ARCHIVED REPORTS XR0000768 - Laserfiche WebLink

Home Browse Search

SECOR www secor cam ® INTERNATIONAL. 3017 Kilgore Road Suite 100 9 INCORPORATED Rancho Cordova CA 95670 916-861-0400 TEL # 916-861-0430 Fax nFC OVED 4 No 17 2003 S November 13, 2003 ENVIRONMENT HEALTH � PERM ISISERVIGES r Mr Michael Infurna San Joaquin County Public Health Services Environmental Health Division 304 East Webber Avenue, Third Floor Stockton, CA 95202 Re Results of Irrigation Well Sampling and Influence Study Circle K Store 1205 16470 Cambridge Street, Lathrop, CaliforniaF SECOR Project No 77CP 61205 06 00010 Dear Mr Infurna This letter, prepared by SECOR International Incorporated (SECOR) on behalf of ConocoPhillips, presents the results of the sampling of Lathrop Grammar School's irrigation well and the findings of a pumping well influence study for the site referenced above (Figure 1) The objective of this work was to verify that Lathrop Grammar School's irrigation well had not been impacted by petroleum hydrocarbons, particularly MtBE, and to determine if any pumping wells in the area may be affecting groundwater flow at the site This work was performed as required in San Joaquin County Environmental Health Division (SJCEHD) letter dated May 8, 2003 (Attachment A) LATHROP GRAMMER SCHOOL IRRIGATION WELL SAMPLING ;3 The Lathrop Grammar School irrigation well is located approximately 1,600 feet northeast of the site and Is the closest of three wells Identified during a 2000-foot radius receptor survey conducted at the site Per the requirements of SJCEHD, SECOR and ConocoPhillips contacted the well owner (Manteca Unified School District) to gain access to the well to collect a water sample and to obtain operational Information of the well Based on conversations with Mr Jerry Brown (Lathrop Grammar School Maintenance Supervisor), the well is used to Irrigate the grammar school and operates from 7 00 pm to 5 10 am SECOR arranged to sample the well on October 7, 2003 The well was ; sampled at 4 40 am (under supervision of Manteca Unified School District staff), near the end of the v well pumping cycle The water sample was collected from a spigot at the well head The sample was analyzed for total petroleum hydrocarbons calculated as gasoline (TPHg), benzene, toluene, r ethylbenzene, xylenes (BTEX compounds), and fuel oxygenates MtBE, EtBE, TAME, TBA, DIPE, EDB, 1,2-DCA, and ethanol by EPA Method 8260, single run All constituents were reported as not detected at or above the laboratory reporting limit Field notes and laboratory analytical report are included In Attachment B PUMPING WELL INFLUENCE STUDY On October 6, 2003, pressure transducers with built In data-loggers were installed In five groundwater monitoring wells (MW-11, MW-12, MW-13, MW-14 and MW-16) Each pressure transducer/data logger was programmed with the correct date and time, and to record water levels at 10-minute intervals over a 4-day monitoring period On October 10, 2003, the pressure transducers/data loggers were removed from the wells Field data sheets documenting transducer installation are included as Attachment C