By Frank Munger
Sunday, December 18, 2011
OAK RIDGE — The exuberance of winning World War II — and playing a pivotal role — had barely died down when Oak Ridge received another secret assignment with national security on the line.
The Y-12 plant, which had enriched uranium for the atomic bomb dropped on Hiroshima, Japan, was asked to support development of lithium fuel for an arsenal of new super bombs.
These thermonuclear weapons would make the bombs that ended the war look like firecrackers, and they soon became the focus of a spiraling, ferocious arms race with the Soviet Union.
The Oak Ridge plant began the development work in 1950 and within a couple of years started experimenting with different processes to separate isotopes of lithium. The goal was to selectively concentrate the lighter lithium-6 isotope for use in fusion-type weapons, which became known as hydrogen bombs.
The lithium work was code-named "Alloy Development Program."
Most of the processes required the use of mercury, especially Colex (an abbreviation for "column exchange"), which proved to be the most successful. Some of the same big buildings that had been used for uranium enrichment during the Manhattan Project were converted to Colex production facilities.
Millions of pounds of mercury were essential to the project, according to a Y-12 report.
President Dwight Eisenhower signed the executive directives that allowed much of the nation's mercury reserves to be shipped to Oak Ridge in the 1950s.
Mercury is a slippery, elusive metal, and it wasn't contained very well at Y-12. Leaks were commonplace in the pipes that pumped mercury under pressure. There were system failures and waste discharges.
And there were big-time spills. According to documents posted on a Department of Labor website, there were five mercury spills between 1956 and 1966 at Alpha-4 and Alpha-5 — two of the Colex production facilities — that totaled between 285,500 and 500,000 pounds. One of those spills occurred in March 1966 during the removal of processing equipment from Alpha-5.
Plant reports and historical accounts indicate that Y-12 officials were highly aware of mercury's toxicity and took a number of precautions to limit workplace exposures to the metal, which vaporizes at warm temperatures and becomes a breathing hazard. Air sampling was used to evaluate conditions, and workers were reportedly taken out of mercury work areas if multiple tests of their urine showed they'd been overexposed.
Workplace health and safety standards weren't up to today's standards, but they undoubtedly got more emphasis than environmental protection in the 1950s and '60s.
East Fork Poplar Creek received the brunt of discharges. There are varying reports of how much mercury likely entered the creek, but it's estimated at somewhere between 240,000 and 280,000 pounds.
Oak Ridge Historian Bill Wilcox said the big releases of mercury were in the early part of the lithium project.
"The (Colex) plant started in 1955, and in 1958 we changed the process so that the amount was reduced down to a low amount," said Wilcox, who chaired a mercury task force put together by Union Carbide, the government contractor, in 1983.
"The Colex waste-handling was changed to reduce the amount of mercury (lost). We were worrying about it, it turns out, for economic reasons. So we changed the process and got most of that fixed."
Wilcox said it's important to realize that mercury in the environment wasn't considered a big deal in the United States until about 1970, after information spread about the disaster at Minimata, Japan, where thousands of people were affected by methylmercury from a chemical factory that poisoned the fish and shellfish supplies.
Rising concerns
Y-12's lithium project was a secret, as were other classified activities associated with production of nuclear weapons. Lithium processing was halted in 1963, after a glut of the bomb-making material had been stockpiled for future use. But it was another 20 years before the public became aware of the Y-12 work and mercury's large-scale presence in Oak Ridge.
In 1977, Oak Ridge National Laboratory scientist Jerry Elwood authored a report that noted elevated levels of mercury in Poplar Creek fish, and he recommended an investigation of upstream sources in East Fork Poplar Creek. But no action was taken and the report's distribution was limited to internal use.
In 1982, ORNL research biologist Steven Gough took unauthorized samples of vegetation in East Fork and sent them to his brother, who worked at the U.S. Geological Survey in Denver. The samples showed high levels of mercury. Gough left the lab in part, he said, because of the fuss his unapproved research created. While his information was not made public until the next year, it reportedly prompted a formal sampling in East Fork.
In November 1982, based on limited sampling but solid results, the state of Tennessee posted the East Fork Poplar Creek as a health hazard because of mercury pollution.
The news created a buzz of interest, and environmental regulators, including the U.S. Environmental Protection Agency, were starting to get tougher.
At the time, DOE officials said the mercury deposits in East Fork were probably the result of the 1966 spill of 100,000 pounds of mercury at Y-12.
The most shocking news, however, came on May 17, 1983, when the Department of Energy — responding to a Freedom of Information Act request from the Appalachian Observer, a weekly newspaper — released a declassified version of a document that gave a more realistic look at the pollution potential. The report stated that about 2.4 million pounds of mercury had been lost during the operations or was otherwise unaccounted for.
Some of the numbers were later refined and revised downward, but the impact of the mercury revelations was immense and long-lasting.
Suddenly, everything was questioned.
Why hadn't the government told Oak Ridge residents — or environmental regulators, for that matter — about the mercury pollution that unwittingly had been spread around town when the city dredged the creek for flood control and used the sediments as topsoil, even at school sites? What other environmental hazards were under wraps on the sprawling reservation that had been a heavily guarded enclave for nuclear research and production since the wartime Manhattan Project?
Congress wanted to know more, and U.S. Reps. Al Gore Jr. and Marilyn Lloyd, each of whom headed a subcommittee with interest in DOE and the environment, hosted a congressional field hearing in Oak Ridge.
The mercury revelations proved to be a springboard for further environmental investigations, not just at Oak Ridge but at Department of Energy operations around the country — including the Feed Materials Production Center at Fernald, Ohio, the Rocky Flats Plant in Colorado and many other sites.
The legacy of pollution from the government's World War II and Cold War work on nuclear weapons became a national scandal, resulting in the largest environmental cleanup program in U.S. history that's still going on today.
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