Maine Revised Statutes
Article 4-A: WATER CLASSIFICATION PROGRAM
38 §464. Classification of Maine waters

§464. Classification of Maine waters
(CONFLICT)
The waters of the State shall be classified in accordance with this article. [PL 1985, c. 698, §15 (NEW).]
1. Findings; objectives; purpose. The Legislature finds that the proper management of the State's water resources is of great public interest and concern to the State in promoting the general welfare; in preventing disease; in promoting health; in providing habitat for fish, shellfish and wildlife; as a source of recreational opportunity; and as a resource for commerce and industry.
The Legislature declares that it is the State's objective to restore and maintain the chemical, physical and biological integrity of the State's waters and to preserve certain pristine state waters. The Legislature further declares that in order to achieve this objective the State's goals are:
A. That the discharge of pollutants into the waters of the State be eliminated where appropriate; [PL 1985, c. 698, §15 (NEW).]
B. That no pollutants be discharged into any waters of the State without first being given the degree of treatment necessary to allow those waters to attain their classification; and [PL 1985, c. 698, §15 (NEW).]
C. That water quality be sufficient to provide for the protection and propagation of fish, shellfish and wildlife and provide for recreation in and on the water. [PL 1985, c. 698, §15 (NEW).]
The Legislature intends by passage of this article to establish a water quality classification system which will allow the State to manage its surface waters so as to protect the quality of those waters and, where water quality standards are not being achieved, to enhance water quality. This classification system shall be based on water quality standards which designate the uses and related characteristics of those uses for each class of water and which also establish water quality criteria necessary to protect those uses and related characteristics. The Legislature further intends by passage of this article to assign to each of the State's surface water bodies the water quality classification which shall designate the minimum level of quality which the Legislature intends for the body of water. This designation is intended to direct the State's management of that water body in order to achieve at least that minimum level of water quality.
[PL 1985, c. 698, §15 (NEW).]
2. Procedures for reclassification. Reclassification of state waters shall be governed by the following provisions.
A. Upon petition by any person or on its own motion, the board may initiate, following public notice, and the commissioner shall conduct classification studies and investigations. Information collected during these studies and investigations must be made available to the public in an expeditious manner. After consultation with other state agencies and, where appropriate, individuals, citizen groups, industries, municipalities and federal and interstate water pollution control agencies, the board may propose changes in water classification. [PL 1989, c. 890, Pt. A, §40 (AFF); PL 1989, c. 890, Pt. B, §54 (AMD).]
B. The board shall hold public hearings in the affected area, or reasonably adjacent to the affected area, for the purposes of presenting to all interested persons the proposed classification for each particular water body and obtaining public input. [PL 1989, c. 890, Pt. A, §40 (AFF); PL 1989, c. 890, Pt. B, §54 (AMD).]
C. Pursuant to subsection 3, paragraph B, the board may recommend changes in classification it considers necessary to the Legislature. [PL 2021, c. 551, §3 (AMD).]
D. The Legislature shall have sole authority to make any changes in the classification of the waters of the State. [PL 1985, c. 698, §15 (NEW).]
[PL 2021, c. 551, §3 (AMD).]
2-A. Removal of designated uses; creation of subcategories of designated uses. Removal of designated uses and creation of subcategories of designated uses are governed by the provisions of this subsection and 40 Code of Federal Regulations, Part 131, as amended.
A. The board must conduct a use attainability analysis:
(1) Prior to proposing to the Legislature a designated use of a specific water body that does not include the uses specified in the Federal Water Pollution Control Act, Public Law 92-500, Section 101(a)(2), as amended; or
(2) Prior to proposing to the Legislature the removal of a designated use or the adoption of a subcategory of such a designated use that requires less stringent criteria. [PL 1993, c. 344, §1 (NEW).]
B. The board may not recommend to the Legislature the removal of a designated use or the establishment of a subcategory of the use, if:
(1) It is an existing use as defined in section 464, subsection 4, paragraph F, subparagraph (1), unless another designated use is adopted requiring more stringent criteria;
(2) The use can be attained by implementing effluent limits required under the Federal Water Pollution Control Act, Public Law 92-500, Sections 301(b) and 306, as amended and by implementing cost-effective and reasonable best management practices for nonpoint source control;
(3) The water body in question is currently attaining the designated use; or
(4) Adoption of the recommendation allows the introduction of a new discharge or the expansion of an existing discharge into the water body in question that is not attaining the designated use. [PL 1993, c. 344, §1 (NEW).]
C. The board may adopt any recommendation under this subsection only after holding a public hearing in the affected area or adjacent to the affected area. Conduct of the public hearing and the board's subsequent decision are governed by Title 5, chapter 375, subchapter IV. [PL 1993, c. 344, §1 (NEW).]
