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Nuclear Waste: Yucca Mountain Shipments Similar to Today’s, Experts Say By Mike Nartker While no formal transport system has yet been established, Yucca Mountain transports are expected to be similar to nuclear waste shipments conducted at present, sources told Global Security Newswire last week. “Spent fuel is the most protected of hazardous materials and will continue to be so in the future,” said Eileen Supko a nuclear engineer with Energy Resources International. The U.S Energy Department, though, has just begun planning for the repository’s opening, currently scheduled for 2010, and the transportation details have not yet been “nailed down,” she said. Yucca Mountain is expected to be the storage site for 70,000 metric tons of nuclear waste, which would arrive at the site in about 56,000 truckloads. This works out to about six trucks per day over the next 30 years, according to an article in the January/February 2002 issue of Technology Review (see GSN, Jan. 17) Nuclear power plant operators are eager to begin shipping nuclear waste to Yucca Mountain when the repository is operational, said Mitch Singer, media relations director of the Nuclear Energy Institute, an industry organization. The waste is currently kept on site at nuclear power plants in spent fuel pools, which was never meant to be a permanent solution, he added. Singer estimated that waste shipments would begin within months of the repository’s opening. About 75 to 80 percent of the waste shipments to Yucca Mountain would travel via rail, Supko said. A train could carry about five times more heavy shipping casks — which weigh close to 120 tons when fully loaded — than a trailer truck. Engineers first prepare spent fuel for transport by placing it in stainless steel baskets within a shipping container, which is the current method for shipping safe fuel, according to a report from NEI. Two steel cylinders surround each basket, forming a cavity into which lead is poured to block radiation. A thick outer layer of shielding material around the container further blocks the release of radiation, and the layers of containers are sealed with steel lids. A train transporting nuclear waste is required to have a buffer car placed between spent fuel cars and other cars. Rail waste shipments to Yucca Mountain will likely be sent via a dedicated train, Singer said. All nuclear waste shipments must first have their security plans approved by the U.S. Nuclear Regulatory Commission, Supko said. The shipping routes are inspected ahead of time and “safe havens” are set up along the route. The shipments are also tracked through Global Positioning Satellite systems and escorted, Supko said. They get armed escorts when they pass through urban areas. She added that the armed guards are only provided through major population centers because of the higher population density and greater level of risk in the event of an incident. A contracted spent fuel transporter will notify the governors of the states along a route seven days in advance of any shipments and will let them know precisely when the shipment enters and leaves each state, Supko said. The public will also be given some notification, though it will be limited due to security concerns. Shipping Containers are Main Safety Measure Shipping containers themselves are the primary security measure for nuclear waste transports, Supko said. She cited the extensive testing the canisters undergo to demonstrate their ability to withstand a transportation accident or a terrorist attack. The canisters are put through several tests to evaluate their durability, according to the NEI report. For example, containers were loaded onto a truck and crashed into a 700-ton concrete wall at speeds up to 80 miles per hour. Another test involved dropping containers 30 feet onto a steel-reinforced concrete slab, which is comparable to hitting a concrete slab at 120 miles per hour. Containers were also totally submersed in water and in a pool of aviation fuel burning at over 2,000 degrees for 90 minutes. In all tests, the canisters did not rupture nor was there damage to the spent fuel inside, according to the NEI report. “Although dented and charred, the containers remained totally intact to protect the used fuel they would carry,” the report said. Shipping Containers’ “Achilles’ Heel” Other experts disagree, however, that the nuclear energy industry’s reliance on the durability of the containers is sufficient. Nuclear waste shipping regulations have not been upgraded since the 1960s, said Edwin Lyman, scientific director of the Nuclear Control Institute, a nonproliferation organization. He added that any new regulations would have to be designed to cover a wide range of tests. Container safety requirements are not strict enough, and real-life examples have often exceeded testing situations, Lyman said. For instance, fossil fuels often burn at higher temperatures than those used to test the containers, Lyman said. That could be a factor if a train or truck carrying spent fuel shipping containers were involved in an accident with a petroleum tanker, he said. A potential design flaw in the containers is the rubber seal used under the steel lid, Lyman said. The seal is the cask’s “Achilles heel,” he said. The rubber seal eventually fails if exposed to temperatures between 300-350 degrees Fahrenheit for about an hour, according to Lyman. If the seal would fail, radiation from residue on the outside of the spent fuel, known as “crud,” could vent into the air. If the temperature of the spent fuel itself increases to 700 degrees Fahrenheit, a self-sustaining fire could break out inside the shipping container. That fire could then lead to fuel rod failure, which could release large amounts of radiation. Although a steel seal would be more resilient, Lyman said, the nuclear power industry chose to use the rubber seals for cost reasons. “That’s the way it was done and they weren’t forced to do [anything differently],” he said. Little That States Can Do Already some state and local officials have begun to voice opposition to waste shipments coming through their areas en route to Yucca Mountain. Las Vegas Mayor Oscar Goodman recently said he would arrest anyone who attempts to transport nuclear waste through Las Vegas. State and local officials, however, have little legal recourse to block a shipment routed through their areas, Supko said. Federal interstate commerce laws prevent states from arbitrarily enacting legislation to block commerce. Instead, states will be encouraged to work with the Energy Department during the routing process, Supko said. Waste shipment routes preferred by the Energy Department already circumvent major cities and population areas, she said. States can place some restrictions on transports, such as limiting the hours or weather conditions the shipments can travel, and can recommend alternate routes. Since most of the shipments will be delivered by rail, which has set routes, it would be nearly impossible for a state to use these restrictions and alternate routes to completely block a shipment, Supko said. Public interest in waste shipments will be high when a permanent waste storage site is first approved, and it is up to the nuclear industry and the Energy Department to provide accurate information to reassure residents along a waste shipment route, Supko said. She added, however, that over time the shipments will become a mundane, everyday occurrence and the public will lose interest. “It’s like when you see a gas tanker on the road next to you,” Supko said. “You don’t think anything about it.”
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