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GRANITE CONSTRUCTION, FRENCH CAMP WKA No 2088 03 April 29, 1993 Page 3 I Monitoring Well Construction Borings MW-1 through MW-3 were drilled and sampled as described above and converted to monitoring wells Each well was constructed using two-inch diameter, flush pointed, Schedule 40 PVC casing, 0 02-inch slotted casing was used for the screened interval Number 3 sand was trem►ed into the well annulus as a filter pack The filter pack extended from the bottom of the screened interval to approximately two feet above the top of the screened interval A two-foot thick bentonite seal was placed in the well annulus above the filter pack A grout seal consisting of a Portland Cement and bentonite slurry was tremied into the well annulus above the bentonite seal Each well was completed with a locking well cap and a flush-mounted, traffic-rated well cover As-built well diagrams are presented on Plates 21 through 23 Monitoring Well Development, Purging and Sampling After well construction was completed, the water level in each well was measured with an electronic well sounder and the wells were checked for free product using a clear bailer The ' wells were subsequently developed using a vented surge block Approximately three well volumes of water were then removed by hand bailer until temperature, pH and conductivity readings stabilized and/or the water cleared of sediment After a minimum of 24 hours from the time of development, the water level in each well was measured, and the water checked for visual signs of free product using a clear bailer Approximately three to five additional well volumes of water were purged using a clean, submersible pump until temperature, pH, and conductivity readings stabilized and/or the water cleared of sediment The water samples were then collected using new polyethylene disposable bailers Water from the bailers was decanted into appropriate sample containers provided by the laboratory I The samples were immediately placed in an ice-chest with ice, along with a travel blank, 'and submitted under chain-of-custody to a California-certified laboratory for analysis of Total Petroleum Hydrocarbons (TPH) using EPA method 8015, and Benzene, Toluene, Ethylbenzene and Total Xylenes (BTEX) using EPA method 602/Purge and Trap The travel blank provided 6 by the laboratory also was analyzed for TPH and BTEX WALLACE DDDDDQ R.cycicd paper &ASSOCIATESJL INC