The price tag for cleaning up nuclear waste at Hanford site just went up another $4.5 billion

The U.S. Energy Department said Friday that its long-troubled attempt to build a plant to process highly radioactive sludge at a former nuclear weapons site in central Washington state will cost an additional $4.5 billion, raising the project’s price tag to $16.8 billion.

The Hanford treatment plant, a small industrial city with some two dozen facilities on a desert plateau along the Columbia River, is more than a decade behind schedule and will cost nearly four times the original estimate made in 2000.

The government aims to transform 56 million gallons of deadly sludge stored in leaky underground tanks into solid glass, which theoretically could then be stored safely for thousands of years.

But the effort has involved an extended history of errors, miscalculations and wrongdoing. The result has been a massive, partially built concrete facility that has been under a stop-work order for three years because of serious technical doubts.

The biggest technical problems involve two giant facilities, a melter building for high-level radioactive waste and a pretreatment building to prepare the sludge for chemical processing.

After an exhaustive technical review, the Energy Department at the beginning of this year ordered fixes for more than 500 problems, some of them fundamental design deficiencies at the melter. Construction of the building and equipment was 78% complete at the time of the review.

And in November, the Justice Department settled a False Claims Act suit against two major contractors at the plant, San Francisco-based Bechtel Corp. and AECOM, an engineering, design and construction management company based in Los Angeles. The allegations originally were brought by three engineers at the plant, who had long raised concerns that the fundamental design of the plant was flawed. The two companies agreed to pay $125 million in damages, a portion of which will be awarded to the three whistle-blowers.

The Justice Department in its suit alleged that the companies improperly billed the government for materials and services from vendors that did not meet quality control requirements, for piping and waste vessels that did not meet quality standards and for testing from vendors that did not have “compliant quality programs.”

The giant cost increase that was disclosed Friday came under a contract modification that the Department of Energy said would deliver the “best value” for the government and taxpayers.

“DOE is committed to addressing the environmental legacy of decades of nuclear weapons’ production activities at the Hanford Site in a safe and cost-effective manner,” said Kevin Smith, manager of the office that oversees the waste treatment plant construction. “We are confident that the modified contract and baseline represents the most effective and expeditious path towards beginning tank waste treatment at Hanford as soon as practicable.”

But outside watchdogs say the giant cost increase could jeopardize the cleanup at a time when the incoming president, Donald Trump, has already sharply criticized high-cost government projects and contracts.

Tom Carpenter, executive director of the Hanford Challenge, which has helped whistle-blowers disclose problems at the site, said the new cost estimate puts a target on the plant that could lead the Energy Department to begin searching for lower-cost and less safe solutions to the waste problem.

One potential lower-cost remedy at Hanford, which has been used at other former nuclear waste sites, would be to pour concrete into the tanks to solidify the waste and then simply leave it in place. The risk is that the concrete might eventually break down, leak radioactivity into the groundwater and contaminate the Columbia River about seven miles away, Carpenter said.

“There are a lot of question marks about the fate of this facility,” Carpenter said.

The revised plan disclosed Friday is part of an effort to get the waste treatment plant started up sooner, though the estimated delay for full operational status seems to be growing.

In 2013, then-Energy Secretary Steven Chu stopped most construction on the project after a whistle-blower warned about a potential for explosion from accumulated hydrogen gas in the melter tanks. In an effort to get the cleanup moving again, Chu’s successor, Ernest J. Moniz, ordered that some of the lower-level waste be solidified without any pretreatment — a so-called direct feed system — and on a faster schedule at the low-level melter.

The early processing could begin in 10 years or less, but the full capability for the most highly radioactive sludge that requires the high-level melter is now scheduled for a 2036 start-up, some 20 years past the original schedule, Carpenter said.

“It is an astounding date,” he said.

ralph.vartabedian@latimes.com

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