xt/javascript" src="../static/js/analytics.js"> citizen alert - Yucca Mountain Nuclear Waste Casks - Are They Safe?

Casks of Uncertainty: The NAC LWTS
Citizen Alert Report on Behalf of Western Communities Against Nuclear Transport
July 8, 1998

This month, the first shipment of spent nuclear fuel coming from the foreign research reactors of seven Pacific Rim nations will enter the Concord Naval Weapon Station in Concord California under the US Department of Energy (DOE) Foreign Research Reactor Spent Nuclear Fuels (FRRSNF) Program. This shipments from South Korea will travel on an undedicated ship under the Golden Gate Bridge, through the San Francisco Bay and the Carquinas Straights over the Sierra Nevada mountain range in California by rail on a segment of California railroads that was designated in 1991 by the California Public Utility Commission as the most accident prone rail alignment in California. The North Fork of the Feather River experienced 28 derailments and 72 accidents within 16 years, at the time of the CPUC report in 1991. (Headwaters, Summer 1997, Volume 21, Issue 3)

The propensity for accidents in the Feather River Canyon is greatly increased by effects of one of the biggest El Ninos of the 20th Century. Data from the California Data Exchange Center, which makes available the California Department of Water Resources (CDWR) information, indicates that summary totals of water contributing to the Feather River Drainage may well be over 500% this summer when the snow melts. As early as 4/1/98, the Snow Course Measurement in the Feather River Drainage was 168% above average and a 6/1/98 measurement recorded a staggering 495% above normal. Without a doubt, mudslides will continue to occur this summer. Within the last month, there have been two major mudslides both within a 10 mile area, near Pulga, California, 25 miles from Oroville. One of the mudslides caused a Union Pacific train to derail and three cars containing wine, tequila, furniture and food tumbled into the river.

Union Pacific Railroad Company (UP) is a contributing risk factor as well, as it reels from the disastrous consequences of its merger with Southern Pacific Railroad Company. After a series of nine fatalities to its workers, significant safety problems were identified by the Federal Railroad Administration (FRA). The September 10, 1997 report, issued by FRA found that UP had a "serious breakdown in its ability to implement basic railroad operating procedures and practices essential to safe railroad operations." With unresolved gridlock and other isssues still unresolved by UP, it is questionable whether UP will commit to the additional expenditures necessary to shore up the entire Feather River alignment affected by this year's El NiƱo.

Western Communities Against Nuclear Transportation (WCANT) an alliance of two dozen disarmament, anti-nuclear, and tribal organizations, including: Western States Legal Foundation, Grandmothers For Peace, Chico Peace and Justice, and Concerned Citizens of Plumas County in California, Citizen Alert in Nevada, and Ohngo Gaudadeh Devia and Downwinders in Utah, concerned about the safety of transporting high-level nuclear waste in untested truck casks through the San Francisco Bay and over the Feather River Canyon rail alignment, have identified crucial questions which must be answered by the Department of Energy (DOE) and the appropriate state agencies before any shipments are made.

Executive Summary
"Casks of Uncertainty: The NAC LWTs" is a preliminary assessment to identify the issues and questions raised by the DOE's fraudulent presentation material on the safety of the casks to be used to ship nuclear spent fuel under the Foreign Research Reactor Spent Nuclear Fuels (FRRSNF) Program. These presentation materials: a video about the testing of spent nuclear fuel casks; and subsequent press releases, can be fairly characterized as propaganda,because they serve the purpose of misleading the public into thinking that no accident is possible with the containers DOE plans to use. But the DOE's facts do not stand up to scrutiny.

This report addresses the histsory of nuclear waste container testing in the U.S., it describes how the type of cask to be utilized for the FRRNFS Program, Nuclear Assurance Corporation's Legal Weight Truck cask (NAC LWT) have been tested, and the NAC LWT's actual track record, and poses questions for the DOE and state agencies to answer so that the public can can bear witness to the decisionmaking with regard to the container that will be used to transport spent fuel over the Pacific Ocean, through the San Francisco Bay, and inland over the rails to be stored temporarily at the DOE's Idaho National Engineering and Environmental Laboratory near Idaho Falls, Idaho, while awaiting a permanent disposal site.

Despite the DOE's implications, in a film entitled,"Safe Transport, The Transport of Spent Nuclear Fuel," and in press releases from the Oakland DOE office, that casks to be used for the FRRSNF program have been put through a gamut of full-scale cask tests, they have not. The cask tests which the DOE refers to in the film and press releases were conducted in the late seventies using casks that had been retired for a decade.

The only type of test done on the NAC LWT casks, to be used for the FRRSNF Program, was virtual testing, using computer-simulated models of accident scenarios on casks similar in design to the NAC LWT. These tests, NUREG/CR- 4829, were performed in 1986, by the Nuclear Regulatory Commission (NRC) using contractors at the Lawrence Livermore National Laboratory (LLNL) to test the regulatory standards, not the actual cask.
While it is legal, under NRC regulations, to substitute computer simulated models in place of full-scale testing, the DOE's allusion to full-scale tests in its presentation materials, when in fact the casks have only been computer tested, is a misrepresentation to the public that can justifiably be characterized as "propaganda."

"Casks of Uncertainty: The NAC LWTs," confirms that these spent fuel containers have never been tested at full-scale. It also clarifies and critiques U.S. cask testing in general, and the Sandia tests in particular, describing how edited films of the Sandia and Oakridge National Laboratory tests done in 1977 and 1978 omit crucial cask vulnerabilities revealed by the actual test results.

"Casks of Uncertainty," addresses the actual twenty year track record of the NAC LWT casks, and reveals some of the basic design, manufacturing, and human error flaws to which the NAC LWT casks have been prone.
In light of these uncertainties, the use of NAC LWT casks sets a precedent for choosing casks on the merits of availability, rather than their ability to keep the waste contained during a serious accident. Certainly, the choice of container for the FRRSNF program and the public's reaction to it, willl have a bearing on choices of containers for future shipments of foreign research and U.S. nuclear industry spent fuel.

To summarize, WCANT concludes that DOE must commit to:

  • Full-scale testing of casks

  • Changes in regulatory standards for cask certification to address a wider range of accident scenarios and to account for differences between rail and highway accidents; and

  • Consider using less hazardous shipping routes.

More importantly, in light of the risks related to spent fuel containers, "Casks of Uncertainty" speaks for the need to review an alternative under the "DOE's Nuclear Weapons Nonproliferation Policy Concerning Foreign Research Reactor Spent Nuclear Fuel" not adequately explored in its Environmental Impact Statement - an alternative to store the spent nuclear waste of other nations, on-site under strict international safeguards rather than subject the world's land and oceans to the risks of transporting nuclear waste. For this, the DOE must be able to honestly look at the performance of its casks, and not overlook the NAC LWT's flaws just because there is much spent fuel to ship and very few available containers.

