Sweetwater, WY
A PlainEnviro-computed score from reported facility/violation counts, not an official EPA rating, health forecast, or population-adjusted rate. See methodology. This is a different measure than the EJ Screening score for this county, which ranks it by percentile against every other tracked county rather than against fixed national thresholds.
Environmental data for Sweetwater in Wyoming · Population: 41,786
Sweetwater, WY is tracked across three EPA datasets covering 11 Toxics Release Inventory (TRI) facilities, 19 Safe Drinking Water Act systems, and 0 Superfund National Priorities List sites. Together these generate an environmental burden score of 53/100 (Moderate Risk), calibrated against national distributions for facility density, chemical release volume, Superfund concentration, and water-system health violations.
Industrial disclosures inside the county total 18.2M lbs of reported toxic releases under EPCRA Section 313, while 8 water systems carry an active health-based violation in the SDWIS record. EPA Air Quality System monitors logged a median AQI of 45 and a peak AQI of 137 in 2024, with 67% of observed days rated "Good" (0–50).
All figures below draw directly from federal EPA records, TRI self-reported emissions, SDWIS compliance history, NPL Hazard Ranking System scores, and AQS daily AQI summaries, and are not adjusted, weighted, or forecast. A past violation or elevated score does not itself indicate current unsafe conditions; it documents the regulatory and disclosure history publicly filed with the U.S. Environmental Protection Agency through the most recent reporting cycle.
Air Quality History (2020–2024)
EPA Air Quality Index (AQI) data showing how many days per year fall into each air quality category.
| Year | Good | Moderate | Unhealthy (SG) | Max AQI |
|---|---|---|---|---|
| 2024 | 247 (67%) | 109 | 10 | 137 |
| 2023 | 253 (69%) | 103 | 8 | 211 |
| 2022 | 285 (78%) | 78 | 1 | 157 |
| 2021 | 238 (65%) | 117 | 9 | 195 |
| 2020 | 235 (64%) | 119 | 7 | 1334 |
Source: EPA Air Quality System (AQS) Annual AQI by County EPA Air Quality System (AQS) Annual AQI by County AQI categories: Good (0-50), Moderate (51-100), Unhealthy for Sensitive Groups (101-150), Unhealthy (151-200), Very Unhealthy (201-300), Hazardous (301+)
For real-time air quality readings and pollutant breakdowns in Wyoming, see the EPA's AirNow.gov.
Water Systems (19)
| System | Population | Violations |
|---|---|---|
| ROCK SPRINGS, CITY OF | 24,000 | 0 |
| GREEN RIVER, CITY OF | 10,500 | 0 |
| LITTLE AMERICA HOTELS & RESORTS, INC- WY | 2,004 | 26 |
| PIONEER MOBILE HOME PARK | 1,000 | 0 |
| CLEARVIEW I&S DISTRICT | 930 | 0 |
| JAMESTOWN-RIO VISTA W&S DISTRICT | 560 | 0 |
| FARSON EDEN SCHOOL | 530 | 1 |
| WAMSUTTER, TOWN OF | 500 | 3 |
| LEWIS MOBILE HOME PARK | 370 | 0 |
| SUPERIOR, TOWN OF | 336 | 2 |
| HORIZON MHP | 330 | 0 |
| MOBILE CORRALS/STALLS COURT | 300 | 0 |
| WHITE MOUNTAIN MOBILE HOME PARK | 270 | 0 |
| GRANGER, TOWN OF | 139 | 6 |
| DESERT TRAILS MHP | 112 | 0 |
| POINT OF ROCKS MERCANTILE | 78 | 1 |
| BAIROIL, TOWN OF | 71 | 1 |
| ROCK SPRINGS/GREEN RIVER JPB | 25 | 3 |
| FARSON MOBILE HOME COURT | 20 | 0 |
TRI Facilities (11)
| # | Facility | Total Releases |
|---|---|---|
| 1 | Simplot Phosphates LLC | 10.3M lbs |
| 2 | Pacificorp Jim Bridger Plant & Bridger Coal Co | 6.7M lbs |
| 3 | Blacks Fork Gas Plant | 1.1M lbs |
| 4 | Granger Gas Plant | 46.0K lbs |
| 5 | Vermillion Gas Plant | 32.6K lbs |
| 6 | Black Butte Coal Co | 530 lbs |
| 7 | Church & Dwight Co Inc | 111 lbs |
| 8 | P4 Production LLC | 110 lbs |
| 9 | Lewis & Lewis Inc Asphalt Paving | 2 lbs |
| 10 | Sunroc Corp - Lagoon Drive Ready Mix | 0 lbs |
| 11 | Western Refining -Dba Pilot Thomas Logistics - Rock Springs | 0 lbs |
Cities in Sweetwater (4)
Frequently Asked Questions
What is the environmental risk level in Sweetwater, Wyoming? ▼
Are there Superfund sites in Sweetwater? ▼
How many toxic release facilities are in Sweetwater? ▼
What is the air quality in Sweetwater? ▼
Is the drinking water safe in Sweetwater? ▼
What environmental agencies cover Sweetwater? ▼
What does this county environmental profile show?
This county environmental profile rolls up EPA Toxics Release Inventory facility reports, Safe Drinking Water Information System public-water-system filings, and Superfund National Priorities List sites for the county boundary defined by the U.S. Census Bureau. Facility counts reflect facilities with a reporting address inside the county, not where downstream environmental effects may be observed. Population figures are from the most recent Census ACS 5-year estimate. The county detail page is updated whenever the upstream EPA programs publish revised data; see the methodology page for the documented ingest cadence and the editorial choices governing how aggregations are computed.
Read our methodology - how this data is sourced, computed, and verified.