Each truckload of waste in urban areas such as Las Vegas and Reno is required by law to have a car with armed guards aboard at the front and the back of the rigs, de la Garza said. That will keep the escorted waste shipments moving and the traveling public at bay. A serious transportation accident could damage the shielding around the cask, possibly releasing its radioactive contents. A terrorist attack using high-energy explosives could crack open the cask, dispersing radiation. The casks under design are expected to emit 10 millirem per hour, equal to the radiation from one chest X-ray, when they are intact.
Radiation exposure drops quickly with distance.
At about 3 feet, radiation doses should be at background levels. In gridlock, however, a person sitting in a car next to a cask containing nuclear waste could get a radiation dose equal to that of four chest X-rays if the traffic jam lasted long enough. The DOE hasn't finalized the transportation mode or routes. It's preferable to do it by rail. The DOE prefers to build a rail line from a remote transfer station, such as Caliente, northeast of Las Vegas, then transfer the nuclear casks to heavy-haul rigs, de la Garza said.