Documentation for the Gridded Hourly Atrazine Emissions Data Set for the Lake211 Michigan Mass Balance Study. A Final Contract Report

摘要

In order to develop effective strategies for toxics management, the Great Lakes211u001eNational Program Office (GLNPO) of the United States Environmental Protection 211u001eAgency (U.S. EPA), in 1994, launched an ambitious five year program to conduct a 211u001emass balance study of selected toxic pollutants in Lake Michigan for the target 211u001eyear of 1995 (U.S. EPA, 1998). Three persistent organic pollutants (POPs) and one 211u001eheavy metal have been selected for the focus of the Lake Michigan Mass Balance 211u001e(LMMB) study; polychlorinated biphenyls (PCBs), trans-nonachlor, atrazine and 211u001emercury. Atrazine is a broadleaf herbicide typically applied to corn, sorghum, 211u001esugarcane, pastures, sweet corn, seed crops and sod (Gianessi and Puffer, 1991). 211u001eIn 1991, applications to corn and sorghum accounted for approximately 95% of the 211u001etotal atrazine useage in the United State (Gianessi and Puffer, 1991). Atrazine 211u001eis typically applied as a pre-emergent spray and/or a post-emergent spray 211u001ealthough it can also be incorporated into the soil prior to planting (USDA, 211u001e1995a). Peer reviewed literature suggests that atmospheric sources of atrazine 211u001emay be an important input of herbicide to the Lake Michigan system (Schottler and 211u001eEisenreich, 1997). The National Oceanic and Atmospheric Administration (NOAA) is 211u001ecollaborating with the LMMB study in its estimation of the atmospheric deposition 211u001eof atrazine to Lake Michigan.