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CLEARWATER G R O U P I N C Ennnonnientni Services information regarding the down gradient distribution of dissolved-phase contaminants,thus it is important to re-install the well in or near the same location Prior to drilling,Clearwater will prepare site specific Health and Safety Plan for drilling activities Prior to conducting and drilling, the site will be marked by Underground Service Alert (USA) to identify utilities leading to the site Appropriate well installation permits will be obtained prior to the start of fieldwork All fieldwork will be conducted in accordance with Clearwater's Field Protocols(attached) A hollow-stem auger truck mounted drill-rig will be usedlaccomplish drilling and well installation Clearwater personnel will supervise a C-57 licensed driller in these activities The driller will use the same size diameter augers(8-inch outer diameter)to over-drill the well as were used during original installation activities The driller will be directed to remove the existing well casing intact from the boring The boring will be advanced to a depth of 20 feet bgs,the original depth of the first boring After all well materials and annular fill have been removed from the boring, a new well will be constructed It is anticipated that the well will be constructed in the same manner as it was previously installed The well will be constructed of clean, flush-threaded,PVC well materials Well screen, with 0 02-inch perforations, will extend from 19 feet bgs to 5 feet bgs,and blank casing will be extended to ground surface A filter pack of Lonestar#3 sand will extend • from the bottom of each boring to one foot above the screened interval The filter pack will be sealed by a two-foot layer of hydrated bentonite The remaining annular space will be filled with cement and a tamper-resistant box will be concreted in place over the wellhead Proposed well construction details are shown on Figure 3 The well will be developed by surging and bailing Development will involve the removal of water from each well until such time that it is relatively free of sediment, and pH, temperature, and conductivity parameters have stabilized It is anticipated that the water volume removed will not exceed ten saturated casing volumes Augers will be steamed cleaned between use Rinseate and soil cuttings will be stored on-site in labeled 55-gallons drums pending future removal and disposal Clearwater will survey the top of casing elevation for the new well relative to a permanent benchmark, accurate to within ±0 01-feet Groundwater Momtorm2 Following re-installation of well MW-5,Clearwater recommends continued monitoring and sampling of groundwater at the site for the next several quarters to further evaluate trends in residual dissolved-phase contaminant levels and potential variability in seasonal hydrogeologic conditions All sampling will be performed in accordance with Clearwater's Field Protocols(attached) Clearwater recommends the following sampling schedule Ms Lori Duncan 4 September 30 1999