An assessment of tritium supply alternatives in support of the US nuclear weapons stockpile

Nuclear weapons require the periodic replacement of tritium, a radioactive gas that decays at approximately 5.5 percent per year. Currently no tritium-supply facility exists in the US, and due to the decay, the tritium inventory will fall below the required reserve level in 2011. To decide how to fill this projected gap, the US Department of Energy assessed 10 tritium-supply alternatives, including several types of new reactors, an accelerator, and the use of commercial reactors. The DOE compared the alternatives with respect to three objectives: production assurance, cost, and environmental impacts. We combined a dynamic production-simulation model and probabilistic assessments of schedule, production capacity, and availability risks to predict the production behavior of each alternative over 40 years. We also assessed the cost and environmental risks. The secretary of energy decided to pursue both the commercial-reactor and accelerator alternatives, based, in part, on the results of this analysis.