Laserfiche WebLink
16 February 1999 <br /> AGE-NC Project No 97-0290 <br /> Page 10 of 11 <br /> 45 RECEPTOR WELL SURVEY <br />' The City of Lodi Well No 2 is located approximately 550 feet north of the site Well No 4 is located <br /> Pp Y <br />' approximately 900 feet east of the site Well No 3 is located approximately 1450 feet south of the <br /> site Well Nos 3 and 4 are listed as off-line <br /> No additional wells were located within 2,000 feet of the subject property on the California <br /> Department of Water Resources database and the San Joaquin County Flood Control and Water <br /> Conservation District map <br /> r <br /> 5.0. SUMMARY AND CONCLUSIONS <br /> Based on the data collected from the site, AGE finds <br /> • The highest concentrations of petroleum hydrocarbons in soil were detected near the <br /> southeast portion of the site at depth intervals of 15 to 25 feet bsg and 35 to 50 feet bsg <br /> . (Figures 5 and 6) <br /> G Impacted soil at depth appears to be concentrated in a silt and clay layer between <br /> approximately 40 to 47 feet bsg <br /> • Lower concentrations of hydrocarbons were detected in borings B4, MW4 and B6 at depths <br /> of 35 to 60 feet bsg, corresponding to historical ground water levels <br /> I • A hard silt/clay layer appears to underlay the site at a depth of approximately 60 feet bsg <br /> This layer may act as a confining layer, preventing the deeper migration of contaminants at <br /> the site Thickness of the silt/clay unit has not been determined <br /> • Highly permeable soils encountered beneath the site could potentially promote vertical <br /> migration cif contaminants in the vadose zone and lateral migration of contaminants in <br />' ground water <br /> • Historical depth to ground water at the site has ranged from approximately 35 feet bsg in <br />' 1971 to 55 feet bsg in 1993 and 1996 Ground water is currently at a depth of approximately <br /> 44 feet bsg <br /> • One active municipal well is located approximately 550 feet north of the site Inactive <br /> municipal wells are located approximately 900 feet east and 1450 feet south of the site <br /> • Historic operation of nearby municipal wells may account for the deeper northerly and the <br /> Ieasterly migration of contaminants from the site <br /> iCurrent ground water flow at the site is toward the south Historical flow may have varied <br /> Advanced GeoEn%tronmental,Inc <br />