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Silver Bow Creek/Stream Side Tailings

  Silver Bow Creek map


Picture of boy with trout 2009 mink return to SBC

Ospray and Fish, Photo taken by Don MacGee.

Summer 2011

Young angler, Rye Vincent, holding 18.5 inch cutthroat trout catch from Siver Bow Creek just below Miles Crossing bridge.

Summer 2010

This mink was seen along Silver Bow Creek in September 2009.

Mink prey on fish so the presence of mink indicates a return of fish to the stream.

Interactive Story Map

The cleanup of Silver Bow Creek has been ongoing since 1999 as part of a Superfund remedial action being coordinated by the Montana Department of Environmental Quality (DEQ) in consultation with the U.S. Environmental Protection Agency (EPA). In 2000, the Natural Resource Damage Program (NRDP) of the Montana Department of Justice formed a partnership with DEQ, bringing a restoration component to the project that goes beyond remediation required under Superfund. Provided below is a brief history of the project, updates regarding the current status of the project, and descriptions of activities planned in future years.


Silver Bow Creek extends from Butte approximately 23 miles to the Warm Springs Ponds, a water treatment facility located at the headwaters of the Clark Fork River (see corridor map). Since the late 1800s, tailings and other mine wastes containing elevated concentrations of metals have been discharged to or otherwise entered Silver Bow Creek. These toxic discharges impacted the stream and floodplain with heavy metals and virtually eliminated aquatic life in the stream. Tailings deposited in the floodplain are toxic to plants and have resulted in a floodplain that is largely devoid of vegetation and is generally incapable of supporting wildlife. In 1983, EPA listed the Silver Bow Creek/Butte area as one of multiple Superfund sites in the Upper Clark Fork River Basin. The agency later designated the approximately 23 stream miles of streamside tailings along Silver Bow Creek as an operable unit (OU) within this overall Superfund site. The Streamside Tailings Operable Unit (SSTOU) has become one of the areas of focus for Superfund cleanup in the Butte area. Initially, EPA named ARCO as the primary party responsible for remediation of the SSTOU and other Superfund sites in the Upper Clark Fork Basin through its acquisition of the Anaconda Company. EPA and DEQ issued a Record of Decision (ROD) for the site in November 1995 that identifies the final site remedy and the agencies' rationale for selecting that remedy. The major remedial action that resulted from issuance of the ROD is excavation of tailings and related impacted soils from the floodplain of Silver Bow Creek and reconstruction of the stream channel and floodplain. For planning purposes, the SSTOU was divided into four subareas, each with a distinct geologic and geographic character.

The Natural Resources Damage Program (NRDP) Connection. In a 1999 state, federal and tribal settlement, ARCO agreed to pay $215 million to the State to resolve certain claims. From the settlement amount, $80 million plus interest was set aside for DEQ and EPA to implement the remedy for Silver Bow Creek. Some of the remaining amount is being used to enhance the cleanup of Silver Bow Creek through various habitat improvements and restoration actions. DEQ and EPA are coordinating the cleanup of the Silver Bow Creek remedy with NRDP.

Cleanup Reaches Completion

After 16 years of cleanup, the Silver Bow Creek/Streamside Tailings cleanup reached completion in summer 2015. 

Cleanup consisted of excavation of tailings (mine waste containing heavy metals) and related impacted soils from the floodplain of Silver Bow Creek, and the reconstruction of the stream channel and floodplain, and total revegetation. 5.8 million cubic yards of tailings were hauled, or enough to fill Grizzly Stadium to the brim 21 times. The contaminated waste was hauled to Opportunity Ponds. Approximately 1,550 acres along Silver Bow Creek have been remediated and restored.

Fish surveys show that populations of Westslope cutthroat, brook trout, sculpins, and suckers have reestablished in the creek. Shrub and tree planting activities have enhanced wildlife habitat, along with a DEQ-implemented weed management program. Sightings of over 100 bird species, including bald eagles, osprey, swans, blue heron, and sandhill crane are common in the floodplain and wetland areas, as well as deer, elk, moose, beaver, muskrats, and mink.

DEQ will implement a "final pass" cleanup before subareas are transitioned into operations and maintenance status. The final pass will address very small deposits of remaining remnant tailings-impacted soils to improve and enhance the remediation as a whole.  


MT DEQ Logo EPA Region 8 Superfund Program Contacts
Joel Chavez Kristine Edwards
Project Officer
P.O. Box 200901
Helena MT  59620-0901
1-800-246-8098 (in-state only)
Remedial Project Manager
U.S. EPA, Montana Office
10 West 15th Street, Suite 3200
Helena, MT 59626