Summary

Description

A wood treatment facility located on YavapaiPrescott Indian Tribe land near Prescott, Arizona released pentachlorophenol PCP, arsenic, and chromium into the environment from 19611985. We sampled sediment, water, fish, crayfish, eggs, tadpoles, and frogs for trace elements, organochlorine insecticides, polyaromatic hydrocarbons, total polychlorinated biphenyls, dioxins, and furans. Levels of arsenic, chromium, copper, and nickel remained elevated in sediment samples just below Slaughterhouse Gulch, which empties into Granite Creek just below the wood treatment facility. Crayfish are bioaccumulating mercury and selenium in Granite Creek. Granite Creek fish were highly contaminated with arsenic. Although copper was elevated in fish, concentrations were not high enough to exceed toxicity thresholds. Chromium contamination in fish was also evident, although the significance of the chromium concentrations remains unclear. High mercury concentrations were found in fish in Granite Creek and Watson Lake that could affect sensitive fisheating predatory birds. Fish pentachlorophenol residues were lower than suggested regulatory guidelines. Only three dioxins and furans were detected in fish samples. Currently, soils from the onsite pond and work area are being bioremediated and, as soon as PCP levels reach Arizona nonresidential soil remediation levels, the site will be recontoured and reopened to the tribe.