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07/13/2016 C&S Cleaners Site Work Plan 2013. Based on the results of those data, ARCADIS requested closure of the Site in a memorandum e- mail addressed to the CVRWQCB and dated December 18, 2013 (ARCADIS 2013).The CVRWQCB did not concur with site closure, citing concerns that the post remediation data did not demonstrate a decreasing trend (e-mail from Roberto Cervantes to Scott Seyfried dated January 15, 2014).To address that concern,ARCADIS collected two additional rounds of post-remedy data during July and November 2014. Meeting with RWQCB to Discuss Site Closure February 2015 Representatives of Robinhood Plaza met with RWQCB staff on February 15, 2015 to discuss post- remedial monitoring data collected up to November 2014 and potential closure of the site. During that meeting, it was agreed that the existing set of data indicated that the concentrations of VOCs in soil gas did not exhibit an increasing trend, and instead indicated that concentrations were decreasing. However, based on the magnitude of the concentrations detected and the nature of available trend data,the RWQCB did not agree to make an NFA determination for the Site. During that meeting, the RWQCB indicated that a NFA determination could be made if results from an additional round of data confirmed a decreasing trend in the data, provided that Robinhood seal the floor beneath the dry cleaning operation as mitigation measure. Results of Most Recent Monitoring Event In response to that meeting, an additional round of soil gas monitoring was completed on February 24, 2015, and provided to the RWQCB in a report dated May 15, 2015 (ARCADIS 2015).As presented in the May 15 report, concentrations of PCE measured in soil gas samples collected during the February monitoring event confirmed a decreasing trend for concentrations of PCE in soil gas beneath the Site. A summary of soil gas monitoring data collected from the Site is provided in Table 1.The decreasing trend was expected given the source of PCE was identified and removed,the remaining source area is relatively small (on the order of 5 feet by 5 feet), and the length of time that has elapsed since the SVE remedy was discontinued (February 2011).TCE concentrations were not detected above the laboratory reporting limits. The May 15 report requested that the RWQCB grant NFA status for the site based on following rationale. • The source for PCE detected at this Site (dry-cleaning solution) has been identified and removed. • The Site has been adequately characterized, including adequate identification and characterization of sources, pathways, and potential receptors. • The concentration of PCE detected in soil and soil gas beneath the Site does not represent a threat to underlying groundwater quality. • The concentrations of PCE remaining in soil gas directly beneath the dry-cleaning facility are on average below the commercial screening level and do not present a risk to human health or the environment. • Given the limited timeframe anticipated for remaining PCE concentrations to reach residential clean- up goals, no additional actions are necessary. Page 2 of 5 Terraphase Engineering Inc.