Along with "Casks of Uncertainty" WCANT is submitting to the DOE and appropriate state agencies a list of questions dealing with: 

  • DOE cask testing claims in press releases and video;

  • radiological hazards of spent nuclear fuel, consequences of sever accidents and incidents;

  • and accident liability.

Critique of DOE's Presentation Materials
Beginning in 1997, the DOE made presentations to local governments and tribes on the transportation corridor in four Western states affected by the FRRSNF Program. In these presentations, the DOE presented film footage of full-scale tests of spent fuel casks under a number of accident condition, performed in the U.S and Britain, to imply that the casks to be used in the FRRSNF Program were tested.

The film, Safe Transport: The Transport of Spent Nuclear Fuel," is misleading because the DOE fails to disclose when and where the tests were performed on on which casks. If they had, the public would learn that the casks in the films were not the ones the DOE plans to use for the FRRSNF program, and that the only full-scale tests in the U.S. were done twenty years ago on different casks, ones that had been retired for a decade prior to the twenty-year-old tests. In addition to the fact that the casks in the films were different from the ones to be used for the FRRSNF program, the edited versions of this films from which the video was created, fails to state the startling results of some of the tests to these obsolete casks.

Because the NRC allows small scale and computer simulations cask tests of spent fuel containers to substitute for full-scale tests, the DOE has few full scale test examples to convince the public that spent fuel transport is safe. Rather than telling the truth about the sparseness of their full-scale test data, the presentation materials (i.e., films, slides of the film, and the Feb. 16, 1998 press release) borrow from a full-scale test done in Britain on a completely different cask and from a scale model test without explaining that it is not a full-scale model, to supply confidence about the casks to be used in the FRRSNF program.

The February 16, 1998, press release from Oakland DOE states: "These types of casks have been dropped from a height of 2,000 feet onto a hard desert surface, dropped onto a steel spike, subjected to a head-on collision with a diesel locomotive traveling at 80 miles per hour, crashed into concrete walls at greater than 80 miles per hour, and subjected to a 1,475 Fahrenheit fire for 90 minutes, and tested to a water depth of 660 feet, all without breaching the casks."

What the DOE is referring to with the phrase "these types of casks" the DOE is a very broad classification for all spent fuel containers called Type B casks. Referring to tests done on other Type B containers allows the DOE to gloss over the fact that the NAC LWT has never been full-scale tested.
The search for details about various tests cited in the press release revealed they are a "hodgepodge" of computer models, small-scale tests, and full-scale tests, conducted by the DOE at Sandia and the Oak Ridge National Laboratories, as well as a test done by a public utility company in Britain.

(1) 2000 ft drop tests: refers to full-scale tests conducted by Sandia National Lab (SNL), SAND75-0276, on two obsolete casks, the OD-1 used to ship and store from the Oak Ridge research reactor, and B of E 83 casks used in handling irradiated test capsules. It is surprising that the DOE is using this test for several reasons: one, the casks are so old they do not remotely resemble todays' casks, raising this issue of how tests on obsolete casks could yield anything other than obsolete results: and two, the conclusions of the test did not support that a 2000 ft drop test on a yielding surface would do as much damage as a shorter fall onto an unyielding surface. In the Sandia document, SAND75-0276, Air Drop Tesst of Shielded Radioactive material Containers, the author states, "Comparing these results with the observed results of the 2000 ft drop test leads the author to the conclusion that the 30 ft drop test on an unyielding surface is a more severe environment than the 2000 ft drop onto hard soil." Thus we can conclude that the fall distance is not as important as the density of the surface in which it falls.
(2) Steel spike drop test: At the time of completing "Casks of Uncertainty: The NAC LWTs," efforts to locate a technical report number for the steel spike test had not been fruitful. Since it did not appear to be a test conducted by SNL, it was entirely possible that the DOE was merely quoting the NRC regulatory standard which cask designers and manufacturers must comply with in the cask certification process. It is probable that this test was only computer modeled, due to the high cost of full-scale testing that for-profit cask manufacturers would not want to commit the funds to conduct.
(3) Head-on collision with a diesel locomotive traveling at 80 miles per hour: It was difficult to know if the DOE was referring to a full-scale, small-scale or computer models with this test. When Sandia National Laboratory was questioned, it referenced this item in DOE's press release to a May 1978, "Proceedings of the Fifth International Symposium on Packaging and Transportation of Radioactive Materials, Full-Scale Simulations of Accidents on Spent Nuclear Fuel Systems" in Las Vegas, Nevada. The 80 mph speed of the test indicated that this test may have been done using computer models or small scale because it seemed neither to refer to a test conducted in Britain in which the train which struck a spent fuel container was traveling at 100 mph, or any of the Sandia tests in which speeds of 62 mph were used. This test may be a simulation of a full-scale test done by the British Central Electricity Generating Board (CEGB) in 1984, on a cask made of a single piece of forged steel, very different from the welded steel and lead sandwich models which characterize casks made in America today.
(4) Crashed into concrete walls at greater than 80 miles per hour: DOE said this test was conducted at Sandia, on April 1978(SAND77-1462). Another description of the head-on truck crash tests in Lindsay Audin's October, 1991 paper entitled, "Nuclear Cask Testing Films, Misleading and Misused," the speed of the truck is identified at 62 miles per hour.
(5) A 1,475 degree Fahrenheit fire for 90 minutes: A Sandia scientist said this test corresponded to the same symposium as the third test. But Sandia did a Fire Test Sequence which was more likely the source of this test because the length of fire on the obsolete rail cask that was burned corresponds with the 90 minute fire.
(6) Tested to a water depth of 660 feet: Once again this test was not referenced by the Sandia scientist with a technical report number. It merely referred to the 200 meter water immersion depth required of all spent fuel shipping casks which are a part of the hypothetical accident conditions of transport for Type B packages. The Sandia scientists report that such a test is required by the NRC for certification of any spent fuel package.
Since these tests were performed on different casks, the question remains to be answered about how the NAC LWT were tested. All the DOE had to go on with regard to demonstrating safety of the NAC LWTs were the LLNL computer simulations of accident scenarios using cask models similar to the NAC LWT cask, (See Critique of Modal Study) and the actual twenty year track record of the NAC LWTs, which is not completely untarnished.

In the video presentation, "Safe Transport: The Transport of Spent Nuclear Fuel," the DOE implies that the NAC LWT have been put through all the types of cask tests. "By computer simulation, scale model testing and full-scale prototype testing, the casks are submitted to a variety of destructive scenarios involving catastrophic collisions and stress factors." When in fact, "the NAC LWTs and all of the casks in use today have only undergone computer simulations of accident scenarios," said Marvin Resnikoff of Radioactive Waste Management and Associates, in a May 1998 interview.
Excerpts from the February 16, Oakland press release present the casks as if they have no history. "Spent fuel rods are shipped in containers, or casks, that are designed and independently tested to withstand catastrophic incidents, including derailments." Contrast that with the NAC's actual experience in which a majority were found to have bowed inner liners and had to be removed, several had problems with shielding and valves installed backwards. Contrast it also with a judgement from the NRC when the defect was discovered, "that crash worthiness could not be assured in a cask with this defect." (TNNG, Box 8)

DOE's use of the word, "independently tested" is misleading. One not familiar with with the field of cask design and testing would assume it refers to a process in which each manufactured cask is tested, as opposed to testing only one representative cask of the same design. Additionally, one unfamiliar with the field would not know that the DOE has ways to test without actually testing, ie, small scale and computer model test simulations, or that just computer models of tests are acceptable to the NRC.

