ARCHIVED REPORTS XR0006890 - Laserfiche WebLink

Home Browse Search

1 The respective sample containers were labeled in the field with the .job number, sample location, depth if applicable, and date, and promptly placed to iced storage for transport to the laboratory Chatn-of-custody records were initiated to the field by the geologist and accompanied the samples to a laboratory certified by the State of California to perform the analyses requested Air Sparge Well Construction The air sparge well was constructed to the boring with thread-jointed, ' 2-inch-inner-diameter, Schedule 40 polyvinyl chloride (PVC) casing No chemical cements, glues, or solvents were used to well construction The screened portion of the well consisted of factory perforated casing with 0 020-inch-wide slots The well screen ' extends approximately 1 9 feet from the total depth of the well The annular space in the well was packed with No 3 sand to approximately 0 9 foot above the slotted interval A ' 5 5-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 a bentonite cement slurry The well was 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 Wei'. Jeveiopmen's ' We waited a muumum of 24 hours after well installation before developing the air sparge well to allow the grout to seal Before developing the air sparge well, the water level was measured 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 Water purged from the well was stored to labeled, 55-gallon steel drums approved for this use by the Department of Transportation until suitable disposal options were selected based on laboratory analysis Groundwater Sampling tThe static water level in each well was measured to the nearest 0 01 foot with a Soltnst electric oil/water interface probe, steamed-cleaned before use to each well Approximately ' four casing volumes of groundwater were purged from the wells using a stainless-steel electrical submersible pump The pump, cables, and hoses were cleaned with a laboratory grade, non-phosphatic detergent and water before use to each well The wells were purged until withdrawal was of sufficient duration to result to stabilized pH, temperature, and electrical conductivity of the water, as measured by portable meters calibrated to a SAC\N IPJ(AOF9010F900020 4cs-95 PAS 2 A-2 Rev 0 8122/95