N-Waste May Be Flowing Toward Columbia Leaked Radioactive Material At Hanford Moves Farther, May Be In Groundwater

Nuclear waste has leaked out of the giant underground tanks at the Hanford nuclear reservation here and flowed deeply into the soil, and some experts are convinced that it has reached underground water supplies and is flowing toward the Columbia River.

For years, the Energy Department argued that any radioactive material that leaked would be chemically bound to the soil and would not flow, but recent measurements show that cesium and other materials have moved farther than expected. A group of outside experts brought in by the Energy Department said in January that the model the department had used to calculate the spread of underground materials was “inadequate and unrealistic.”

The experts’ report said that migration of radioactive cesium through the dirt “does not necessarily indicate an immediate health risk to the surrounding population,” but it added that the implications for a cleanup were immense.

The department has been trying to reduce the possibility of future leaks by pumping liquids out of the 28 oldest tanks, emptying about five each year for the last few years. But in the fiscal year that began Oct. 1, the plan is to begin pumping only two, because of budget constraints. The delay horrifies some environmental experts.

The tanks, some with a capacity of up to 1 million gallons, were built in haste and buried at the Hanford reservation during the Manhattan Project, the World War II effort to build the atomic bomb, and the Cold War. The tanks hold half a century’s worth of highly radioactive and poisonous byproducts of nuclear weapons production. The liquids, solids and sludges are a complex mixture of materials created in military reactors, and various chemicals that were used to recover uranium and plutonium from that reactor fuel.

If leaks from the tanks reach the Columbia River through ground water, radioactive material would eventually be incorporated into the food chain and could expose people to radiation for centuries.

The government has always had vague plans to convert the wastes into some other material that would be safer for long-term storage. Now, officials say, a plan for a permanent form of disposal is taking shape that would contain the radioactive material in glass. But that plan has raised a new question - how to scrape the sludges and salts out of tanks that are already leaking. The standard method is high-pressure water jets, but that could cause new leaks.

The disposal system involves binding the wastes into logs of glass, inside stainless steel canisters. This is already being done at a nuclear bomb plant in South Carolina.

The effort to build a glass plant has moved forward only in fits and starts. This is the third effort to build one; the first two failed.

In the dirt under the tanks are two of the radioactive elements that are formed when plutonium is produced, technetium 99 and strontium 90.

“Our tank waste is now in the ground water and is moving into the river,” said Casey Ruud, a safety analyst at the state of Washington’s Department of Ecology, who formerly worked for the Energy Department and for contractors at the site. Ruud won awards for revealing problems in plutonium processing at the site in the 1980s.

“They said for years that no tank waste would reach the ground water,” he said. But it is there now and may reach the river in 20 years, he said. The waste, he said, is “the worst stuff in the world.”

John Wagoner, the chief of the Energy Department field office here, said that about 100 square miles of the 560-square-mile site had water contaminated above federal standards for drinking water, but that the source of the contamination under the tank farms was not clear; it could have come from spills at the surface, or from places elsewhere on the site where, in the rush to build bombs, processing plants dumped waste directly into the dirt. But Ruud said that new equipment, which could identify how much of each radioactive material was present, had shown that the ratio of pollutants in the dirt matched the ratio in the tanks.

There are 147 single-shelled tanks here. The Energy Department says 67 have leaked; the state thinks the number is 69. The problem could be limited because most of what is in the tanks is solids, and 119 of the tanks have been emptied of liquids by workers.

But the Lockheed Martin Hanford Corp., a contractor that operates the tank farms, plans to start pumping only two more in the next 12 months. James Wicks, a company official who was in charge of the tank farms for three years, said the reason was that budgets for the tanks have fallen from $450 million in 1994 to $308 million this year, and staff has been cut 40 percent.

“We’re talking about taking a year off” from pumping, Wicks said, “to see if we can reduce the cost of how much it takes to pump a tank.”

Some tanks have only a few thousand gallons of liquids in them, some have hundreds of thousands.

Of approximately 55 million gallons of waste, mostly sludges and salts, about a million gallons of liquids has leaked. But that was not the most intensely radioactive material; 99.4 percent of the radiation remains in the tanks, the department estimated.

Wagoner said the question of whether the tanks have leaked into the ground water would be expensive to answer, and thus might have to wait for more pressing engineering questions.

Engineers could end up digging wells to pump contaminated water out of the ground and then cleaning it up and re-injecting it. They have already built such systems to capture chemical pollutants here.

But others think the problem is urgent. Tom Carpenter, a lawyer with the Government Accountability Project who represents workers at bomb plants who say they have been fired or demoted for raising safety questions, said that tank wastes in the soil were “the single biggest long-term environmental threat at Hanford and to the Northwest.”

“I look at it as slow-motion fallout,” Carpenter said. “Once it’s in the ground water, it’ll be almost impossible to retrieve it.”

There is progress on the likely long-term solution, a glass factory. The Energy Department has requested bids from private entities to build two such factories, and is hoping to sign two such contracts, with British Nuclear Fuels and a consortium led by Lockheed Martin that includes Cogema, a French company. Both European groups regularly put waste in glass, although their wastes are chemically simpler than the ones at Hanford. At the earliest, a plant could not be completed before 2002.

A glass factory at another plutonium-producing plant, the Savannah River Site, near Aiken, S.C., opened only after long delays and has had production problems.

The problem of getting waste out of the tanks seems to grow more complicated over time. Experts here recently discovered that pockets of hydrogen can build up within the solids in the tank. Hydrogen is an explosive gas that is a byproduct of the interaction of high radiation fields on other chemicals. Now, to sample wastes from low down in the tanks, technicians sometimes pump in inert nitrogen gas to preclude an explosion.