D. A finding by the board that attainment of a designated use is not feasible must be supported by a demonstration that the conditions of 40 Code of Federal Regulations 131.10(g) are met. [PL 1993, c. 344, §1 (NEW).]
E. If the board adopts a proposal to enact a designated use under paragraph A, subparagraph (1) or to remove a designated use or adopt a subcategory of a designated use under paragraph A, subparagraph (2), it shall submit to the joint standing committee of the Legislature having jurisdiction over environment and natural resources matters during the next regular session of the Legislature a report that includes that recommendation and the joint standing committee may report out legislation to implement that recommendation. The board may not propose any other recommendation to the Legislature under this subsection. The Legislature has sole authority to make changes in the designated uses of the waters of the State, including the creation of a subcategory of a designated use. [PL 2021, c. 551, §4 (AMD).]
F. For the purposes of this subsection, "designated use" means the use specified in water quality standards for each water body or segment under sections 465 to 465‑C and sections 467 to 470 whether or not that use is being attained. A designated use includes its associated habitat characteristic under sections 465 to 465‑C. [PL 1993, c. 344, §1 (NEW).]
[PL 2021, c. 551, §4 (AMD).]
2-B. Temporary removal of designated uses; use attainability analysis and creation of subcategory of uses for combined sewer overflows. When designated uses are not being met as a result of combined sewer overflow discharges, the board may, consistent with this subsection and 40 Code of Federal Regulations, Part 131, temporarily remove designated uses that are not existing uses and create a temporary combined sewer overflow subcategory referred to as a CSO subcategory. Notwithstanding this subsection, it remains the goal of the State to fully maintain and restore water quality and eliminate or control combined sewer overflows as soon as practicable.
A. The board may create temporary CSO subcategories in classes B, C and SB and SC waters only when, due to the age, condition and design of an existing sewer system, technical or financial limitations prevent the timely attainment of all designated uses. In a CSO subcategory, uses are suspended only in the smallest area possible, for the shortest duration practicable and include only those designated uses and areas determined by the board to have the least potential for public benefit. [PL 1995, c. 284, §1 (NEW).]
B. Notwithstanding subsections 2 and 2‑A, CSO subcategories may be created by the board upon application by a municipality or quasi-municipality having licensed combined sewer overflow discharges, if the following standards are met.
(1) The applicant submits to the department for approval, with or without conditions, a study and plan, including an implementation schedule, for combined sewer overflow abatement, referred to as the CSO plan. In order for the board to create a CSO subcategory, the CSO plan must:
(a) Place high priority on abatement of combined sewer overflows that affect waters having the greatest potential for public use or benefit and plan to relocate any remaining discharges to areas where minimal impacts or losses of uses would occur; and
(b) Provide for the implementation as soon as practical of technology-based control methods to achieve best practicable treatment or ensure that cost-effective best management practices are being implemented.
(2) The board finds that attainment of a designated use is not feasible and such determination must be supported by demonstration that the conditions of 40 Code of Federal Regulations, Part 131.10(g) are met.
(3) The board finds that the uses to be affected are not existing uses as defined in subsection 4, paragraph F, subparagraph (1).
(4) The board finds that discharges from combined sewer overflows are not affecting uses that, in the board's judgment, constitute high value or important resources. In determining if a resource is high value or important the board shall consider its economic, recreational and ecological significance, the likelihood that removal of a combined sewer overflow will lead to utilization of that resource and the effects of other discharges or conditions on that resource. [PL 1995, c. 284, §1 (NEW).]
C. Prior to creating any CSO subcategory, the board shall adopt rules regarding required studies, best practicable treatment, abatement options and related issues for combined sewer overflows. CSO subcategories may be created only after completion of the following.
(1) Either during or following development of combined sewer abatement plans, licensees shall conduct public hearings in the area that would be affected by a CSO subcategory. Notices and records of hearings must be kept and included as part of an application made to the board.
(2) Combined sewer overflow abatement plans must be submitted to the department for technical review and approval.
(3) Licensees proposing CSO subcategories shall submit formal applications to the board. Information in the application must include: description of the areas and uses to be affected, the time and duration of effects, comments received at public hearings, a description of continuing efforts to abate impacts and proposals for periodic review and update of abatement plans.
(4) The board shall provide public notice of applications for CSO subcategories and solicit public comments. The board shall also consult with agencies, public officials and other persons identified as having interest in the area to be affected. Based on the results of public hearings held by the applicant, the comments received and the nature of the application, the board may hold a public hearing.
(5) The board may approve, approve with conditions or deny applications for CSO subcategories. In cases when a water body is affected by combined sewer overflows from more than one licensee, the board shall, to the maximum extent possible, consider regional impacts and seek to establish common goals and uses for those waters.
(6) In a manner prescribed by the board, applicants receiving approval of CSO subcategories shall provide notice to the public in the area affected, describing the limitations on use of the water body. [PL 1995, c. 284, §1 (NEW).]
