UNITEDSTATESENVIRONMENTALPROTECTIONAGENCY REGIONI J.F.KENNEDYFEDERALBUILDING,BOSTON,MASSACHUSETTS02203-2211

November 3, 1988 stephen

## w. Groves, Director Bureau ofWater Quality Control state ofMaine Department of Environmental Protection stateHouse Station 17 Augusta, Maine 04333 Re: Proposed Changes to 38 M.R.S.A. §§ 363-C and 464(4)(F)(1) and Related Matters DearMr. Groves: By letter dated May 21, 1987, the Environmental Protection Agency ("EPA") disapproved, pursuant to Section 303 of the Clean Water Act, 33

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. § 1313, and the regulations promulgated thereunder at 40 C.F.R. Part 131, the following sections of the Maine's Water Quality Standards: 38 M.R.S.A. § 464(F)(1) (Definition of "existing use"); and 38 M.R.S.A. § 363-C (Reclassification of proposed hydroelectric impoundments to Class GP-A). In ourMay 21st letter, we also requested that the DEP provide written assurance that itwould make other specified changes to 38 M.R.S.A. §§ 464(4)(F)(5) and 465(2)-(4) during its next water quality review and provide an interpretation of 38 M.R.S.A. § 467(1)(A)(2) and 467(7)(A)(3) from the Maine Attorney General's Office. On November 25, 1987, the Maine Department of Environmental Protection ("DEP") sent EPA proposed changes to 38 M.R.S.A. §§ 363-C and 464(4)(F)(1). Consistentwith the informal comments provided to the DEP on April 10, 1988, EPA's position with respect to theseproposed changes is set forth below. Maine has also recently proposed regulations which implement certain provisions of the Maine Water Quality Standards. Chapter 587 of these regulations directly relates to the definition of existing use proposed by the State in Section 464(4)(F)(1). We have therefore included comments on this regulation as well. 1. Section 464CFl(1) (Definition of "ExistingUse"): The definition of "existinguse" in the proposed revision to Section 464(F)(1) ismissing certainkey language which is in the federal definition of that term at 40 C.F.R. § 131.3(e).-2- Specifically, the federal index date of "November 28, 1975"-- which is inMaine's currentversion of Section 464(F)(1)--is omitted in the proposed revision. This date or, if preferred, an earlier date, must be included in the State's definition of "existinguse
." In addition, the proposed definition does not provide that uses are existing "whether or not they are included in the water quality standards." Such language must be added to the State's definition so it is clear that a use may be existing even though it is not a designated use underMaine's Water Quality Standards

. The proposed revision also includes language which is inconsistent with the federal antidegradation policy. Specifically, the revision states that "factual determinations of what constitutes an existing in-streamwater use on a particular water body and the extent of allowable impact on the existinguse shall be made on a case-by-casebasis•••" (Emphasis added). The phrase "and the extent of allowable impact on the existing use" must be deleted since it indicates that existinguses will not be fully maintained and protected as required by federal law. Unless the changes noted above are made, the statutoryprovision will not be approvable. In the proposed definition of "existing use," Maine has also listed specific criteria for the State to examine in making caseby-case determinations of "what constitutes an existing in-stream water use on a particularwater body." The recently proposed regulations in Chapter 587.1 of the Bureau ofWater Quality Control Regulations expands on the criteria the Board will examine

. In general, this approach of including the criteria the State will examine in determiningwhether a use is "existing" in the State's definition of "existinguse," is acceptable to EPA. It is not clear, however, if, based on the specific criteria the State has chosen, all the uses that would be considered "existing" under the federal definition would also be considered "existing" under the State'sdefinition. In particular, since the criteria listed inboth the proposed statutoryprovision and the regulation emphasize the length and number of times a use has occurred, EPA is concerned that the State could determine that a particular use was not "existing" because such a use was not currently occurring ordocumented as occurring even though thewater quality was suitableto allow such a use to occur
. For example, the statemight improperly determine that "shellfishing" is not an existing use in an area where shellfish are propagating and surviving and are suitable for harvesting simply because the shellfish are not currently being harvested. See, EPA's "Questions and Answers on Antidegradation," datedAugust, 1985

. Therefore, although EPA would not disapprove Section 464(F)(1) as proposed, we do recommend that Maine add language to eitherthe statute or the-3- regulations that wouldmake it clear that the State will take into account whether the existingwater quality is suitable to allow certainuses to occur even though theymay not be currently occurring. Furthermore, the criteria the statehas chosen to include in Chapter 587.1 relate primarily to "human uses" such as boating, swimming, fishing, etc

