7 Del. Admin. Code § 7401-5.0

Current through Reigster Vol. 28, No. 6, December 1, 2024

Section 7401-5.0 - Antidegradation and ERES Waters Policies

5.1 Existing instream water uses and the level of water quality necessary to protect the existing uses shall be maintained and protected. Degradation of water quality in such a manner that results in reduced number, quality, or river or stream mileage of existing uses shall be prohibited. Degradation shall be defined for the purposes of this section as a statistically significant reduction, accounting for natural variations, in biological, chemical, or habitat quality as measured or predicted using appropriate assessment protocols.

5.2 Where the quality of the waters exceeds levels necessary to support propagation of fish, shellfish, and wildlife and recreation in and on the water, that quality shall be maintained and protected. In the case of waters of exceptional recreational or ecological significance, existing quality shall be maintained or enhanced. Limited degradation may be allowed if the Department finds, after full satisfaction of public participation provisions of 7 Del.C. Sections 6004 and 6006 and the intergovernmental coordination provisions of the State's continuing planning process as required in 40 CFR Part 130, that allowing lower water quality is necessary to accommodate important social or economic development, or would result in a substantial net environmental or public health benefit, in the area in which the waters are located. In allowing such degradation or lower water quality, the Department shall assure maintenance of water quality adequate for full protection of existing uses. Further, the Department shall assure that there shall be achieved the highest statutory and regulatory requirements for all new and existing point sources and all cost-effective and reasonable best management practices for nonpoint source control.

5.3 Where high quality waters constitute an outstanding National resource, such as waters of National parks and wildlife refuges, existing quality shall be maintained and protected.

5.4 In those cases where potential water quality impairment associated with a thermal discharge is involved, the antidegradation policy and implementing method shall be consistent with Section 316 of the Water Quality Act of 1987.

5.5 The hearing requirement imposed by subsection 5.2 above shall not be construed to impose a requirement for an additional public hearing where such a hearing is otherwise held pursuant to law, provided the requirements of this section are hereby met.

5.6 Criteria for Waters of Exceptional Recreational or Ecological Significance (ERES Waters)

5.6.1 General Policy

5.6.1.1 Designated ERES waters shall be accorded a level of protection and monitoring in excess of that provided most other waters of the State. These waters are recognized as special natural assets of the State, and must be protected and enhanced for the benefit of present and future generations of Delawareans.

5.6.1.2 ERES waters shall be restored, to the maximum extent practicable, to their natural condition. To this end, the Department shall, through adoption of a pollution control strategy for each ERES stream basin, take appropriate action to cause the systematic control, reduction, or removal of existing pollution sources, and the diversion of new pollution sources, away from ERES waters.

5.6.1.3 Discharges to ERES waters shall be avoided to the maximum extent practicable. In order to be permitted, a discharge must be the least environmentally damaging practicable alternative.

5.6.1.4 Prior to any public notice for a discharge permit required pursuant to 7 Del.C. Ch. 60, the Department shall make a determination that potential impacts have been avoided to the maximum extent practicable, and that remaining unavoidable impacts will be minimized to the extent appropriate and practicable. Findings shall be based upon appropriate factual determinations, evaluations, and tests with special emphasis on the persistence and permanence of the impacts. Under this provision impacts considered individually or collectively include:

5.6.1.4.1 Impacts of pollutants on human health and welfare;

5.6.1.4.2 Impacts of pollutants on life stages of aquatic life and other wildlife dependent on aquatic ecosystems including, but not limited to, the transfer, concentration, and spread of pollutants or their by-products through biological, physical, and chemical processes;

5.6.1.4.3 Impacts of pollutants on aquatic ecosystem diversity, productivity, and stability. Such impacts may include, but are not limited to, loss of fish and wildlife habitat or loss of the capacity of a wetland to assimilate nutrients, purify water, or reduce wave energy; or