D. Upon creation of a CSO subcategory and removal of a designated use, the board may temporarily suspend or modify water quality criteria associated with that use as appropriate, but only to the extent and duration that those criteria are affected by the licensee for whom the assignment is made. Action by the board under this subsection does not relieve other discharge sources from any requirement to provide necessary treatment or best management practices or to comply with water quality criteria. [PL 1995, c. 284, §1 (NEW).]
E. Either independently or in conjunction with the requirements of subsection 3 and upon renewal of individual waste discharge licenses, the department shall periodically review all CSO subcategories. Reviews of CSO subcategories must take into consideration water quality criteria and uses, combined sewer overflow abatement technology, monitoring data, financial information and regulatory requirements affecting CSO subcategories. [PL 1995, c. 284, §1 (NEW).]
Upon petition by the department or any person or on its own motion, the board may, at its discretion, and following notice and opportunity for hearing, revise or revoke a CSO subcategory when it finds any change in the conditions under which the existing designation was made. The failure to comply with the measures specified in an approved combined sewer overflow abatement plan is cause for revocation of a CSO subcategory.
[PL 1995, c. 284, §1 (NEW).]
3. Reports to the Legislature. The commissioner or the board, as applicable, shall periodically report to the Legislature as follows.
A. During the first regular session of each Legislature, the commissioner shall submit to the joint standing committee of the Legislature having jurisdiction over environment and natural resources matters a report on the quality of the State's waters that describes existing water quality, identifies waters that are not attaining their classification and states what measures are necessary for the attainment of the standards of their classification. [PL 2021, c. 551, §5 (AMD).]
B. The board shall, from time to time, but at least once every 3 years, hold public hearings for the purpose of reviewing the water quality classification system and related standards and, as appropriate, recommending changes in the standards. After conducting the review, the board shall submit to the joint standing committee of the Legislature having jurisdiction over environment and natural resources matters a report describing the board's findings and any recommendations for changes to the water quality classification system and related standards and the joint standing committee may report out legislation to implement those recommendations. [PL 2021, c. 551, §5 (AMD).]
C. During the first regular session of each Legislature, the commissioner shall submit to the joint standing committee of the Legislature having jurisdiction over environment and natural resources matters a report on the status of licensed discharges. [PL 2021, c. 551, §5 (AMD).]
D. [PL 1989, c. 890, Pt. A, §40 (AFF); PL 1989, c. 890, Pt. B, §55 (RP).]
[PL 2021, c. 551, §5 (AMD).]
4. General provisions. The classification system for surface waters established by this article shall be subject to the following provisions.
A. Notwithstanding section 414‑A, the department may not issue a water discharge license for any of the following discharges:
(1) Direct discharge of pollutants to waters having a drainage area of less than 10 square miles, except that:
(a) Discharges into these waters that were licensed prior to January 1, 1986 are allowed to continue only until practical alternatives exist;
(b) Storm water discharges in compliance with state and local requirements are exempt from this subparagraph;
(c) Aquatic pesticide or chemical discharges approved by the department and conducted by the department, the Department of Inland Fisheries and Wildlife or an agent of either agency for the purpose of restoring biological communities affected by an invasive species are exempt from this subparagraph;
(d) Chemical discharges for the purpose of restoring water quality in GPA waters approved by the department are exempt from this subparagraph;
(e) Discharges of aquatic pesticides approved by the department for the control of mosquito-borne diseases in the interest of public health and safety using materials and methods that provide for protection of nontarget species are exempt from this subparagraph. When the department issues a license for the discharge of aquatic pesticides authorized under this division, the department shall notify the municipality in which the application is licensed to occur and post the notice on the department's publicly accessible website; and
(f) Discharges of pesticides approved by the department are exempt from this subparagraph that are:
(i) Unintended and an incidental result of the spraying of pesticides;
(ii) Applied in compliance with federal labeling restrictions; and
(iii) Applied in compliance with statute, Board of Pesticides Control rules and best management practices;
(2) New direct discharge of domestic pollutants to tributaries of Class-GPA waters;
(3) Any discharge into a tributary of GPA waters that by itself or in combination with other activities causes water quality degradation that would impair the characteristics and designated uses of downstream GPA waters or causes an increase in the trophic state of those GPA waters;
(4) Discharge of pollutants to waters of the State that imparts color, taste, turbidity, toxicity, radioactivity or other properties that cause those waters to be unsuitable for the designated uses and characteristics ascribed to their class;
(5) Discharge of pollutants to any water of the State that violates sections 465, 465‑A and 465‑B, except as provided in section 451; causes the pH of fresh waters to fall outside of the 6.5 to 9.0 range; or causes the pH of estuarine and marine waters to fall outside of the 7.0 to 8.5 range;
