ARCHIVED REPORTS_XR0004041 - Laserfiche WebLink

Home Browse Search

1 promptly placed in iced storage for transport to the laboratory Chain-of-custody records were initiated In the field by the geologist and accompanied the samples to a laboratory certified by the ' state of California to perform the analyses requested Vapor Extraction Well Construction ' The vapor extraction well was constructed in the boring with thread-,jousted, 2-inch-inner-diameter, Schedule 40 polyvinyl chloride (PVC) casing No chemical cements, glues, ' or solvents were used in well construction The screened portion of the well consisted of factory perforated casing with 0 020-inch-wide slots The annular space In the well was packed with number 3 sand to approximately 2 feet above the slotted interval A 3-foot-thick bentonite plug was added above the sand pack to prevent the cement grout from entering the well pack The remain-mg annulus was backfilled to grade with neat cement grout See Appendix B for well details sheets ' The well was protected with a traffic-rated, cast-aluminum utility box equipped with a metal sku-t The box has a watertight seal to protect against surface water infiltration The design of this box ' discourages vandalism and reduces the possibility of accidental disturbance of the well ' Groundwater Monitoring Well Construction The groundwater monitoring wells were constructed in the borings with thread-jointed, 2-inch-ismer-diameter, PVC casing No chemical cements, glues, or solvents were used in well construction The screened portion of the wells consisted of factory perforated casing with 0 020-inch-wide slots The well screen extends from the total depth of the well to approximately ' 10 feet above the groundwater surface The annular space in the wells was packed with number 3 sand to approximately 2 feet above the slotted interval A 2-foot-thick bentonite plug was added above the sand pack to prevent the cement from entering the well pack The remaining annulus ' was backfilled to grade with neat cement or a bentonite cement grout See Appendix B for well detail sheets ' The well was protected with a traffic-rated, cast-alurrunum utility box equipped with a metal skirt The box has a watertight seal to protect against surface water infiltration The design of this box ' discourages vandalism and reduces the possibility of accidental disturbance of the well Well Development EMCON waited a mirumum of 24 hours after well installation before develo its the groundwater developmg ' monitoring wells to allow the grout to seal Before developing the monitoring wells, a technician measured depths to water with an oil/water interface probe Floating product was not encountered The well was developed with a surge block and pump Well development continued until the discharge water was clear of silt and sand Clay-size sediments derived from the screened portion of the formation cannot be entirely eliminated by well development 5A['\N VJZ\260SQ6051010 1 B5 97\cJb 2 A-2 EAKOf1 22605-101 001 Rev 0 814/97