5.6.1.4.4 Impacts on recreational, aesthetic, and economic values.

5.6.1.5 Any applicant for a discharge permit required pursuant to 7 Del.C. Ch. 60 shall provide to the Department, as part of a complete application, a resource assessment tailored to the site performed by qualified professionals. Such assessments shall fully consider ecological functions and values in light of the policies set forth in these standards. Consideration shall be given to:

5.6.1.5.1 Potential impacts on physical and chemical characteristics of the aquatic ecosystems which shall include, but not be limited to, substrates, substrate particulates/turbidity, water, current patterns, water circulation, normal water fluctuations, and salinity gradients;

5.6.1.5.2 Potential impacts on biological characteristics of the aquatic ecosystem which shall include, but not be limited to, fish, crustaceans, mollusks and other organisms in the food web, other wildlife, and threatened or endangered species; and

5.6.1.5.3 Potential effects on human use characteristics which shall include, but not be limited to, water supplies, recreational and commercial fisheries, water related recreation, aesthetics, parks, research sites, wildlife areas or public access areas.

5.6.2 General Provisions

5.6.2.1 In cases where natural conditions prevent attainment of applicable fresh or marine dissolved oxygen criteria, reduction in dissolved oxygen levels as a result of human activities shall be prohibited.

5.6.2.2 All point, and human induced nonpoint sources subject to control through use of best management practices or otherwise, shall be required to remove nutrients to the extent necessary to prevent excessive growth of photosynthetic organisms.

5.6.2.3 All point, and human induced nonpoint sources subject to control through use of best management practices or otherwise, shall be required to remove particulate matter to the extent necessary to minimize turbidity.

5.6.2.4 ERES waters shall not exhibit toxicity within aquatic habitats commonly used by native or migratory aquatic, terrestrial, and avian species. Such habitats include, but may not be limited to, spawning sites, nursery areas, forage areas, and migratory pathways.

5.6.2.5 ERES standards shall not apply in excavated waters. All other appropriate criteria shall remain in force for these waters.

5.6.2.6 The ERES criteria set forth in subsection 5.6 supplement all other applicable requirements of these standards for ERES waters. Nothing in subsection 5.6 relieves or reduces the obligation of any person to comply with other requirements of these Standards, federal or state laws and regulations.

5.6.3 Pollution Prevention

5.6.3.1 Existing Sources: For the purposes of this Section, an existing source shall be defined as a discharge for which a permit has been issued by the Department pursuant to 7 Del.C. Ch. 60 prior to January 1, 1991. In the case of a water body designated as ERES waters pursuant to Section 3.0 of the Standards, the Department shall not issue or reissue a permit for an existing source unless the applicant demonstrates a utilization of all economically feasible and reasonably available waste minimization practices and technologies, and the lack of feasible alternative production processes and disposal options.

5.6.3.2 The provisions of subsections 5.6.1.4, 5.6.1.5, and 5.6.3.1 shall apply to existing sources on January 1, 1996, or upon adoption of a Pollution Control Strategy as provided in subsection 5.6.3.5, whichever occurs first. In either event, the provisions of subsection 5.6, including all requirements of the Pollution Control Strategy shall apply to existing sources.

5.6.3.3 Increased or New Sources: For the purposes of subsection 5.6, new sources are those discharges for which a permit has not been issued pursuant to 7 Del.C. Ch. 60 prior to January 1, 1991, and increased sources are those discharges for which there is an increase in the mass loading of any pollutant of concern from any existing source. For the purposes of subsection 5.6, pollutants of concern are the following: oxygen demanding substances (as may be measured by BOD and COD), nitrogen, phosphorous, bacteria, heat, and total suspended solids. In the case of any waterbody designated as ERES waters pursuant to Section 3.0 of the Standards, the Department shall not issue or reissue a permit pursuant to 7 Del.C. Ch. 60 that allows an increase in or new source of pollutant loadings of pollutants of concern unless the applicant demonstrates:

