Chester County, PA

ZIP 19425

In ZIP 19425, 7 of the 12 things we check have at least one part graded D or F.

• Drinking water: Valley Run Water System meets every EPA legal limit; 10 contaminants are above health goals, led by pfos at 2.3× California’s Public Health Goal.
• Nearest Superfund site: A.i.w. Frank/mid-County Mustang, 4.6 miles away (3 within 10 miles).
• Largest share of modeled toxic air from industry: Carpenter Technology Corp (41%), mostly chromium.
• Fine particles (PM2.5) average 7.6 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 156,614 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 19425

• Superfund sites nearbyD to F
• Factories and industrial sitesC to D
• Oil and gas wellsA
• Parks and nature nearbyC to D
• Air qualityB to C
• Drinking water qualityD to F
• Pesticide useD to F
• Neighborhood health statusA to C
• Past wildfire impactsA
• Past flood impactsC
• Noise levelsA to D
• Radiation signalsD to F

Based on 9 census tracts · compiled September 10, 2026 · how each grade works and its sources

Loading the full report, with every source…