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<br /> N7onitoring Well Destruction Work Plan
<br /> Raymond Investment Corporation
<br /> November 20,2012
<br /> Page 2
<br /> MW-3 be properly destroyed and a replacement well (MW-3R) be installed approximately ten feet south
<br /> of MW-3. In a letter dated October 21, 2004, the SJCEHD approved the destruction of MW-3 and the
<br /> installation of MW-3R. Monitoring well MW-3 was properly destroyed and MW-3R installed on October,
<br /> 26, 2004. All field and analytical activities involved in the installation, development, and sampling of
<br /> monitoring wells MW-1, MW-2, and MW-3R and the destruction of monitoring well MW-3R are
<br /> described in Condor's Monitoring Well Installation Report, dated December 15, 2004.
<br /> 1•� Quarterly monitoring events began in the fourth quarter 2004. The groundwater elevation in the
<br /> monitoring wells has ranged from approximately -13.5 to -21.0 feet above mean sea level (ams]} or 29.5
<br /> to 37.5 feet bgs. The general groundwater gradient for the Site has been approximately 0.005 ft/ft to the
<br /> east-northeast, or 60 degrees east from true north.
<br /> Analytical constituents have rarely been detected at or above the laboratory reported detection limits in
<br /> the groundwater samples collected from monitoring wells MW-1, MW-2, and MW-3R. On May 4, 2005,
<br /> TPH-G and TEPH-D were detected in the groundwater sample collected from MW-1 at concentrations of
<br /> 170 micrograms per liter (µg/L) and 110 µglL, respectively. On August 16, 2005, TPH-G and TEPH-D
<br /> were detected in MW-2 at 92 µg/]L and 82 µg/L, respectively. No other analytical constituents were
<br /> detected at or above the laboratory reported detection limits in the samples collected from those wells on
<br /> those dates.
<br /> MW-4 was installed on August 29, 2006. Soil borings were made on September 7, 8, and 28, 2006. The
<br /> installation and investigation activities were documented in the report titled Additional Soil and
<br /> Groundwater Investigation Report and Third Quarter 2006 Monitoring Report, dated January 2, 2007.
<br /> Groundwater monitoring continued with some modifications. The report titled Site Conceptual Model
<br /> 2008, dated October 31, 2008, summarized data that had been collected regarding the Site to date and
<br /> 1� clarified existing data gaps. Soil samples were collected from borings, SB-12, SB-13, and S13-14,
<br /> monitoring wells MW-4D, MW-5, and MW-6 were installed, and soil vapor monitoring wells SV-4, SV-
<br /> 5, and SV-6 were installed in May and June 2010. Condor prepared the Monitoring Well, Soil Vapor
<br /> Well, and Soil Boring Installation Report to document the field activities and laboratory analytical results.
<br /> Monitoring well MW-7 was installed and sampled in April 2011. Condor prepared the Monitoring Well
<br /> MW-7 Installation and Groundwater Sampling Report, dated June 6, 2011 to document the installation
<br /> al and laboratory analytical results. Groundwater monitoring continued until August 1, 2011.
<br /> Condor prepared the Remediation Feasibility Report, dated August 25, 2011. The State Water Resources
<br /> Control Board Cleanup Fund (SWRCBCF) letter dated August 18, 2011 indicated that they had
<br /> conducted a five year review and recommended that the SJCEHD consider the site for closure. The
<br /> SJCEHD letter dated December 9, 2011 directed that a site closure report be prepared. Condor prepared
<br /> the No Further Action Request, dated April 6, 2012. The SJCEHD submitted the Case Closure Summary
<br /> dated September 13, 2012 to the Central Valley Regional Water Quality Control Board (CVRWQCB).
<br /> The CVRWQCB letter, dated October 11, 2012, indicated that they concurred with the recommendation
<br /> for closure. The SJCEHD letter, dated October 18, 2012, directed that a work plan for the destruction of
<br /> the monitoring wells at the Site be prepared.
<br /> 3.0 SITE PREPARATION
<br /> A well destruction permit will be obtained from the SJCEHD. Prior to initiating the fieldwork, the well
<br /> locations will be marked with white paint and Underground Service Alert (USA) will be notified at least
<br /> 48 hours in advance of the fieldwork to locate and identify underground utilities in the vicinity of the
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<br /> W CONDOR
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