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Project Number 1804BK54 April 11,2013 1.0 INTRODUCTION This Site Decommissioning Workplan is submitted pursuant to a request from the State of California Regional Water Quality Control Board - Central Valley Region, Sacramento Main Office 9CRWQCB) (oral communication April 8, 2013). 1.1 Site Description The Former Busy Bee facility is located at 40 North Main Street, Lodi, California (see Figure 2). 1.2 Site History Dry cleaning equipment was reported as being installed at the Site in 1985. During operation of the facility, tetrachloroethene (PCE) (a.k.a. tetrachloroethylene) was recovered from dry cleaning process wastewater and recycled. Some PCE was also routinely discharged in the wastewater during normal operations, but there are indications that PCE-laden discharges into the sanitary sewer ceased in the early 1990s (or possibly earlier). Dry cleaning operations ceased abruptly after a fire destroyed the equipment and the building in 1996. Site History has been extensively documented in previous status reports. From 1989 through 2004, extensive Site Investigation activities were conducted to evaluate the degree and size of PCE-impact to the subsurface at and near the Site. Groundwater monitoring commenced in 2003. In 2005 two (2) remediation systems were installed and in 2006, the systems were tested (systems' pilot testing). From 2007 through mid-2008 additional investigations were performed and the groundwater monitoring program was tweaked. During that time, remediation system permitting was also carried out. In August 2008, site cleanup commenced with startup of the two remediation systems. In June 2012, the remediation systems were shut down as it was no longer cost-effective to operate the systems due to reduction of contaminants to very low concentrations. On October 24, 2012, a remediation status review meeting for the Site was held at the CRWQCB offices in Rancho Cordova, California (CRWQCB). At the meeting, it was concluded that the current soil vapor extraction and groundwater air sparging system had effectively remediated the Site. At the same time, the concentrations of tetrachloroethylene (PCE) in groundwater at site monitoring wells had declined to low concentrations with only a few wells having dissolved-phase PCE at concentrations greater than the State Maximum Contaminant Level of 5 micrograms per liter (µg/L). In addition, site monitoring data indicated that natural degradation was occurring; however, the concentration of PCE at monitoring well MW-7BB (45.9 µg/L) in the Third Quarter 2012 (see Table 3) was the only impediment to Site Closure. As such, and at the request of the CRWQCB, E2C Remediation (E2C) submitted a Batch Pumping Workplan to address this concern on October 31, 2013. The CRWQCB reviewed and approved the Workplan by letter on November 30, 2012 with the caveat that well EX-1 BB be added to the program. The purpose of the Batch Pumping was to evaluate whether the residual concentrations of PCE in groundwater at EX-11313 and MW-7BB consisted of localized pockets of contamination, or were indicative of a more widespread problem. E2C conducted the Batch Pumping program during the period of December 19, 2012 through February 20, 2013. E2C Remediation 1