Review of Trace Element Blank and Replicate Data Collected in Ground and Surface Water for the National Water-Quality Assessment Program, 1991–2002
By Lori E. Apodaca1, David K. Mueller2 and Michael T. Koterba3
Scientific Investigations Report 2006-5093, published 2006.

U.S. Department of the Interior
Dirk Kempthorne, Secretary

U.S. Geological Survey
Mark D. Myers, Director







National Water-Quality Assessment Program



The use of firm, trade, and brand names in this report is for identification purposes only and does not constitute endorsement by the U.S. Geological Survey.