Nuclear Regulatory Commission (NRC) Cask Requirements
What the DOE means by "designed and independently tested" in the case of the NAC LWTs, is that a model similar to the design of NAC LWT had been put through computer simulated accident scenarios. The regulatory stresses outlined in Code of Federal Regulations 10CFR71, approximating the most probable worst case scenarios which the NRC requires both train and truck casks to be tested are:

  • A 30 foot drop on a flat, unyielding surface;

  • A 40 inch drop on the end of a 6 inch diameter flat steel stump;

  • A 30 minute engulfing fire at 1475 F;

  • An 8 hour immersion in water 3 feet deep; and

  • An 8 hour immersion (of another container) in water 50 feet deep.

There are many accident scenarios involving a spent fuel cask which the computer model tests and full-scale tests have not studied. Designers and manufacturers of spent fuel casks tend to limit their test to just being able able to meet the 10CFR71 regulations. Even the Sandia crash and burn test films, though spectacular to the unsophistocated eye, covered only a narrow range of accident scenarios, Lindsay Audin critques in Nuclear Cask Testing Films Misleading and Misused, in Oct. 1991. The tests were designed around being able to meet the NRC requirements, not the full range of accident possibilities.

For example, many truck and train accidents involve fires which burn for much longer time than 30 minutes at 1475 F. In "Nuclear Cask Testing Films Misleading and Misused," Audin stated this was due to the fact that rail and truck accidents often involve impacts that create shocks and sometimes fires, aided by vehicle fuel and/or flammable cargoes. One such severe accident in 1982 lasted for two hours with fires which burned 45 minutes over the 30 minute regulatory limit, when a gasoline tanker truck was involved in a collision with a stalled car in the Caldecott Tunnel, near Berkeley, California. Audin report cautions that "this accident involved a single tanker: today's relaxed trucking rules allow double tankers."(Oct.1991)
Rail and highways casks are designed to meet the same standards, even though the rail and truck accident scenarios are quite different. Thus, the DOE can use a truck cask designed for highway transport for spent fuel shipments over the railroad. As in the case of the FRRSNF Program, the DOE will use truck casks to carry spent fuel by boat and rail. Fires which burn for much longer durations than the 30 minute fire at 1475 degrees Fahrenheit are more realistic on the oceans and the railways.

It is unclear how these casks could hold up immersed in water depths of 50 feet or more, since the public has not seen any computer models of immersion tests done at that depth. Many areas of the worlds oceans are deeper than the International Atomic Energy Act requirements for spent fuel containers, (200 meters.) Spent Fuel from the FRRSNF Program will travel through some of these areas. The DOE has conceded that there may be areas on the ocean floor where spent fuel would not be retrievable. The fact that the same requirements apply both to truck and rail casks is problematical. It is not uncommon for a rail fire to burn for 12 hours. Because the NRC regulations apply to both casks used for highway and rail transport, the DOE can use a truck cask designed for highway transport if that is what is available, for spent fuel shipments over the railroad. In the case of the FRRSNF Program, the NAC truck casks will carry spent fuel by boat and rail and have the potential to be involved in a maritime or rail fires which can typically burn for much longer durations.

The Sandia and Oak Ridge National Laboratories Full-Scale Tests
The full-scale tests referred to in DOE presentation materials done in the U.S. were conducted at the Sandia and Oak Ridge National Laboratories in 1977 and 1978 on casks which had been retired for a decade.

Notwithstanding the fact that the tests are antiquated, films of these tests have generated controversy since they were made in the late seventies. Audin's Oct. 1991 critique of these tests describes some of the problems.
"While the tests were performed to assess the applicability of scale and computer modeling techniques to actual accidents, films of them were quickly pressed into service by the DOE and nuclear utilities as "proof" to the public of the safety of the casks."

Additional problems with the tests identified by Audin in the Oct. 1991 report are:

  • The DOE covered only a very narrow range of accident scenarios;

  • The contents and internal conditions of the casks did not reflect reality at the time the films were made;

  • Cask designs had changed, both before and after the films were made, making the tests potentially inapplicable to containers already on the road;

  • The films avoided mentioning cask vulnerabilities revealed during the tests; and finally,

  • The focus of the tests and the films was always on structural integrity, not the subtle leakage pathways more likely to yield a release.

"It is the misuse of these films to represent that the casks are safe that is objectionable... The high speed collision tests represent only two of a larger number of accident scenarios that need to be analyzed to assess the safety of the spent fuel cask transportation."

For example, two of the three casks are only subjected to end-on collisions against a flat surface, in which parts of the truck or cask enclosure absorb much of the impact. The other involved a sideways strike by a train, but no actual collisions occur between the cask and a reinforced body, like a bridge abutment, an accident that where the impacts to the cask would be greater.
"The casks did not contain irradiated fuel which would produce heat and pressure: they held fresh, clean, cold, unirradiated fuel," a serious omission according to Resnikoff and Audin (TNNG) Box 5-9, Sandia National Laboratory's Crash Tests. How valves behave under the higher pressure of irradiated spent fuel is still unknown because the tests were performed under conditions of 26 psi inside the cask, instead of pressures of 130, which may be more normal for hot irradiated fuel.

The fresh fuel which was used for the tests, taken from an assembly from the merchant ship SS Savannah, was clad in stainless steel, a characteristic of the Sandia tests which may have relevance to the FRRSNF Program, since some fuel which the U.S. will be taking back is clad in steel. But again, because the tests were performed on cold, unirradiated fuel rods, the cladding would pose no potential problems, as it would with irradiated spent fuel rods in which the cladding would have become brittle, and possibly cracked, from the heat and pressure of real spent fuel.

Box 5-9 of TNNG, critiques other aspects of the Sandia tests/films. One frame shows a technician checking for radiation before and after the test. But because fresh fuel was used, only one-millionth as radioactive as irradiated fuel, the author noted that there would be little likelihood of detecting much radiation from it, even if the cask had been breached, unless the geiger counter was directly over the crack.

The fact that these films were edited down from a 14 minute to a 4 minute version was and continues to be problematical. The Oct. '91 Audin report said. "The shorter versions eliminated qualifying statements contained in the longer version, and created false impressions."

