SITE INFORMATION AND CORRESPONDENCE

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i 1117 Lone Palm Avenue, Suite 201 VATC Modesto,California 95351 209-579-2221 Fax:209-579-2225 AS 8 0 C I ATE 8 I N C. December 8,2008 54.28589.0001 Mr. James Barton California Regional Water Quality Control Board Central Valley Region 11020 Sun Center Drive,9200 Rancho Cordova, California 95670 Subject: Well Destruction and Installation Inside Existing Conductor Casing Workplan, J&L Market, 8125 El Dorado Street, French Camp, California Dear Mr. Barton: ATC Associates Inc. (ATC) has prepared this workplan, on behalf of J&L Market,describing proposed drilling activities to be conducted at the above referenced site (Figure 1). The purpose of this workplan is to describe procedures for destroying a 69-foot groundwater monitoring well (JLM21) that was installed inside 8.313-inch inside diameter steel conductor casing on November 10, 2008, and to install a replacement well inside the conductor casing following destruction on the initial well. The scope of work is described in detail in the following paragraphs. BACKGROUND INFORMATION Groundwater monitoring well JLM21 is a 2-inch diameter PVC well installed to approximately 69 feet below grade with approximately five feet of 0.010 inch slot screen. This well was installed on November 10, 2008, within a 8.313-inch inside diameter steel conductor casing that was previously installed to approximately 63 feet below grade.JLM21 was installed as part of subsurface investigation activities proposed in ATC's Revised Subsatface Investigation Workplan, dated August 14, 2008, and approved by the California Regional Water Quality Control Board in correspondence dated August 27, 2008.The location of this well is shown on Figure 2. i I During well development activities, a significant amount of fine-grained sediment and coarse-grained sand indicative of subsurface formation and well filter pack, respectively, were observed in water j purged from the well. A video camera inserted into the well showed the well to contain sediment. The total depth measured in the well was approximately 63 feet. Repeated attempts to remove the sand were unsuccessful. Consequently, this well was not properly developed and appears to be compromised. SCOPE OF WORK ATC proposes to destroy the compromised well by drilling with 8-inch hollow stein augers containing a steel plug. The augers will be advanced through the conductor casing to a depth of approximately 70 to 71 feet. The borehole will be reamed out and a replacement well will be installed inside the S:Tnvironmental\28589keplacemennrell wkpAd l ATC Associates Inc. '..