. SinceMaine's Water Quality Standards specifically designate "habitat for fish and other aquatic life" as a use, EPA also recommends that additional criteriabe developed which relate to the "aquatic life use
." This could include reports or testimonywhich document the species of fish in a particularwaterbody, or habitat suitability information confirming that certain aquatic uses could occur in a waterbody in the absence of testimony. The proposed regulations in Chapter 587 also raise a question regarding the State's antidegradation policy. Under the federal anti-degradation policy, any proposed discharge whichwould cause a lowering of water quality requires a demonstration of "important economic and social benefits

." 40 C

.F.R. § 131.12(a)(2). EPA's currect view is that, if a discharge will not "significantly" lowerwater quality, the antidegradation requirements will be met and a detailed economic and social benefit analysis need not be performed. Since there is no EPA national guidance identifying a single acceptable method for determining whether a discharge is significant, the Region has proposed that the definition of "significant" be leftup to the states, subject to EPA approval. Under the proposed Chapter 587.5.8., Maine has chosen to operate "under the rebuttable presumption that •lowering of the existing quality of any water body' will occur when a proposed discharge or activity consumes greaterthan 20% of the remaining assimilative capacity allowed in the appropriate class

." Thus, all discharges belowthe 20% cutoffwould automaticallybe determined to be "insignificant." Such an approach could have results which are contrary to the federal antidegradation policy since repeated or small discharges below the 20% cutoff could result in significantwater quality degradation without a demonstration of economic and social benefit. For this reason the Region finds that the proposed regulation, as drafted, may not be approvablewithout changes. Until national policy on this issue is established, the Region would find this provision acceptable if it is redrafted in the following manner: First, the regulation should be changed so that all discharges greater than 20% of the remaining assimilative capacity wouldbe automatically deemed "significant."-4-
Second, the regulation should provide that all discharges less than the 20% cutoffwill be subject to a case-by-case review by the State to determine whether or not the discharge is significant. In examining each discharge on a case-by-case basis, the State will consider certain listed criteria such as the degree of degradation that has been permittedpreviously, the sensitivity of the particular waterbody, etc. Finally, the regulation should state that notice of the state finding of significance or insignificance and an opportunity to comment on such finding will be included in the public notice of the permit proposed to be issued to the discharger.

2

. 38 M.R

.S.A

. § 363-C (Reclassification of Proposed Hydroelectric Impoundments The proposed provisions on state certification and dam licensing are acceptable but the statemust clarify Section 635-B(l)(C) so that it isunderstood that it is the change in the characteristics of the waterbody both upstream and downstream resulting from the proposed dam that must not violate Section 464(4)(F)

. 3. Other Issues To date EPA has not receivedwritten assurances that the State will incorporate specific requirements on nonpoint source control in 38 M.R

.S.A. § 464(4)(F)(5) or include dissolved oxygen criteriaprotective of salmonid spawning in 38 M

.R.S.A. § 465(2)-(4) as required by EPA's May 21, 1988 letter referred to above. These written assurances should be submitted to the agency as soon as possible. In addition, EPA has not received an interpretation of 38 M.R.S.A. § 467(1)(A)(2) and 467(1)(A)(3) from the Maine Attorney General's Office. The Region recognizes that the Statehas been following the interpretationput forth by EPA in itsMay 6th letter regarding these two provisions. However, until this interpretation is confirmed by the Attorney General, the provision is subject to alternative interpretations in the future which may not be consistent with federal requirements. For this reason, the statemust either remove the language in question from the statute or submit a formal Attorney General's Statement which indicates that it is being read consistently with federal requirements.-5-
Please feel free to call Eric Hall ofmy staff or Tonia D. Bandrowicz orJonathan Kaledin of the Office of Regional counsel ifyou have any questions regarding this matter. Mr. Hall can be reached at (617) 565-3533. Mr

. Kaledin can be reached at (617) 565-3334. Ms

. Bandrowicz will be on detail to EPA's Washington D.C

. Office until February, 1989 but can be reached at (202) 475-8180. Sincerely,

# ~ David A

. Fierra, Director Water Management Division

cc: Ron Kriesman, Natural Resources Council, Maine David K. Sabock, WH-585 Jonathan Kaledin, RRC-2203