A recent Denver Post article is being called misleading and inaccurate for overstating the risks to wildlife from mine contamination around a Superfund site near Silverton.
“The statement that EPA crews found that lead is threatening birds and animals is not accurate,” Environmental Protection Agency project manager Rebecca Thomas wrote in an email Friday. “The terrestrial risk assessment is ongoing and no conclusions have been reached.”
Around 7 p.m. Thursday, The Denver Post sent a “Breaking News Alert” for a story titled “EPA crews working on Gold King cleanup find elevated lead threatening birds, animals and, potentially, people.”
In the story, the Post draws the conclusion based on a presentation the EPA gave Monday, in which the agency said preliminary sampling of soils around the Superfund site found levels of lead at some locations at 5,000 parts per million.
The Post said these levels are 100 times higher than “danger thresholds for wildlife.”
However, EPA had said this data had not been validated.
“The statement regarding ‘danger thresholds’ for wildlife in The Denver Post story is misleading,” Thomas said. “At this point, we are looking at very conservative screening values in assessing potential risk.”
San Juan County Commissioner Scott Fetchenheir, a former miner and geologist who is quoted in the Post article, also took issue with the story.
“I tried to explain that to (the reporter) and he just didn’t get it,” Fetchenheir said. “He had his mind made up there’s going to be lead problems.”
Attempts to reach the Post late Friday were not successful.
On Monday, the EPA told a crowd of about 30 people at Silverton’s Town Hall that a study of soils in the Bonita Peak Mining District Superfund site, which consists of 48 mining-related sites, found elevated levels of lead and zinc.
Out of 35 mine sites, nearly 90 percent ranked in a “high risk” category. Nearly half of 25 over-bank soil areas (sediment near rivers) and three out of 12 campsites were tagged in the “high risk” category.
However, Brian Sanchez, an EPA ecotoxicologist, said the rankings were somewhat “arbitrary” and are mainly used as a framework for the agency as it drafts a more complete priority list of sites it wants to address.
“As a point of reference, these risk assessments are part of a larger site-wide remedial investigation that will be used to help us identify where response actions may need to be taken,” Thomas said.
Those studies are expected to take some time to complete. Thomas said a human health risk study should be done by the end of the year and a water quality report should be released sometime in spring 2018.
The report the Post based its recent article on isn’t supposed to be finished until 2019.
Thomas said that it’s not unexpected that waste-rock piles and mine tailings that were tested showed high levels of lead. The “5,000 ppm” figure quoted in the Post story, for instance, was located immediately adjacent to a waste-rock pile, she said.
“These piles make up a very small percentage of the total area within the 150-square-mile BPMD, and the piles themselves do not provide attractive habitat for most wildlife,” she said. “Again, no conclusions have yet been drawn related to the impacts of waste piles nor the surrounding halo areas.”
Mining began in Silverton in the late 1800s. Fetchenheir, a longtime Silverton resident who has been involved with the cleanup of legacy mining for years, said there’s never been evidence animals have been affected.
The Post’s story said lead and other contaminates can be “absorbed by plants, then ingested by bugs and transferred from the insect to birds to, ultimately, mammals.”
“It’s ridiculous,” he said. “I’ve never seen dead animals because of lead poisoning.”
The EPA, however, includes studies on soils and potential human health risk as a matter of course in the early stages of a Superfund listing. Issues surrounding the Bonita Peak Mining District, which was declared last fall, have historically revolved around water quality issues.
Matt Thorpe, a wildlife manager for Colorado Parks and Wildlife based in Durango, said most concerns are centered on the fisheries as a result of poor water quality, largely associated with pollution from past mining activity.
As for mining contamination affecting wildlife, “No, I’m not aware of any concerns,” Thorpe said.