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Ms. Margaret Knowlton Pag~: 2 Dee,ember 12, 1997 The Site consists of approximately 34 acres of land divided into three parcels: a northern parcel consisting of 8 acres of vacant land; a middle parcel consisting of 12 acres of wooded vacant land; and a southern parcel consisting of 14 one-acre residential lots, 13 of which supported homes and associated residential structures. A number of the homes and structures were demolished, and the remainder relocated, in August and September of 1997. The northern parcel contained a farmhouse, bam, and fields from 1940 to 1959, when the house and bam were demolished. A trucking facility consisting of a warehouse, garage, and office occupied the Site from 1959 until approximately 1981. In 1982, the buildings were demolished; sincl~ this time, the northern parcel has been vacant. Historical information indicates that the middle parcel has always been vacant, although it is evident that filling and grading have occurred and debris piles are present in several areas. The southern parcel has consisted of residential lots since 1941. Prior to 1941, this parcel was wooded and had paths or roads leading from Highway 36 and Cleveland Avenue. A number of investigations of the Site have been performed over time; only findings pertinent to the determination made in this letter are detailed here. In 1989, six soil borings were placed at the Site, and soil samples along with two ground water grab samples were analyzed. Arsenic was the only compound detected above MPCA soil screening values, at a concentration of 17 parts per million, from a depth of five feet at TH-4. Additionally, several metals were detel:ted over the Minnesota Department of Health's (MDH) Health Risk Limits (HRLs) in the ground water samples, but these results are questionable since they were samples collected from open boreholes and likely contained sediment. A subsequent, filtered ground water sample colle:cted in the same area did not confirm these exceedances. In 1997, surface soil samples, soil borings, and grab ground water samples were collected and . seven monitoring wells were installed at the Site. Polynuclear aromatic hydrocarbons (PAHs) and arsenic were detected in soil above soil screening values in sample PI and composite stockpile sample P3, respectively. Trichloroethene (TCE) and tetrachloroethene (PCE) were deteeted above HRLs in a ground water sample from a soil boring. Additionally, TCE was deteeted just below and at the HRL in perched water samples from a monitoring well near the northern Site boundary, and PCE was detected at the HRL in a deep monitoring well at the southern Site boundary. Response action activities at the Site were implemented during August, September, and October 1997. Soil response actions consisted of removal of surface soil stockpiles contaminated with arsenic (at location P-3) and PAHs (P-l), and excavation of arsenic contaminated soil at boring TH-4. Confirmation samples from the base and sidewalls of the excavation at TH-4 indicated levels of arsenic which were non-detectable or below MPCA scree:ning levels. All contaminated soil was transported to a disposal facility.