Dillingham County, AK

ZIP 99555

In ZIP 99555, 2 of the 12 things we check have at least one part graded D or F.

Drinking water: New Stuyahok Water System meets every EPA legal limit; 3 contaminants are above health goals, led by arsenic at 304× California’s Public Health Goal.
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: Trident Seafoods North Naknek Facility (100%), mostly naphthalene.
Fine particles (PM2.5) average 4.2 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.

Grades for ZIP 99555

Based on 1 census tract · compiled September 10, 2026 · how each grade works and its sources

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