The Department of Energy should consider further limiting construction at Hanford’s vitrification plant until it has aggressive strategies to address risk developed and in place, the Government Accountability Office said in a report released Thursday.
It also recommended that DOE take a broader look to make sure it has found the best alternatives to address technical and schedule problems at the plant under construction.
The report was prepared at the request of the Senate Armed Services Committee after DOE proposed building a Low Activity Waste Pretreatment System and a Tank Waste Characterization and Staging Facility to address schedule and technical issues at the plant.
DOE has estimated the two facilities to be built outside the plant could add as much as $1 billion to costs to clean up Hanford, but the GAO indicated the costs for those facilities and other changes at the vit plant could be higher.
Construction on the vitrification plant began in 2002 with building being done just ahead of completion of ongoing design of the plant to get it operating sooner. It is a strategy that DOE no longer uses for such large, complex projects.
The plant is intended to turn up to 56 million gallons of radioactive waste into a stable glass form for disposal. The waste, now held in aging underground tanks, is left from the past production of plutonium for the nation’s nuclear weapons program.
Because of unresolved technical issues, including the possibility of an unplanned nuclear reaction, construction stopped on the plant’s Pretreatment Facility and part of its High Level Waste Facility in 2013.
The Pretreatment Facility has been planned to be the first stop for the waste at the plant, separating it into a low activity radioactive waste stream and a high level waste stream for separate treatment and disposal.
To allow more time for the Pretreatment Facility to begin operating, DOE has proposed building the Low Activity Waste Pretreatment System outside the vitrification plant. It could separate out some of the low activity waste to send it directly to the Low Activity Waste Facility for glassification.
The second proposed facility, the Tank Waste Characterization and Staging Facility, would characterize, blend and prepare waste for treatment before it is sent to the vitrification plant.
It would reduce the size of some radioactive waste particles to allow them to be processed at the Pretreatment and High Level Waste facilities and possibly allow some waste to bypass the Pretreatment Facility and be sent directly to the High Level Waste Facility.
The Low Activity Waste Facility also has technical issues, the GAO report said.
A design review last year by a panel of outside experts identified 536 vulnerabilities, including 110 that could result in “severe consequences” to the ability to operate the plant. The review looked at just half of the facility’s systems.
Among possible problems are weaknesses in the plant’s ventilation system that could allow radioactive gases to escape. DOE does not know the potential level of exposure to workers if a leak occurs, the GAO said.
The cost to address the issues could be $525 million. However, the final review and steps to address issues have not been completed.
A May 2014 review of half of the technical systems in the High Level Waste Facility found all 12 reviewed were at risk of failure and required a changed design or more engineering studies. Among the risks is a release of hazardous or radioactive gases.
While DOE has employed an aggressive risk mitigation strategy for the vit plant’s Pretreatment Facility, it has not done the same to address all technical uncertainties at the High Level and Low Activity waste facilities, the GAO report said.
“By continuing construction activities without employing aggressive risk mitigation strategies, DOE has limited assurance that technical challenges will be solved or mitigated without significant rework,” the GAO report said. Rework could be extensive and expensive at the two facilities, it said.
It recommended that all systems at the two facilities undergo a design review and that DOE consider expanding the partial halt of construction at the High Level Waste Facility and halting construction at the Low Activity Waste Facility.
To date, $19 billion has been spent in the past 25 years on projects at the Hanford tank farms and on several different waste treatment strategies, without treating any waste, the report said.
The GAO is concerned now that DOE is focused too narrowly on the two proposed facilities to solve some technical issues and make up for delays, including those caused by pauses in construction at the plant.
It believes DOE excluded consideration of other alternatives to address tank waste treatment and the danger caused by the potential leakage of radioactive waste from aging tanks by narrowly defining what it needed to address.
“These two projects might represent the best path forward, but without unbiased statements of mission need, DOE is unable to explore other alternatives, including some that might be less costly solutions,” the report said.
One possibility could be building more underground tanks to safely contain waste while more time is taken to resolve technical issues at the vitrification plant.
DOE also should revise cost and schedule estimates of the two proposed facilities to meet industry best practices, the GAO report said. Now its estimates cannot be considered reliable, it said.
The Low Activity Waste Pretreatment System cost estimate does not include costs for handling secondary waste, costs to modify tank farm infrastructure, costs of additional infrastructure and costs for permits. The additional work could add $150 million to costs, which does not include addressing some possible risks that may need to be addressed, the report said.
The Tank Waste Characterization and Staging Facility rough cost estimate also does not include all costs, including installing a system to get waste to the facility and then to the vitrification plant.
DOE officials in Washington, D.C., have estimated that just the Tank Waste Characterization and Staging Facility could cost from $1 billion to $1.5 billion, the report said.
DOE generally agreed with recommendations in the report, but it still issued a lengthy response out of concern with some of the conclusions in the report.
Of most concern is that DOE look at other alternatives to building the two proposed new facilities, said Mark Whitney, DOE acting assistant secretary for environmental management, in a response to the GAO.
The new facilities would allow a phased approach to treatment, allowing some waste to be treated before technical issues are resolved elsewhere at the plant. Some waste could be treated by the end of 2022, Whitney said.
It is the best approach to meet DOE’s legal obligations for tank waste cleanup, he said.
The GAO report does not recognize that DOE cannot unilaterally abandon or reject the legal obligations governing tank waste cleanup, he said. DOE and the state of Washington have each submitted competing proposals in federal court to modify court-enforced deadlines related to tank waste.
DOE is continuing to work on cost estimates as plans advance for the proposed new facilities. Additional costs were not included because they will be part of the operating budget for the tank farms, Whitney said.
As for the proposal to stop construction, Whitney said construction is only continuing on parts of the High Level Waste Facility not affected by technical issues or their possible solutions.
Construction is nearly completed on the Low Activity Waste Facility, and remaining risks are being addressed, he said.
DOE agreed with another GAO recommendation, that it bring in an outside agency to help review and evaluate the vitrification plant design and the approach to resolving technical challenges at the plant.
Bringing in outside agencies and review teams is a strategy DOE has used previously at the vit plant. Whitney said DOE would consider alternatives to enhance oversight and then quickly implement the best alternative.