(6) New discharges of domestic pollutants to the surface waters of the State that are not conveyed and treated in municipal or quasi-municipal sewage facilities. For the purposes of this subparagraph, "new discharge" means any overboard discharge that was not licensed as of June 1, 1987, except discharges from vessels and those discharges that were in continuous existence for the 12 months preceding June 1, 1987, as demonstrated by the applicant to the department with clear and convincing evidence. The volume of the discharge from an overboard discharge facility that was licensed as of June 1, 1987 is determined by the actual or estimated volume from the facilities connected to the overboard discharge facility during the 12 months preceding June 1, 1987 or the volume allowed by the previous license, whichever is less, unless it is found by the department that an error was made during prior licensing. The months during which a discharge may occur from an overboard discharge facility that was licensed as of June 1, 1987 must be determined by the actual use of the facility at the time of the most recent license application prior to June 1, 1987 or the actual use of the facility during the 12 months prior to June 1, 1987, whichever is greater. If the overboard discharge facility was the primary residence of an owner at the time of the most recent license application prior to June 1, 1987 or during the 12 months prior to June 1, 1987, then the facility is considered a year-round residence. "Year-round residence" means a facility that is continuously used for more than 8 months of the year. For purposes of licensing, the department shall treat an increase in the licensed volume or quantity of an existing discharge or an expansion in the months during which the discharge takes place as a new discharge of domestic pollutants;
(7) After the Administrator of the United States Environmental Protection Agency ceases issuing permits for discharges of pollutants to waters of this State pursuant to the administrator's authority under the Federal Water Pollution Control Act, Section 402(c)(1), any proposed license to which the administrator has formally objected under 40 Code of Federal Regulations, Section 123.44, as amended, or any license that would not provide for compliance with applicable requirements of that Act or regulations adopted thereunder;
(8) Discharges for which the imposition of conditions can not ensure compliance with applicable water quality requirements of this State or another state;
(9) Discharges that would, in the judgment of the Secretary of the United States Army, substantially impair anchorage or navigation;
(10) Discharges that would be inconsistent with a plan or plan amendment approved under the Federal Water Pollution Control Act, Section 208(b); and
(11) Discharges that would cause unreasonable degradation of marine waters or when insufficient information exists to make a reasonable judgment whether the discharge would cause unreasonable degradation of marine waters.
Notwithstanding subparagraph (6), the department may issue a wastewater discharge license allowing for an increase in the volume or quantity of discharges of domestic pollutants from any university, college or school administrative unit sewage facility, as long as the university, college or school administrative unit has a wastewater discharge license valid on the effective date of this paragraph and the increase in discharges does not violate the conditions of subparagraphs (1) to (5) and (7) to (11) or other applicable laws. [PL 2021, c. 551, §6 (AMD).]
B. All surface waters of the State shall be free of settled substances which alter the physical or chemical nature of bottom material and of floating substances, except as naturally occur, which impair the characteristics and designated uses ascribed to their class. [PL 1985, c. 698, §15 (NEW).]
C. Where natural conditions, including, but not limited to, marshes, bogs and abnormal concentrations of wildlife cause the dissolved oxygen or other water quality criteria to fall below the minimum standards specified in sections 465, 465‑A and 465‑B, those waters shall not be considered to be failing to attain their classification because of those natural conditions. [PL 1985, c. 698, §15 (NEW).]
D. Except as otherwise provided in this paragraph, for the purpose of computing whether a discharge will violate the classification of any river or stream, the assimilative capacity of the river or stream must be computed using the minimum 7-day low flow that can be expected to occur with a frequency of once in 10 years. The department may use a different flow rate only for those toxic substances regulated under section 420 and for those nutrients specified in department rules. To use a different flow rate, the department must find that the flow rate is consistent with the risk being addressed. [PL 2017, c. 319, §3 (AMD).]
E. The waters contained in excavations approved by the department for wastewater treatment purposes are unclassified waters. [PL 1989, c. 890, Pt. A, §40 (AFF); PL 1989, c. 890, Pt. B, §57 (AMD).]
F. The antidegradation policy of the State is governed by the following provisions.
(1) Existing in-stream water uses and the level of water quality necessary to protect those existing uses must be maintained and protected. Existing in-stream water uses are those uses which have actually occurred on or after November 28, 1975, in or on a water body whether or not the uses are included in the standard for classification of the particular water body.
Determinations of what constitutes an existing in-stream water use on a particular water body must be made on a case-by-case basis by the department. In making its determination of uses to be protected and maintained, the department shall consider designated uses for that water body and:
(a) Aquatic, estuarine and marine life present in the water body;
(b) Wildlife that utilize the water body;
(c) Habitat, including significant wetlands, within a water body supporting existing populations of wildlife or aquatic, estuarine or marine life, or plant life that is maintained by the water body;
(d) The use of the water body for recreation in or on the water, fishing, water supply, or commercial activity that depends directly on the preservation of an existing level of water quality. Use of the water body to receive or transport waste water discharges is not considered an existing use for purposes of this antidegradation policy; and
(e) Any other evidence that, for divisions (a), (b) and (c), demonstrates their ecological significance because of their role or importance in the functioning of the ecosystem or their rarity and, for division (d), demonstrates its historical or social significance.
