Saturday, December 29, 2007

Question over waste remain

Desember 26, 2007

Mystery casks of highly radioactive material were found in October 2005

OAK RIDGE - In October 2005, cleanup workers made an astonishing discovery at a Cold War scrap yard west of the K-25 uranium-enrichment plant.

Three rusty casks containing thousands of curies of radioactive cesium-137 were found amid the mountainous piles of metal scrap.

Nobody knew where they came from. The old casks were unmarked, and the highly radioactive material did not fit the profile of other junk that came to the site in the 1950s and '60s.

There were plenty of questions and - more than two years later - they remain unanswered. If anything, officials are more tight-lipped than ever about the nuclear find.

Everything seems to be a secret, including the whereabouts of the casks.

"The location of the cesium casks is a security issue," said Dennis Hill, a spokesman for Bechtel Jacobs Co., the Department of Energy's cleanup manager in Oak Ridge. "However, they are in an approved secure storage facility and pose no threat to the community or the environment."

Cesium is a product of nuclear fission that emits beta and gamma radiation. It is used in cancer treatments and industrial instruments.

Cesium also is considered an optimum material for a radiological dispersal device - also called a dirty bomb - and thus coveted by terrorist groups. That probably explains why security is such a concern.

There have been varying estimates of how much cesium was actually housed in the lead-lined casks. A state official last year said he was told one of the casks contained more than 200,000 curies, although others downplayed that report and suggested it was more in the range of 10,000 curies.

Whatever the case, it was a staggering amount of cesium-137 to be sitting out in the rain.

For several months after the discovery, Bechtel Jacobs had to increase security at the scrap yard until a new home could be found for the casks.

Specialists at Oak Ridge National Laboratory were supposed to tap into the casks and fully characterize the contents, according to reports last year, but Hill said the analytical work has been postponed.

"The characterization is now scheduled for 2012," he said without further explanation. "Once (the casks) are characterized and it is determined where they can go, they will be disposed of."

The wrap-up work at the old scrap yard, known officially as the K-770 site, also has been put on hold.

Washington Safety Management Solutions completed the scrap removal at a cost of $16.3 million, but the soil at the site has be studied to determine contamination levels.

Hill said Remediation Services Inc. was conducting that survey, with a possible excavation of dirt to follow, but funding ran out. "The project has been pushed out to 2015 because of funding," he said.

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