GRAND JUNCTION — As Colorado nears the possible approval of the nation’s first new uranium mill in a quarter century, the federal government and state continue to deal with the staggeringly expensive and never- ending mess left by earlier mills.

More than a billion dollars has been spent cleaning up radioactive tailings piles and lessening toxic leaks into rivers and aquifers at nine defunct mills in Colorado. Nearly 20 million tons of radioactive tailings sit in disposal sites where they must be monitored in perpetuity. Hundreds of acres of unusable water fill contaminated aquifers.

Much has changed in the understanding of uranium milling since that toxic legacy was created. New regulations are in place to make the industry safer. But those regulations are still untested. Costs for dealing with its inevitable contamination are as long-lived as its radioactive leavings: The state’s latest regulations call for the monitoring of new mill waste for 1,000 years.

A full picture of all the taxpayer and privately funded expenses for past cleanup and ongoing monitoring and maintenance is not available because multiple agencies — the Department of Energy, the Nuclear Regulatory Commission and the Colorado Department of Public Health and Environment — along with multiple programs within those agencies, have a hand in overseeing the uranium legacy. The only federal cost information available is 5 years old.

Using those federal figures, The Denver Post found that, so far, the cleanup cost of mills in Colorado ranges from $50 million to $504 million per mill.

Nonetheless, the state is requiring that owners of the proposed new mill put up only $12 million in a bond for cleanup — an inadequate pittance in the opinion of mill opponents with an eye on history.

But supporters of the mill planned for the uranium-rich Uravan Mineral Belt in southwestern Colorado, as well as regulators, say they are confident modern milling will be different enough to make it a safe, viable industry that will not leave taxpayers saddled with cleanups costs.

If the mill’s application for a license is approved in January, rigid new safety requirements will result in less mess, they say.

“Colorado’s requirements for uranium recovery are specifically designed to avoid the mistakes of the past,” said Warren Smith with the Colorado Department of Public Health and Environment’s Radiation Program.

But not everyone is convinced.

“We need more cleanup before we even consider inviting this industry back in,” said Hilary White, director of the Sheep Mountain Alliance, a 22-year-old grassroots citizens group dedicated to preserving the environment of southwestern Colorado.

Wartime secrecy gone

One fact is clear: The climate surrounding uranium processing is much different than during the secretive era of the Atomic Energy Commission and the Manhattan Project. Mills then were popping up across the state to fill a frantic need for wartime and Cold War nuclear bombs.

The Piñon Ridge Mill that Energy Fuels Resources Corp. wants to build on 880 acres of the Paradox Valley instead would feed nuclear power plants, fill medicinal and other technological needs, and provide steel-hardening vanadium for industrial uses.

Unlike earlier mills approved with no consideration for their toxic legacy, Energy Fuels has handed over 15 thick binders to state regulators. The binders are filled with the design, environmental and safety details surrounding its proposed mill.

Regulators are examining hydrology, seismology, demographic impacts and effects on flora and fauna, as well as demanding complete plans for how the mill ultimately would be torn down and the site reclaimed.

This time around, overseers want to ensure radioactive dust won’t waft over Paradox Valley farm crops, chemical milling agents won’t harm wildlife, and heavy metals and radioactivity won’t trickle into water sources.

“We’re taking every precaution with this mill,” Smith said. “If the applicant can’t demonstrate they can conform to our regulations, they won’t get the license.”

In the past, mill owners weren’t required to clean up the detritus created by the crushing, leeching and drying of uranium ore into an enriched product known as yellowcake. As much as 99 percent of uranium ore is left as waste after the milling process. The finely crushed tailings still contain 85 percent of the ore’s radioactivity and heavy metals. It also contains milling reagents such as kerosene and ammonia.

That waste wasn’t considered a problem needing a solution until 1978, when the Uranium Mill Tailings Remediation Act passed. Only then were the 200 million tons of health-compromising tailings spread around milling and mine sites across the country suddenly dealt with.

In the heyday of uranium mining and milling, those tailings were simply piled along riverbanks or spread across unlined acres around the mills.

The hydro-intensive mills were allowed to set up shop alongside rivers. In some cases, the tailings were trucked to nearby towns to be used as fill dirt in construction projects.

The contamination left behind by all that, along with a more modern mess at the Cotter Corp. mill site near Cañon City, has cemented the idea of uranium milling as an environmental nightmare.

Cotter’s mill — the last to operate in the state — is in the process of being decommissioned after racking up nearly 100 violations in the past decade. It was declared a Superfund site in 1984, meaning that the government needed to step in and direct cleanup because the contamination was enough to pose a significant human health hazard. Cotter and the state are still wrangling over the cost and scope of that cleanup, which the health department estimates will add up to $20.8 million just for decontaminating the mill site.

A Superfund designation was also needed to get the Uravan mill and environs cleaned up. The $120 million cleanup there finally was completed two years ago — two decades after the mill shut down.

State legislators last spring passed the Uranium Processing Accountability Act, designed to prevent radioactive messes from sitting for decades. The act requires mills to clean up past contamination before beginning new processing jobs. It also gives the public a say in annual reviews of the amount of the financial bond that mill owners must post for potential cleanups.

