Definitions. As used in this section, the following terms shall have the meanings indicated:
ABOVEGROUND STORAGE TANK (AST)A single containment vessel greater than 250 gallons as defined in the Delaware Regulations Governing Aboveground Storage Tanks. ASTs with a storage capacity greater than 12,499 gallons containing petroleum or hazardous substances and ASTs with a storage capacity greater than 39,999 gallons containing diesels, heating fuel or kerosene are subject to the design, construction, operations, and maintenance requirements of the Delaware AST regulations.
BEST MANAGEMENT PRACTICESStructural, nonstructural and managerial techniques that are recognized to be the most effective and practical means to control nonpoint source pollutants yet are compatible with the productive use of the resource to which they are applied. Such techniques can include applying the principles of filtration, infiltration and storage most often associated with natural vegetation and undisturbed soils while minimizing a reliance on structural components. They may also be constructed using an imported soil medium and planted with vegetation designed to promote the natural hydrologic process. These practices include, but are not limited to, vegetative filtration, riparian buffer plantings, bioretention areas, vegetative flow conveyance, as well as recharge and surface storage in undisturbed natural areas. These are used in both urban and agricultural areas.
CONTAMINATIONAny physical, chemical, biological, or radiological substance that enters the hydrologic cycle through human action and may cause a deleterious effect on groundwater resources.
ENVIRONMENTAL ASSESSMENT REPORTDocuments that post-development recharge will be no less than predevelopment recharge for both water quality and quantity when computed on an annual basis. The environmental assessment report at a minimum needs to include the following elements:
(1) Site description of proposed development within the water resource protection area.
(2) Climatic water balance comparing predevelopment and post-development recharge potential for both water quantity and quality.
(3) Subsurface exploration, including borings, test pits, and infiltration tests.
(4) Design of groundwater recharge facilities that assure water quality as well as water quantity.
(5) Construction and maintenance considerations.
(6) Recommended groundwater monitoring plan.
(7) Water management agreement between the applicant and the County providing for monitoring and maintenance of the recharge system. The applicant will abide by the groundwater management agreement as written in the DNREC Supplement to the Source Water Protection Guidance Manual for the Local Governments of Delaware: Ground-Water Recharge Design Methodology, dated May 2005, or as later revised.
EXCELLENT GROUNDWATER RECHARGE AREASThose areas with a high percentage of sand and gravel that have excellent potential for recharge as determined through a stack unit mapping analysis delineated by the Delaware Geological Survey and presented in the Report of Investigations No. 66, Ground-Water Recharge Potential Mapping in Kent and Sussex Counties, Delaware, Geological Survey, 2004. Excellent Groundwater Recharge Areas are delineated on the Excellent Groundwater Recharge Area Maps described in Subsection
B(1) of this section.
GROUNDWATERThe water contained in interconnected pores located below the water table in an unconfined aquifer or located in a confined aquifer.
HAZARDOUS WASTEA solid waste or combination of solid wastes which because of its quantity, concentration, or physical, chemical, or infectious characteristics may cause or significantly contribute to an increase in mortality or an increase in serious irreversible or incapacitating, irreversible illness, or pose a substantial present or potential hazard to human health or the environment when improperly treated, stored, transported, or disposed of, or otherwise managed. Without limitation, included within this definition are those hazardous wastes described in Sections 261.31, 261.32, and 261.33 of the Delaware Regulations Governing Hazardous Waste.
IMPERVIOUS COVERThe sum of parking lots, roads, buildings, sidewalks, or other created surfaces through which rainwater cannot pass or infiltrate the soil. Materials such as permeable pavers, permeable concrete or asphalt, and permeable plastic grid systems, shall not be considered impervious.
INFILTRATIONThe passage or movement of water through the soil profile.
LAND-DISTURBING ACTIVITYA land change or construction activity for residential, commercial, industrial, and institutional land development which may result in soil erosion from water or wind, or the movement of sediments or pollutants into state waters or onto lands in the state; or which may result in accelerated stormwater runoff, including, but not limited to, clearing, grading, excavating, transporting and filling of land.
LEADERSHIP IN ENERGY AND ENVIRONMENTAL DESIGN (LEED)A rating system developed and administered by the U.S. Green Building Council based in Washington, DC. It is designed to promote design and construction practices that increase profitability while reducing the negative environmental impacts of buildings and improving occupant health and well-being. The LEED rating system offers four certification levels for new construction which includes Certified, Silver, Gold and Platinum, corresponds to the number of credits accrued in five green design categories: sustainable sites, water efficiency, energy and atmosphere, materials and resources and indoor environmental quality. LEED standards cover new commercial construction and major renovation projects, interior projects and existing building operations.
ON-SITE WASTEWATER TREATMENT AND DISPOSAL SYSTEMConventional or alternative wastewater treatment and disposal systems installed or proposed to be installed on land of the owner or on other land to which the owner has the legal right to install the system.
RUNOFFThat portion of precipitation or snow melt that has not evaporated or infiltrated into the soil, but flows on land or impervious surfaces.
SANITARY LANDFILLA land site at which solid waste is deposited on or into the land as fill for the purpose of permanent disposal, except that it will not include any facility that has been approved for the disposal of hazardous waste under the Delaware Regulations Governing Hazardous Waste.
STORMWATERThe runoff of water from the surface of the land resulting from precipitation or snow or ice melt.
STORMWATER MANAGEMENT(1) For water quantity control, a system of vegetative, structural, and other measures that may control the volume and rate of stormwater runoff, which may be caused by land-disturbing activities or activities upon the land; and
(2) For water quality control, a system of vegetative, structural, and other measures that control adverse effects on water quality that may be caused by land-disturbing activities upon the land.
UNDERGROUND STORAGE TANK (UST)One or a combination of tanks including underground pipes, the volume of which is 10% or more below ground, as defined in the Delaware Regulations Governing Underground Storage Tank Systems, dated March 12, 1995. The following USTs are not subject to the design, construction, operation, and maintenance requirements of the Delaware UST Regulations: residential heating fuel, agricultural, and residential motor fuel USTs less than 1,100 gallons, and any UST less than 110 gallons.
WATER QUALITYThose characteristics of stormwater runoff from an impervious surface or a land-disturbing activity that relate to the chemical, physical, biological, or radiological integrity of water.
WATER QUANTITY(1) Those characteristics of stormwater runoff that relate to the volume of stormwater runoff to downstream-gradient areas resulting from land-disturbing activities.
(2) Those characteristics of stormwater that relate to the volume of stormwater that infiltrates the land surface and enters the underlying aquifer.