Laserfiche WebLink
PUBLI �,HEALTH SERVICES <br /> N. <br /> SAN JOAQUIN COUNTY ,SO.p4UI <br /> r.� <br /> ENVIRONMENTAL HEALTH DIVISION <br /> Ernest M. Fujimoto, M.D., M.P.H., Acting Health Of;' % <br /> 304 E.Weber Ave., 3rd Floor a P. O. Box 388 • Stockton, CA 95 P.� <br /> 209/468-3420 r t)FORi+ <br /> ED RALSTON <br /> UNOCAL MAILED NOV 0 81995 <br /> 2000 CROW CANYON PLACE STE 400 <br /> SAN RAMON CA 94583-1367 <br /> Re: Unocal Bulk #0788 SITE CODE: 1597 <br /> 8203 West Eleventh Street <br /> Tracy CA 95376 <br /> San Joaquin County Public Health Services, Environmental Health Division (PHS/EHD) has completed <br /> review of the "Work Plan for Soil Vapor Extraction and Air Sparge Well Installations" dated April 27, 1995 <br /> and the "Well Permit Variance Request" dated October 6, 1995, both prepared by Pacific Environmental <br /> Group. PHS/EHD has the following comments for your consideration. <br /> The work plan included a proposal to install 25 air sparge wells and 18 soil vapor extraction (SVE) wells. <br /> These wells are to be installed using push point technology as described by Precision Sampling, Inc. <br /> PHS/EHD questioned the construction of these wells and the ability to perform to conventional standards. <br /> The use of push point installed vapor extraction wells was evaluated during the January 22, 1993 feasibility <br /> test which consisted of one extraction probe and two monitoring probes using a 2.5 horsepower <br /> regenerative blower. The extraction probe utilized a 2 standard cubic feet per minute flow rate and <br /> achieved an applied vacuum of 85 inches water with an estimated effective radius of influence of 14 feet. <br /> PHS/EHD grants the requested well permit variance for the installation of the air sparge and SVE wells. <br /> The upper two feet of all wells will be hand-augered to a 6 inch diameter and filled with concrete to the <br /> ground surface in order to minimize the potential of surface water infiltration. Furthermore, please note <br /> that wells must be covered with some type of approved locking encasement. <br /> Please note that PHS/EHD will require these wells to be destroyed by over-drilling once the site has been <br /> sufficiently remediated, based on soil and groundwater confirmation sampling, to warrant closure. A permit <br /> application for well installation should be submitted along with an $89. permit fee. Following permit <br /> issuance, please contact PHS/EHD at least 48 hours in advance to schedule an inspection of the proposed <br /> field activities. Also, submit a copy of the San Joaquin Valley Unified Air Pollution Control District's permit <br /> to construct. <br /> If you have any questions or to schedule a site inspection, please contact Mary Meays at(209)468-0337. <br /> Donna Heran, REHS, Director <br /> Environmental Health Division <br /> Mary Meays, Senior REHS Diane M. Hinson, REHS <br /> Site Mitigation Unit Supervisor <br /> MM/8203WELE <br /> cc: Elizabeth Thayer, CVRWQCB <br /> cc: Wendy Cohen, CVRWQCB <br /> cc: Joseph Muzzio, Pacific Environmental <br /> A Division of San Joaquin County Health Care Services <br />