. Plaintiff advances several arguments as to why it is entitled to judgment as a matter of law as to this issue. In the first instance, Plaintiff contends that neither the CWA nor the EPA’s implementing regulations at 40 C.F.R. Part 131 authorize a presumption that aquatic life uses are attainable unless and until such uses are proved unattainable. Additionally, Plaintiff asserts that the EPA’s adoption of the rebuttable presumption was actually the creation of a substantive rule for which the EPA failed to provide the appropriate notice and comment period as required by the APA. See 5 U.S.C. § 553. Plaintiff also maintains that the EPA’s application of the rebuttable presumption was unlawful because there were insufficient facts on which to base the aquatic life use designation and because there was no meaningful opportunity to rebut the presumption. Finally, Plaintiff asserts that the EPA exceeded its statutory authority in adopting a rebuttable presumption of attainability.

In response, and in support of its own motion for summary judgment, the EPA argues that its reliance on the rebuttable presumption of aquatic life use attainability was a reasonable interpretation of the EPA’s own water quality standards regulations. Specifically, EPA contends that its regulations have always required that waters be designated for fishable/swimmable uses unless a use attainability analysis affirmatively demonstrates that fisha-ble/swimmable uses cannot be sustained. Furthermore, the EPA asserts that even if the fishable/swimmable presumption were a new interpretation of EPA regulations, it is a reasonable interpretation that was developed after the notice and comment period required by the APA. Lastly, the EPA contends that its reliance on the rebuttable presumption was not unlawful because the EPA regulations which it has interpreted as requiring fishable/swimmable use designations reasonably implement the CWA.

The Intervenors have also submitted a brief in opposition to Plaintiff’s motion for *1088 summary judgment and supporting the EPA’s position. In it, they argue that the EPA was under both a statutory and judicial mandate to promulgate aquatic life use designations for the affected waters.

1. Whether the EPA Reasonably Interpreted Its Own Regulations as Requiring a Rebuttable Presumption in Favor of Aquatic Life Use Designations

It is undisputed that one of the primary goals of the CWA is to achieve water quality that provides for fishable/swimma-ble uses wherever such uses are attainable. Section 101(a)(2), 38 U.S.C. § 1251(a)(2). It is further undisputed that when establishing new or revised water quality standards, states are required to adopt standards that “protect the public health or welfare, enhance the quality of water and serve the purposes” of the CWA. Section 303(c)(2)(A), 33 U-S-C. § 1313(c)(2)(A). While these provisions plainly express a preference for fishable/swimmable use designations, all parties agree that the CWA does not itself create a rebuttable presumption that such uses are always attainable. Rather, the CWA directs states to consider numerous factors when adopting water quality standards, including the water body’s “use and value for public water supplies, propagation of fish and wildlife, recreational purposes,” and other purposes enumerated by the Act. Id. See also, 40 C.F.R. § 131.10(a). Nevertheless, the EPA contends that a rebuttable presumption of aquatic fife attainability is clearly supported by EPA regulations implementing the CWA.

The regulatory provisions upon which the EPA relies are codified at 40 C.F.R. §§ 131.10(j) and (k). Specifically, section 131.10(j) provides that a state must conduct a use attainability analysis anytime the state fails to designate a water body for fishable/swimmable uses. Section 131.10(k), on the other hand, provides that a state is not required to conduct a use attainability analysis whenever the state designates fishable/swimmable uses. According to the EPA, the net effect of these two provisions is to require that water quality standards provide for fisha-ble/swimmable uses unless those uses have been shown by a use attainability analysis to be unattainable. This position is entirely consistent with the position taken by the EPA throughout the course of the rule-making process. (IWQS 04860, 07844, 07846, 07853). In fact, the preamble to the proposed rule contains perhaps the most explicit statement to this effect. There, the EPA explained:

EPA’s regulations at 40 C.F.R. Part 131 interpret and implement [sections 101(a)(2) and 303(c)(2)(A) of the CWA] through a requirement that water quality standards provide for fisha-ble/swimmable uses unless those uses have been shown to be unattainable, effectively creating a rebuttable presumption of attainability. Unless that presumption has been rebutted, a default designation of fishable/swimmable beneficial uses apply.

