Reclamation efforts continuing at Standard Mine

Contaminated water treatment considered

New information obtained through two recently completed studies may help with reclamation efforts at the Standard Mine and allow the Environmental Protection Agency (EPA) to treat less contaminated water from the mine, officials told the Standard Mine Advisory Group (SMAG) at a meeting in December.

 

 

 

The Standard Mine is an abandoned mine that encompasses 10 acres in the Gunnison National Forest west of Crested Butte. In 2005, the EPA designated it as a Superfund clean-up site after confirming that arsenic, barium, lead, zinc, cadmium, copper and chromium appeared at three times their ordinary levels in Elk Creek below the mine site.
The Standard Mine Advisory Group (SMAG) has been monitoring the EPA’s progress and has provided a forum for the community to participate in the decision-making process in cleaning up the site.
According to EPA Superfund project manager Christina Progess, the purpose of the meeting was to provide information from two investigations conducted in 2006 regarding water flow and contamination within the mine.
Andy Manning from the United States Geological Survey (USGS) and Steven Renner with the Colorado Division of Reclamation and Mining Safety presented their findings from the Underground Mine Workings Assessment and Hydrogeology Investigation during the meeting.
Anthony Poponi, executive director of the Coal Creek Watershed Coalition, a non-profit watershed organization that monitors the Superfund process, says the information gathered from the investigations may assist with future clean up efforts.
“It’s just another piece of the puzzle in characterizing the contaminants at the mine site and possible remediation,” Poponi says.
Poponi says past efforts by the EPA have addressed contamination on-site, but the new information will assist with dealing with drainage into the mine.
Progess says researchers were tasked with reviewing the geology of the mine to determine how water is getting into the mine and to see if fractures are allowing the seepage. She says they also looked at the structural integrity of the workings of the mine, and mapped the geology of any fractures.
Progess says the report found that water flows more through the fault and in from the roof of the tunnels than through fractures.
“The report told us how ground water incepts the mine workings and we found that the fault is the main conduit for the water. Our focus now is how to keep water out of the fault,” Progess says.
Manning says the information will help the EPA to reduce the amount of metals in the water by developing a strategy that will prevent water from entering the mine in the first place. Manning says one strategy is to remove or divert the water from the fault before it travels through the portion containing the ore.
Poponi says another idea involves sealing the fractures or fault with concrete to reduce the amount of water coming into the mine; however, he notes no final decisions have been made as of yet.
Progess adds, “The report’s information will help us (develop) a final remedy as to how to minimize the amount of water flowing through the mine that we will have to treat,” noting the reports have not been finalized as of yet.
As for the hydrogeology investigation, Progess says researchers took samples of water from in the mine and outside the mine to determine where the water is being contaminated and to figure out the age of the water.
Progess says it’s important to know how water moves through the mine and how old the water is in order to determine the potential for a “blow out.” A blow out is when water pools in the mine and causes the mine to collapse, surging the water outside of the mine. A surge of water is of particular concern, Progress says, because it could be damaging to nearby waterways.
“There is no mine pool to be worried about,” Progess adds.
According to Manning, the report found that the water is very young, generally less than one year old, which means the ground water gets flushed through the mine on a seasonal basis.
The investigations also tried to determine where contamination is occurring within the mine. Manning says that although the researchers were not able to specifically identify the main source, they were able to narrow down where they think the contamination is occurring. However, Manning says future work is needed to make a final conclusion.
“We hope to go back into the mine and reach the lower levels where we think the source rock is and sample the water down there, we weren’t able to do that initially because they are collapsed,” Manning says.
Steve Glazer, High Country Citizens’ Alliance water director and coordinator for SMAG, says the planned additional investigation sounds very dangerous, but could be the most productive. The mine has five levels, but several are inaccessible. The researchers were able to access only about 80 feet into level one and were unable access level 2 at all because of the unsafe situation.
“Hopefully we can access level 2 next summer, and find a way to reduce the flow coming out of the mountain, by reducing the loading it can make the treatment (remediation) a lot easier, and less expensive,” Glazer says of the work scheduled for next spring.
According to Glazer, it was originally believed a remediation plan would be created within a year of the SuperFund designation. However, next summer will mark three years for the project. Glazer says a remediation plan is still a year or two away.
“We are gaining a lot better understanding of what’s going on (in the mine) and we are looking forward to further investigation. Everyone is online that further investigation is needed before remediation goes forward,” Glazer says.
Progess says the EPA plans to work with the USGS and the Division of Reclamation and Mining Safety this spring to conduct further analysis.
Earlier studies conducted by the EPA found that a leaky tailings pond at the mine was the culprit at-blame for contaminants found in Elk Creek, and work began last summer to drain the pond and stabilize the area surrounding the mine to begin containing contaminants.
A series of ditches, rock channels, culverts and berms were constructed throughout the site to begin diverting water runoff from Elk Creek. The tailings pond was also drained, filtered, and pumped free of water.
In July, contractors began removing waste rock and tailings to a staging area near the tailings impoundment dam. That waste will later be hauled to the repository area, where approximately 80,000 cubic yards of waste will be permanently stored. The repository is located on the eastern side of Elk Creek Valley and is heavily wooded, although tree removal also began in July to prepare the site for waste storage.
The meeting also touched on the efforts of removing waste rock. Glazer says he was impressed by the update and says it shows the importance of removing waste rock.
“We’ve spent the last two summers getting rid of the waste rock at the lower levels, so based on the information we’ve seen, there is good reason to hope Elk Creek metals will show significant improvements,” Glazer said. “This shows how important it is for us there is no waste rock left on the surface and it has implications for the Lucky Jack proposal.”

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