Laserfiche WebLink
IT Corporation <br /> 4005 Pott Chirip) Ilt�ltx.tti <br /> Concord C 1 94520-1120 <br /> . Tel 925 288 9898 <br /> Fj% 925 288 0888 <br /> *he � <br /> � 'Uup d llembr r of Thi IT Group <br /> 1 � <br /> December 27, 1999 <br /> 1 <br /> Mr Bob DeNinno <br /> 7-Eleven, Inc <br /> 10220 S W Greenburg Road, Suite 470 <br /> Portland, Oregon 97233 <br />' Subject Fourth Quarter 1999 Monitoring and Sampling Report <br /> 7-Eleven Site No 17334 <br /> 4501 North Pershing Avenue <br />' Stockton, California <br /> IT Corporation Project 779950 <br /> Dear Mr DeNinno <br /> This Fourth Quarter 1999 Monitoring and Sampling Report presents the results of monitoring and sampling <br /> activities performed by IT Corporation at the subject site (Figures 1 and 2, Attachment 1) on November 24, <br /> 1999 A summary of activities conducted during this reporting period is provided below <br /> ■ Depth to water(DTW)was gauged in five site-related groundwater monitoring wells <br /> (MW-2 through MW-4 and wells MW-5A and MW5-B) <br /> ■ Groundwater samples were collected from five monitoring wells (MW-2, MW-3, MW-4, MW-5A <br />' and MW-513) and submitted to a California-certified laboratory for analysis of benzene, toluene, <br /> ethylbenzene and total xylenes (BTEX), methyl-tert-butyl-ether(MTBE), tert-butanol (TBA), <br /> dnsopropyl ether(DIPJ=), ethyl-tert-butyl ether(ETBE), tert-amylmethyl ether(TAME), and total <br />' petroleum hydrocarbons-as-gasoline (TPH-G) <br /> Groundwater Monitoring Data <br /> Quarterly groundwater monitoring of the wells was performed on November 24, 1999 Before monitoring, <br /> the well caps were opened to allow the water in each well to stabilize to atmospheric pressure The DTW <br /> rwas measured to the nearest 0 01 foot from the top of the well casing using an interface probe, and the <br /> resulting data was used to prepare a potentiometric surface map (Figure 2) Based on the potentiometric <br /> r surface map, groundwater flow is toward the northeast at an approximate gradient of 0 004 foot per foot <br /> Groundwater monitoring results for the quarter and historical monitoring results are presented in Tables 1 <br /> and 2, respectively (Attachment 2) Field data sheets are included in Attachment 3 <br /> r <br /> • <br /> r <br /> r <br />