St. Charles County, MO

ZIP 63341

In ZIP 63341, 5 of the 12 things we check have at least one part graded D or F.

• Drinking water: Lake Sherwood Subd meets every EPA legal limit; 6 contaminants are above health goals, led by lead at 18× California’s Public Health Goal.
• Nearest Superfund site: Weldon Spring Quarry/plant/pits (usdoe/army), 0.5 miles away (3 within 10 miles).
• Largest share of modeled toxic air from industry: Ameren Missouri Labadie Energy Center (55%), mostly chromium compounds.
• Fine particles (PM2.5) average 7.9 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 138,436 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 63341

• Superfund sites nearbyD to F
• Factories and industrial sitesB
• Oil and gas wellsA to B
• Parks and nature nearbyC
• Air qualityB to D
• Drinking water qualityD
• Pesticide useD to F
• Neighborhood health statusC
• Past wildfire impactsA
• Past flood impactsA
• Noise levelsA
• Radiation signalsC to D

Based on 3 census tracts · compiled September 10, 2026 · how each grade works and its sources

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