National Water-Quality Assessment Program— Pesticides in the Trinity River Basin study unit, Texas, 1968-91

The Trinity River Basin National Water Quality Assessment (NAWQA) study-unit staff began assessment activities in 1991, and in 1992, undertook a retrospective review of existing data on pesticides. The main purpose of this review was to aid in the design of a pesticide-sampling network for the study unit. The review consisted of the compilation, screening, and analysis of available pesticide-sample information. In addition, important environmental factors, which influence the occurrence and distribution of pesticides in the study unit, were identified and compiled. A report of this review and analysis will be released in 1995 (Ulery and Brown, in press). This fact sheet provides a brief overview of significant findings.