A plan to build two new areas to dispose of nuclear waste began taking shape at the Waste Isolation Pilot Plant after the U.S. Department of Energy published a report on the feasibility of adding an 11th and 12th waste panel to the underground nuclear waste repository.
At WIPP, low-level transuranic (TRU) waste made up of equipment and materials radiated during nuclear activities is permanently emplaced in an underground salt deposit more than 2,000 feet underground.
In its original design, WIPP was planned to have eight panels for such disposal, but much of that space was restricted and abandoned following an accidental radiological release in 2014 that contaminated parts of the underground and led to a three-year pause of WIPP’s emplacement operations.
It was estimated, per DOE records, that 1.8 panels were lost in the incident for a total of 30,861 cubic meters (m3) of lost storage capacity.
The two new panels would be used to replace the space lost in the incident, amid ongoing emplacement in the seventh panel and mining of the eighth panel expected to be complete in 2021.
A DOE-published supplemental analysis (SA) released on April 8 reported the new panels “do not represent a substantial change and will not impact the environment in a significant manner not already evaluated,” read a WIPP news release.
The SA contended a previous environmental impact statement (EIS) from 1997 that analyzed mining the initial panels was adequate for the two new panels and no new impact studies were needed under the National Environmental Policy Act (NEPA).
“There are no new circumstances nor information relevant to environmental concerns or potential environmental impacts that would warrant additional NEPA analysis,” the SA read.
Expansion needed for nuclear waste needs
The new panels were needed, the report read, for continued success of WIPP’s mission to dispose of the nation’s TRU waste generated at DOE sites across the country.
“The DOE needs to safely dispose of the TRU waste that has resulted from atomic energy defense-related activities in a manner that protects the workers, the public health, and the environment,” the report read.
“The two replacement panels address underutilized disposal capacity and protect WIPP workers by avoiding the abandoned portions of the repository.”
The new panels would be added to the western side of the underground, adjacent to a new utility shaft that WIPP is seeking a permit modification to build with a public hearing scheduled in May.
Panel 11 and 12 would be south of the shaft and like the previous panels, they would both be about 300 feet long, 33 feet wide and 13 feet high from floor to ceiling.
“The replacement panels will be mined in the same way as all previous disposal panels at WIPP, and the design of these disposal rooms in the panels will remain unchanged,” read a statement from WIPP.
With the added capacity, WIPP could continue to operate past the initial planned closure date of 2024 to a new closure date of 2033 noted in the SA, peaking at almost 700 shipments per year between 2027 and 2030.
The amount of waste brought to WIPP would not change substantially, the SA read, as the two new panels would replace capacity lost when panels were abandoned and the environmental and public safety impacts evaluated in the past would be unchanged by adding the space.
“WIPP is a key facility in the Department of Energy’s commitment to environmental cleanup of sites that supported production of nuclear weapons, and government-sponsored nuclear research,” WIPP officials said in a statement.
“DOE is committed to operating WIPP in a manner that is safe for employees, the environment and the public, and that allows for the continued support of the cleanup mission.”
New panels part of plan for larger expansion of WIPP?
Adding new panels to WIPP was part of a broader goal, along with adding the new ventilation shaft, to expand WIPP well beyond its historical limit, said Don Hancock at the Southwest Research and Information Center.
Hancock pointed to a November 2020 report from the federal Government Accountability Office (GAO) that discussed plans to add up to nine new disposal panels to WIPP, a move he argued required more public input and environmental analysis despite the SA’s contention such activities were not warranted.
“The SA is additional confirmation that the plan it to expand WIPP,” Hancock said. “The real plan is a whole more than these panels.”
The GAO reported noted the DOE calculated the nine added panels were needed to meet the Department’s TRU waste disposal needs and WIPP’s capacity, following an adjustment in how waste was counted approved in 2018.
This change in counting was meant to reflect the volume of the waste itself, rather than the space taken up by the drums that hold the waste, a shift that meant at the time that WIPP was only a third full while the old method made the facility about half full.
The change was intended to avoid counting air as waste.
“During their planning, DOE officials calculated that nine additional panels, using panel designs similar to those of the existing panels, should be sufficient to meet DOE’s TRU waste disposal needs as outlined in its 2018 Annual TRU Waste Inventory Report,” read the GAO report.
“DOE officials decided that they would construct additional panels up the point at which the volume of TRU waste that could be disposed of in the panels equaled WIPP’s statutory capacity.”
The analysis referenced in the GAO report included an addition 34 metric tons of surplus plutonium that would be downblended before being sent to WIPP by the National Nuclear Security Administration.
That waste was not yet added to the DOE’s TRU waste inventory, the per the GAO report, as the NNSA was amidst of the finalizing documents for its Surplus Plutonium Disposition Program, but the report considered it due to the additional space it could take up.
“According to DOE officials, it was important to consider this waste because it would create a large number of overpacks with smaller pipe containers holding the diluted plutonium,” read the GAO report.
“DOE officials told us that only the volume of the pipes would count against the statutory capacity, so this waste would account for less than 1 percent of WIPP’s statutory capacity but, due to the large number of drums, likely would require significant physical space for disposal.”
Hancock said such a broader effort to expand of WIPP should be brought before the public for discussion rather than “piecemeal” the expansion.
He contended the DOE was hoping to avoid public comments as it could see opposition from groups throughout New Mexico.
“They know if they came out with the whole expansion plan, they would have to have a comprehensive review and public discussion,” he said. “If they do that, they know they’d have some support in the Carlsbad area, but the rest of the state would be strongly opposed.
“WIPP is supposed to be limited. The state did not agree to 12 panels.”
Adrian Hedden can be reached at 575-618-7631, [email protected] or @AdrianHedden on Twitter.