Laserfiche WebLink
.� California Regional Water Quality Control Board ;t <br /> Central Valley Region <br /> v Karl E.Longley,ScD,P.E.,Chair <br /> Linda S.Adams Arnold <br /> SecSacramento Office <br /> Environmentetaryforal <br /> Schwarunegger <br /> Environmental 11020 Sun Center Drive#200,Rancho Cordova,California 95670-6114 Governor <br /> Protection Phone(916)464-3291•FAX(916)4644645 <br /> hap://www.waterbmrds.ca.gov/centralvalley <br /> ' 15 August 2008 <br /> Mr. Matt Gabris <br /> Sara Lee Bakery Group, Inc <br /> 3500 Lacey Rd. <br /> Downers Grove, IL 60515 <br /> ' DOCUMENT REVIEW, FORMER COLUMBO/TOSCANA BAKERIES, 1444 S. LINCOLN <br /> STREET, STOCKTON, SAN JOAQUIN COUNTY(REGIONAL BOARD CASE#390825) <br /> ' 1 reviewed the Sara Lee Bakery Group, Inc. (Sara Lee) Subsurface Investigation Report <br /> (Report), received 1 August 2008 from your consultant PSC Environmental Services Inc. <br /> (PSC). Prior to the Report, site investigations for the former underground storage tanks <br /> ' (USTs) focused on vertical definition in the USTs area and on the second aquifer (A zone) <br /> outside of the USTs area. The Report documents the April 2008 advancement of seven of <br /> eight approved direct push borings (CPT-M4 through CPT-M10, enclosed Figure 3) for vertical <br /> ' and lateral delineation of petroleum hydrocarbons in soil and groundwater. The eighth boring <br /> could not be completed due to the limited vertical access to the building. <br /> Depth to water varies from 18 to 20' below ground surface (bgs), at the site. The Report <br /> designates the first water aquifer (less than 37' bgs) as the Shallow zone, and states that <br /> groundwater may be perched in that zone. <br /> ' Eight direct push borings incorporated: <br /> • Membrane Interface Probe (MIP) logging to map the vertical distribution of total <br /> ' petroleum hydrocarbons with <br /> • Cone Penetrometer Test (CPT) logging of Iithology to a target depth of 125' bgs, and <br /> • collection of one confirmation soil sample core per boring at maximum depth with <br /> • two or three grab groundwater samples from zones A (37' to 57' bgs), B (70' to 90' bgs), <br /> and C (102' to 122' bgs) using a HydropunchTM sampler. <br /> ' The data were depicted in three geologic cross sections (enclosed Figures 5 through 7) to <br /> show the Iithology and distribution of soil contamination and groundwater pollution. A map <br /> view of the site illustrates the lines of the cross sections (enclosed Figure 4). <br /> ' Six confirmation soil sample results were non-detect for petroleum hydrocarbons, although the <br /> MIP data (enclosed Table 1) revealed significant contaminant concentrations (quantified as <br /> ' total petroleum hydrocarbons, or TPH) from 5' to 10' above total depth. The Reportstated drill <br /> rig refusal occurred for CPT-M8 (USTs area) at a total depth of 85' bgs without collecting a <br /> confirmation soil sample. <br /> California Environmental Protection Agency <br /> 0 Recycled Paper <br />