Path mapped to WIPP reopening

01 October 2014

The USA's Waste Isolation Pilot Plant (WIPP) transuranic (TRU) waste disposal facility will resume limited waste disposal operations in early 2016 under a stepwise approach set out in a newly released recovery plan. The facility has been out of action following two incidents earlier this year.

WIPP at sunrise 460 (DoE)
A new day dawns for WIPP (Image: DOE)

WIPP, located 26 miles (42km) from Carlsbad, New Mexico, disposes of military-origin TRU wastes 2150 feet (655m) underground in rooms mined out of an ancient salt formation. The waste itself is a by-product of nuclear weapons research and production, including facility dismantling operations and site cleanup, and typically comprises tools, gloves, clothing and other items contaminated with radioactive elements. TRU waste disposal operations began at WIPP in 1999, but were suspended following the detection of radiological contamination in February, days after an engine fire involving an underground vehicle.

The recovery plan is built around seven key elements: safety; regulatory compliance; decontamination; ventilation; mine stability and underground habitability; workforce retraining and waste stream management. The first phase of the multi-step process, incorporating the necessary actions to enable personnel teams to re-enter the mine and establish an operations base, has already been completed. The second phase of the plan will include steps to mitigate the source of the contamination, restore the necessary conditions to support operations, and incorporate lessons learned from both February incidents into programs and procedures before operations recommence.

Investigations continue

The US Department of Energy, which owns the facility, convened separate accident investigations boards to investigate the two incidents. The board tasked with investigating the underground fire reported its findings in March, concluding that the accident was preventable. The board investigating the later radiological release has issued the first phase of its report, on the response to the radioactive release, in April. The second phase of its investigation focuses on the causes of the release and is still ongoing and expected to be completed by the end of 2014.

A technical assessment team of experts from US national laboratories has also been set up to carry out an independent technical review of mechanical and chemical factors that may have contributed to the radioactive release.

To date, the investigations carried out by the boards indicate that the release originated from a TRU drum that did not meet the facility's acceptance criteria. "This drum was processed at Los Alamos National Laboratory and is known to have nitrate salts, low pH, and organic material, which are likely to have been contributing factors to the release," the recovery plan notes.

Costs and timings

The recovery plan's objective is to resume emplacement of waste in WIPP during the first quarter of 2016. The first wastes to be disposed of on the resumption of operations will be the waste from the recovery actions at the site itself, as well as containers currently stored in WIPP's waste handling facility. Only once those containers have been disposed of will WIPP begin receiving wastes from other sites.

The facility will also require the installation of a new ventilation system before it reaches full operations, and the number of waste shipments that can be processed will increase as the necessary ventilation improvements and equipment are installed.

The costs for the recovery program up until the restart of operations are estimated at $242 million, according to the recovery plan. This does not include the new permanent ventilation, which is estimated to cost a further $65 million to $261 million, and a new exhaust shaft, estimated to cost between $12 million and $48 million.

The recovery plan will be revised as necessary if "substantive new information" is identified during the ongoing accident investigations and technical assessments.

DOE says it is "committed to resuming WIPP operations as a critical part of the environmental cleanup program" and promises to work with regulators, community partners, TRU waste generators and other stakeholders "to ensure that this is done safely and efficiently."

WIPP is operated by Nuclear Waste Partnership LLC.

Researched and written
by World Nuclear News