Laserfiche WebLink
RUSS CHAPIN 249-454-6947 11-17-95 07-'48 P.05 <br /> Mr, Rus%etl F.Chapin, St. <br /> Nnvennber 15, 1995 <br /> ll,agc 4 <br /> corner of thesite and another which would be located near the utheast st COMM lite <br /> lite <br /> Site 111011). We will Make use of the wells near the southwcs <br /> t and northerly parking area as vapor extraction wells Mid use the existing air sparging well as the 01111Yspatging point initially. It 1S oulf cipit}ion that the design as previously presented would lead to <br /> additional migration of'Contaminanls by forcing contaminants offsite to this east when air <br /> srtjrping is initiated at the proposed locations. <br /> VapULWCll(;set amnion <br /> All vafwf extraction wells will be constructed using flush-jointed,4-in inner diameter, <br /> Schedule 44 polyvinyl chloride (PVC)casing set to depths of 25 to 30 ft. No chemical cements, <br /> Fh�rs,of solvents will be used in well constntetion. The bay of each well will be felted wide a <br /> lhrej►dcd f'VC" plug, The screened portion of each well will consist of factory-perforated casing <br /> With 0.(tti4-iri-wide slots. 'rhe well screen will be set through the augers and will extend from the <br /> t(+tal depth of the boring to approximately 5 f3 below the groundlsurface. The annular space of <br /> the well will lie packed with sorted sand to a point approximately 0.5 ft above the top often <br /> perforated es-,ing. A 2-ft thick plug consisting of bentonite pellets or chips will be placed above <br /> the sated in tl)c wells to prevent cement from entering the sand pack. The remaining annulus will <br /> 1)e biwkfillcd with a mixture of neat cement and powdered bentonite to grade. <br /> Soil satrtplcs will be collected at maximism 5-ft intervals and tit lithologic contacts in the <br /> b()rir>,gs using it California-modified split-spoon gturtpler fitted with clean brass sleeves. Soil <br /> saniples from ca►ch sample interval will be sealed sand placed in iced storage for possible <br /> loboratory analysis. A photoionizing organic vapor meter(OVM)will he used during sampling <br /> to detect polential hydrocarbon concentrations in the sell samples. Two soil samples from each <br /> boring will tic analyzed for TPfig using EPA Method 8415 (modified) and for BTf:X using LPA <br /> Method 8020 <br /> 1}ESJ(sN ANU INSTALL SYSTEM <br /> Thr rerrtie�lial s}stern selected for installation will be designed, permitted,and installed. <br /> ilei"phase will include appropriate negotiations with agencies regulaiing soil find grnundwater <br /> cissessment and cleanup projects.air emissions,sewer disposal of treated water,and others. The <br /> system recommended is capable of extracting and treating both soil vapor and groundwater,and <br /> will include subgradc trenches for extraction And ;parging lines. <br /> ansa-c3 l <br />