Jefferson County, MO

ZIP 63020

In ZIP 63020, 7 of the 12 things we check have at least one part graded D or F.

• Drinking water: Mackenzie Ridge Llc meets every EPA legal limit; 3 contaminants are above health goals, led by lead at 33× California’s Public Health Goal.
• Nearest Superfund site: Washington County Lead District - Potosi, 4.0 miles away (2 within 10 miles).
• Largest share of modeled toxic air from industry: Buckman Laboratories Inc. (71%), mostly bis(2-chloroethyl) ether.
• Fine particles (PM2.5) average 6.7 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 2,730 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 63020

• Superfund sites nearbyF
• Factories and industrial sitesA to C
• Oil and gas wellsA to B
• Parks and nature nearbyC
• Air qualityA to B
• Drinking water qualityC to F
• Pesticide useD
• Neighborhood health statusD to F
• Past wildfire impactsA
• Past flood impactsA to F
• Noise levelsA to D
• Radiation signalsC to D

Based on 11 census tracts · compiled September 10, 2026 · how each grade works and its sources

Loading the full report, with every source…