The editied versions of the film did not include the cask vulnerabilities exposed by the Sandia and Oakridge full-scale tests, the Audin Oct. '91 report said. Omissions by the narrator regarding cask vulnerabilities exposed by the Sandia and Oak Ridge full-scale drop, crash and burn tests include:

  • Effects to the outer shell. The narrator said the fire test showed no damage during the 90 minute period, but fails to mention that the "special steel harness that acted as a shield between the cask and the heat source, can significantly affect the amount of heat input to the cast," a feature which most train casks used today do not utilize. Also unmentioned was the fact that ten minutes after the 90 minute test, "the outer shell cracked open in two places, the shielding began to vaporize, and the test was stopped as a result," or that the cracking was due to faulty manufacture and welding.

  • Effects to pressure relief values: During the fire test, the buildup of pressure inside this cask caused its pressure relief valve to open, venting steam to the environment. In addition, "Both the opening of this valve, and the potential for steam or water to be contaminated with fuel crud or particles, remained unmentioned," Audin critiqued. "Such events could have had serious health consequences, especially to emergency personnel near the cask."

  • A Leak: The film soundtrack which states that no radiation would have been released from the 90 minute fire test, but two of the tests actually resulted in leakage of water from the cask. TNNG Box 5-9, states that in one case "100 cc, about a half a cup, was released. Had the cladding been damaged, the fluid would have been seriously contaminated (as happened in a 1980 shipment), the internal pressure would have been higher, and the pathway that allowed the 100 cc release would probably have released a much greater volume of fluid in the form of steam."

In the films of two drop tests done consecutively on an obsolete model of cask at the Oak Ridge National Laboratory in 1978, the narrator fails to mention how the second drop without a impact limiter caused a crack to form along a weld leading directly to the cask's inner cavity, creating a pathway for leakage, a situation which is applicable to an accident scenario in which a multiple drop occurs, the first of which knocks off the impact limiter.

Another glaring omission is the fact that the casks which the DOE used for the Sandia tests were designed to different standards than casks today. These casks were built in the sixties before the Atomic Energy Commission changed the standards. Under the old standard, casks were designed to withstand stressses, including a one-hour high temperature fire, instead of today's 30 minute requirement.

Today's casks are designed to use impact limiters, which are a kind of shock absorber on each end of the cask. The casks used in the Sandia film were designed to remain intact without these impact limiters. In addition to being tested with impact limiters, the casks in the film utilized radiative cooling fins, not present in the NAC LWTs, and the tie downs used in the crash tests were of a superior design, much stronger than chain connections typically used today, and held the cask in a position that maximized absorption of the impact by the truck, instead of the cask. (Oct. 1991 Audin)

Lindsay Audin wraps up the Oct. 91 study with the conclusion: "By such critical omissions, the Sandia presentations withhold and distort information showing that the consequences of transportation accidents could be significantly more severe than claimed by the DOE and the nuclear industry." Audin characterized such productions as "propaganda" and said "that are clearly out of place in an honest debate over nuclear transportation safety."

Omissions in DOE's Presentation Materials Regarding British Tests
Similar omissions occur with respect to the film footage of Britain's test used in DOE video of a train hitting a spent fuel container at 100 mph. Once again, the tests were performed on different casks than the ones to be used for the FRRSNF program. However, the DOE does not state this. These casks differ significantly from those used in the U.S. and even Britain's older model casks, in that the bodies were forged out of one piece of steel, rather than several welded sections. And like the Sandia tests, the casks contained cold, unirradiated fuel.

As in the U.S., the purpose for the tests done by the British Central Electricity Generating Board, (CEGB) in 1984, was to confirm computer code performance and materials evaluation, on a new design of cask, but also to affect more acceptance by the public for spent fuel shipments, by demonstrating the steps which a new package went through to gain approval. During this time, it was felt that the public perception of transport safety and the nuclear option in the UK was loosing ground," David Snedeker said in his Dec. 1990 report, entitled "Nuclear Waste Transportation Package Testing: A Review of Selected Programs in the United States and Abroad."

Public acceptance was important as a considerable amount of nuclear shipments go on continuously, 500 per year, between the two dominant utility companies in the UK and the Sellafield Reprocessing facility. There, like in the US, public concerns about the shipments could not be quelled by mere models of a very narrow scope of accidents.

Prior to this crash test, two drop tests, in full public view, had caused the CEGB to redesign its spent fuel containers. The first drop test on the edge of the Magnox cask had caused the lid to unseat. During the test, for a second the lid unseated and a spray of water was released (within regulatory limit) before the lid's seal reseated itself. Because the public was allowed to watch the test and see the release, it saw the potential for contamination. To CEGB's favor, they took the information received from the tests, and used it to eliminate lid movement aspects of the Magnox and the family of casks to which it is similar, even though the "leakage" was considered minor, a decision was made to improve the design further to eliminate the lid movement that occurred during the drop and crash test.

The CEGB found it hard to convince the public of the safety of the casks through the regulatory drop sequence tests. "The 30 ft drop onto an unyielding object, which looked like ordinary steel faced concrete had no real meaning," Snedeker wrote in his report. So they decided with the upgrades to the cask lid in place, they would go for a more true-to-life accident scenario: to hit the Magnox cask with a 140 metric ton locomotive and three railroad cars going 100 miles an hour.

The casks made it through the crash and fire caused by residual diesel fuel unscathed. Pressure tests recorded the same internal pressure as before the tests, thus, CEGB determined the payload would not have suffered and the casks were assumed to be safe. Even though the British cask test went well, the DOE's use of the film did not address the flaws. According to David Snedeker's 1990 report, the demonstration, while successful from CEGB's viewpoint, did not impart as much energy to the cask as the regulatory test sequence. Calculations after the impact sequence revealed that the 100 mph, 140 metric ton train only imparted about 1/3 the energy to the cask as the cask had seen during the thirty foot drop."

To summarize, it should be noted how the UK's response to public perception and cask results differs from that of the US. While it appears that Britain used their tests results to improve design, we see no evidence of that in the US. Instead, the U.S. downplays the results by editing them out, to not have to change designs. A glimpse of why this may be can be found in the Snedeker report. "An obvious question about such a test program has to be the effect of a national utility and government policy in developing such a program," acknowledges Snedeker. "It is clear that a for profit company could ill afford the cost of the CEGB program."

The NAC LWT Casks
Even though the NAC LWTs were never tested using full-scale prototypes, what is known about them from over twenty years of commercial use gives us reason to be concerned. A whole section in TNNG, Box 5-8, The NAC 1 Cask - A Troubled Record, describes problems with Nuclear Assurance Corporation and their NAC -1: including flaws in design or manufacturing of the NAC 1, violations by NAC with regard to delays in reporting problems to the NRC, and instances of contamination caused by human error.

