Dewey County, SD

ZIP 57601

In ZIP 57601, 4 of the 12 things we check have at least one part graded D or F.

• Drinking water: Mobridge meets every EPA legal limit; 4 contaminants are above health goals, led by lithium at 5.3× the USGS health-based screening level.
• Closer to Superfund sites than 0% of U.S. neighborhoods, with no listed site within 10 miles of its center.
• Largest share of modeled toxic air from industry: Dairi Concepts (100%), mostly polycyclic aromatic compounds.
• Fine particles (PM2.5) average 5.8 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 116,113 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 57601

• Superfund sites nearbyA
• Factories and industrial sitesA
• Oil and gas wellsA
• Parks and nature nearbyA to C
• Air qualityA
• Drinking water qualityA to C
• Pesticide useF
• Neighborhood health statusC to F
• Past wildfire impactsA
• Past flood impactsA
• Noise levelsA to D
• Radiation signalsC to F

Based on 4 census tracts · compiled October 25, 2026 · how each grade works and its sources

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