Having undertaken an ambitious project — cleaning up 44 river miles on the Clark Fork — the state has so far removed about 1.2 million cubic yards of “dirty dirt” in both Powell and Anaconda-Deer Lodge counties.
The overall cost of the project is $123 million, said Jenny Chambers, Department of Environmental Quality waste management and remediation division administrator. The work is expected to continue at least another 15 years.
The “dirty dirt” is soil contaminated from heavy metals, mostly copper. The metals contamination occurred in 1908 when a 100-year flood washed significant amounts of metals from smelter sites upstream around Butte all the way to the former Milltown Dam just east of Missoula. The Environmental Protection Agency had Milltown Dam removed in 2008 to clean the contaminated sediment that landed there a 100 years ago. Atlantic Richfield Company, the responsible party, did the work.
The state has taken the lead on the Clark Fork River cleanup work, which began in 2009, Chambers said. Deer Lodge was the site of the initial work. After that was complete, DEQ moved south to begin about three-quarters of a mile below Warm Springs Ponds. Overall, the excavation and replanting work is expected to pass the Grant-Kohrs Ranch downstream of Deer Lodge.
About eight river miles have been excavated and replanted with vegetation so far. The Natural Resource Damage Program, the state agency responsible for restoring cleaned up sites, has worked hand in hand with DEQ on the project.
Last week, the Clark Fork Coalition, a Clark Fork River environmental group, teamed up with Ecoflights, a Colorado-based environmental nonprofit, to provide short flights for local media, state and county officials to get an overview of the work DEQ and NRD have accomplished so far.
DEQ dug out the “dirty dirt” initially on state land near Warm Springs Ponds before moving onto taking out the contaminated soil along Dry Cottonwood Creek Ranch. The latter is an operating ranch the Clark Fork Coalition purchased in 2005 so the state could have place for trial and error in the early stages of their work on the river.
As part of the process of working with landowners, DEQ helps with weed control and puts up temporary fencing. DEQ also compensates ranchers for lost haying and lost grazing due to the Clark Fork cleanup.
Montana Fish, Wildlife and Parks has also worked with DEQ to close sections of the river to public access to give the river bank time to recover after the completed phases are done.
“This is major surgery,” NRD program manager Harley Harris said of the access closures during the flight. “We need to keep (sections of) the river closed for a period of time to heal.”