CFWEP | Clark Fork Watershed Education Program
CFWEP | Clark Fork Watershed Education Program
What is the Clark Fork Watershed?
The Clark Fork River and its tributaries drain most of western Montana. The upper river and headwaters were heavily impacted by wastes from over a century of mining. Today, the area is the largest Superfund environmental clean-up site in the nation.

CFWEP Upcoming Events
-May 28: Deadline for public comments on Anaconda area Superfund sites.
-June 1: CFWEP Field Trip with Deer Lodge School.
-June 4-6: Butte: The Original film showings at the Motherlode Theatre in Butte.

CFWEP E-Newsletter
Spring 2010
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Clark Fork Info > Restoration

The Clark Fork River connects the largest complex of federal Superfund environmental clean-up sites in the U.S. The Basin is divided into sub-areas where various environmental reclamation and restoration projects are underway. Some of these sites are shown in the photos below. Click on the links below to learn more about specific restoration projects around the basin, or visit the Clark Fork Info > Links page for more in-depth information from government agencies and groups leading restoration projects. Also visit our Conservation & Superfund Library to download a wide variety of public documents and technical reports related to Superfund and restoration projects in western Montana, and visit our News page for comprehensive, up-to-date news links related to the Clark Fork Basin, environmental science, Superfund, conservation, and Montana's ecosystems.

The Clark Fork Basin Superfund area. The Basin is divided into sub-areas where various environmental reclamation and restoration projects are underway.

Photo Key:

1. The Milltown Dam: Located at the confluence of the Clark Fork and Blackfoot Rivers. A 1908 flood washed tailings, fine-grained sediment rich in heavy metals and other toxins, from the Butte mines and Anaconda smelters down the Clark Fork River to the dam, where much of the contaminated sediment settled in the reservoir. Over the past several years, the dam has been removed, contaminated sediments are being removed from the reservoir, and the confluence of these two great rivers is being restored.

2. The Anaconda Smelter: Ore from the Butte mines was smelted in Anaconda throughout the 20th century. Air pollution from smelting impacted the Deer Lodge valley to the north. The Anaconda smelter stack stands as a visual reminder of the town's smelting legacy.

3. The Opportunity Ponds, aka The BP-Arco Waste Repository: Near the town of Opportunity, this area long served as a tailings dump for the Anaconda smelters. Processed mine waste (tailings) from the smelters was mixed with water (slurried) and pumped to the site. The Waste Repository has not truly been a "pond" for many years. Since the closure of the smelter in the 1970's, no water has been pumped to the site, leaving the tailings deposits to dry out, and creating potential dust concerns for nearby residents. The area covers approximately five square miles, with tailings deposits averaging about 20 feet deep; in the upper tiers of the repository, tailings deposits are as much as 80 feet deep. To learn more about the Opportunity Ponds, click here to download the "Opportunity, Montana: A Brief Historical Introduction" PowerPoint Presentation.

4. The Mainstem Clark Fork River: Tailings from the Butte mines carried downstream, particularly in an historic 1908 flood, and significantly impacted the main Clark Fork River from the Warm Springs Ponds near Anaconda past Deer Lodge until the river narrows and gains more volume from the Little Blackfoot River at Garrison. Air pollution from Anaconda smelting also negatively impacted vegetation and livestock in the Deer Lodge valley. In this photo, a CFWEP student takes water quality readings.

5. Restoration: Active remediation and restoration projects are underway around the basin. Many involve students, like the Anaconda High School students shown here helping to revegetate the Silver Bow Creek floodplain near the town of Ramsay by planting trees.

6. Monitoring: As the health of ecosystems around the basin is restored, ongoing monitoring of water quality and biological communities helps to ensure the future health of the area. In this photo, CFWEP students look at macroinvertebrates, stream-dwelling insects, to assess the health of the riparian ecosystem.

7. The Yankee Doodle Tailings Pond: While the Clark Fork basin is restored, mining continues in Butte at the Continental Pit, an open pit mine operated by Montana Resources, Inc. While in the past mine waste from Butte was discarded into Silver Bow Creek, today tailings and waste rock are sequestered away from the creek and the Clark Fork River. Tailings are slurried with water and pumped to the Yankee Doodle Tailings Pond north of Butte and Berkeley Pit. An earthen dam separates the Yankee Doodle from the greater watershed, and tailings are slurried with lime rock to reduce acidity and cause metals to settle out at the bottom of the ponds. The remaining water is relatively clean, and the Yankee Doodle Ponds are often used by birds and other wildlife.

8. The Berkeley Pit: Begun in 1955 and abandoned in 1982, Butte's first open pit mine has since filled with acidic water rich in heavy metals and other toxins. A high iron content sometimes gives the water near the surface a reddish appearance, as seen in this photo. The Berkeley Pit acts as a terminal sink, so none of the contaminated water ever leaves the confines of the pit. Water levels have slowly risen over time, but before the water reaches a level where it could infiltrate surrounding groundwater or surface water, it will be pumped from the pit, treated to discharge standards, and released in Silver Bow Creek. Current projections indicate that the critical water level will be reached around 2023. A treatment plant, the Horseshoe Bend Water Treatment Plant, has already been constructed. It currently captures and treats surface water that would flow into the pit. This water is re-used in Montana Resources' Continental Pit mining operations. The Horseshoe Bend Plant will eventually treat Berkeley Pit water to prevent the pit lake from rising to critical levels.

Other Clark Fork Sites:

Butte Priority Soils Operable Unit (Butte Area)

Streamside Tailings Operable Unit (Silver Bow Creek)

Warms Springs Ponds



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