The first discovery of a problem involved both a design/manufactured flaw and a problem with how Nuclear Assurance Corporation responded. On March 28, 1979, technicians at Duke Power Company in South Carolina discovered that the internal shell of a NAC-1 cask was bowed out of shape. They called NAC to report the problem, but NAC "made no effort to locate the other casks of the same type or to stop any impending shipments. " (TNNG -83)
At the time, NAC-1s were being loaded to ship spent fuel from Dairyland Power Cooperative reactor at La Crosse, Wisconsin, to fuel storage pools at Morris, Illinois. Nine days went by and eight more shipments between Wisconsin and Illinois were made before NAC notified anyone of the bowing problem. When the casks used to ship spent fuel between Wisconsin and Illinois were finally inspected, one was found to have a bowed inner liner. During that time, the NRC issued a suspension order to inspect all the NAC-1s, and two others, built by other manufacturers, were found to have bowed liners, making a combined total of four casks out of six to have bowing problems. (TNNG -83)

"The source of the bowing problem remains officially undetermined," TNNG said. "It is reasonable to conclude however, that there is a generic fault with either the design or the manufacturing process as it is unlikely that two different companies separated by thousands of miles and several years could make exactly the same mistake." And the NRC issued a finding, "that crash worthiness could not be assured in a cask with such a defect."

In addition to the bowing problem, several NAC casks were found to have a problem with uneven shielding, another design or manufacturing process defect. When the first bowing problem was discovered at the Duke Power plant on the NAC-D model, another discovery was made by technicians that Nuclear Assurance Corporation had welded a copper plate onto the outside of the outer shell to increase shielding. Not only were these weldings done without permission by the NRC, the NAC should have known that an accident with a high temperature fire would have alloyed the copper to the steel and seriously weaken it. Because NAC did not report these welds to increase the shielding, years of shipments had taken place with these flawed containers. The author states, "It is unfortunate that such realizations came after more than five years' use of faulty casks, involving over 300,000 miles of shipments. (NAC 1979c)(Under Box 5-8 of TNNG).

TNNG describes another example of external shielding being added to the NAC-1s by NAC. The newest model, the NAC-E, arrived at the San Onofre reactor in California emitting 11 to 40 times the legal limit of radiation at several points on the cask surface. "Unbeknownst to the San Onofre technicians, this cask had been used four months previous to ship a leaking fuel assembly from the Oyster Creek, New Jersey, plant to a research facility near Columbus, Ohio."(TNNG Box 5-8). "The cask had become so severely contaminated in the process that external lead shielding had to be added. (NRC, 1981d)

TNNG reports several mysterious episodes with the NACs:
One involved an inexplicable movement of a radioactive "hot spot" from one end of the cask to the other after it had been decontaminated several times.
Another involved a February 1981 incident with the NAC- D cask found to have surface contamination after shipping it empty to the Oyster Creek plant. The cask had not been used for five months since it had been withdrawn because of the inner liner bowing problem.

The same NAC-1D cask that was thought to have been bowed was one year later put back into use because it was found not to be bowed, was involved in some contamination resultant of cask "weeping." Weeping is a situation in which spent fuel from wet storage contaminates the cask surface even after it has been washed and inspected. According to Audin's 1988 report entitled "A Review of Human Reliability Issues In The Transportation Of Spent Nuclear Fuel," weeping is generally more harmful to cask handlers than to the public. But a case of it combined with human error, resulted in contamination of a major interstate in Pennsylvania.

During a routine swipe test of the NAC 1D, at the Oyster Creek plant on February 1981 an inordinately high contamination level (100 times greater than the regulatory limit ) was discovered on the surface of the NAC 1D. When it was discovered, the decision was made to decontaminate the cask and apply a layer of heavy paint designed to hold contamination in place for the next phase of the cask's journey, to the Batelle Laboratories in Ohio, and an NRC inspector on duty at the time observed the process. However, according to Resnikoff(TNNG, Box 5-8), "the wrong type of paint was used." The paint began dissolving off the cask during a rain storm in Pennsylvania. When the drivers noticed the peeling paint, they continued on perhaps unaware that surface contamination was probably being spread on the highway. NAC notified the NRC five days later, but no action was taken and the amount of radiation released was never determined.

To sum up the track record of the NACs, a majority of them had to be retired because of inner liner bowing, and both the NAC-D and NAC-E, two containers in use today, held fuel which contaminated the containers and external shielding had to be used. Thus, it is reasonable for citizens to be concerned about their use to ship FRRSNF. It is also plausible to suggest that the DOE chose them not on the merits of their safety record, but rather because there are very few casks available for commercial shipments.

Critique of the NRC's Modal Study (NUREG/CR-4829)
Thus far, this report has shed some light on DOE's claim to having conducted a variety of tests on casks like the NAC, including computer simulation, scale model, and full-scale prototype testing in its presentation materials. Not only do we find little evidence of full-scale or small scale tests of the NAC, there is little evidence to suggest that the casks in question were adequately modeled in computer simulations.

In 1986, the NRC commissioned the Lawrence Livermore National Laboratory (LLNL) to complete some new tests on spent fuel containers to test the standards responding to criticism that the standards are only theoretical because of the lack of full-scale tests to confirm them. LLNL used a cask similar to NAC truck cask for the Modal Study, NUREG/CR-4829, "Shipping Container Response to Severe Highway and Railway Accident Conditions."
According to "Nuclear Waste Shipping Container Response To Severe Accident Conditions: A Brief Critique of the Modal Study," (Audin, Dec.,1990) "the purpose of the Modal Study was to examine the validity of existing cask design and certification standards, via engineering analyses of the responses of a representative cask to transportation accidents." But the concern that the standards are too theoretical to ensure the safety of individual cask designs, speaks to the need for full-scale prototype testing, rather than more engineering analyses or computer models.

Thus, flaws exist in the premise of the Modal Study. However, these are not the only flaws to be identified. Audin's critique calls into question the integrity of the study(Dec. 1990). In his executive summary he writes, "while an improvement over many prior efforts in this area, (such as NUREG -0170), it unfortunately fails to create a realistic simulation either of a shipping cask, the severe conditions to which it could be subjected, or the potential damage to the spent fuel cargo during an accident."

It is misleading for the DOE to rest its case on the safety of the NAC's for the FRRSNF Program on the Modal Study, since the DOE only used design similarities to the NAC LWT in the Modal Study. Audin states, "Since no experimental work was to be performed, a simplified cask design was created to be used as input to various computer simulations of impact and fire"(1990). Thus, only aspects of the NAC, a lead-lined cask with steel inner and outer shells, surrounded by a water neutron shield, was used in the preliminary analysis, and in the secondary analysis, a more detailed version of the cask, using materials and dimensions nearly identical to the NAC-1 container, was used. But it is important to note that the experiments were not done on real NACs.

Audin's 1990 study finds three basic problems with the Modal Study cask analysis:

  • Its portrayal is seriously outdated by changes in cask design and payload;

  • It does not reflect details of construction that create areas and points of vulnerability; and;

  • It fails to account for human errors in cask fabrication, loading and maintenance that could easily compromise cask integrity.

In addition, Audin states that "The reader should note how a deficiency in one area creates conditions not examined in other areas. There are major synergistic effects inherent in the problems, and the Modal Study failed to model them, thereby greatly oversimplifying may aspects of its accident simulations.

