Total Trihalomethanes (TTHM)
Unresolved Total Trihalomethanes Rule violation cited in 2024 (total trihalomethanes (tthm)).
City · TRI 2024
Souris, North Dakota Pollution
0 TRI facilities inside the city limits and 1 public water system serving residents.
FIPS 3874020 · population 57 · Bottineau County
Anomaly engine
Notable Signals
Total Trihalomethanes (TTHM)
Total Trihalomethanes Rule health-based violation cited in 2024 (total trihalomethanes (tthm)).
Pollutant pathways
Souris Pollutant Multi-Year Trends
Lifetime cancer risk all pollutants (100 in a million (EPA elevated threshold))Health riskEPA-modeled added cancer cases per million residents from a lifetime of breathing local air toxics. EPA flags 100-in-a-million as elevated.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
Formaldehyde ambient mean (0.077 µg/m³ (1-in-a-million URE))Health riskAn air toxic emitted by refineries, wood products, and combustion. EPA classifies it as a known human carcinogen — long-term inhalation raises cancer risk.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
Benzene ambient mean (0.13 µg/m³ (1-in-a-million URE))Health riskAn air toxic from gasoline, refineries, and tobacco smoke. A known human carcinogen — chronic exposure is linked to leukemia and other blood cancers.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
TRI air releases (5.1 fugitive + 5.2 stack)Health riskToxic chemicals reported by industrial facilities as released into the air — fugitive leaks plus smokestack emissions. Higher pounds means more inhaled exposure for nearby residents.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
TRI water releases (5.3)Health riskToxic chemicals reported by industrial facilities as discharged to surface waters (rivers, lakes, the ocean). Affects fishing, recreation, and downstream drinking-water intakes.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
TRI land + off-site releasesHealth riskToxic chemicals released to land on-site or transferred off-site for disposal — landfills, deep-well injection, and similar. Risks groundwater contamination over time.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
Drinking water · SDWIS
Water Systems Serving Souris
1 unresolved violation on the SDWIS record across utilities serving this city.
1
Utilities serving
58
Population served
4
Health-based · 5yr
1
Unresolved
| Water system | PWSID | Population served | Health-based · 5yr | Status |
|---|---|---|---|---|
| Souris City Of Municipal | ND0500887 | 58 | 4 | UNRESOLVED |
A public water systemis the regulated entity, not the city. EPA's SDWIS definition covers anything serving 25+ people for 60+ days a year or with 15+ service connections — that includes municipal utilities (City of Stockton), water districts, mobile home parks operating their own wells, schools, and small private subdivisions. Each system is independently monitored. Some systems serve multiple cities; some cities are served by many systems.
Equity context · ACS 2018-2022 · USEPA-clone EJ disparity
Who Lives In Souris
Souris, North Dakota (Census place block groups): 57 residents. Why we surface this →
19.3%
Low-income
0.0%
People of color
0.0%
Under age 5
26.3%
Over age 64
Source: Census ACS 2018-2022 (5-year) + USEPA-clone EJ blockgroup stats (raw indicators + EJ disparity mirror).
Sources.
- EPA Toxics Release Inventory · retrieved 2026-05-07.
- EPA Safe Drinking Water Information System · retrieved 2026-05-07.