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National Water-Quality Assessment (NAWQA) Study-Unit Investigations in the conterminous United States 1991-2001

January 1, 2006

This is a coverage of the boundaries and codes used for the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program Study-Unit investigations in the conterminous United States, excluding the High Plains Regional Ground-Water Study. The data set represents the areas studied during the first decade of the NAWQA Program, from 1991-2001 ("cycle 1").

Citation Information

Publication Year 2006
Title National Water-Quality Assessment (NAWQA) Study-Unit Investigations in the conterminous United States 1991-2001
DOI 10.3133/70046917
Authors K.J. Hitt, N. Nakagaki
Publication Type Report
Publication Subtype USGS Unnumbered Series
Index ID 70046917
Record Source USGS Publications Warehouse