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DeutschAddress report

States / Montana

Lewis and Clark County, MT

The federal environmental record for Lewis and Clark County (population 75,011): what is on file, where it is, and what remains open. Sources and retrieval dates are on the methodology page.

2

Superfund NPL sites

12

federal cleanup sites

0

PFAS-detecting water systems

2

TRI facilities

52

open tank releases

Superfund NPL sites

SiteCityStatusListed
East Helena SiteEast Helenaon the NPL09/21/1984
Upper Tenmile Creek Mining AreaHelena, Riminion the NPL10/22/1999

Drinking water: PFAS testing

No public water system serving Lewis and Clark 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)

2 facilities in Lewis and Clark filed TRI reports for 2024, totalling 19k lb released.

FacilityCityTop chemicalsTotal released
AMERICAN CHEMET CORPEAST HELENACopper And Copper Compounds, Ammonia14k lb
US ARMY NATIONAL GUARD FORT HARRISON RANGESFORT HARRISONLead5k lb

Underground fuel tanks

EPA's UST Finder records 283 tank facilities in Lewis and Clark: 140 tanks in service and 603 closed. 236 fuel releases are on record, of which 52 remain open. Open releases are cleanups that have not reached "no further action".

Radon

EPA maps Lewis and Clark 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 - $39

All federal cleanup sites on file

The wider Superfund enterprise inventory (SEMS) for Lewis and Clark, including sites assessed but never listed. Presence here records that EPA had reason to look, not a finding of danger.

  • ASARCO SODIUM - EAST HELENAEAST HELENA
  • BNRR DERAILMENT-HELENA-ELEC SUB-STATIONHELENA
  • EARTHQUAKE MINEMARYSVILLE
  • EAST HELENA SITEEAST HELENA
  • MONTANA ARMY NG MRS PROGRAMFORT HARRISON
  • NEENAN MINEMARYSVILLE
  • SNOW DRIFT MINEMARYSVILLE
  • TOWSLEY II MINEMARYSVILLE
  • UNKNOWN 8 TAILINGSMARYSVILLE
  • UPPER TENMILE CREEK MINING AREAHELENA
  • VA MT HLTH CARE SYSTEMS FORT HARRISONFORT HARRISON
  • WILDCAT LEACH SITEMARYSVILLE