(IWQS 07844). Throughout the administrative process, the EPA consistently relied on the above interpretation of its own regulations to support the challenged rule.

It is well-settled that an agency’s reasonable interpretation of its own regulations is entitled to substantial deference. Arkansas v. Oklahoma, 503 U.S. 91, 112, 112 S.Ct. 1046, 1060, 117 L.Ed.2d 239 (1992) (holding that a court sitting in review of an agency action should give “due regard” to the agency’s interpretation of its own regulations); Udall v. Tallman, 380 U.S. 1, 16, 85 S.Ct. 792, 801, 13 L.Ed.2d 616 (1965) (‘When the construction of an administrative regulation rather than a statute is in issue, deference is even more clearly in order.”); Western States Petroleum Assn. v. Environmental Protection Agency, 87 F.3d 280, 283 (9th Cir. 1996) (“[W]e must give deference to the EPA’s interpretation of its own regulations, if its interpretation is not unreasonable.”). Accordingly, the threshold inquiry *1089 to be resolved on summary judgment is whether the EPA reasonably interpreted its water quality standards regulations as requiring a rebuttable presumption in favor of aquatic life use designations. Plaintiff contends that it did not.

Plaintiff argues that the EPA regulations at 40 C.F.R. Part 131 cannot reasonably be interpreted to authorize a re-buttable presumption of attainability. In support of its position, Plaintiff places much emphasis on the fact that the EPA has “admitted” that this is the first time it has ever relied on such a presumption in promulgating federal water quality standards. However, as the EPA points out, the EPA has merely admitted that this is the first time it has ever used the phrase “rebuttable presumption” in connection with a water quality standards promulgation. (IMA’s Answer, Docket #7, U 23). In fact, the water quality standards on which the EPA bases its interpretation have actually been in existence since 1983 and have always required that waters be designated for fishable/swimmable uses unless a UAA demonstrates that fishable/swimmable uses cannot be attained. See 48 Fed. Reg. 51400, 51405, 51409 (Nov. 8, 1983), codified at 40 C.F.R. §§ 131.10(j) and (k).

The EPA contends that while it has never before used the term “rebuttable presumption,” it has relied upon the concept in previous rulemaking. Specifically, the EPA draws the Court’s attention to a federal -water quality standard which it promulgated for the State of Arizona in 1996. See 61 Fed.Reg. 20686, 20687-88 (May 7, 1996). As in the present case, Arizona had previously submitted its proposed water quality standard revisions to the EPA for review. However, the EPA disapproved the proposed standards on the grounds that Arizona failed to include a “fish consumption” use for certain water bodies which it already designated for aquatic and wildlife use. The Arizona Department of Environmental Quality subsequently submitted UAAs in support of its decision not to include fish consumption uses. However, the EPA was under a court order to promulgate the regulation and stated that it did not have sufficient time to review the data submitted. Consequently, the EPA promulgated a default fish consumption use designation for the water bodies at issue. The EPA explained that it would withdraw the designation if, after completing its review of the UAAs, it determined that the fish consumption use was not feasible.

In responding to comments to the Arizona promulgation, the EPA relied upon its designated use regulations and explained its rationale as follows:

EPA regulations regarding use designations provide that a State “must conduct a use attainability analysis as described in 40 C.F.R. § 131.3(g) whenever the state designates or has designated uses that do not include the uses specified in section 101(a)(2) of the Act.” 40 C.F.R. § 131.10(j)(l). Section 101(a)(2) of the CWA provides that water quality “shall provide for the protection of fish, shellfish, wildlife and recreation in and on the water”, and, in EPA’s view, the “protection” of fish, shellfish, and recreation necessarily includes ensuring that fish are not so contaminated that they are unh