Critique of the Accident Scenarios of the Modal Study
"In some ways, paralleling the present regulatory scheme made the Modal Study's goal of verifying it almost a self-fulfilling prophecy," Audin stated." The 10CFR71 tests were designed as highly simplified simulations, not of actual accidents, but of the worst conditions that could prevail in almost any accident, which LLNL translated into its own parameters of strain and temperature in order to categorize an accident's potential for causing a radiological release."

"It is important that the reader avoid also 'signing on' to the 10CFR71 perspective while thought is given to the accident conditions that could realistically prevail," Audin goes on to say, "the degree to which LLNL does so causes the Modal Study to lose some of its credibility."

While LLNL examined a number of accident scenarios, using the 10CFR71 performance tests as a starting point, "it discounted the need to examine criticality after a collision and the immersion in water (the final 10CFR test), because its probability calculations indicated that such a scenario would occur only once in ten million years" (Audin). 

Two other critiques of the Modal Study by Audin include (December 1990):

  • Its failure to realistically simulate some characteristics of drops, collisions, fires and other possible scenarios not given sufficient examination;

  • and LLNL failure to sufficiently intersect the effect of one accident condition with those that follow.

View or Casks' Parts
After Computer Simulated Models of Accidents

Neutron Shield
LLNL modeled a cask with an empty water neutron shield but failed to account for the increase of heat transfer (70%) from the loss of the insulating effect of water. Audin's critique argues that since the time to melt lead is roughly proportional to this rate, it is possible that lead in a truck cask could melt in 20 minutes rather than 1.08 hours as calculated by LLNL.

LLNL also overestimates the neutron shields ability to retain its shape when the cask is struck by an object or if the cask strikes a flat surface, in that it does not discuss a puncture and the loss of the dead air space which would allow entry of hot gases into the empty shield. Even if only a portion of the insulating space is lost when the shield collapses, that would cause very uneven heating and expansion of the lead, not necessarily near the volume allowed for such expansion.

Similar impact by a train sill or other hard object could rip away part of the outer layer of the neutron shield, once again creating a pathway for increased and uneven heat transfer. In general, LLNL found lead to yield slight warpage of the inner and outer shells but not enough to create major strain. But Audin looks at the synergistic effect of the lead melt to weaknesses in welds and penetrations which could be affected by this local lead expansion.

Outer Cask Shell
LLNL's model focussed almost exclusively on strain as the way in which casks could be damaged from impact. According to Audin, "The possibility of puncture of the outer shell was, in effect, ignored by LLNL's analysis." They modeled various regulatory stresses outlined in 10CFR71, such as a drop of the theoretical cask on a flat unyielding surface, followed by a second drop onto a steel stump, in order to examine the strain that would result from such theoretical encounters and attempted to find "real" structures that would yield equivalent strain. In the Modal Study, LLNL found that impact with soft soil would require an impact speed in excess of 150 mph, and hard soil and rock required lower speeds, as did some concrete structures. Audin concedes that while "this approach is acceptable from the standpoint of screening out some types of accidents, it only looks at total energy transfer." Two other factors that weigh strongly in an accident are the most vulnerable angle and point of impact, which are more difficult to determine, (Audin).

A sidewise impact with a bridge abutment or similar unyielding structure was given scant analysis, due to LLNL conclusion that such a collision is "remote." In LLNL's response to criticism from the Los Alamos National Laboratory peer review of the Modal Study, LLNL stated that "this type of impact would be similar to that calculated for an impact with a train sill, or the front of a locomotive. (L.E. Fischer, LLNL, 1/16/87)

Audin's statement is that this opinion is not acceptable (Dec. 1990). "A train sill impact involves contact over a very small area with an object having limited kinetic energy". A bridge abutment is essentially an unyielding column. Impact would yield a great deal of lead movement and bending stresses, as the cask would continue to move while the center of the cask rapidly slowed down.

As if the Modal Study was a test in a vacuum, it fails to utilize information gained from full-scale testing eight years prior with regard to the vulnerability of cask welds to impacts. LLNL's analysis of the outer cask shell assumes that, at all points on its surface, it maintains its ability to yield to strain without breaking but the study failed to acknowledge that real casks have numerous welds that may be weaker than pure steel. (Audin 1990)
Audin's 1990 report criticizes the scope of the impact analysis. Because the strain from a drop onto a steel stump could not be duplicated (in LLNL's opinion) by a real situation, two puncture scenarios were examined: a high speed perpendicular sidewise impact by the end of an I- beam, and collision with a train sill. LLNL's conclusion is that the shell and shielding would be severely dented but not penetrated. Thus aspects of puncture remained unexamined. For example there was no analysis of lead shielding loss due to a puncture, followed by a fire.

To conclude the critique of the Modal Study, Audin states that "While the basic simulation of striking a flat surface may be acceptable, the puncture study is not." The I-beam test failed to adequately model a fall of the cask onto train tracks, in that the I-beam in the test height equaled the cask diameter. In real life, impact would involve contact with the top side of a much smaller I- beam, not its end, and over a considerably different surface area, changing the dynamics of the study.

Lead Shielding
A cask's lead shield is important to keep gamma radiation from pouring out of the cask at a lethal rate. Loss of the gamma shielding would seriously hamper any efforts by emergency personnel. The 1990 Audin critique cautions the reader that even a partial loss of the gamma shielding could be disastrous. Most first responders would not know to conduct a 360 degree radiological survey around a truck or train fire prior to approaching it, unless they knew the hazards of failing to do so when spent fuel is involved. It is unlikely that many of the responders on the FRRSNF corridor have the equipment to do a radiological check. Furthermore, it may not be protocol for most emergency response teams to do a circumferential check since it is not even suggested in the Department of Transportation's "Emergency Response Guidebook." (1984)

Failure to fully investigate puncture and cracking of the outer shell creates the rationale for avoiding consideration of the loss of shielding, a very serious potential problem.(Audin 1990) The only mechanism for major lead movement covered by the Modal Study is slumping due to an endwise impact of the cask onto a hard surface. Since opening of the outer shell may be a realistic possibility, examination of slumping effect alone in insufficient analysis upon which to base the rest of the study.

Two other problems in the lead shielding were identified in the Audin critique of the Modal Study not accounted for by LLNL as a result of impact: lead's heat capacity and how it alloys with nickel in the steel at a certain temperature. As was discussed earlier, the loss of the neutron shield greatly accelerates heat transfer and the likelihood of rapidly reaching very high temperatures at the inner surface of the outer shell. But the Audin critique states that "Even if the exterior steel layer of the neutron shield was still intact , LLNL apparently did not examine the temperature at the point of surface contact between the lead and the steel outer shell and thus did not consider the potential for alloying at that point." Lead will alloy with the nickel in steel outer shell and sufficiently weaken it, causing it to become embrittled and cracks to form which could lead to lead loss. Because only a very thin layer of lead needs to reach 1050 F for this phenomenon to occur, LLNL should have more thoroughly examined when that point would be reached in order to properly assess its likelihood.

