St. Mary Parish, LA

ZIP 70340

In ZIP 70340, 5 of the 12 things we check have at least one part graded D or F.

• Drinking water: City Of Morgan City Water System meets every EPA legal limit; 16 contaminants are above health goals, led by lead at 56× 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: Bollinger Marine Fabricators LLC (74%), mostly chromium.
• Fine particles (PM2.5) average 8.1 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 128,132 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 70340

• Superfund sites nearbyA
• Factories and industrial sitesC
• Oil and gas wellsF
• Parks and nature nearbyB
• Air qualityD
• Drinking water qualityD to F
• Pesticide useF
• Neighborhood health statusD
• Past wildfire impactsA
• Past flood impactsB
• Noise levelsA
• Radiation signalsB

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

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