Menace or Miracle? Rethinking Nuclear Waste
Managing radioactive waste in the United States has been a contentious issue for decades, and it likely hinders the expansion of nuclear power. Because of the extremely high energy density of uranium, the total amount of waste is relatively small, but some of it requires very careful handling and storage. Development of the Yucca Mountain repository for spent nuclear fuel was halted by the Obama administration in 2010, but a new bill introduced by Rep. Mike Conaway in September may be gaining momentum as an alternative. The Interim Consolidated Storage Act of 2015 (H.R.3643) would pave the way for private facilities that could manage and store high-level waste and spent nuclear fuel. Several companies have expressed interest in operating such facilities in far west Texas and eastern New Mexico. We will discuss the laws, economics, environmental challenges, and regulatory processes behind storage facilities for spent nuclear fuel and high-level waste.
But what if spent nuclear fuel isn’t really spent, just partly used? All commercial nuclear power plants in the United States currently use enriched uranium as fuel. In this type of fuel supply chain (commonly called an open fuel cycle), less than 2% of the original uranium actually fissions to create power. The remainder from the enrichment process is called depleted uranium, while the discharged reactor fuel is called spent nuclear fuel. This spent nuclear fuel is almost exclusively stored at reactor sites today. Whether the United States will pursue long-term storage of spent nuclear fuel that is retrievable remains to be seen. In other countries such as France and Japan, spent nuclear fuel is reprocessed into new fuel. Although it is currently cheaper to mine new uranium for nuclear fuel in the United States, there are compelling arguments for pursuing closed fuel cycles with uranium reprocessing and recycling. Some of these schemes could extend the uranium supply for thousands of years, even taking into account exponential growth, and reduce the amount and danger of spent nuclear fuel. We will discuss advanced fast reactor designs and fuel cycles to turn spent nuclear fuel into power and reduce the quantity and hazard of the resulting waste. Other topics for discussion may include the Department of Energy’s deep borehole disposal strategy, the merits of retrievable storage, and the economics of mining uranium and thorium compared with reprocessing spent fuel.