According to Audin, the heat capacity of lead creates another condition not covered in the Modal Study. All fire simulations in the study examined the temperatures of the lead mid-points during the fire. Since the temperature of the spent fuel will always be lower at this time due to the buffering effect of the lead, a short fire that doesn't yield a mid-point temperature of 650 F during its duration is not considered to cause fuel rod bursting or oxidation. Examination of the temperature after the fire is out could be crucial, however, to assessing the fuel rod condition since a DOE sponsored study by Pacific Northwest Laboratories (PNL-2588) examined the fuel temperature during and after a fire and found the highest point was reached hours after the fire was out, due to the delayed heat transfer into the inner shell and the insulating effect of the lead.

In the PNL study, very high temperatures resulted, sufficient to burst the rods. In Audin's final comments, he states that LLNL should have examined short fires that cause lead mid-point temperatures of less than 650 degrees to assess their delayed temperature at the spent fuel. If short fires eventually yield high internal temperatures, the likelihood for a significant release is heightened, since short fires are much more common than long duration fires (at least according to the distribution used by LLNL).

Inner Shell
The inner shell is the cavity which holds the fuel basket containing spent fuel in place. It must remain rigid and straight when compressed (as in an endwise impact of the cask against a surface). The Modal Study impact simulations assume the inner shell remains rigid and straight, and thus does not provide any bending stress on the fuel rods during an endwise impact. According to the 1990 Audin analysis, any previous bending of the cask would exaggerate effects to the inner shell.

The author notes that the actual cask simulated by LLNL, the NAC-1 cask, suffered from a bowing of the inner shell. He also clarifies that 4 out of 7 were taken out of service due to this problem, and that it was not noticed until several hundred shipments had been made. Audin also speculates that had such a container been involved in a severe endwise impact, the bowing could have created a vulnerability to bending or buckling of the shell, which could damage the fuel rods, and lead to leakage in the shell. Damaged fuel rods coupled with puncture or lead melt could have serious consequences, yet this scenario was not explored in the Modal Study, yet another example of the disconnect between what is known about the actual casks from real experience and the models in the Modal Study.

Penetration Subsystems
Audin's study criticized the fact that the Modal Study assumed that valves, welds, and other subsystems were protected by design features, when in fact actual NAC-1 history should have made penetration subsystem an issue in the Modal Study. Several NAC-1 containers were found to have a chronic problem with valve closure. "After several instances of casks arriving with valves open to the inner shell, it was found that the valves were installed backwards, due to confusing instructions," Audin reports. "Vibration of the vehicle while in motion apparently opened them." It overly focussed on the subsystems's ability to limit the escape of any spent fuel material to that which can migrate or be driven out through the small diameter, tortuous passageways presented by the damaged penetration systems." Audin states that "while it may be true that chunks of spent fuel would be blocked by narrow cracks or by bends in the tubing, it is not chunks that are the problem." It is the vapors, gases, and fine particles which can escape through tiny cracks and fissures which pose a greater risk, since inhalation of radio nuclides in spent fuel poses the greatest radiological hazard.

Welds were also found to be overlooked in the Modal Study, even though Audin states that those involved in the installing the tubing also create vulnerabilities, as evidenced in the Oak Ridge drop tests and in earlier prototypes of British casks. In these tests without impact limiters, he states, "a cask suffered cracks in its welding along its drain lines that extended from the inner shell our to the surface of the containers." While the steel around the welds stood up, the welds did not.

Impact limiters
The Modal Study failed to model an accident scenario without impact limiters. It assumed a perfect cask and limiters and a truck cab were both present to absorb much of the cask deceleration on impact, even though an impact at an angle could tear off the limiter, leaving the cask end vulnerable to a second impact, Audin said. Even though present regulations do not consider multiple collisions, Audin said, "They are not unusual in train derailments."

Cask seal
Audin states that the cask seal possesses a particular vulnerability not evidenced by the other materials that make up the cask. Audin's critique of the Modal Study states that LLNL, "may have been conservative when it assumed that seal failure would occur if strain exceeded 0.2%, but there is no experimental data cited to support this number; and a lower number may be possible." Failure to address delayed thermal transfer could be significant, Audin stated, in that the simulations appear only to cover the period while the fire is in progress (and while the neutron shield provides insulation) to arrive at a figure that the temperature at the seal would not reach the point of breakdown (500 F.)

Audin's Final Comments of Modal Study
"LLNL made several simplifying assumptions that, unless closely examined, could be the sources of unseen problems," Audin said. He points out when simulating the type of steel used in the cask, LLNL used a different variety. He also points out that in one of the drop simulations, a sidewise impact of a rail cask on a flat surface. LLNL assumes the welds to remain intact, when in fact the sheer weight of the lead shielding has nearly flattened the container. LLNL's use of the full-scale tests to verify or benchmark simulations of accidents must be called into question Audin critiqued, as evidenced by failure to discuss how the outer shell during a fire test cracked and failure to cite how the casks in the British tests were a solid forged design, not the welded steel and lead sandwich simulated in the Modal Study.

Conclusion: Lingering Uncertainties
Surrounding the NAC LWT Cask

Given the lack of full-scale tests for the NAC LWTs and the NAC LWTs track record, it is difficult to have confidence in the NAC LWT's for upcoming spent fuel shipments. Additional full-scale testing is necessary to study unresolved factors still from the Modal Study:

  • Accident impacts to the cask without the buffering effect of the harness or flatcar;

  • Impacts which puncture the neutron shield causing the loss of its insulating effect, and the resultant lead melt, and possible loss of the gamma radiation shielding;

  • Delayed thermal transfer and its effect upon lead melt time and upon seals;

  • How valves hold up in casks containing spent fuel under accident scenarios where the pressures involved with hot, irradiated fuel is almost five times higher than cold, irradiated fuel; and

  • Built-in weaknesses of welds displayed in drop tests.

In the Modal Study, the DOE parallels the NRC regulatory standards too closely and loses sight of the actual historical performance of the casks it is modeling. For example, the LLNL did not model accident scenarios to understand how bowing of inner shell, a flaw which the NAC LWT was prone, might be affected by an impact. The Modal Study takes place in a vacuum, Audin suggests, with all of the models running with the assumption that the inner and outer shells will not bend, even though there is blatant evidence to suggest they do bend under non-accident scenarios.

The need for more studies to determine the safety of cask welds is needed, since cracks in welds occurred in both the Sandia and British drop tests. In addition, the Modal Study made no differentiation between the welding material and unworked steel. In general, all of the components of the Penetration Subsystems (valves, welds and tubing) were assumed to be protected by design features.

