EPA-regulated facilities in Big Horn County, MT

There are 371 EPA-regulated facilities inside Big Horn County, Montana. The most common kinds are water discharge (268), hazardous waste (46), drinking water systems (36). 3 are currently in significant noncompliance, the EPA's designation for the most serious or persistent violations, and 17 have a violation on record. Penalties over the last five years total $1k across 1 site.

Open the map of Big Horn County

371facilities in the county

3in significant noncompliance

17with a violation on record

$1kin penalties, last 5 years

By category

Category	Facilities
Hazardous waste	46
Large quantity generators	1
Small quantity generators	24
Chemical (RMP/TRI)	5
Superfund	2
Air emissions	35
Major sources	2
Synthetic minor sources	1
Minor sources	1
Water discharge	268
Major permits	3
Minor permits	202
Drinking water systems	36
Greenhouse gas reporters	1
Data centers	1

A facility enrolled in several programs counts once in the total and once in each of its categories.

In significant noncompliance

The EPA's designation for its most serious or persistent violations, as of the latest data.

CROW AGENCY WATER SYSTEM CROW AGENCY, CROW AGENCY, MT, 59022 Significant noncompliance
PRYOR WATER SYSTEM-WL03 PUMPHOUSE P.O. BOX 129, CROW AGENCY, MT, 59022 Significant noncompliance
LODGE GRASS, TOWN OF WWTF SE 1/4, SEC. 12 T65N, R35W, LODGE GRASS, MT, 59050 Significant noncompliance

Largest penalties

Penalties assessed over the last five years.

HARDIN WWT FACILITY 406 N. CHEYENNE AVENUE, HARDIN, MT, 59034 $1k in penalties

Superfund sites

LODGE GRASS DRUMS 111 SITE HAS NO ADDRESS, LODGE GRASS, MT, 59050
USBR YELLOWTAIL DAM AND POWER PLANT YELLOWTAIL FIELD BRANCH 2 AVENUE B, FORT SMITH, MT, 59035

Data centers

LIEFERN DATA CENTER 643 INDUSTRIAL PARK ROAD, HARDIN, MT, 59034

Bordering counties

Reading these numbers

These are regulatory records, not measurements of pollution. Most facilities appear because they hold a permit or file reports, and most of them are compliant; a listing is not a claim that a facility has polluted anything. Compliance status and penalties are the EPA's own determinations in data retrieved Oct 9, 2026. The Data page explains where each record comes from and how it can mislead.