The Superior Technical Assistance Committee continues to meet regarding the Flat Creek Iron Mountain Mine EPA Superfund project located north of Superior. The work on the $3.5 million project is nearing completion and on Aug. 7 the committee met in Superior where erosion from the spring flooding on Flat Creek was discussed. Flooding damaged the newly planted vegetation and made the stream bank unstable causing the stream to braid into other areas according to Bob Wintergerst with the U.S. Forest Service.
However, the runoff was backfill soil and not contaminated mine tailings said Joel Chavez, construction manager with the Department of Environmental Quality (DEQ). Although there is not enough money to completely return the creek to its former state prior to the flooding, the braided channels will be closed off and other work will be done to restore and stabilize the creek. Chavez stated that the legal document used to guide the project, the Action Memorandum, does not allow work in the actual stream bed.
The forest service hydroseeded the bare areas along the creek and will continue to work with DEQ to develop a long-term stream bank stabilization plan as well as a tailings Removal Action Plan on forest service property.
One concept for future action includes removing some trees to access additional mine tailings. The timber would then be used for stream bank stabilization. They will also use a variety of local seed for more diverse vegetation and help to enhance the recovery of the area to its natural conditions.
There are also plans to construct a new 2,600-cubic-yard repository cell near the current Wood Gulch Repository located in the area. This would allow for possible future use if additional mine waste is identified. More tailings removal work is scheduled for 2019. Bids for a contractor to do the work will be awarded on Aug. 23 with work starting in September.
Although not a part of the Superfund project, another portion of the cleanup effort is to find an alternative drinking water supply which is the emergency backup water for Superior. Because the shallow ground water in the Flat Creek area has antimony which exceeds the Safe Drinking Water Act several test wells have been drilled by local contractor, Will Callison.
As a result, the mouth of the Club Gulch has been identified as the best area to provide enough clean drinking water for the town. Additional water testing will be done and the results should be available later this month. Funding for the new well is yet to be determined. However, officials at the meeting said there are various state and federal programs that provide support for rural water development. Technical Advisor Steve Ackerlund also pointed out that there are low-cost ion exchange systems that can be designed to remove antimony from the water.
The next steps in the cleanup include a five-year review of the Superfund remedy which is due to be released by the end of September. There is also some funding available to begin preparation for a work plan to investigate the ongoing release of contaminated water from the mine adit and other mining activity on the historic Stimpson mine claim located further up on the drainage area. Other projects, such as the additional site investigation and monitoring of Flat Creek, will rely on the availability of funds which will be applied for by Allie Archer with the Environmental Protection Agency.
The Superfund site was contaminated by the 1888 Iron Mountain Mine which continued to operate throughout the 1900s producing primarily lead, zinc, and copper. The water and soil was found to contain arsenic, mercury, and antimony. In all, more than 90,000 cubic yards of contaminated tailings have been hauled to the repository as a result of the Superfund project.