(1-A) The department may only issue a waste discharge license pursuant to section 414‑A, or approve a water quality certification pursuant to the United States Clean Water Act, Section 401, Public Law 92-500, as amended, when the department finds that:
(a) The existing in-stream use involves use of the water body by a population of plant life, wildlife, or aquatic, estuarine or marine life, or as aquatic, estuarine, marine, wildlife, or plant habitat, and the applicant has demonstrated that the proposed activity would not have a significant impact on the existing use. For purpose of this division, significant impact means:
(i) Impairing the viability of the existing population, including significant impairment to growth and reproduction or an alteration of the habitat which impairs viability of the existing population; or
(b) The existing in-stream use involves use of the water body for recreation in or on the water, fishing, water supply or commercial enterprises that depend directly on the preservation of an existing level of water quality and the applicant has demonstrated that the proposed activity would not result in significant degradation of the existing use.
The department shall determine what constitutes a population of a particular species based upon the degree of geographic and reproductive isolation from other individuals of the same species.
If the department fails to find that the conditions of this subparagraph are met, water quality certification, pursuant to the United States Clean Water Act, Section 401, Public Law 92-500, as amended, is denied.
(2) (CONFLICT: Text as amended by PL 2021, c. 503, §1) Where high quality waters of the State constitute an outstanding national resource, that water quality must be maintained and protected. For purposes of this paragraph, the following waters are considered outstanding national resources: those water bodies in national and state parks and wildlife refuges; public reserved lands; and those water bodies classified as Class AA and SA waters pursuant to section 465, subsection 1; section 465‑B, subsection 1; and, unless otherwise specified, listed under sections 467, 468 and 469.
(2) (CONFLICT: Text as amended by PL 2021, c. 551, §7) Where high quality waters of the State constitute an outstanding national resource, that water quality must be maintained and protected. For purposes of this paragraph, the following waters are considered outstanding national resources: those water bodies in national and state parks and wildlife refuges and in the Katahdin Woods and Waters National Monument; those water bodies in public reserved lands; and those water bodies classified as Class AA and SA waters pursuant to section 465, subsection 1; section 465‑B, subsection 1; and listed under sections 467, 468 and 469.
(3) The department may only issue a discharge license pursuant to section 414‑A or approve water quality certification pursuant to the Federal Water Pollution Control Act, Section 401, Public Law 92-500, as amended, if the standards of classification of the water body and the requirements of this paragraph are met. The department may issue a discharge license or approve water quality certification for a project affecting a water body in which the standards of classification are not met if the project does not cause or contribute to the failure of the water body to meet the standards of classification.
(4) When the actual quality of any classified water exceeds the minimum standards of the next highest classification, that higher water quality must be maintained and protected. Pursuant to subsection 3, paragraph B, the board shall recommend to the Legislature that that water be reclassified in the next higher classification.
(5) The department may only issue a discharge license pursuant to section 414‑A or approve water quality certification pursuant to the United States Clean Water Act, Section 401, Public Law 92-500, as amended, which would result in lowering the existing quality of any water body after making a finding, following opportunity for public participation, that the action is necessary to achieve important economic or social benefits to the State and when the action is in conformance with subparagraph (3). That finding must be made following procedures established by rule of the board. [PL 2021, c. 503, §1 (AMD); PL 2021, c. 551, §§7, 8 (AMD).]
G. [PL 1989, c. 442, §5 (RP).]
H. A hydropower project, as defined by section 632, constructed after the effective date of this paragraph may cause some change to the habitat and aquatic life of the project's impoundment and the waters immediately downstream of and measurably affected by the project, so long as the habitat and aquatic life criteria of those waters' classification under sections 465, 465‑A, 467, and 468 are met. This paragraph does not constitute any change in the criteria for habitat and aquatic life under sections 465 and 465‑A. [PL 1991, c. 813, Pt. D, §1 (NEW).]
I. [PL 1995, c. 312, §1 (NEW); MRSA T. 38 §464, sub-§4, ¶ I (RP).]
J. For the purpose of calculating waste discharge license limits for toxic substances, the department may use any unallocated assimilative capacity that the department has set aside for future growth if the use of that unallocated assimilative capacity would avoid an exceedance of applicable ambient water quality criteria or a determination by the department of a reasonable potential to exceed applicable ambient water quality criteria. [PL 2011, c. 194, §3 (NEW).]
