Loudoun County, VA

ZIP 20165

In ZIP 20165, 7 of the 12 things we check have at least one part graded D or F.

• Drinking water: Fairfax County Water Authority has 2 contaminants at or over an EPA legal limit; 12 contaminants are above health goals, led by pfos at 5.2× California’s Public Health Goal.
• Nearest Superfund site: Hidden Lane Landfill, 1.6 miles away.
• Largest share of modeled toxic air from industry: Micron Technology Inc. (49%), mostly chlorine.
• Fine particles (PM2.5) average 8.0 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 97,008 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 20165

• Superfund sites nearbyD to F
• Factories and industrial sitesA to B
• Oil and gas wellsA
• Parks and nature nearbyC to F
• Air qualityC to D
• Drinking water qualityD to F
• Pesticide useC to D
• Neighborhood health statusA to B
• Past wildfire impactsA
• Past flood impactsB
• Noise levelsA to D
• Radiation signalsC to D

Based on 7 census tracts · compiled September 10, 2026 · how each grade works and its sources

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