Laserfiche WebLink
S t 1 <br /> • r { <br /> time sampled and analysis) , sealed in zip lock baggies, placed in <br /> a cooler with ice and cooled to 4-C. The samples were then chain <br /> t of custody, hand delivered to the, laherstary perfefCsLA9 thO <br /> Analysis (Chamtech) . <br /> Sail samples were obtained from the borings of the vapor <br /> & , extraction wells using a California split spoon -sampler that - - - - <br /> contains 3 2"x6" stesrila brass sleeves. A 140 pound drop hammer <br /> powered by Hogates Drilling cathead was used tv drivo the ZAMPler <br /> and "blows count" required to drive 6" were recorded. The <br /> excavations were sampled by hand angering a 6" diameter hole sic <br /> inches below the base 01 the excavation, than cbtai.ning the sample <br /> by hand driving a 20x6" sterile brass sleeve that had been <br /> g inserted into a barrel sampler attached to rod extensions and a <br /> slam bar. Between sample intervals both samplers were cleaned <br /> with trisodium phosphate and clean water rinse. upon obtaining <br /> the soil samples, the sleeves were withdrawn from the sample <br /> barrel and the uncovered ends were screened with the KNU-PID, then <br /> the sleeved sample exhibiting the highest response from the PID <br /> was sealed with aluminum foil, plastic end caps, then sealed with <br /> a��t ts%.o, ia}�a1ad. Vaut 3 ntn m =!Lv Teale fr002Qr baa and placed <br /> upon dry $oe in A eoot6v fbv IsrasaYVAtim. 'idle Ch&ift of eugtadY <br /> was filled out prior to leaving the site and the samples were hand <br /> i delivered to ChemTech Laboratories EBtate of California Cert. # <br /> Bao ���--••1YGig� BOG Ilti?n4luR��Y � <br /> on Maysmber 27 3.666, ME parformaa A 61uIJ taAt 8ft All 8f the <br /> ground water monitoring wells (MVI, ?lW2, MW3, MW4, XV5, and KV6) . <br /> Using the Bouwer and Rice method for predicting hydraulic <br /> conductivities (K) ground Wates velacitie® were calculated, see <br /> Figure 5 and Tables 3 X11 thru MV6. The results of the slug test <br /> shoved that the formation near the wells is of a silty fine sand <br /> with the highest ground grater velocity being near Mw1 and forms a <br /> velocity dome at this well which spreads southeast and northwest <br /> towards monitor wells MV6 and MW2, see Figure 5. Using the <br /> velocity from MW2, downgradient well, the contaminant plume would <br /> travel lose than 5 feet is one year. <br /> r VAPOR EXTRACTION PILOT TEST <br /> At completion of the construction of the vapor extraction wells a <br /> request was made to San Joaquin County Air Quality Board (SJC-AQB) <br /> to perform a source-pilot test for vapor extraction of the <br /> gasoline range hydrocarbons stili present near the over- <br /> excavations of the tank field and pump island areas. The <br /> recovered vapors were absorbed onto activated charcoal and then <br /> destroyed by regeneration of the charcoal by Cameron-Yakama. <br /> page 7 <br /> i <br />