by Mark Reaman
The accidental spill from a holding pond at the Standard Mine reclamation project west of Crested Butte is not expected to have any negative impact on the town’s drinking water. The spill occurred late Wednesday and is believed to have involved approximately 2,000 gallons of water and gray-colored sentiment.
The town issued a press release Thursday afternoon stating that the Environmental Protection Agency (EPA) notified them of the accident Wednesday evening. The town was told that a contractor had been dewatering the pond “containing un-mineralized sediment from drilling operations and water from the lower mine adit. The contents had been treated to a neutral PH of 7. The treated water from the pond was being discharged into Elk Creek as part of a planned maintenance activity. A vacuum truck siphoning clear water from the surface of the pond accidentally dipped into gray-colored sentiment leading to the accidental discharge of sediment and gray-colored water into Elk Creek. The discharged material contained a mixture of PH-neutral rock slurry and water from the mine.”
In a statement from the EPA headlined “Standard Mine Vacuum Truck Release”, the agency said local and state governments were notified right away. “EPA immediately notified the Town of Crested Butte water treatment plant and called the Colorado Department of Public Health and Environment spill hotline that an EPA contractor dewatering a sediment pond into Elk Creek at the Standard Mine Superfund Site released an estimated 2,000 gallons of water and sediment into nearby Elk Creek,” the statement relayed.
“Based on the neutral pH levels, the quantity of water released, and flow levels downstream in Coal Creek, the Town of Crested Butte did not close its water intakes. Subsequent investigation found no visible plume or signs of significant impacts in downstream locations. All work on the sediment pond is complete. The EPA continues to coordinate closely with Crested Butte officials on this matter.”
The town’s statement on the matter explained that based on the size and content of the spilled material, the flow levels downstream and the 10-million gallon storage reservoir at the Crested Butte treatment plant, “the Town Department of Public Works has determined that any impact to the town’s drinking water would be negligible.”
According to the EPA, the pond was constructed to retain sediment, pulverized un-mineralized rock from drilling operations, and water discharged from the lower mine adit. The water contained in the sediment pond had been treated to reduce acidity to neutral pH levels and was being discharged to Elk Creek as part of planned maintenance activity at the site. The release occurred when a vacuum truck siphoning water from the surface of the pond dipped too low and siphoned sediment material from the bottom of the pond, leading to the discharge of the sediment and grey-colored water to Elk Creek. The material released to the creek contained a mixture of pH-neutral pulverized rock slurry and water from the mine.
The town has hired an independent contractor to perform testing to ensure that there is no negative impact to the Town watershed or drinking water. The town and EPA are working together on the follow-up to the accident.
We will have more information on the incident in the October 16 issue of the Crested Butte News.