Jefferson County, MT
The federal environmental record for Jefferson County (population 13,048): what is on file, where it is, and what remains open. Sources and retrieval dates are on the methodology page.
1
Superfund NPL sites
10
federal cleanup sites
0
PFAS-detecting water systems
3
TRI facilities
7
open tank releases
Superfund NPL sites
| Site | City | Status | Listed |
|---|---|---|---|
| Basin Mining Area | Basin | on the NPL | 10/22/1999 |
Drinking water: PFAS testing
No public water system serving Jefferson reported a PFAS detection in the UCMR5 national testing round. Systems serving under 3,300 people were only sampled in part, so absence from this table is not proof of absence in the water.
Facilities reporting toxic releases (2024)
3 facilities in Jefferson filed TRI reports for 2024, totalling 57k lb released.
| Facility | City | Top chemicals | Total released |
|---|---|---|---|
| BARRICK GOLD CORP-GOLDEN SUNLIGHT MINE | WHITEHALL | Lead compounds | 52k lb |
| ASH GROVE CEMENT CO MONTANA CITY PLANT | CLANCY | Lead compounds, Chromium | 5k lb |
| MARKS-MILLER POST & POLE INC | CLANCY | - | 0 lb |
Underground fuel tanks
EPA's UST Finder records 54 tank facilities in Jefferson: 28 tanks in service and 124 closed. 60 fuel releases are on record, of which 7 remain open. Open releases are cleanups that have not reached "no further action".
Radon
EPA maps Jefferson as Zone 1, the highest predicted indoor radon levels (over 4 pCi/L average). Radon and air quality are covered in depth on lung.com.
The record for one specific address
County figures blur what matters: distance. The Address Environmental Report runs these same federal datasets against one address and reports every site, tank, polluter and water result around it, with distances, in about a minute.
Get the report - $39All federal cleanup sites on file
The wider Superfund enterprise inventory (SEMS) for Jefferson, including sites assessed but never listed. Presence here records that EPA had reason to look, not a finding of danger.
- BASIN MINING AREABASIN
- BOULAWAYELKHORN
- C&D MINEBOULDER
- CARMODYBOULDER
- ELKHORN CREEK TAILINGSELKHORN
- ELKHORN QUEEN (22-027)ELKHORN
- IRON MINEBOULDER
- SKYLINEELKHORN
- TACOMA (22-284)BOULDER
- UNION ELKHORNELKHORN