Laserfiche WebLink
Metadata
Document management portal powered by Laserfiche WebLink 9 © 1998-2015 Laserfiche. All rights reserved.
' Bank of Stockton Page 2 <br /> BofS (Cuter)-Preliminary Soil and Groundwater Investigation <br /> Project No 102 2 <br /> April 8, 1997 <br />' a result of the discovery, Geological Technics Inc conducted a review of public files in order <br /> to gain a better understanding of the past use of the Property The County Assessor's record <br /> for the Property was examined and documentation was found which revealed the existence of <br />' the former"Oil Supply" Building and at least one associated gasoline UST, several ASTs and <br /> a dispenser island which were situated 40 to 50 feet from the domestic water well <br />' To further investigate the former "Oil Supply" facility, Geological Technics Inc installed <br /> five 10-foot deep hand augered soil bonngs Soil samples were collected and tested from <br />' each of the borings The results of the borings and sampling suggest the former gasoline tank <br /> had been removed at some unknown time and the pit was back filled with soil Beneath the <br /> confines of the original tank pit, the soil was found to contain significant levels of gasoline <br />' range petroleum hydrocarbons (up to several thousand ppm TPH-G) One of the borings was <br /> installed in the area of the former dispenser island and several feet north of the UST pit Soil <br /> samples collected from this boring were found to contain diesel contamination which <br />' indicates the piping associated with the diesel pump may also have leaked <br /> 1.2 Scope of Work <br />' In order to begin the site characterization related to the gasoline and diesel fuel release, the <br /> following work was proposed, and then performed <br /> I A BK-81 hollow stem auger drilling ng, owned and operated by V&W Drilling Co (C- <br /> 57 4710678), was used to drill a total of 8 soil borings to a depth sufficient to penetrate <br /> the capillary fringe zone at about 35 feet The borings were logged and soil samples <br /> were collected for laboratory analysis to help define the lateral and vertical extent of <br />' petroleum hydrocarbons in the vadose zone and near the top of the saturated zone The <br /> boring locations were chosen with the intent of investigating hydrocarbon impact in <br /> the area in the immediate vicinity of the former gasoline UST, the domestic water well, <br />' and in the suspected down-gradient direction of groundwater flow <br /> 2 During the course of drilling the 8 originally proposed borings, gasoline contamination <br />' was found to be more widespread than had originally been supposed In an attempt to <br /> help define the extreme lateral limits of the gasoline plume, a decision was made in the <br /> field to add a 9`i' boring to the scope of work This was done with the knowledge of the <br />' LOP representative, Mr Harlan Knoll <br /> 3 The domestic water well in which the existence of gasoline impacted groundwater had <br />' first been discovered from this release was abandoned <br /> 4 The subject Property is the site of releases from two separate tank installations A total <br /> of 5 groundwater monitoring wells had been installed on the southerly part of the <br /> Property These wells were related to the investigation of a release from other tanks on <br /> 2937 Veneman Ave ,#B240 Geo-Phase Environmental Inc Phone (209) 569-0293 <br /> Modesto, CA 95356 Fax (209) 569-0293 <br /> 1 <br />