Landfill means a disposal facility or part of a facility where hazardous waste is placed in or on land and which is not a pile, a land treatment facility, a surface impoundment, an underground injection well, a salt dome formation, a salt bed formation, an underground mine, a cave, or a corrective action management unit.
Landfill Gas means any gas derived through any biological process from the decomposition of waste buried within a waste disposal site.
Landfill cell means a discrete volume of a hazardous waste landfill which uses a liner to provide isolation of wastes from adjacent cells or wastes. Examples of landfill cells are trenches and pits.
Sanitary landfill means a disposal facility for solid waste so located, designed and operated that it
Transportation project or "project" means any or the
Wastewater treatment unit means a device which:
Wastewater means the spent water of a community. From the standpoint of source, it may be a combination of the liquid and water-carried wastes from residences, commercial buildings, industrial plants, and institutions, together with any groundwater, surface water, and storm water that may be present.
Natural area means an area of the rural or non-urban environment which is in an unspoilt natural state or is of high scenic value, and includes, but is not limited to, national parks, game reserves, nature reserves, marine reserves, wilderness areas, areas of extensive agriculture and scenic areas.
Wastewater treatment tank means a tank that is designed to receive and treat an influent wastewater through physical, chemical, or biological methods.
Wastewater treatment plant means a facility designed and constructed to receive, treat, or store waterborne or liquid wastes.
Clean wood means natural wood which has not been painted, varnished or coated with a similar material, has not been pressure treated with preservatives and does not contain resins or glues as in plywood or other composite wood products.
Ex-situ conservation means the conservation of components of biological diversity outside their natural habitats.
Water Surface Elevation (WSE means the height, in relation to NAVD 1988, of floods of various magnitudes and frequencies in the floodplains of riverine areas.
in situ conservation means the conservation of ecosystems and natural habitats and the maintenance and recovery of viable populations of species in their natural surroundings and, in the case of domesticated or cultivated species, in the surroundings where they have developed their distinctive properties.
Stormwater runoff means water flow on the surface of the ground or in storm sewers, resulting from precipitation.
Sewerage system means pipelines or conduits, pumping stations, and force mains, and all other
Waste load allocation means (i) the water quality-based annual mass load of total nitrogen or
Transportation district means a district organized under ORS 267.510 to 267.650.
Wastewater Treatment Works means an arrangement of devices and structures for treating wastewater, industrial wastes, and sludge. Sometimes used as synonymous with "waste treatment plant" or "wastewater treatment plant" or "pollution control plant".
Water surface elevation means the height, in relation to the National Geodetic Vertical Datum (NGVD) of 1929, the North American Vertical Datum (NAVD) of 1988, or other datum, where specified, of floods of various magnitudes and frequencies in the floodplains of riverine areas.
Uppermost aquifer means the geologic formation nearest the natural ground surface that is an aquifer, as well as lower aquifers that are hydraulically interconnected with this aquifer within the facility's property boundary.
Surface impoundment or "impoundment" means a facility or part of a facility which is a natural topographic depression, man-made excavation, or diked area formed primarily of earthen materials, although it may be lined with man-made materials, which is designed to hold an accumulation of liquid wastes or wastes containing free liquids, and which is not an injection well. Examples of surface impoundments are holding, storage, settling, and aeration pits, ponds, and lagoons.
Excavation zone means the volume containing the tank system and backfill material bounded by the ground surface, walls, and floor of the pit and trenches into which the UST system is placed at the time of installation.
Gasohol means a blended fuel composed of gasoline and fuel grade ethanol.
industrial effluent means any liquid, whether or not containing matter in solution or suspension, which is emitted in the course of or as a result of any trade or industrial operation, including a mining operation, and includes any liquid besides soil water or waste water or stormwater;
Assessment area means an area, or, if more than one area is designated, the