Support Document for the EPA (Environmental Protection Agency) Designation of the Cross Valley Aquifer as a Sole Source Aquifer (Revised)

摘要

On July 29, 1982, the Cross Valley Water Association, Inc. and the Mount Forest Protection Association submitted a petition requesting the EPA Administrator designate the Cross Valley Aquifer as a sole source of drinking water for the area. The Cross Valley Aquifer is located in southern Snohomish County and northern King County within the State of Washington. The 36 square mile area is located northeast of Seattle, Washington in and around the town of Clearview, Washington. Approximately 11,400 persons are served by the aquifer. The water use from the aquifer was approximately 60.6 million cubic feet in 1986. This is 77.6 percent of the total water use in the designated sole source aquifer. The water bearing geologic unit is glacial outwash termed the Esperance Sand according to the US Geological Survey nomenclature. Depth to the Esperance Sand unit averages about 200 feet, which is below the glacial till mantle. Water quality tends to be satisfactory.