Chris Schneidmiller
WC Monitor
12/18/2015
The Waste Isolation Pilot Plant in New Mexico might be able to resume nuclear waste storage operations using only one of two new ventilation systems planned to be installed in the underground facility, the Department of Energy said this week.
The facility’s airflow was significantly curtailed following the February 2014 fire and subsequent radiation release that brought a halt to operations, dropping from a standard nonfiltered 425,000 cubic feet per minute to 60,000 CFM in “filtration mode” that became necessary after some segments of the mine were contaminated. The reduced airflow – well below the 260,000 CFM average required under the state permit – limited the amount of personnel and equipment that could conduct recovery operations as DOE and site contractor Nuclear Waste Partnership work to reopen WIPP.
The department has responded with plans to install interim and supplemental ventilation systems that would together increase airflow to 180,000 CFM, according to Don Hancock, nuclear waste safety program director for the nongovernmental Southwest Research and Information Center. The installation process was delayed by months this year when segments of the interim ventilation system (IVS) were damaged during transport and some shipments of ductwork were halted due to poor workmanship by the manufacturer.
They ventilation systems were intended to be operated together, though DOE earlier this year considered starting up the supplemental ventilation system (SVS) ahead of the IVS. The interim system has been placed on its foundation pads and should be connected to the WIPP exhaust ductwork early next year, the Defense Nuclear Facilities Safety Board said in its latest monthly report on the site. That would be followed by testing and anticipated IVS startup in the first quarter of 2016, Hancock said.
Airflow modeling has now found that the existing ventilation and the IVS could provide enough airflow to allow WIPP to begin accepting new shipments of waste, even without the supplemental system, the department said on Tuesday. Transuranic waste has been piling up at other DOE sites for nearly two years, and the department aims to resume WIPP waste emplacement activities by the end of 2016.
Nuclear Waste Partnership also found that the SVS “could be problematic for emergency egress following an underground fire,” the DNFSB said. The problem, Hancock said, is that WIPP needs to have two means of exit from the underground in the event of an emergency; the supplemental ventilation system would use the WIPP salt shaft as an exhaust shaft, requiring the facility to deactivate the shaft hoist and meaning it could not be used as an exit. That leaves only the main shaft. “There’s a basic design flaw with the supplemental system,” Hancock said in a telephone interview.
A DOE spokesperson this week said by email that “A final decision has not been made to decouple the operation of the interim and supplement ventilation systems as part of the Department’s efforts to restart the emplacement of waste at WIPP.”
Nuclear Waste Partnership will seek to validate the airflow models after the IVS begins operations, DOE said. The supplemental ventilation system will ultimately still be needed to support simultaneous mining and waste storage activities, the department added. Under the previous plan for reopening WIPP, the systems together would have cost more than $13 million, not including contingency funding, according to Hancock. The department and Nuclear Waste Partnership are now finalizing a new plan that will update the site’s total recovery cost and schedule. “We are currently reviewing the projected dates and cost estimates for the IVS and SVS,” a spokesperson for the DOE’s Carlsbad Field Office, which oversees the WIPP project, said by email.
DOE ultimately plans to install a new permanent ventilation system that would return the site to its standard airflow levels. However, there is no design, budget, or approval for that system yet, Hancock noted.
