7/1/2005 - 6/30/2007
- George Kraft, UW-Stevens Point
- Bryant Browne, UW-Stevens Point
The leakage of nitrate and pesticide residues to groundwater increased greatly with the large increase in fertilizer and pesticide use that began about 1960 and did not level until the 1990s. The resulting groundwater pollution has degraded drinking water resources and has implications for aquatic ecosystem health. Since the increase in pollutant leakage is recent compared with typical groundwater residence times, modern aquifer pollutant loads (pollutant mass in aquifer storage) may not be in equilibrium with modern pollutant leakage. Absent an equilibrium, nitrate and pesticide pollutants will continue to penetrate deeper into the aquifers of agricultural landscapes, thus increasing loads and exports. Especially given that nitrate and pesticide residues are widespread and mostly uncontrolled groundwater pollutants, there is a strong need to understand how present pollutant conditions developed and what the future trends will be. This proposed study will examine whether nitrate and pesticide aquifer loads (mass of pollutant in aquifer storage) are increasing or are in equilibrium in the aquifer of the heavily-agricultural part of the Northern Mississippi Valley Loess Hills (NMVLH) Area in southwest Wisconsin.