A state regulatory change also addresses that issue. The state requires mills that are inactive for two years to start the cleanup process. In the past, mill owners left mills in “standby” indefinitely to avoid cleanup.

But those changes don’t satisfy White.

“Regulatory oversight is a mess,” White said. “The right hand doesn’t know what the left hand is doing. So we shouldn’t be rushing to do this (approve a new mill) when the proper regulatory oversight isn’t there.”

Travis Stills, managing attorney with the Energy Minerals Law Center, refers to that lack of clear information as “no data, no problem.” He said it undermines public confidence in the opening of a new mill.

“We don’t know where they are putting their effort. We don’t think adequate monitoring has really been there,” said Stills, whose organization is a nonprofit law firm based in Durango that focuses on protecting communities and the environment from impacts of energy development.

Monitoring costs $1 million

The state’s Radiation Program and the DOE’s Office of Legacy Management will spend about $1 million together for monitoring in Colorado in the coming year, according to DOE representative Christina Pennal.

Legacy Management site operations director Ray Pleiness said his office doesn’t break out the ongoing costs for each of the cleaned-up mill sites in Colorado.

New-mill proponents point to cheerier numbers. Mining industry research on the economic effects of Energy Fuels’ proposed $150 million mill show it could create 85 well-paying mill jobs and about 500 related jobs in construction, retail and mining.

Frank Filas, environmental manager for Energy Fuels, said he thinks, in addition to the economic boost of a new mill, his company can prove uranium milling can be done in “a more environmentally sensitive manner.”

That will mean triple liners for tailings impoundments, leak detectors, dust dampeners and a closed vacuum system for drying yellowcake. And, just in case, that $12 million bond and 1,000 years to keep an eye on the waste.

Nancy Lofholm: 970-256-1957 or nlofholm@denverpost.com

MAYBELL MILL AND DISPOSAL SITE

$63.5 million Cost of cleanup The Union Carbide Corp., now Umetco, and a subsidiary contracted with the Atomic Energy Commission to operate a mill 5 miles northeast of Maybell between 1957 and 1964. The mill processed about 2.6 million tons of ore and uranium-laced slimes and slurries through milling and leaching before the mill closed.

Left behind: 2.6 million tons of tailings spread over 80 acres. Discharges of as much as 400,000 pounds of tailings during the 1960s resulted in water contamination 3 miles downstream of the mill.

The fix: Umetco dismantled the mill and began stabilizing tailings in 1971. DOE did surface cleanup from 1995 through 1998 and placed 3.5 million tons of contaminated materials in a 66-acre disposal cell.

NATURITA MILL AND DISPOSAL SITE

$86.3 million Cost of cleanup The Vanadium Corp. of America began operating the mill in 1939. The mill processed 704,000 tons of uranium ore for the Manhattan Project from 1942 to 1958. In the late 1970s, a private corporation bought the tailings pile and moved it to another site called Hecla/Durita to extract additional uranium and vanadium.

Left behind: At and around the original mill, 138 acres were contaminated. Groundwater beneath the site was contaminated.

The fix: From 1993 to 1997, DOE removed 800,000 yards of contaminated material and put it in a disposal site near Uravan. Contamination was left in place on 22 acres. More than one acre was left because the radiation levels were so high that workers would have been at risk.

RIFLE OLD AND NEW MILL AND DISPOSAL SITE

$119.1 million Cost of cleanup The old mill site just east of Rifle was built by the Standard Chemical Co. in 1924 and operated until 1932. Union Carbide reactivated the mill in 1942 and began milling and leaching uranium from ore for the Atomic Energy Commission until 1957.

A quarter of a million tons of tailings were moved to the new mill site southwest of Rifle that began operation in 1958 and closed in 1984.

Left behind: Tailings stacked 33 feet high and covering 13 acres were left at the old mill. Groundwater under both mills was contaminated. Contaminated water seeps into the Colorado River, where it is dissipated by natural flow.

The fix: Union Carbide covered 2.7 million tons of tailings at the new site with soil and vegetation. The pile was eventually eroded by wind and water. DOE cleaned up the tailings and other hazardous materials from 1988 through 1996, relocating 3.8 million cubic yards of radioactive materials to a cell 6 miles north of Rifle. Contaminated materials were removed from another 113 properties in the vicinity of the mill.

SLICK ROCK AND SLICK ROCK EAST AND WEST MILL AND DISPOSAL SITE

$50.43 million Cost of cleanup The Shattuck Chemical Co. built the east mill 2 miles north of Slick Rock in 1931 to extract radium salts and vanadium from ore. In 1945 the federal government took control of the mill to supply uranium for the Manhattan Project. Union Carbide bought the mill in 1957 and closed it in the early 1960s. The west mill — also called a concentrator — began operation in 1957 and closed in 1961.

Left behind: A 19-acre tailings pile located at one point just 35 feet from the Dolores River. Groundwater was contaminated in an underwater plume that covers about 19 acres at one site and 92 acres at the other.

The fix: DOE did surface cleanup at the sites in 1995 and by 1999 had materials in a cell. About 857,000 cubic yards of radioactive tailings were removed to the disposal cell from this site.

Source: Department of Energy Office of Legacy Management and U.S. Energy Information Administration. Photo: Penelope Purdy, Denver Post file