| Comments: |
No report was submitted during the reporting period. Additional sub-slab vapor samples were collected on October 23, 2018 in the bar and duplex to determine current PCE and TCE concentrations. The analytical results indicate PCE and TCE remain in the former dry cleaning machine area of the bar at concentrations in exceedance of their respective small commercial VRSLs. PCE and TCE were not present at concentrations in exceedance of their respective small commercial VRSLs in the former floor drain areas to the north and along the western elevation of the bar. PCE and TCE concentrations in exceedance of their respective residential VRSLs remain in the duplex. TCE is also present in the duplex at concentrations in exceedance of its small commercial VRSL. Based on these results, two (2) sub-slab depressurization systems will be required to mitigate the PCE and TCE impacted vapors. UEC is currently coordinating the configuration of the exterior portion of these systems with RMES. The below grade portion of the systems were installed during the renovation of the structure(s). The proposed exterior portion of the systems and maintenance etc. will be incorporated into letter reports summarizing the additional WDNR requested information outlined in the WDNRs July 3, 2018 written denial of the previously submitted revised RAP and NR 716 compliant SI.
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