The result, said Marv Hoyt, the Idaho director of the Greater Yellowstone Coalition, is that mining continues to leach selenium into streams and the aquifer - while 17 Superfund sites from past mining go untouched.
Lynn Ballard, spokesman for the Caribou-Targhee National Forest and BLM, denied there was any collusion with the mining industry to cover up the pollution.
"We've never operated that way," he said.
Mining for phosphate exposes rocks rich in selenium, which, once exposed to rain and snow, flows into streams and underground aquifers. It can build up in plants, reaching high concentrations that can kill livestock and wildlife and harm the people who eat them.
The Greater Yellowstone Coalition and Caribou Clean Water Partnership released a report written by a retired federal hydrologist, who pored over thousands of documents obtained from federal agencies through the Freedom of Information Act.
Edgar Imhoff, the hydrologist, during a press conference via telephone Thursday, said he was astounded by the toxic levels of selenium found as long as two decades ago in streams near phosphate mines north and east of Soda Springs.
"Given the dangers, the mining company and federal agencies had to be aware they had a serious problem on their hands," Imhoff said, referring to the owner of one of three active phosphate mines, Boise-based The J.R. Simplot Co.
Hoyt said the documents showed the federal agencies didn't just fumble their jobs. "This was something a lot more deliberate that just dropping the ball," he said.
The documents did not reveal secret deals, but rather a pattern of downplaying or obscuring the gravity of the pollution, Imhoff said.
He gave examples. Imhoff said in his report that data collected by the Forest Service's Intermountain Research Station in Logan in 1990 - it showed extremely high concentrations of selenium in surface water downstream from a mine - was not shared with the Environmental Protection Agency until 1997.
It was only after animals began dying that mining companies and federal agencies began acknowledging the pollution, casting it as a newly discovered problem, Hoyt said.
"People actually did know about this long before they say they did."
The Forest Service's Ballard said 1996 horse deaths prompted the Forest Service to "focus resources on a full investigation [of] what was causing the selenium impacts."
The agency also has required and received yearly water reports from Simplot, which opened the Smoky Canyon mine in the early 1980s.
He could not say whether the Forest Service considered selenium levels reported in those yearly documents as acceptable.
A Simplot spokesman could not be reached for comment.
The new report is aimed at preventing Simplot from expanding the Smoky Canyon mine near the Idaho-Wyoming state line.
A final environmental impact statement is due out within 30 to 45 days and is expected to endorse mining under certain conditions.
"There are mitigations placed in there that Simplot would have to do," Ballard said.
The environmental coalition also wants to light a fire under government agencies to force the owners of the 17 Superfund sites - including Simplot, whose Smoky Canyon mine has been declared a Superfund site - to clean up past messes.
kmoulton@sltrib.com
Phosphate, used in fertilizer and animal feed, has been mined in southern Idaho's Caribou County for a century. Three of 28 mines remain active. The open-pit mines produce $5 million in mineral royalties each year. Half goes to the federal treasury, 40 percent to Idaho schools and 10 percent to Caribou County. When phosphate is mined, selenium in rock is exposed and left behind in waste dumps, where it leaches into streams and groundwater. High concentrations of selenium have been recorded for years, but when six horses had to be euthanized in 1996 after eating selenium-contaminated forage, researchers began paying closer attention. Two more horses died the next year, and since then, more than 550 sheep have died from selenium contamination. Wildlife researchers blame selenium for mass salamander die-offs, deformed coot and Canada goose embryos and the deaths of animals such as beaver, cranes and pelicans. Fish are gone from two streams. Caribou County is home to the Grays Lake National Wildlife Refuge. Idaho health officials began warning in 2002 against children eating fish from one stream. Last year, health officials cautioned against eating the liver of elk killed near phosphate mines. Seventeen of the 28 mines have now been declared federal Superfund sites.
