Laserfiche WebLink
WATERWORK <br /> GEOCHEMICAL• GEOTECHNICAL•ENVIRONMENTAL <br /> RECEIVEO- <br /> June 22 1990 <br /> JUN 2 5 1990 <br /> ENVIRONMENTAL <br /> LTH <br /> Ms., Elanor Ratliffiff <br /> PERMIT/SERVICES <br /> San Joaquin County Public Health Division <br /> Post Office Box 2009 <br /> Stockton, CA 95201 <br /> i <br /> Re: Western Stone Products, 8181 West 11th Street, Tracy, <br /> Clef <br /> Dear Bill: <br /> This letter is being submitted in response to the April 18, 1990 <br /> request by the San Joaquin County Public Health Services, <br /> Environmental Health Division for additional investigation at the <br /> above referenced site ( Figure 1 ) . In addition, for your <br /> convenience WaterWork has included the quarterly <br /> monitoring/sampling results for the new well and 3 existing <br /> f-'sJ <br /> wells. <br /> I' <br /> On May 22, 1990, a soil boxing was drilled 5 feet downgradient of <br /> the former tank pit for the purpose of installing groundwater <br /> monitoring well MW-4 (Figure 2) . The soils encountered consisted <br /> of clay to 5.5 feet, sand and silt to approximately 14 feet and <br /> clay to 21 feet below grade the maximum depth explored. <br /> Drilling was conducted by Sierra Drilling (C52 license #521617) <br /> using 8 inch outside diameter (O.D. ) hollow stem augers. During <br /> drilling, soil cuttings were logged continuously by a field <br /> geologist utilizing the Unified Soil Classification System. <br /> Descriptions of soils encountered and well construction are <br /> presented on the well log (Attachment 1) . dydrocarbon odors <br /> were detected between 10 and 14 feet below grade. Groundwater <br /> was first encountered at approximately 6 feet below grade. <br /> i <br /> Subsequent to installation, the wellheads were survayed to a <br /> common datum and two rounds of water level measurements wE e <br /> performed (Table 1 ) . The monitoring data indicate the <br /> groundwater gradient is generally northwest at approximately <br /> 0.004 ft/ft (Figure 3) . <br /> A soil sample was collected at 5.5 feet, near the top of the <br /> capillary zone. The sample was contained, preserved and <br /> transported under chain-of--custody to Sequoia Analytical, a state <br /> certified hazardous waste laboratory. The sample was analyzed <br /> for benzene, toluene, ethylbenzene, xylenes (STEX) k.nd total <br /> ':.i�s.,i!!5'REc� • ESC,.� :.v ;-%.4,,32C• • ;20¢; 83B-35L? <br /> f i:SN �h;?04, ��2 344 • <br /> PRc NvV ?0 j 78' 6830 <br />