Laserfiche WebLink
FY 17 <br />Cleanup - 6 <br />investigations determined that at least one of the two USTs had leaked and released <br />product to soil and groundwater. The Minnesota Pollution Control Agency (“MPCA”) <br />closed the leak site in 2013, but contamination may have remained after closure. <br />20. Summary of Contamination Information: <br /> <br />A. Provide a concise description of the identified contamination and proposed RAP. The <br />description should include the occurrence of the contamination (i.e., are there distinct <br />areas of contamination or is contamination widely disseminated across the site? Is the <br />contamination at the surface or at depth? <br /> <br />Soil impacts above applicable MPCA criteria were identified in two distinct Hot Spot <br />locations, as shown on attached figures. The larger of the two Hot Spots is below the footprint <br />of a future residential building. The smaller of the two Hot Spots is adjacent to a residential <br />building in a future greenspace area. Impacts to soil vapor above MPCA action limits were <br />identified in two sampling locations, LGP-1 and SV-2, as shown on attached figures. <br /> <br />The following response actions (“RAs”) will be conducted at the property in according to the <br />MPCA-approved Voluntary Response Action Plan and Voluntary Response Action Plan <br />Addendum: <br /> <br /> Soil with petroleum impacts above the cleanup goal (MPCA criteria for unregulated <br />excess fill) will be transported off-site to a permitted landfill from the following areas (as <br />shown on attached figures): <br />o RA Area 1: Soil located near a former underground storage tank in the northwest <br />portion of the property. Soil will be excavated as determined during RA <br />implementation activities to a maximum depth of 12 feet. <br />o RA Area 2: Soil located in the southwest corner of the property at LGP-2. Soil <br />will be excavated to a depth of 2 feet. <br />The quantity of contaminated soil is estimated at approximately 2,000 cubic yards. <br /> <br /> Excavated soil meeting cleanup goals and the definition of unregulated fill will be reused <br />onsite or offsite whenever possible. <br /> <br /> Excavation dewatering procedures will be implemented during RA activities and <br />construction. Because the groundwater contains low level concentrations of VOCs, <br />proper permitting, sampling and reporting for discharge will be required. It is likely <br />dewatering will be necessary for construction. <br /> <br /> Install an active venting system in southern-most proposed building, nearest to the two <br />investigation locations where impacts to soil vapor exceeded applicable MPCA action <br />58