Laserfiche WebLink
Lisa Medina [EHJ <br /> From: Silva, Larry <Isilva@craworld.com> <br /> Sent: Wednesday, May 23, 2012 6:21 PM <br /> To: Lisa Medina [EHl <br /> Subject: 6131 Pacific Avenue, Stockton, CA <br /> Good Afternoon Ms.Medina, <br /> As requested,Conestoga-Rovers&Associates (CRA)has prepared this email to document our justification for <br /> installing two groundwater wells (one onsite and one offsite) in the"C" zone at the subject site instead of only <br /> one onsite groundwater well as approved by San Joaquin County Environmental Health Department <br /> (SJCEHD) on November 7,2011. Our justification is discussed below. <br /> Based on the horizontal extent of impact to groundwater in several of the groundwater zones at the site, <br /> impact to groundwater in the"C" zone has also likely migrated offsite. Itis not likely that one onsite <br /> groundwater well will provide sufficient data to define the horizontal extent of impact in groundwater in this <br /> zone. <br /> Considering that a second field investigation will likely be required if only one onsite groundwater well is <br /> installed and the substantially lower costs associated with installing a second groundwater well during the <br /> same investigation,it would be more cost effective to install two groundwater wells at the same time. This <br /> approach will not only reduce the cost to closure for this project,but the additional data will provide for a <br /> more comprehensive Conceptual Site Model. <br /> Regards, <br /> Larry J. Silva <br /> Conestoga-Rovers&Associates(CRA) <br /> 10969 Trade Center Drive,Suite 107 <br /> Rancho Cordova,California 95670 <br /> (916)889-8914 direct <br /> (916)919-7372 cell <br /> (916)889-8999 fax <br /> lsilva@craworld.com <br /> 1 <br />