The industries employed an estimated 1,549 people. Most of the businesses in Hardin County purchase their water from a PWS or obtain their water from a private supply not requiring a permit. There are three water use permits for industry in Hardin County. There are no power production in Hardin County. Mining Water Use Mining in Hardin County consists of sand and gravel extraction.
Activity varies from year to year based upon construction needs.
Six water permits were issued for mining in the county. The Iowa State-Wide Rural Well Water Survey, 1990. The UHL's test results for the county also show that in an average year, 2.0 percent of wells tested for nitrates exceeded the recommended maximum. These test results are based on non-random samples. The University of Iowa Hygienic Laboratory, Private Well Water Quality, 1990-1994.