The industries employed an estimated 1,262 people. Most of the businesses in Delaware County purchase their water from a PWS or obtain their water from a private supply not requiring a permit. There is one water use permit for industry in Delaware County. There is no power production in Delaware County. Mining Water Use Mining in Delaware County consists of sand and gravel extraction.
Activity varies from year to year based upon construction needs.
Seven water permits were issued for mining in the county. The State-Wide Rural Well Water Survey completed in 1989 indicates the following quality results for private well water, shown in Table 3, for the east hydrogeologic region in which Delaware County is located. The Iowa State-Wide Rural Well Water Survey, 1990. The UHL's test results for the county also show that in an average year 30.2 percent of wells tested for nitrates exceeded the recommended maximum. These test results are based on non-random samples.