ARCHIVED REPORTS_XR0008461 - Laserfiche WebLink

Home Browse Search

25 January 2001 AGE-NC Project No 99-0559 Page 4 of 14 4.0. GROUNG WATER EXTRACTION TREATMENT DESIGN AGE anticipates that initiation of the proposed shallow ground water extraction, treatment and disposal system utilizing air-stripping and granular activated carbon vessels will retard or reverse the offsite migration of dissolved petroleum hydrocarbons and MTBE, and reduce the overall hydrocarbon/MTBE mass prior to full-scale mitigation 41 EXTRACTION WELL PUMP INSTALLATION AND PROCESS PIPING NETWORK Ground water will be initially be extracted from ground water monitoring wells MW-2 MW-3 and MW-4 to allow for immediate implementation of the proposed interim remediation system without the necessity to install extraction wells Grundfos Rediflow2 down-well pumps equipped with '/a-hp, 230V, 3-wire motors will be installed in each of the wells One-inch diameter Schedule 40 PVC pipe will be installed from each pump discharge to the surface with a safety chain to prevent dropping the pump to the well bottom The well system is rated to remove up to five-gallons of water per minute (gpm) To minimize sediment intake through the pump,the bottom of the pump/motor assembly will . be suspended approximately 5 feet above the well bottom Electrical wiring will be connected from the top of the pumps through Class I electrical connectors/unction boxes and electrical conduit to the pump controller The extraction well pumps will be controlled by PumpTec controllers and the ground water extraction pumps will each operate on an independent controller The pump controls will be supplied by an amperage sensing/time control switch This switch will detect a decrease of amperage when water level drops below the impeller intakes of the Grundfos pumps A network of two-inch diameter, schedule 80 PVC piping will be installed in a trench approximately '/2 foot wide by 1'/2 feet deep Schedule 80 PVC conduits for electrical pump power will also be installed within the trench The PVC piping will be routed from each ground water extraction well head to a water holding tank, the holding tank will be connected to the air-stripper, from which the piping will be directly connected to the GAC ground water treatment system AGE plans to install a 2-inch diameter, schedule 80 polyvinylchloride (PVC) pipe underground along the east side of the site to the City of Stockton discharge line located in Sutro Way AGE anticipates a continuous discharge of treated ground water from site to the City of Stockton sanitary sewer at a flow rate of approximately four gallons per minute A plan of the proposed piping system and enclosed unit location are depicted in Figure 4 AdvancedGeoi-nvironmtntal,inc