Metalli radioattivi: da Oak Ridge riciclate 500 tonnellate, perlopiù acciaio (29 agosto)

More than 1 million pounds of material from K-25 Site being reused

August 29, 1999

By Frank Munger, News-Sentinel Oak Ridge bureau

OAK RIDGE -- Contamination at the K-25 Site continues to draw controversy, but that hasn't slowed government contractors who are recycling tons of radioactive scrap metal taken from the Oak Ridge plant.

Since BNFL Inc. -- the American subsidiary of British Nuclear Fuels -- began its cleanup operations last year at the former K-25 uranium-enrichment plant, about 1.8 million pounds of contaminated metal has been removed from buildings there. More than a million pounds already has been decontaminated and sold to commercial foundries. Much more will hit the market in the next few years.

The U.S. Department of Energy endorses the recycling effort as an integral part of BNFL's $238 million cleanup contract, and federal officials insist the activities are safe and well-monitored.

"The alternative to not recycling the material is to bury it in the ground," said Robert Brown, DOE's assets manager.

The Oak Ridge program, however, has attracted national attention, much of it negative.

Critics claim that recycled metals could unwittingly expose people across America to small amounts of radioactivity in everyday products.

Locally, the clamor has been about worker safety.

An Oak Ridge union contested the BNFL project from the beginning, and some former employees at K-25 say they're afraid the recycling of metals will expose a new generation of workers to the same hazards that made Cold War personnel sick.

"I think that's something that disturbs people," said Janet Michel of the Coalition for a Healthy Environment. "We haven't had a lot of information on this project."

Manufacturing Sciences Corp., an Oak Ridge company purchased by BNFL a couple of years ago, is processing the radioactive scrap.

MSC President Jim McAnally, who recently assumed responsibility for all of BNFL's Oak Ridge operations, said people shouldn't be worried.  "I've been in this business all my career, and in my opinion there is absolutely no danger to public health in this material," he said.

Mike Mobley, the state's director of radiological health who regulates commercial nuclear operations, said MSC's recycling plans were evaluated closely before any licenses were issued.

Mobley bristles at suggestions that Tennessee authorities may have been lax in protecting public safety, as activists have claimed.

The amount of radioactivity that remains after the metals have been decontaminated is insignificant, Mobley said.

BNFL's contract with DOE calls for it to clean up three huge buildings at K-25, housing many miles of piping, converters and other equipment once used to process uranium for atomic bombs and nuclear reactor fuel.

The company and its contractors are dismantling the uranium operation, which was shut down in 1985, and salvaging materials worth recycling.

Metals too difficult or too expensive to recycle are handled as radioactive waste and sent to disposal facilities.

The bulk of the metal recycled so far has been carbon steel with some radioactivity -- primarily uranium -- on the surface. MSC uses a dry process known as "grit blasting" to abrade the surface and remove the contamination.

Afterward, the metal pieces are surveyed across their entire surface to ensure that radiation levels are below those limits for unrestricted release.

More controversial is a future plan to recycle about 5,000 tons of nickel that's being retrieved from classified components in the uranium-enrichment system at K-25.

The nickel was part of the "barrier" that separated the different isotopes of uranium and concentrated the fissile U-235.

BNFL and its contractors cannot take ownership of the nickel until the classified shapes of the barrier have been destroyed.

Therefore, the material must be melted down to meet national security requirements.

The presence of radioactive technetium in the nickel poses another obstacle and concern. MSC has tested a modified electro-refining process to remove the nuclear contaminants from the nickel.

The state has approved MSC's license for processing and reselling the nickel, much to the displeasure of dozens of environmental groups and even some members of Congress, such as U.S. Reps. John Dingell, D-Mich., and Ron Klink, D-Pa.

Some of the nickel melting may take place as early as November, but the processing effort isn't scheduled to begin in earnest for another year.

The problem, according to critics, is that melting will distribute the radioactive contamination throughout the metal -- making it impossible to simply scrape it off or blast it away.

In addition, there is no established release standard for materials that have "volumetric" contamination, and thus Mobley and his staff formulated one after evaluating MSC's decontamination plans and studying release standards in other countries where smelting of radioactive metals takes place.

The state official said he is somewhat surprised by the furor over the nickel plans because he was cautious in establishing the release limits.

He said the amount of radioactivity in the nickel will be less than what's allowed for materials with surface contamination.

Mobley said this is not the first time he has set a standard for volumetric contamination. He said he did so a few years ago for a metal-recycling project at Scientific Ecology Group, an Oak Ridge company now owned by GTS Duratek.

Activist groups have appealed to the Clinton administration to halt the Oak Ridge recycling effort until an environmental impact study has been done.

Dingell and Klink complained to the U.S. Nuclear Regulatory Commission that Tennessee in essence is setting a de facto national standard for release of materials with internal contamination, despite the historic controversy.

Tennessee is a so-called "agreement state," which means it regulates commercial nuclear facilities under an agreement with the U.S. Nuclear Regulatory Commission.

"At some point," Mobley said, "you just have to make a determination of when (to release) something that is so minimally contaminated. Because everything is contaminated at some level, whether people want to believe that or not."

David Hackett, an engineer who formerly worked at K-25, said he would be more at ease if DOE and its contractors had consistently lived up to standards.

But history, Hackett said, has shown that not to be the case.

Hackett also said there's no apparent plan to track the whereabouts of metals after they're sold or to restrict any of the future uses, even if that means making baby bracelets with radioactive metal.

While about a million pounds of radioactive metal has been cleaned up at MSC's facilities and then sold to commercial foundries, an equal amount of scrap has been surveyed and sold to dealers directly from the K-25 Site because it was deemed to be uncontaminated.

The U.S. Department of Energy hired a contractor -- the Oak Ridge Institute for Science and Education -- to monitor operations at the BNFL cleanup project and independently verify that metals released from the site were not contaminated.

The independent verification team has found problems on at least a couple of occasions, including a November 1998 incident in which some contaminated copper pipe was mistakenly placed in a clean bin about to be shipped off-site.

Although records indicated the materials were uncontaminated, "The IVT discovered, by visual inspection, droplets of yellowish liquid which appeared to be uranium oxide," a report on the incident states.

The pipe contained enriched uranium, with radiation readings that clearly exceeded standards.

Eric Albequist of ORISE said the verification team has found only a couple of contamination problems among thousands of items approved for release.

"There are always going to be mistakes," he said.

"But the overall success of the program is unquestioned."

Undetected mistakes, of course, could have allowed contaminated metals to be released to commercial vendors.

McAnally said investigators have looked into various reports of tainted shipments.

"We didn't substantiate a single allegation," he said.

Following the November 1998 incident, however, BNFL tightened release standards and no longer assumes any metal pipe is uncontaminated based on its prior use, McAnally said.

Frank Munger may be reached at 423-482-9213 or