K. Unless otherwise required by an applicable effluent limitation guideline adopted by the department, any limitations for metals in a waste discharge license may be expressed only as mass-based limits. [PL 2011, c. 194, §3 (NEW).]
[PL 2021, c. 503, §1 (AMD); PL 2021, c. 551, §§6-8 (AMD).]
5. Rulemaking. In accordance with the Maine Administrative Procedure Act, the board shall promulgate rules necessary to implement the water quality classification system established by this article. In promulgating rules, the board shall solicit and consider, in addition to any other materials, information on the economic and environmental impact of those rules.
Rules shall be promulgated by January 1, 1987, and as necessary thereafter, and shall include, but are not limited to, sampling and analytical methods, protocols and procedures for satisfying the water quality criteria, including evaluation of the impact of any discharge on the resident biological community.
Rules adopted pursuant to this subsection shall become effective upon adoption. Rules adopted pursuant to this subsection shall be submitted to the joint standing committee of the Legislature having jurisdiction over natural resources for review during the next regular session of the Legislature following adoption. This committee may submit legislation it deems necessary to clarify legislative intent regarding rules adopted pursuant to this subsection. If the committee takes no action, the rules shall continue in effect.
[PL 1985, c. 698, §15 (NEW).]
6. Implementation of biological water quality criteria. The implementation of water quality criteria pertaining to the protection of the resident biological community shall be governed by the provisions of this subsection.
A. At any time during the term of a valid wastewater discharge license that was issued prior to the effective date of this article, the board may modify that license in accordance with section 341‑D, subsection 3 if the discharger is not in compliance with the water quality criteria pertaining to the protection of the resident biological community. When a discharge license is modified under this subsection, the board shall establish a reasonable schedule to bring the discharge into compliance with the water quality criteria pertaining to the protection of the resident biological community. [PL 1991, c. 66, Pt. A, §13 (RPR); PL 1991, c. 66, Pt. A, §43 (AFF).]
B. When a discharge license is issued after the effective date of this article and before the effective date of the rules adopted pursuant to subsection 5, the department shall establish a reasonable schedule to bring the discharge into compliance with the water quality criteria pertaining to the protection of the resident biological community. [PL 1989, c. 890, Pt. A, §40 (AFF); PL 1989, c. 890, Pt. B, §59 (AMD).]
C. A discharger seeking a new discharge license following the effective date of the rules adopted under subsection 5 shall comply with the water quality criteria of this article. [PL 1985, c. 698, §15 (NEW).]
[PL 1991, c. 66, Pt. A, §13 (AMD); PL 1991, c. 66, Pt. A, §43 (AFF).]
7. Interdepartmental coordination. The commissioner, the Commissioner of Marine Resources and the Commissioner of Health and Human Services shall jointly:
A. Make available accurate and consistent information on the requirements of this section, section 411‑A and section 414‑A, subsection 1‑B; and [PL 1989, c. 442, §6 (NEW).]
B. Certify wastewater treatment and disposal technologies which can be used to replace overboard discharges. [PL 1989, c. 890, Pt. A, §40 (AFF); PL 1989, c. 890, Pt. B, §60 (AMD).]
[PL 1989, c. 890, Pt. A, §40 (AFF); PL 1989, c. 890, Pt. B, §60 (AMD); PL 2003, c. 689, Pt. B, §7 (REV).]
8. Development of group systems. Subject to the provisions of section 414‑A, subsection 1‑B, the commissioner shall coordinate the development and implementation of wastewater treatment and disposal systems serving more than one residence or commercial establishment when individual replacement systems are not feasible.
[PL 1989, c. 890, Pt. A, §40 (AFF); PL 1989, c. 890, Pt. B, §60 (AMD).]
9. Existing hydropower impoundments managed as great ponds; habitat and aquatic life criteria.
[PL 2005, c. 159, §1 (RP).]
9-A. Existing hydropower impoundments managed as great ponds; habitat and aquatic life criteria. The following provisions govern habitat and aquatic life criteria for existing hydropower impoundments managed as great ponds.
A. For the purposes of water quality certification under the Federal Water Pollution Control Act, Public Law 92-500, Section 401, as amended, and licensing of modifications under section 636, the hydropower project located on the water body referenced in section 467, subsection 7, paragraph C, subparagraph (1), division (b-1), is deemed to have met the habitat characteristics and aquatic life criteria in the existing impoundment if:
(1) The project is in existence on June 30, 1992;
(2) The project creates an impoundment that remains classified under section 465‑A after June 30, 1992;
(3) The project creates an impoundment that is subject to water level fluctuations that have an effect on the habitat and aquatic life in the littoral zone so that the habitat and aquatic life differ significantly from that found in an unimpounded great pond; and
(4) The existing impounded waters are able to support all species of fish indigenous to those waters and the structure and function of the resident biological community in the impounded waters is maintained. [PL 2005, c. 159, §2 (NEW).]
