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Vapor-Extraction Well Construction i - The vapor-extraction wells will be constructed with thread pointed, 2 or 4-inch-inner- diameter, Schedule 40 PVC casing No chemical cements, glues, or solvents will be used in well construction. The screened portion of the wells will consist of factory-perforated casing with 0.1-inch-wide slots with pea gravel placed in the annular space opposite the screen to a height of two feet above the screen zone. For the 2-inch dual well completion, a 12-inch diameter boring will be drilled to approximately 40 feet below surface grade (bsg). Approximately 7 feet of 0.1-inch slotted casing will be set through the clay interval and backfilled with pea gravel. A 2-foot thick bentonite seal will be added above the gravel pack A 2-foot thick quick-set cement will be placed above the bentonite seal. After the quick-set cement mixture has set, a second 2-inch diameter PVC slotted casing will be installed to a depth of approximately 10 feet bsg A second bentonite seal will be placed above the pea gravel pack. The remainder of the boring will be backfilled to grade with a bentonite cement slurry For the 4-inch well completion, a 10-inch diameter boring will be drilled to approximately 30 feet bsg. Approximately 15 feet of 0 1-inch slotted casing will be set through the sand interval and backfilled with pea gravel A 2-foot thick bentonite seal will be added above the gravel pack The remainder of the boring will be backfilled to grade with a bentonite cement slurry. The well will be protected with a traffic-rated, cast-aluminum utility box equipped with a PVC skirt The box has a watertight seal to protect against surface-water infiltration and must be opened with a special wrench The design of this box discourages vandalism and reduces the possibility of accidental disturbance of the well Disposal of Soil and Water Soil cuttings generated during drilling will be stored onsite and covered with plastic sheeting If possible, drill cuttings exhibiting subjective evidence of gasoline hydrocarbons or producing a positive response on the phototonization detector will be separated from those drill cuttings evaluated as having no gasoline hydrocarbons. Purge water will be stored in 55-gallon drums approved by the Department of Transportation until suitable disposal options can be selected based on laboratory analysis We will evaluate disposal options of soil and water, apprise the City of Stockton of disposal options 0 380Q9-SW 1