| Popis: |
Two roads on the Hanford Site, which had been treated during past Site operations with oil for dust suppression, were analyzed for potential polychlorinated biphenyl (PCB) contamination. The general locations of these roads are (1) off Washington State Route 240, north of Horn Rapids Dam, and (2) between the 200 East and 200 West areas, south of the 200 Area fire station. Each road had an intact crust of oil/tar on top of the underlying soil surface. A set of control samples were collected at an untreated soil site near the Prosser Barricade air sampling station. Samples were collected of the oil/tar surface crust, the soil immediately beneath the surface crust (0 - 3 cm below the crust), and a deeper soil sample (13 - 23 cm below the surface crust). Samples were collected at two locations on each road. The PCBs were extracted from the samples using a roller technique with methylene chloride, cleaned using column chromatography and high-pressure liquid chromatography, and analyzed by capillary gas chromatography using electron capture detection. The samples were analyzed for PCBs as the following technical mixtures: Aroclor 1242, Aroclor 1248, Aroclor 1254, and Aroclor 1260. All samples at all locations were less than the following detection limits: surface crust (41 ug/kg dry weight) and soil (2.1 ug/kg dry weight). These concentrations are below the U.S. Environmental Protection Agency (EPA) Region IX preliminary remediation goals for PCBs in residential soil (66 ug/kg) and well below the preliminary remediation goal for PCBs in industrial soil (340 ug/kg). |
