U.s. Department of the Interior

Quality-assurance Data for Routine Water Analyses by the U.s. Geological Survey Laboratory in Troy, New York? July 2003 Through June 2005 U.s. Department of the Interior

The laboratory for analysis of low-ionic-strength water at the U. S. Geological Survey (USGS) Water Science Center in Troy, N. Y., analyzes samples collected by USGS projects throughout the Northeast. The laboratory?s quality-assurance program is based on internal and interlaboratory quality-assurance samples and quality-control procedures that were developed to ensure proper sample collection, processing, and analysis. The quality-assurance and quality-control data were stored in the laboratory?s Lab Master data-management system, which provides efficient review, compilation, and plotting of data. This report presents and discusses results of quality-assurance and quality control samples analyzed from July 2003 through June 2005.