DOE plans to expand WIPP’s capacity and operational life

In an amendment to a 1998 record of decision, the Department of Energy is expanding the available space at its Waste Isolation Pilot Plant deep geological repository for defense-related radioactive waste, and is also now planning to accept waste at the facility for 50 more years than previously planned. The amended decision, which was signed on August 18 by Tim Walsh, assistant secretary for Environmental Management, commits the DOE to a WIPP operating horizon extending to about 2083.

The WIPP site, located near Carlsbad, N.M., is a mined repository that has been excavated 2,100 feet below the surface in a prehistoric salt deposit. In 1998, after analyzing potential environmental impacts, the DOE decided to dispose of as much as 175,600 cubic meters (6.2 million cubic feet) of defense-generated transuranic (TRU) waste at WIPP, treated and packaged to meet environmental standards for the site. Disposal operations at WIPP were slated to continue until 2033.

WIPP is designed to accept TRU waste generated by past, present, and future defense-related operations, including nuclear weapons development and manufacturing; plutonium recovery, stabilization, and management; research and development; environmental restoration, decontamination, and decommissioning; waste management at DOE labs and other government facilities; and testing at other institutions under contract to the DOE.

Additional disposal panels: According to the newly amended ROD, the DOE intends to excavate and use seven additional underground disposal panels (numbered 13-19) for continued disposal of defense-generated TRU waste at WIPP. The excavation and use of these new panels, in addition to panels 11-12, will occur until approximately 2083. (The addition of panels 11 and 12 was approved by the Environmental Protection Agency last year.)

Despite the addition of new disposal panels, the DOE has made no changes to the maximum total volume of TRU waste that can be accepted at WIPP, noting in the amended decision that the "DOE is not revisiting the 1998 ROD to dispose of up to 175,564 m³ of TRU waste generated by defense-related activities."

The new disposal panels are necessary at WIPP, according to the DOE, because some of the original panels have become unusable as a result of deteriorating ground conditions, radiological contamination, and concerns for worker safety. A more detailed explanation is available in the DOE's Supplement Analysis for the Proposed Action to Excavate and Use Additional Disposal Panels at the Waste Isolation Pilot Plant Facility (DOE/EIS-0026-SA-13, rev. 1).

According to the analysis, "Because additional disposal panels at the WIPP facility are required to be able to dispose of TRU waste up to the WIPP LWA [land withdrawal area] total TRU waste volume capacity limit, some TRU waste that was designated for disposal in the WIPP facility would remain at various DOE generator/storage sites . . . if no further action were taken."

143 percent more waste generation: Although the maximum volume of total waste that can be accepted at WIPP under the DOE's amended ROD remains the same, the agency now expects a greater volume of disposable waste to be generated than originally anticipated because of the extended operational life of WIPP.

As explained in the supplement analysis, "Mining, waste handling, and waste disposal operations for Panels 13-19 would not substantively deviate from current facility practices, and . . . TRU waste would continue to meet waste acceptance criteria. The additional 50 operational years of the Proposed Action would result in 143 percent more waste generation than originally analyzed in the 1997 SEIS-II [supplemental environmental impact statement]. However, because annual quantities of waste generated would be the same, those wastes would be managed in the same way, and impacts would be similar as those evaluated in the 1997 SEIS-II."

Infrastructure changes: The DOE stated in its amended ROD that it intends to implement a number of site infrastructure changes associated with the additional planned disposal panels, such as construction of surface structures and facilities to support the new panel development. These structures could include a new salt pile and pond, solar arrays, and upgraded hoisting capabilities (such as shafts, ventilation, and haulage).

Evaluation of potential impacts: The DOE said it evaluated several factors that could be impacted by the new underground panels and surface facility modifications. These factors include visual resources, geology and soils, water resources, air quality, biological resources, cultural and paleontological resources, socioeconomic issues, transportation, and human health.

Broadly, the DOE found that any impacts would be either similar to or less than those presented in the 1997 SEIS-II. In total, 173 acres would be disturbed due to the additional panels and facility modifications at WIPP, but evaluation of geology and soils indicated that new excavation and construction "would not effect notable changes compared to the impacts analyzed in 1997." Other impacts, such as those to air quality, would be temporary. In other instances, the DOE stated that it would develop prevention and protection measures, such as preventing stormwater pollution and mitigating biological or cultural impacts.

Additionally, the DOE calculated that the risk of death due to cancer was about "1,000 times less than the impacts" the agency listed in 1997.

New Mexico wants priority: As DOE-EM prepared its amended ROD for WIPP, it was also engaged in ongoing interactions with WIPP's host state. In February, the New Mexico Environment Department (NMED) issued a large fine against the DOE, claiming that it has failed to prioritize the disposal of legacy nuclear waste from Los Alamos National Laboratory at WIPP. And in April, NMED proposed revisions to WIPP's operating permit to prioritize the disposal of waste generated within New Mexico.