5.6.3.3.1 A need to discharge based upon a showing of the full utilization of measures, processes, methods, systems or techniques to eliminate the discharge altogether or minimize waste loadings through process changes, substitution of materials, enclosure of systems or other modifications. This can be demonstrated through the full utilization of available waste minimization practices and technologies and the lack of feasible alternative production processes and disposal options; and

5.6.3.3.2 That a proposed new discharge or any increase in loading of pollutants of concern of an existing discharge is consistent with the Pollution Control Strategy for the basin. Prior to adoption of a Pollution Control Strategy for a stream basin no increase in loadings of pollutants of concern shall be allowed to the stream basin from a surface water discharger unless the Secretary determines that:

5.6.3.3.2.1 Such discharger offsets the increased surface water discharge of pollutants of concern within the stream basin to the maximum extent practicable in an acceptable manner;

5.6.3.3.2.2 The increased loadings of pollutants of concern are necessary to prevent a substantial adverse economic or social impact at the community or regional level, and

5.6.3.2.2.3 Water quality will be maintained to fully protect existing uses.

5.6.3.4 Pollution Control Strategy

5.6.3.4.1 For each stream basin designated as ERES waters pursuant to Section 3.0 of these standards, the Department shall develop a pollution control strategy. The strategy shall provide for the implementation of best management practices established pursuant to subsection 5.6.3.5 of this section and shall include such additional requirements, measures, and practices as are necessary to:

5.6.3.4.1.1 Prevent the violation of water quality standards;

5.6.3.4.1.2 Protect all resources in the stream basin in a manner that allows for natural conditions to be maintained or restored; and

5.6.3.4.1.3 Assure the protection and propagation of a balanced, indigenous population of fish, shellfish, aquatic vegetation, and wildlife, and provide for recreational activities in and on the water.

5.6.3.4.2 The strategy pursuant to this subsection shall, at a minimum:

5.6.3.4.2.1 Provide an assessment of the nature, degree, and extent of pollution to waters within such stream basin, in terms of point source and non-point source contribution;

5.6.3.4.2.2 Identify the aspects of the stream basin which are important, unique, or sensitive from a recreational or ecological perspective;

5.6.3.4.2.3 Establish such additional indicators and criteria that satisfy the general policy and provisions established for such stream basins;

5.6.3.4.2.4 Identify the means by which ERES standards will be achieved;

5.6.3.4.2.5 Delineate, where appropriate, the specific point source effluent limits, best management practices, and other controls that will be used to achieve water quality standards; and

5.6.3.4.2.6 Indicate changes to be made to state plans for control of water pollution or resource management to assure implementation of the strategy.

5.6.3.4.3 The Department shall assure the opportunity for public participation in the development of the strategy required pursuant to this subsection and shall provide for public review and comment on the strategy in accordance with 7 Del.C. § 6010.

5.6.3.4.4 The Department may, to the extent it deems appropriate, provide technical assistance to local governments in developing and implementing the strategy required pursuant to this subsection.

5.6.3.4.5 The Department shall, to the extent it deems appropriate, pursue and coordinate implementation of any strategy developed pursuant to this subsection through priority application of its resources to ERES waters through its regulatory and non-regulatory programs.

5.6.3.4.6 The Department may, in accordance with 7 Del.C. § 6010, adopt and require the use of specific combinations of methods, practices, and technologies which it deems to be most effective for controlling, reducing, or removing waste loadings to ERES waters. Such requirements shall be based upon the application of good engineering and environmental science practices and principles, achieve a high degree of reliability, and be appropriate for the categories of activity.

5.6.3.5 Best Management Practices

The Department may adopt, pursuant to 7 Del.C. § 6010, best management practices for selected sources of pollution to ERES waters. Best management practices identified by the Department pursuant to this subsection shall provide a standard for the control of the addition of pollutants which reflects the greatest degree of pollutant reduction achievable including, where practicable, a standard requiring no discharge of pollutants.

7 Del. Admin. Code § 7401-5.0

14 DE Reg. 1392 (06/01/11)
21 DE Reg. 241 (9/1/2017)
26 DE Reg. 608 (1/1/2023) (Final)