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Response Action Plan and Construction Contingency Plan June 10, 2016 Attachment C Former PIK Terminal, Roseville, MN 2.Area B –Southwest portion of the property. Primarily impacted with non- petroleum compounds in soil and groundwater. The northern approximately 190 feet of Area B included a portion of the parcels that were sold to Calyxt. Significant investigations on this portion of the area have identified only petroleum impacts. 3.Area C –Southeast portion of the property. Primarily impacted with petroleum compounds in soil and groundwater from two former underground storage tank basins (LEAK# 1326). Soil impacted with petroleum-impacts remaining beneath and around the former UST basins. Based on the New Brighton, Minnesota USGS topographic map, the surface elevation of the property ranges from approximately 910 feet above Mean Sea Level (MSL) on the south side of the property to 930 feet on the north side of the property. No surface water bodies are on the property, although Langton Lake is located less than 150 feet north of Area C. The 1992 Geologic Atlas of Ramsey County indicates that surficial geology in the vicinity of the property consists of sandy lake sediments with fine to medium grained sand, silt, and clay which is consistent with our field observations. Bedrock is indicated to consist of fine grained dolostone and limestone of the Platteville formation, underlain by thin, green sandy shale of the Glenwood Formation. The Platteville is possibly overlain in places by the Decorah Shale. The bedrock surface is expected to occur approximately 100 feet below ground surface (bgs). The perched water table (shallow groundwater) is estimated to range from approximately 10 to 20 feet deep. During the most recent investigations, groundwater was encountered at a depth of approximately 10 feet in the south portion of the property (Areas B and C). Four monitoring wells were recently installed on the property and preliminary measurements indicate groundwater flow is to the north-northeast which is consistent with investigations on adjoining properties. Based on recent borings completed in the glacial aquifer, the depth to the glacial drift aquifer is about 55 feet. The depth and gradient of the water table likely varies seasonally with changes in precipitation, and may change significantly over time in response to development, including impervious surfaces, storm water controls, and pumping wells (domestic, industrial, or irrigation). 1.3 Prior Investigations The larger PIK Terminal Site is listed on the following MPCA databases: Leaking Underground Storage Tank (LUST) – Leak#1326 (Closed) Voluntary Superfund – #SR387 (Active) 2