B. For the purposes of water quality certification under the Federal Water Pollution Control Act, Public Law 92-500, Section 401, as amended, and licensing of modifications under section 636, Ragged Lake, located in the Penobscot River, West Branch drainage, is deemed to have met the habitat characteristics and aquatic life criteria in the existing impoundment if that habitat and aquatic life satisfy the aquatic life criteria contained in section 465, subsection 4, paragraph C, except that habitat and aquatic life in the portions of the water body affected by annual drawdowns of up to 20 feet may reflect the effects of such drawdowns, based on a use attainability analysis conducted by the board pursuant to subsection 2‑A. [PL 2005, c. 159, §2 (NEW).]
C. For the purposes of water quality certification under the Federal Water Pollution Control Act, Public Law 92-500, Section 401, as amended, and licensing of modifications under section 636, Seboomook Lake, located in the Penobscot River, West Branch drainage, is deemed to have met the habitat characteristics and aquatic life criteria in the existing impoundment if that habitat and aquatic life satisfy the aquatic life criteria contained in section 465, subsection 4, paragraph C, except that habitat and aquatic life in the portions of the water body affected by annual drawdowns of up to 17 feet may reflect the effects of such drawdowns, based on a use attainability analysis conducted by the board pursuant to subsection 2‑A. [PL 2005, c. 159, §2 (NEW).]
D. Other than those described in paragraphs A, B and C, all hydropower projects with impoundments in existence on June 30, 1992 that remain classified under section 465‑A after June 30, 1992 and that do not attain the habitat and aquatic life criteria of that section must, at a minimum, satisfy the aquatic life criteria contained in section 465, subsection 4, paragraph C. [PL 2005, c. 159, §2 (NEW).]
E. When the actual water quality of the impounded waters attains any more stringent characteristic or criteria of those waters' classification under section 465‑A, that water quality must be maintained and protected. [PL 2005, c. 159, §2 (NEW).]
[PL 2005, c. 159, §2 (NEW).]
10. Existing hydropower impoundments managed under riverine classifications; habitat and aquatic life criteria. For the purposes of water quality certification under the Federal Water Pollution Control Act, Public Law 92-500, Section 401, as amended, and the licensing of modifications under section 636, hydropower projects in existence on the effective date of this subsection, the impoundments of which are classified under section 465, are subject to the provisions of this subsection in recognition of some changes to aquatic life and habitat that have occurred due to the existing impoundments of these projects.
A. Except as provided in paragraphs B and D, the habitat characteristics and aquatic life criteria of Classes A and B are deemed to be met in the existing impoundments classified A or B of those projects if:
(1) The impounded waters achieve the aquatic life criteria of section 465, subsection 4, paragraph C. [PL 1991, c. 813, Pt. B, §1 (NEW).]
B. The habitat characteristics and aquatic life criteria of Classes A and B are not deemed to be met in the existing impoundments of those projects referred to in paragraph A if:
(1) Reasonable changes can be implemented that do not significantly affect existing energy generation capability; and
(2) Those changes would result in improvement in the habitat and aquatic life of the impounded waters.
If the conditions described in subparagraphs (1) and (2) occur, those changes must be implemented and the resulting improvement in habitat and aquatic life must be achieved and maintained. [PL 1991, c. 813, Pt. B, §1 (NEW).]
C. If the conditions described in paragraph B, subparagraphs (1) and (2) occur at a project in existence on the effective date of this subsection, the impoundment of which is classified C, the changes described in paragraph B, subparagraphs (1) and (2) must be implemented and the resulting improvement in habitat and aquatic life must be achieved and maintained. [PL 1991, c. 813, Pt. B, §1 (NEW).]
D. When the actual water quality of waters affected by this subsection attains any more stringent characteristic or criteria of those waters' classification under sections 465, 467 and 468, that water quality must be maintained and protected. [PL 1991, c. 813, Pt. B, §1 (NEW).]
[RR 2021, c. 2, Pt. A, §130 (COR).]
11. Downstream stretches affected by existing hydropower projects. Hydropower projects in existence on the effective date of this subsection that are located on water bodies referenced in section 467, subsection 4, paragraph A, subparagraphs (1) and (7), and section 467, subsection 12, paragraph A, subparagraphs (7) and (9) are subject to the provisions of this subsection.
For the purposes of water quality certification of hydropower projects under the Federal Water Pollution Control Act, Public Law 92-500, Section 401, as amended, and licensing of modifications to these hydropower projects under section 636, the habitat characteristics and aquatic life criteria of Class A are deemed to be met in the waters immediately downstream of and measurably affected by the projects listed in this subsection if the criteria contained in section 465, subsection 4, paragraph C are met.
[RR 1993, c. 1, §114 (COR).]
