Laserfiche WebLink
PUBLIe HEAL'T'H SAVICES �gRAK!y, <br /> so� <br /> SAN JOAQUIN COUNTY <br /> ENVIRONMENTAL HEALTH DIVISION :< <br /> Karen Furst, M.D., M.P.H., Health Officer <br /> 304 East Weber Avenue, Third Floor • Stockton, CA 95202 <br /> 209/468-3420 <br /> 'JAN 2 8 2002 <br /> Mike Wallace Mr. Jeffery Setness <br /> City of Stockton Redevelopment 4568 Feather River Dr <br /> 305 North E1 Dorado, Suite 200 Suite A <br /> Stockton, CA 95202 Stockton, CA 95219-6508 <br /> RE: FORMER CHASE CHEVROLET FACILITY <br /> 424 VAN BUREN <br /> STOCKTON,CA 95201 <br /> San Joaquin County Environmental Health Department(EHD) has reviewed the Ground Water <br /> Extraction Feasibility Test Report(the report) dated December 10,2001 prepared by Advanced <br /> GeoEnvironmental,Inc. (AGE). The report documented the groundwater extraction feasibility test <br /> conducted at the above-referenced site in August,2001. AGE calculated a transmissivity value of <br /> 1,120 ftz/day,storativity value of 0.099 using the Jacob straight-line method,hydraulic conductivity <br /> of 0.142 cm/s,and a radius of influence of groundwater extraction of 160 feet. AGE recommended <br /> installing a ground water pump-and-treat (PAT) system to augment the existing soil vapor extraction <br /> remediation system on site. <br /> EHD does not recommend installing a PAT system at this time due to insufficient information. <br /> The effectiveness of PAT is highly dependent on the type of contaminants and the soil physical <br /> characteristics of the aquifer. When the values of sorption and the retardation factor of the <br /> chemicals being removed are high, the length of active treatment could be very long. (Groundwater <br /> Pollution Primer,Virginia Tech, 1996). Protracted treatment could result in large volume of <br /> extracted contaminated groundwater that required disposal,which could significantly drive up the <br /> cost of the dean up. Furthermore, clean up goals are rarely met using PAT(Princeton Groundwater <br /> Pollution and Hydrology Course,Robert Cleary,2001). Typically,PAT is not a very time/cost- <br /> effective method in mass removal and aquifer remediation. <br /> EHD recommends AGE evaluate other strategies such as additional soil vapor extraction (SVE) and <br /> air sparging(AS)wells to address where the existing horizontal SVE wells have demonstrated to be <br /> ineffective,an additional SVE/AS system at the north side of the site,or the technology of ozone <br /> injection. <br /> If you have any questions contact Jeffery Wong at(209)468-0335. <br /> Donna Heran,RENS,Director <br /> Environm mal Health Division <br /> t <br /> J fret' ong, Senior REHS Margaret agorio,REHS <br /> LOP/Site Mitigation Unit IV Supervisor <br /> C: Advanced GeoEnvironmental,Inc.—Paul Dotsun <br /> C: RWQCB,Central Valley Region—Marty Hartzell <br /> A Division of San Joaquin County Health Care Services <br />