ARCHIVED REPORTS XR0000308 - Laserfiche WebLink

Home Browse Search

Chevron Groundwater Monitoring Report(l Q2001) Page 2 of 2 Facility: #9-4275—2905 West Benjamin Holt Drive,Stockton,CA Date: April 18,2001 DISCUSSION: Gettler-Ryan Inc. performed this groundwater monitoring and sampling for nine site wells and one municipal well on March 2,2001. Duplicate groundwater samples were collected and submitted to Sequoia Analytical of Walnut Creek, California(S)and Kiff Analytical of Davis,California(K)for analysis of total petroleum hydrocarbons as gasoline(TPHg), benzene,and methyl tertiary butyl ether(MtBE). Analytical methods include DHS/LUFT or EPA Method 8260B. Laboratory results were generally in agreement for each analysis. Analytical results for groundwater from monitoring well(MW)-2 comprised the sole detection of TPHg at 1400 ug/L(S)/1,800 ug/L(K). Benzene was detected by the laboratories in groundwater samples from MW-2 at 25 ug/L (S)/10 ug/L(K), MW-8 at 0.50 ug/L (S)/<0.5 ug/L(K),and in MW-6 at 0.55 ug/L(S)/<0.5 ug/L(K). MtBE was detected by the laboratories in groundwater samples from MW-I at 1,300 ug/L(S)/970 ug/L(K), MW-2 at 410 ug/L(S)/380 ug/L(K), MW-3 at 430 ug/L(S)/400 ug/L(K), MW-4 at 96 ug/L(S)I90 ug/L(K),MW-5 at 7.5 ug/L (S)/6.1 ug/L(K), MW-6 at<2.0 ug/L(S)/0.59 ug/L(K), MW-7 at<2.0 ug/L (S)/0.63 ug/L(K),MW-8 at<2.0 ug/L(S)/0.96 ug/L(K),MW-9 at 62 ug/L(S)/45 ug/L(K),and in Municipal Well No. 10 at<2.0 ug/L(S)/0.57 ug/L(K). Groundwater elevations across the site generally increased this quarter. Groundwater flow was north to northeast at 0.003 to 0.005 ft/ft. LIMITATIONS: The findings presented in this letter are based on data and interpretations provided by Gettler-Ryan, Inc. Gettler- . Ryan's report is attached. The data presented in this summary is accurate only to the degree implied by the sources and methods used. No warranty, expressed or implied, is made by SECOR. If you have any questions, please feel free to call us at(916)861-0400. Sincerely, SECOR Intern . al Inc. cott Gable Senior Geologist ATTACHMENTS: Attachment A—March 20,2001 Groundwater Monitoring& Sampling Report by Gettler-Ryan Inc. cc: Bob Cochran,Chevron Products Company, P.O. Box 6004, San Ramon,CA 94583-0804 Marty Hartzell, RWQCB-CVR, 3443 Routier Road, Suite A, Sacramento, Ca 95827