This area, also known as the 11-mile reach, can be seen from U.S. 24 south of Leadville near the Hayden Ranch. The work done in this area was the subject of a tour taken by the Lake County Open Space Initiative on Sept. 10. The issues in the area were caused by the mining operations on the east side of Leadville, according to Mike Holmes, project manager with the EPA. Waste from the mines would wash down the river and deposit along the riverbank, creating areas where no vegetation would grow. The goal of the project along the 11-mile reach is to remediate these fluvial tailings piles along the river.
This project is different than most remediation projects with the EPA, said Holmes. Part of the funding for this project came from a natural resource damages settlement that put money in a trust for state and federal agencies to use on habitat restoration. With this funding, for the first time, remediation is being done in conjunction with restoration, said Holmes. Usually the EPA does the remediation of mine waste, then Division of Wildlife or State Parks, for example, come in to restore the wildlife. Both were done this summer on the same project on the banks of the Arkansas River.
For the remediation, sugar beet pulp was used to neutralize the low pH, or acidity, of the soil. The pH of sugar beet pulp is 8, or basic, according to Holmes. There is calcium carbonate that releases over time in the pulp for a long-term remedy for the soil. Once this occurred, natural grasses and willows were transplanted to the river banks where there was no vegetation before. This will help in the restoration process as well, according to Nicole Vieira with the Colorado Division of Wildlife. This vegetation will make the banks more stable, especially with the unsteady releases from Turquoise Lake.
Another part of the restoration process was placing cross veins in the river. These are rows of boulders across the river that slow down the flow in specified areas. The river bed is excavated so that deep pools are created around the rocks for fish to live in the winter, she said. This will cut down on the amount of migrating in the winter to allow for healthier growth of fish, she said.
Meanwhile a new citizen advisory group is forming to oversee operable unit 6. Here’s a report from Ann E. Wibbenmeyer writing for the Leadville Herald Democrat. From the article:
According to Jennifer Lane, U.S. Environmental Protection Agency, Lake County Commissioner Mike Bordogna and Leadville Mayor Bud Elliott, the new CAG will be a completely different group than the existing group. Members of the existing citizens’ group are welcome to join the CAG, said Lane. Bordogna said that the two groups could work on parallel tracks. The difference, he said, is that the citizens’ group was appointed by the previous board of commissioners to advise the commissioners. This CAG would be set up under EPA guidelines, use EPA funds and advise the EPA.
The EPA is looking to cap more tailings piles in OU6, according to a report from Ann E. Wibbenmeyer writing for the Leadville Herald Democrat. From the article:
At a public meeting on Sept. 17, [Linda Kiefer, project manager for the U.S. Environmental Protection Agency] outlined the pilot study and the four methods being tested as possible remedies for the Greenback, RAM and Makato tailings piles in Stray Horse Gulch. These piles are visible both from the Mineral Belt Trail and East 5th Street, or CR 1. Under the original record of decision for remediating the operable unit 6 of the California Gulch Superfund site, there were two piles that were capped as part of the remedy. The rocks that were used to cover those piles changed the appearance of those historic tailings, which have since been referred to as “the wedding cakes” by Leadvillites ever since. The other part of this decision was to send other acidic runoff into the Leadville Mine Drainage Tunnel, which was supposed to be plugged to ensure that all the water would be treated in the plant run by the Bureau of Reclamation.
This brought the EPA to announce earlier this year that the remedy chosen in 2003 was not working, and it informed the Lake County commissioners that capping otherwise undisturbed piles was the next option. In 2003, this was an unpopular option, because the community wanted to preserve the history of those piles. The community still wants to preserve that history. The pilot study is an attempt to compromise by capping the piles, but making them blend into the other historic mine piles.
On one section of the test pile, shotcrete will be used as the capping material. This is a light concrete that is sprayed onto the pile. It can be done with various colorations, according to Kiefer. The section next to the concrete will be covered with inert rock and stabilized with timber cribbing, much like what is seen from the Mineral Belt Trail. The inert rock, which is non-acid producing waste rock from other piles, would retain the historic look of the piles…
The hope is that the construction of the test site will be done by the end of October, when the community will be invited on a field trip to see the outcome of the test pile.
More California Gulch coverage here.