Radioactive Waste 213 - Holtec Speeds Up Decommissioning
Dealing with spent nuclear fuel is a serious problem from nuclear power plant operators across the world. Spent nuclear fuel is filling up the cooling pools at nuclear power station around the U.S. When a reactor reaches the end of its life and needs to be decommissioned, disposing of the spent fuel is a major task. The U.S. government identified Yucca Mountain as the site for a spent fuel repository in 1987 and the U.S. promised to have the repository operating by 1999. However, the funding for the project did not come through until 2002. IN 2009, the project was canceled over environmental and political concerns. The soonest that the U.S. will have a national repository for spent nuclear fuel is now estimated to be 2050.
Without a national spent fuel repository, the choices have been to shut down a plant and leave the spent fuel in the pool for several decades before removal, shut down the plant and move the fuel to onsite temporary storage in dry casks after a seven year cooling period or shut down the plant and move the spent fuel to an offsite temporary dry cask storage facility after the seven-year cooling period.
Holtec is a major manufacturer of dry casks for temporary spent fuel storage. They have developed a proprietary neutron absorbing material called Metamic-HT. Metamic-HT is an aluminum boron carbide metal matrix composite. It is used to construct spent fuel baskets for their new line of dry casks. The spent fuel baskets made of Metamic-HT are friction welded which produces superior welds to other techniques. Metamic-HT spent fuel baskets have ten times the thermal conductivity of conventional stainless steel fuel baskets. This permits the spent fuel to be moved from cooling pools after only a two and a half year cooling period as opposed to that current seven-year cooling period that is required before spent fuel is removed from the cooling pool.
Holtec has just announced that they have developed what they are calling a "proto-prompt" decommissioning process which they claim could be used to decommission a closed nuclear power plant in about five years. This much faster than current decommissioning practices. The new Matamic-HT material is one of the developments that makes the new decommissioning process possible. Holtec said that industry concern over the possibility of loss of water causing zirconium fires in cooling pools at closed nuclear power reactors was one of the motivations for developing the new process to speed up decommissioning.
Entergy announced last fall that it was going to decommission the Vermont Yankee nuclear power plant several decades sooner than original estimates. Holtec dry cask technology will be used to speed up the timetable. Holtec has announced that it will submit all necessary documents to the Nuclear Regulatory Commission to secure a permit for an interim storage facility for spent nuclear fuel in New Mexico on land that is being acquired by their partner, ELEA LLC. The HIGH-STORAGE Consolidated Interim Storage Facility will be able to accept spent nuclear fuel retrieved from retired nuclear power reactors.
