Hanford Spill Traced to Vulnerable Water Line

By Michael Milstein, The Oregonian, Portland, Ore.

Aug. 1–Federal officials traced a spill of highly radioactive waste at the Hanford Nuclear Reservation last week to a water line that was never intended to handle such a hazardous brew and delayed detection for hours.

Attempts to unclog a pump plugged by nuclear waste as thick as chunky peanut butter inadvertently forced the sludge from an aging underground tank into the water line, which sprung a leak, spilling 50 to 100 gallons onto the ground, said Delmar Noyes of the U.S. Department of Energy.

“This water line was never designed to contain or have waste injected into it,” he said during a telephone conference call with reporters.

It was the worst spill at Hanford in recent years as federal workers and hired contractors try to empty 149 deteriorating underground tanks filled with waste from the dawn of the nuclear age. Nearly half are suspected of leaking.

Only seven tanks have been emptied.

Review teams are trying to figure out how to clean up the spilled waste. They also want to know how the radioactive and chemical waste entered the water line, which was not double-walled such as the hoses meant to carry the material.

The line also lacked leak sensors that would have immediately alerted workers to the spill.

Instead, workers discovered the leak seven hours later, after monitors detected high levels of radiation in the area, Noyes said. Once officials realized waste had spilled, Hanford employees were told to stay inside nearby buildings.

Public notices were issued about nine hours after the spill.

No one was injured or exposed to harmful levels of radiation, and there was never any risk to the public, officials said. The small area of saturated ground was sprayed with a sealant to prevent the wind from blowing any radioactive material.

Officials suspended pumping from another tank until they review the spill and understand why it happened.

Critics said the spill raises serious questions of whether officials overseeing Hanford’s multibillion dollar cleanup have thought through the way things might go wrong.

“You should be thinking about all the ramifications before you start a new process,” said Natalie Troyer of Heart of America Northwest, a Hanford watchdog group.

The spill occurred as crews dealt with a tank of radioactive sludge left from the earliest days of the Manhattan Project, the secretive World War II drive to build the world’s first nuclear bomb.

Teams began emptying the tank in 2004, moving its contents to a more secure, double-walled tank. But the sludge inside has proven unusually stubborn because it is so thick.

“It’s particularly rough on pumps,” said Richard Raymond, of CH2M Hill Hanford Group Inc., the contractor hired to clean up the tanks.

The sludge has repeatedly crippled pumps that have broken down and been replaced, and teams developed new methods to break up the sludge so the pump could move it more easily. One is a tool called the “Rotary Viper,” which churns the sludge with a high pressure water spray.

The pump was replaced again this month, with a slightly different configuration that cleanup crews hoped would make it less likely to clog. A pipeline feeds water into the tank to dilute the sludge so the pump can move it more easily.

Last Thursday night the pump clogged again. Workers followed their normal procedure of reversing the pump’s flow and restarting it in hopes of clearing the clog.

But when they reversed the flow about 2:10 a.m. Friday, the maneuver drove nuclear waste up the water line alongside the pump intake and out of the tank, where it spilled out onto the ground, Noyes said. A regular safety check of the area detected high radiation levels, which is not by itself a sign of trouble, but led to further checks.

A team clad in protective gear found the spill about 9:45 a.m.

The lag time was necessary to make sure crews were properly briefed and outfitted before they entered the area to look for problems, said Mark Brown, director of tank farm operations for the Department of Energy.

“It takes some time to plan for worker safety,” he said.

Crews responded properly to the spill, officials said.

The aging tank where the spill occurred held 464,000 gallons of waste when the transfer started in 2004, and about 90 percent has been removed.

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