Grant County, WA

ZIP 99321

In ZIP 99321, 4 of the 12 things we check have at least one part graded D or F.

• Drinking water: Sentinel Gap Water Assn meets every EPA legal limit; 10 contaminants are above health goals, led by arsenic at 280× California’s Public Health Goal.
• Closer to Superfund sites than 55% of U.S. neighborhoods, with no listed site within 10 miles of its center.
• Largest share of modeled toxic air from industry: Yakima Training Center- Range (84%), mostly lead compounds.
• Fine particles (PM2.5) average 7.3 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 5,279,716 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 99321

• Superfund sites nearbyA to C
• Factories and industrial sitesA to B
• Oil and gas wellsA
• Parks and nature nearbyB to C
• Air qualityB to C
• Drinking water qualityC to D
• Pesticide useF
• Neighborhood health statusB to C
• Past wildfire impactsD to F
• Past flood impactsA
• Noise levelsA
• Radiation signalsD

Based on 2 census tracts · compiled September 10, 2026 · how each grade works and its sources

Loading the full report, with every source…