By David K. Mueller, Jeffrey D. Martin, and Thomas J. Lopes

Abstract
The data-quality objectives of the National Water-Quality Assessment Program include estimating the extent to which contamination, matrix effects, and measurement variability affect interpretation of chemical analyses of surface-water samples. The quality-control samples used to make these estimates include field blanks, field matrix spikes, and replicates. This report describes the design for collection of these quality-control samples in National Water-Quality Assessment Program studies and the data management needed to properly identify these samples in the U.S. Geological Survey's national data base.

• Full Report in PDF format (0.6 mb)

U.S. Department of the Interior, U.S. Geological Survey Maintainer: Kerie Hitt (kjhitt@usgs.gov) Last update: 14:59:35 Fri 19 Jul 2002 Privacy Statement || Disclaimer || Accessibility URL: http://water.usgs.gov/nawqa/protocols/OFR97-223/