GALEN – Just east of the Racetrack exit off Interstate 90, the Clark Fork River is undergoing a major remodeling job.
It doesn’t look much like a river up here in the Deer Lodge Valley. Some of the dump trucks roaming around the north side of the freeway look like they could straddle both banks without wetting a tire. But hidden in the headwaters is a century-old legacy of toxic mining waste that’s finally getting cleaned up.
“This area was a lush willow shrub community with lots of grasses,” Clark Fork Coalition stream restoration director Will McDowell said of the work site, which gobbles about 200 acres of the coalition’s Dry Cottonwood Creek Ranch. “But in places, it was so contaminated there were blue-green spots where nothing would grow. This is a gigantic transformation from what was here before.”
The Clark Fork River Operable Unit, as it’s known in the federal Superfund program, extends 47 miles from the confluence of Silver Bow and Warm Springs creeks down to Garrison. This is where tons of heavy metal sediments got deposited in a massive flood in 1908. Much of that hazardous material piled up behind Missoula’s Milltown Dam, which got its own Superfund project to clean it up. But the upper Clark Fork also suffered from serious contamination with arsenic, lead, cadmium, copper and zinc.
While the deposits aren’t high enough to threaten humans (unless they deliberately eat a lot of dirt), the slickens have suppressed plant growth in places along the riverbank for more than a century. The upper Clark Fork trout fishery is also about one-fifth the productivity that similar rivers support – likely due to the heavy metals suppression of aquatic insects.
CFC officials volunteered to use their working cattle ranch as the first private property phase of the work, which has already remediated some state land around the headwaters. About 300 landowners are affected along the 47 miles of upper Clark Fork. The Department of Environmental Quality has designed a 22-phase work plan to transform the river basin into a healthy, productive waterway.
That transformation has been a bit of a hard sell for some riverside landowners, according to DEQ environmental project manager Brian Bartkowiak. It takes some faith to trust that the government can turn a pretty river bottom into a moonscape and then return it to productive, attractive ranch land. A few neighbors aren’t convinced there’s a serious contamination problem at all, or that it’s naturally healing itself.
“There’s been a lot of controversy over the size and timing of the project,” Bartkowiak said. “But most of the calls I’m getting now are about when are we getting to their property.”
The project is funded through a $96 million settlement between the state and Arco, the legacy corporation responsible for mining activities in Butte and Anaconda. The phase by Galen is expected to cost about $8.9 million.
DEQ intends to have two or three phases active at any one time. Work crews will leapfrog up and down the drainage. That way, if a seasonal flood ever happens, high water will always have some undisturbed land to absorb the energy instead of crashing into an extended excavation zone.
The restoration focuses on toxic deposits along the riverbank and its old dry channels, but won’t remove anything from the riverbed itself. The goals are to allow healthy river habitat to regrow and prevent future floods from tearing out the old slickens and transporting them to new places downstream.
“Plants are what keep this river together,” said Tom Mostad of the state Natural Resource Damage Program, which works with DEQ on the restoration and rehabilitation. “They’re not a luxury afterthought. You’ve got to design carefully to get what you’re after.”
So carefully, five separate seed mixes have been compiled for planting at different elevations from the water to two feet up the bank. The recipe changes every few inches, as the amount of moisture varies above the water line.
Many of the techniques were first tested and perfected downstream at the Milltown Dam Superfund site. Visitors familiar with that project will see the same coir logs of coconut-fiber-wrapped soil studded with willow stakes lining rebuilt riverbanks, and seemingly desolate piles of dead brush that will catch sediment and seeds for future regrowth. Some borrow pits for soil and gravel that shape the new floodplain will become future wetland ponds for ducks and waterfowl.
All that will be on display next Wednesday when DEQ officials lead a public tour of the Dry Cottonwood Creek Ranch phase.
“This is everyone’s opportunity to see what’s going on,” Bartkowiak said. “It’s really the public’s tour, a chance to get out here and ask questions.”