Second phase of Flat Creek cleanup planned

It was 20 years ago that the Federal EPA came to Superior to investigate the possibility of soil contamination. That is when the first critical action removal was performed.

“We listed Flat Creek to the Superfund national priorities list in September of 2009,” explains Allie Archer, EPA Superfund Project Manager. “And Flat Creek in Superior became a Superfund site. Superior’s cleaning was completed in 2011 and 2012. The lawns have been remediated and driveways have been refurbished.”

But another phase is coming this summer that moves farther up the watershed.

"Legacy mine waste" is what it is known as in environmental cleanup circles and that’s what is left up the Flat Creek drainage.

“We consider this mine waste has potential harm to human health and environmental impacts which we are working forward to alleviate,” shared Bob Wintergerst, USFS Regional Environmental Engineer based out of Missoula. “Some of that land is administered by the USFS and we have a role to help mitigate to bring it back into production and remove the risk to human health and human environment. We have done this in steps. In 2016 and 2017 we did a major portion of the cleanup which started at the historic mill site at the confluence of Hall Gulch and Flat Creek. That land is now privately owned but was once the property of ASARCO Mining Company. The remaining step is cleanup on a couple of stretches on Flat Creek which are on lands administered by the USFS.”

This will be a two-year project starting late spring of this year.

“The first season we are going to excavate the repository near Woods Gulch for the new cell which is being done through a joint effort by the Forest Service and Trout Unlimited,” he said.

Trout Unlimited is involved because there are pools of fish farther up Flat Creek and they have the expertise to protect and build a fishery as needed. Flat creek has a pure strain cutthroat trout population above where the historic mining occurred.

Access for things like hunting and fire response will be maintained throughout the project and it is estimated that they will remove approximately 14,000 cubic yards of tailings. Phase 2, to be conducted in 2023, will complete the project on the remaining lower reach of Flat Creek on USFS property, involving an estimated 4,700 cubic yards. This part of Flat Creek is more incised, more vegetated and has some larger tailings deposits.

This will be monitored by the state DEQ to meet their specifications as they will be the long-term caretaker of the repository since this is on state land. Archer and her department will investigate to make sure there are no additional issues in Flat Creek as there is adit that has acid mine drainage that needs to be addressed by EPA prior to a full delisting of the site.

Archer will investigate this mine opening to see if it blocked. Is there a potential release of acid water? Is that water leeching into the creek? That will be the final piece once this current project is completed next year.Under EPA rules they return to monitor their work every five years.

STAC (Superior Technical Assistance Committee) was formed at the onset of the project many years ago. It is a group of concerned and caring citizens who have volunteered to work with all departments and organizations through the entire process.

Dr. Steve Ackerlund, Senior Scientist with Ackerlund, Inc., in Helena, has been the conduit and remains in this capacity.

“The Flat Creek cleanup will ultimately lead to better aquatic habitat locally and downstream, due to reduced sediment and contamination loads, but the benefits will take years to realize as the vegetation grows back, and the system re-stabilizes. Bob (Wintergerst) is making plans to present planned work at an upcoming county commissioners meeting,” he shares.

The bid process for the work will become available in May and Ackerlund strongly encourages local contractors to apply. This meeting, Friday, June 3, with the county commissioners will be for STAC members and the public to attend to hear firsthand of project dates, employment opportunities and the minor detours Flat Creek residents will be facing. He also added that this project has gone well in Superfund terms. It had funding from a settlement from ASARCO bankruptcy that allowed it to keep moving at the onset.