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Protocol 7 <br />{i <br /> Monitoring Well Drilling � <br /> All down-hole equipment was decontaminated using steam to clean off all soil <br /> equipment before use Wells were drilled with a 8 25 inch hollow stem-auger All wells <br /> have a diameter that is 4 inches greater than the casing diameter(OD) Soil samples were <br /> collected every five feet and blow counts were recorded <br /> A soil sample from the capillary fringe was obtained in each boring The wells <br /> were logged geologically and all appropriate information is included in the well log <br /> attached In addition, the odor of each sample was noted and the presence of free <br /> hydrocarbon product was recorded <br /> Prior to removing equipment from the hole, the total depth was measured The <br /> presence of floating free product was checked by noting the depth of the water and <br /> marking that level on the probe wire The probe and wire was withdrawn from the well <br /> and dried Chalk was placed on the probe and up the side of the wire of two feet The <br /> probe was then carefully lowered into the well so that the probe dust touched the water <br /> table, care was taken not to lower the probe below the water table Once the probe <br /> signaled the water table the probe was withdrawn quickly from the well and the liquid <br /> level above the water level point on the probe was measured Once the casing was placed <br /> in the hole, an accurate measurement of the casing was made <br /> All drill cuttings were placed in sealed DOT drums The drilling intervals for the <br /> cuttings in each drum was marked on the drum The drums were stored at the site <br /> pending further analysis and proper disposal <br /> • <br /> Completion <br /> Slotted casing (0 02 inch slots) was capped with a bottom plug The screen <br /> interval extended 5 feet above and 10 feet below the water table estimated during drilling <br /> A sand filter pack was placed in the annulus throughout and one foot above the slotted <br /> casing interval The well was then surged for 5 minutes to attempt to eliminate any voids <br /> in the sand pack At the end of the surging, the top of sand was measured and additional <br /> sand was added if necessary Directly above the sand, a 3-foot plug of hydrated bentonite <br /> chips was placed Above the plug, a seal of bentonite cement grout was placed to the <br /> surface The top of the casing was capped and a traffic rated box was cemented in place <br /> around and above the top of the casing The cement or bentonite grout was placed in the <br /> annulus by use of a tremme pipe (Bul 74-90 CA Water Well Standards) <br /> The wells were developed by bailing to remove most of the sediment within the <br /> casing and to remove bridging fines within the slots and the sand pack Tins was done by <br /> surging, using the well water if possible <br /> All purged water was stored in drums The drums were sealed and left on site until <br /> the condition of water is assessed <br /> • <br />