DOE has not dealt with many important factors which could potentially jeopardize the safe transport of nuclear waste. Some factors include:

  • The myriad of uncertainties associated with human error;

  • The condition, content, weeping and radiological output of the fuel assemblies the US will be receiving from other nations;

  • How a truck cask might hold up under accident scenarios never modeled, such as a mudslide condition, in which a train car holding a spent fuel container may be buried under tons of dirt and rock, a cask being immersed at the bottom of the ocean, or an accident involving a maritime fire which can burn for hours.

WCANT calls upon the DOE and appropriate state agencies to respond to the list of questions submitted below in connection with the Preliminary Assessment: "Casks of Uncertainty; The NAC LWTs" - before any shipment is made on either rail alignment over the Sierra. For this, the DOE must be able to honestly look at the performance of its casks, and not overlook the NAC LWT's flaws just because there is much spent fuel to ship and very few available containers.

Because the casks in question have not been tested at full-scale, and the full-scale tests on the obsolete casks represented by the DOE may or may not have any relevance to modern type B casks, it is important that DOE commit to the full-scale testing of these containers. While planning for the full-scale tests, the DOE should at minimum explain to the public areas in which the NAC LWT casks are similar to or different to the ones shown in the films, and answer questions as to why the NAC LWT were chosen to ship the spent fuel from overseas.

Because of the risks related to spent fuel containers, the concerns in this report speak for the need to review an alternative under the U.S. DOE's Off- Site Fuels Policy, not adequately explored in its Environmental Impact Statement for the project. The alternative to store the spent nuclear waste of other nations on-site under strict international safeguards was given scant attention because it was deemed too costly. However, in order to foster public understanding for why the U.S.must take back the spent fuel of 41 nation, the DOE must make the case -- on a country to country basis -- that it is more dangerious to leave the spent fuel where it is than to bring it here.

The burden of proof is on the DOE to demonstrate how it is less dangerous and expensive to ship high-level radioactive waste half way around the globe in untested containers, jeopardizing the earth's land and water to the possiblility of a spill, in order to store it at a temporary site in the U.S. The federal government has a duty to its citizenry to thoroughly balance the risks of nuclear proliferation against the risks of a nuclear accident caused by the transportation of spent fuel within our communities.

Questions Which Need to Be Answered


  1. Has any NAC LWT cask been tested full-scale to demonstrate compliance with the NRC cask performance standards?

  2. Has any NAC LWT cask been tested full-scale to determine the consequences of a terrorist attack employing high-energy explosive devices?

  3. What scale-model tests and analyses were performed during the NRC certification process to demonstrate that the NAC LWT cask meets the NRC cask performance standards?

  4. How do the SANDIA crash and fire tests cited by DOE specifically demonstrate NAC LWT compliance with the NRC cask performance standards?

  5. How do the SANDIA 2,000 foot air drop tests cited by DOE specifically demonstrate NAC LWT compliance with the NRC cask performance standards?

  6. Does DOE support legislation currently proposed in California to require full-scale testing of spent fuel shipping containers?

  7. Would DOE support federal legislation to require full-scale testing of spent fuel shipping containers?


  1. In general terms, how do the radiological characteristics of TRIGA SNF from foreign research reactors being shipped to Idaho National Engineering and Environmental Laboratory, compare with the characteristics of Pressurized Water Reactor (PWR) SNF, the predominant type of U.S. commercial power reactor SNF which could be shipped to the proposed repository site at Yucca Mountain?

  2. How do the radiological characteristics of a NAC LWT cask loaded with TRIGA SNF (about 110 assemblies) compare with the characteristics of a NAC LWT loaded with PWR SNF (one assembly):
    (a) total activity or source term (curies)
    (b) major radionuclides present, type of radiation emitted(alpha, beta, gamma), and primary human health concerns (affected organs) for each radionuclide
    (c) radionuclde inventory by curies and percentage of total curies
    (d) surface dose rate (rem per hour) and duration of unshielded exposure at one meter resulting in lethal dose (500 rem)


  1. What are the details of the maximum severe transportation accident scenario considered in DOE's EIS for the FRR SNF shipments? 

  2. What was the nature and extent of the radioactive release?

  3. What was the estimated cleanup and disposal cost?

  4. What are the details of the maximum severe transportation terrorism incident considered in DOE's EIS for the FRR SNF shipments?

  5. What was the nature and extent of the radioactive release?

  6. What was the estimated cleanup and disposal cost?

  7. Have there been any rail accidents in the U.S. in the past two decades which created crash and/or fire conditions in excess of the hypothetical accident conditions assumed in the NRC cask performance standards?

  8. How would a NAC LWT cask inside an ISO shipping container be affected by a rail accident which included an 8-hour, engulfing fire at 1475 degrees Fahrenheit?

  9. How would a NAC LWT cask inside an ISO shipping container be affected by a successful terrorist attack employing current generation antitank weapons such as TOW or Milan missiles?

  10. How would a NAC LWT cask inside an ISO shipping container be affected by a rail accident which included significant crush forces, for example from massive boulders (125 tons or larger)?


  1. In general terms, how would the Price Anderson Act liability system apply to FRR SNF shipments?

  2. Will the Price Anderson Act limitation on government contractor liability ($500 million) apply to FRR SNF shipments?

  3. Will the Price Anderson Act nuclear utility shared liability provisions apply to FRR SNF shipments?

  4. In the event of an FRR SNF transportation accident which causes significant economic damages but does not involve any release of radioactive materials, who is responsible for:
    (a) costs associated which precautionary evacuation
    (b) loss of business income
    (c) loss of property value due to stigma effect or perception of risk
    (d) loss of individual income and/or medical expenses due to psychological trauma

Audin Lindsay, Nuclear Cask Testing Films, Misleading and Misused, October l991.

Audin, Lindsay, Nuclear Waste Shipping Container Response to Severe Accident Conditions: A Brief Critique of the Modal Study, December 1990.

Audin, Lindsay, A review of Human Reliability Issues in the Transportation of Spent Nuclear Fuel, 1988.

California Public Utilities Commission, Headwaters Summer 1997, Volume 21, Issue 3

Code of Federal Regulations, 10CFR71.

Department of Energy, Proceedings of the Fifth International Symposium on Packaging and Transportation of Radioactive Materials, Full-Scale Simulations of Accidents on Spent Nuclear Fuel Systems, Las Vegas, Nevada.

Department of Energy, Safe, Transport, The Transport of Spent Nuclear Fuel video.

Department of Transportation, Emergency Response Guidebook, 1984,

Lawerence Livermore National Laboratory (commissioned by Nuclear Regulatory Commission), Container Response to Severe Highway and Railway Accident Conditions, NUREG/CR-4829, 1986.

Pacific Northwest Laboratories (DOE sponsored study), PNL-2588.

Resnikoff, Marvin and Lindsay Audin, The Next Nuclear Gamble

Sandia National Laboratory, Air Drop Test of Shielded Radioactive Material Containers, SAND75-0276.

Snedeker, David, Nuclear Waste Transportation Package Testing: A Review of Selected Programs in the United States and Abroad, 1990.

Contact Citizen Alert for more information.

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