Part 3 of 3 Parts (Please read Part 2 first)
     In 2021, China began construction of an underground laboratory in Gansu province that scientists will utilize to study whether the site is suitable for the geological disposal of spent nuclear fuel. The laboratory will be located eighteen hundred feet underground below the Gobi Desert in granite bedrock. If the site is found to be acceptable after testing, the complex could be built in the 2040s and begin operating around 2050.
     Russia is also considering the construction of an underground research laboratory for similar purposes at a site that it has deemed suitable for geological disposal near the Siberian city of Krasnoyarsk, in the middle of the country.
     Considering the time and cost required for construction and the extreme complexity of geological disposal, some countries are pursuing medium-term solutions known as consolidated interim storage.
      These big interim waste storage facilities are being designed to operate for many decades until geological disposal becomes more widely available. Such sites will also consolidate storage to alleviate the risks associated with high-level waste being spread across multiple sites. Interim sites would have advanced capabilities and technologies that will allow for safely storing canisters of spent nuclear fuel. They would also be sited in areas considered to be at a much lower risk than the reactors sites where the spent nuclear fuel is usually stored. The new facilities would be away from coastlines and in geologically inactive, remote locations.
     The U.S. is home to a huge volume of spent nuclear fuel. It amounted to eighty-six thousand tons as of last year. Most of it is currently in storage at nuclear power plants. Two private interim storage projects for spent nuclear fuel are being considered in the U.S. They are Holtec’s HI-STORE facility in New Mexico and Interim Storage Partners’ project in Texas. However, the continuing lack of progress in the U.S. on a final disposal solution could preclude social acceptance of interim sites.
     Matt Bowen works at the Columbia University Center on Global Energy Policy. He said, “States will likely be more hesitant to accept a consolidated interim facility on their land, worrying that ‘interim’ will become long term if there is no final disposal site.”
     A critical emerging issue is the higher levels of radioactive materials in contemporary fuels and whether they pose a greater risk than legacy fuel.
     The average amount of thermal energy generated per unit of nuclear fuel has increased from the early days of nuclear reactor operation. This results in a higher “burnup” of spent nuclear fuel. Higher burnup reduces fuel costs for the industry. However, it results in waste that is more radioactive and releases more heat as it decays than lower burnup fuels. This was reported in a July 2021 report to U.S. Congress by the US Nuclear Waste Technical Review Board.
     The panel’s report said, “Extensive research on low burnup fuel has provided confidence that it can be stored for extended periods and transported.” The panel stressed that this is not the case with high burnup fuels.
     Changes to the chemical and physical characteristics of the nuclear fuel and its fuel rod assemblies at higher burnup levels are not well understood, according to the report. These different characteristics might increase corrosion and embrittlement of the cladding on the storage canisters, increase pressure buildup inside the canister, and create other changes that could be particularly concerning during storage, transportation, and disposal.
      Another outstanding question is the potential risks posed by the possible need for repackaging spent nuclear fuel that has sat in canisters for decades for transportation or insertion into a geological disposal site.
      The momentum towards a new era of nuclear power is predicated in part on government and nuclear industry claims that new technological solutions to the permanent disposal of spent nuclear fuel will be here soon. However, big challenges remain in their realization at the necessary scale. It is impossible to minimize the real and persistent challenges of existing and future spent nuclear fuel management. This will ultimately shape the outlook moving forward.