ANS President Dr. Gail H. Marcus's written testimony on nuclear transportation
Submitted to the Senate Committee on Energy and Natural Resources.
Mr. Chairman, as President of the American Nuclear Society, I appreciate the opportunity to provide a written statement on behalf of ANS regarding transportation issues related to the nuclear waste repository at Yucca Mountain for the committee's hearing.
ANS' confidence in the safety of high-level waste (HLW) transportation arises from the robustness of the cask design, the demonstrated safety record of HLW transportation and safeguards in the transportation process. I would like to elaborate on each of these factors.
Robustness of the Cask Design
Casks used for shipping spent nuclear fuel are designed to protect against radiation exposure to the public under both normal and accident conditions. The casks are designed and tested in accordance with requirements established by the Nuclear Regulatory Commission and the Department of Transportation and documented in volumes 10 and 49 of the U.S. Code of Federal Regulations.
The casks are about 15 times thicker than a gasoline tank truck shell and they include three inches of stainless steel with thick lead radiation shields. Typically, for every ton of spent nuclear fuel, there are more than three tons of protective packaging and shielding.
Casks are designed and tested to withstand crashes, fire, water immersion and puncture. To be certified, a cask design must withstand a sequence of four tests that measure its performance in specified crash and fire accident conditions. This means the casks are designed to contain its contents in the event an accident occurs.
Safety Record of Transportation
Over the past 40 years, about 3,000 shipments of spent nuclear fuel have navigated more than 1.7 million miles of U.S. roads and railways. Since the early days of HLW transportation, 90 spent fuel casks have been involved in accidents. None of these accidents resulted in any release of radioactive material.
It should be noted that the impact tests required by Federal Regulation exert forces on the casks that are greater than the impact forces (g forces) in the worst recorded accidents. Temperatures produced in the casks by the regulatory fire tests are higher than those in any recorded fire accident.
In addition, Sandia National Laboratories has conducted three extra-regulatory types of tests:
- A 20-ton truck cask struck by a 120-ton diesel locomotive traveling at 81 mph
- A 22-ton cask on a flatbed crashed into a 690-ton concrete block at 84 mph
- A propane tank car exploding next to a cask in a pool fire, throwing the cask 33 feet.
The casks emerged from these tests with only minor damage, and in none of the tests did the casks fail to hold their contents.
While there would be more shipments of nuclear waste in the coming years as a result of the opening of Yucca Mountain, the probability of radiation exposure to the public from an accident would remain low because casks of the same design would be used and the same safety procedures would be followed.
Recently, concerns have been raised about the potential impacts of terrorist attacks during the transport of HLW. While there are many dimensions to the issue of terrorism that we, as a nation, are only beginning to understand, we can say that the same features that render casks highly resistant to highway and rail accidents tend to make them difficult targets for such attacks. By comparison, many hazardous chemical and other substances are shipped by truck and rail in less robust containers, and are more apt, if successfully attacked, to result in immediate casualties.
Safeguards in the Transportation Process
Public routes used for the transport of nuclear materials must meet strict safety requirements before nuclear fuel is transported. Department of Transportation regulations require carriers of certain controlled radioactive materials, such as spent fuel, to use the safest routes available. Risk assessments of the transportation of radioactive materials evaluate factors such as accident rate, transit time, population density, other vehicles sharing the route and time of day.
The DOT identifies "preferred routes," which consist primarily of interstate highways and bypass routes around cities, where such bypass routes exist, or an alternative route selected by a state routing authority. If the routing authority selects an alternate route, it must demonstrate by a routing analysis that using the alternate route does not increase overall risk. Alternate route selections must be preceded by consultations between DOT and affected state and local authorities before such designations can go into effect.
Most materials being transported are monitored by global satellites and are monitored at all times during the transportation process. Specialized trucking companies handle spent nuclear fuel shipments in the United States. These experienced, specially licensed companies haul all kinds of hazardous materials more than 50 million miles annually. Vehicles are state of the art, equipped with computers that provide an instantaneous update on the truck's location and convey messages between driver and dispatcher through a satellite communications network. Drivers receive extensive training and must be certified by the federal government.
The regulatory requirements on casks and transportation security, and the industry's high level of performance, have produced a safety record that would be difficult to match. This performance record gives us strong confidence that the transport of spent nuclear fuel to Yucca Mountain can and will be conducted without harm to the public.
Mr. Chairman, we sincerely appreciate the opportunities to share our views and facts concerning the safety of transporting nuclear fuel.
The American Nuclear Society is a professional society devoted to advancing nuclear science and technology.