The aquifer underlies 1,260,000 acres (510,000 hectares) of land in east-central Illinois and spans 15 counties (Panno and Korab, 2000).
[citation needed] An estimated 100,000,000 US gallons (380,000 kL) per day of groundwater is pumped from the aquifer to supply municipal, agricultural, commercial, industrial, and rural domestic users (Larson et al., 2003).
Approximately 45% of the water withdrawn is consumed by the public, 29% by industry, and 18% by commercial users (Panno and Korab, 2000).
[citation needed] The water quality in the Mahomet Aquifer is high in dissolved minerals and iron, which is typical of all groundwater.
Concentrations can range from 20 to 70 parts per billion (ppb), which exceeds the new standard adopted by the U.S. Environmental Protection Agency (Panno and Korab, 2000).