12. Discharges from certain fish hatcheries. An unlicensed discharge from a fish hatchery is considered, and continues to be considered after it is licensed pursuant to section 413, the same as a discharge licensed prior to January 1, 1986 for the purposes of subsection 4, paragraph A, subparagraph (1); section 465, subsection 2, paragraph C; and section 465‑A, subsection 1, paragraph C if the following conditions are met:
A. The discharge was in existence prior to January 1, 1986; [PL 1999, c. 720, §1 (NEW).]
B. The fish hatchery is licensed to cultivate fish by the Department of Inland Fisheries and Wildlife on the effective date of this subsection; and [PL 1999, c. 720, §1 (NEW).]
C. An application from the hatchery for a waste discharge license is accepted as complete for processing by the Department of Environmental Protection within 90 days of notification that a waste discharge license is required pursuant to section 413. [PL 1999, c. 720, §1 (NEW).]
The Department of Environmental Protection shall notify a fish hatchery with an unlicensed discharge that a waste discharge license is required pursuant to section 413 within 90 days of the effective date of this subsection or within 90 days of finding the unlicensed discharge.
[PL 1999, c. 720, §1 (NEW).]
13. Measurement of dissolved oxygen in riverine impoundments. Compliance with dissolved oxygen criteria in existing riverine impoundments must be measured as follows.
A. Compliance with dissolved oxygen criteria may not be measured within 0.5 meters of the bottom of existing riverine impoundments. [PL 2003, c. 257, §1 (NEW).]
B. Where mixing is inhibited due to thermal stratification in an existing riverine impoundment, compliance with numeric dissolved oxygen criteria may not be measured below the higher of:
(1) The point of thermal stratification when such stratification occurs; or
(2) The point proposed by the department as an alternative depth for a specific riverine impoundment based on all factors included in section 466, subsection 11‑A and for which a use attainability analysis is conducted if required by the United States Environmental Protection Agency.
For purposes of this paragraph, "thermal stratification" means a change of temperature of at least one degree Celsius per meter of depth, causing water below this point in an impoundment to become isolated and not mix with water above this point in the impoundment. [PL 2003, c. 257, §1 (NEW).]
C. Where mixing is inhibited due to natural topographical features in an existing riverine impoundment, compliance with numeric dissolved oxygen criteria may not be measured within that portion of the impoundment that is topographically isolated. Such natural topographic features may include, but not be limited to, natural deep holes or river bottom sills. [PL 2003, c. 257, §1 (NEW).]
Notwithstanding the provisions of this subsection, dissolved oxygen concentrations in existing riverine impoundments must be sufficient to support existing and designated uses of these waters. For purposes of this subsection, "existing riverine impoundments" means all impoundments of rivers and streams in existence as of January 1, 2001 and not otherwise classified as GPA.
[PL 2003, c. 257, §1 (NEW).]
SECTION HISTORY
PL 1985, c. 698, §15 (NEW). PL 1987, c. 180, §§4,5 (AMD). PL 1987, c. 419, §10 (AMD). PL 1987, c. 567 (AMD). PL 1989, c. 309, §2 (AMD). PL 1989, c. 442, §§4-6 (AMD). PL 1989, c. 764, §1 (AMD). PL 1989, c. 856, §§6,7 (AMD). PL 1989, c. 878, §B40 (AMD). PL 1989, c. 890, §§A40,B54-60 (AMD). PL 1991, c. 66, §§A12,13,B1 (AMD). PL 1991, c. 66, §A43 (AFF). PL 1991, c. 159 (AMD). PL 1991, c. 813, §§A1,B1,C1, D1 (AMD). RR 1993, c. 1, §§113,114 (COR). PL 1993, c. 40, §1 (AMD). PL 1993, c. 344, §§1,2 (AMD). PL 1995, c. 284, §1 (AMD). PL 1995, c. 312, §1 (AMD). PL 1997, c. 794, §A30 (AMD). PL 1999, c. 720, §1 (AMD). PL 2003, c. 245, §7 (AMD). PL 2003, c. 246, §14 (AMD). PL 2003, c. 257, §1 (AMD). PL 2003, c. 318, §2 (AMD). PL 2003, c. 551, §6 (AMD). PL 2003, c. 650, §3 (AMD). PL 2003, c. 689, §B7 (REV). PL 2005, c. 159, §§1,2 (AMD). PL 2005, c. 182, §1 (AMD). PL 2007, c. 291, §1 (AMD). PL 2011, c. 194, §3 (AMD). PL 2013, c. 193, §1 (AMD). PL 2015, c. 124, §6 (AMD). PL 2017, c. 319, §§2, 3 (AMD). PL 2021, c. 503, §1 (AMD). PL 2021, c. 551, §§3-8 (AMD). RR 2021, c. 2, Pt. A, §130 (COR).