ARCHIVED REPORTS_XR0005412 - Laserfiche WebLink

Home Browse Search

Ate. HORIZON ENVIRONMENTAL INC. Specialists in Site Assessment,Remedial Testing,Design and Operation January 22, 1999 Mr. Joe Aldridge Ultramar Inc. 525 West Third Street Hanford, California 93230 Subject: Quarterly Groundwater Monitoring Report Fourth Quarter - 1998 Beacon Station No. 474 3443 East Main Street, Stockton, California Mr. Aldridge: Horizon Environmental Inc. (Horizon) has prepared this Quarterly Groundwater Monitoring Report which presents results for the fourth quarter 1998 monitoring activity for the above- referenced site (Figure 1). There are currently nine groundwater-monitoring wells (MW-1 through MW-9) and six vapor extraction wells (VW-1 through VW-6) associated with this site. All of the wells are located onsite, except for wells MW-4 and MW-5, which are offsite groundwater monitoring wells (Figure 2). Groundwater Monitoring Depth-to-groundwater measurements were obtained from all the monitoring wells by Doulos Environmental Company (Doulos) on December 30, 1998 (see Table 1). Static groundwater levels were reported as being measured from the top-of-casing (T.O.C.) of each well (with water present) and recorded to the nearest 0.01-foot. Water level measurements were subtracted from reference elevations as reported by previous consultants to obtain water elevations, as listed in Table 1. Ultramar Inc. (Ultramar) Field Procedures are presented as Attachment A with this report. Doulos Field Data Sheets are included as Attachment B. Historical groundwater data as reported by previous consultants is included as Attachment D. Groundwater samples were collected from monitoring wells MW-5 through MW-9 and vapor extraction wells VW-1 and VW-4. Groundwater samples were not collected from monitoring wells MW-1, MW-2 and MW-3 because the screened interval for each of these wells is submerged, and each of these wells is located adjacent to wells MW-6, MW-8 and MW-9. A groundwater sample was not collected from monitoring well MW-4 because the wellhead was covered by a parked vehicle. Collected samples were submitted under chain- of-custody (COC) to Kiff Analytical (Kiff), a California Department of Health Services- certified analytical laboratory (ELAN No. 2236) located in Davis, California. Groundwater samples were analyzed for Total Petroleum Hydrocarbons as gasoline (TPHg) utilizing EPA 5011 Golden Foothill Parkway,Suite 7 • EI Dorado Hills,CA 95762 . (916)939-2170 • FAX(916)939-2172 PO.Box 5283 • Bakersfield,CA 93388 . (805)589-8389 . FAX(805)589-1456