Evaluation of Quality-Assurance/Quality-Control Data Collected by the U.S. Geological Survey from Wells and Springs between the Southern Boundary of the Idaho National Engineering and Environmental Laboratory and the Hagerman Area, Idaho, 1989 through 1995

摘要

The U.S. Geological (USGS) and the Idaho Department of Water Resources, in cooperation with the U.S. Department of Energy, collected and analyzed water samples to monitor the water quality of the Snake River Plain aquifer from the southern boundary of the Idaho National Engineering and Environmental Laboratory to the Hagerman area, Idaho. Concurrently, replicate samples and blank samples were collected and analyzed as part of the quality-assurance/quality-control program. Samples were analyzed from inorganic constituents, gross radioactivity and radionuclides, organic constituents, and stable isotopes. To evaluate the precision of field and laboratory methods, analytical results of the water-quality and replicate samples were compared statistically for equivalence on the basis of the precision associated with each result. Statistical comparisons of the data indicated that 95 percent of the results of the replicate pairs were equivalent. Blank-sample analytical results indicated th at the inorganic blank water and volatile organic compound blank water from the USGS National Water Quality Laboratory and the distilled water from the Idaho Department of Water Resources were suitable for blanks; blank water from other sources was not. Equipment-blank analytical results were evaluated to determine if a bias had been introduced and possible sources of bias. Most equipment blanks were analyzed for trace elements and volatile organic compounds; chloroform was found in one equipment blank. Two of the equipment blanks were prepared after collection and analyses of the water-quality samples to determine whether contamination had been introduced during the sampling process. Results of one blank indicated that a hose used to divert water away from pumps and electrical equipment had contaminated the samples with some volatile organic compounds. Results of the other equipment blank, from the apparatus used to filter dissolved organic carbon samples, indicated that the filtering apparatus did not affect water-quality samples.