By Van Smith
Published in City Paper, March 26, 2003
For three days in July 2001, chemical tankers and railroad cars filled with paper burned out of control in a downtown tunnel under Howard Street. As the inferno’s smoke cleared, the National Transportation Safety Board (NTSB) started its work to determine the fire’s origin–an ongoing, secretive investigation whose long-awaited preliminary results, at last word, are expected to be released sometime this spring.
Unbeknownst to most, though, in September 2001 the Nuclear Regulatory Commission (NRC) also began studying the Baltimore fire and obtained privileged information from the NTSB investigation. The NRC hoped to lay to rest a controversial question: Would a nuclear-waste rail cask, a heavy-duty container designed to move spent nuclear fuel around the country, have leaked any of its deadly contents had it been in the hottest part of the Baltimore tunnel fire? In February, the NRC’s results were released: The agency predicted that a cask would have survived intact. But not everyone is convinced by the study’s findings.
“The NRC’s report is an attempt to downplay the real-world conditions that might actually cause casks to fail and release radioactive materials, as we believe the Baltimore rail-tunnel fire would have done,” Robert Halstead told City Paper after the report was released. Halstead is a consultant for the state of Nevada’s Agency for Nuclear Projects, which has battled the NRC for years over nuclear-waste transportation issues.
Halstead was one of dozens of nuclear-waste safety experts, nuclear industry officials, engineers, and citizens gathered at a March 6 public meeting at the NRC headquarters in Rockville to debate the protocol the NRC will use to determine transportation-cask safety and durability. The Baltimore tunnel fire was very much on the agenda.
Views on the risks posed to nuclear-waste transportation casks by an event like the Baltimore fire have been divided since news of the fire spread across the country in the summer of 2001 (“Hot Line,” Sept. 12, 2001). At the time, President George W. Bush had yet to sign off on a plan–which he did approve last year–to ship the nation’s 70,000 tons of spent nuclear fuel to a central repository at Yucca Mountain, Nev. Opponents–primarily anti-nuclear activists and the state of Nevada–saw in the tunnel fire a real-life episode that could be used to fight the Yucca plan.
Critics pointed out that the Howard Street tunnel was initially on the NRC’s proposed waste route from Constellation Energy’s Calvert Cliffs Nuclear Power Plant in Southern Maryland–where a growing inventory of more than 930 metric tons of spent fuel is stored– to Yucca Mountain. They said that if the tunnel fire had burned hot enough and long enough to damage a cask carrying spent fuel, there would be reasonable grounds for concern that potentially deadly radioactive material might be released. Though scale-model tests and computers have been used to gauge the casks’ strength, critics argued, the casks have never been tested on a full-scale basis. So who can say for sure that a real cask could have survived this very real fire?
Yucca proponents, primarily the nuclear industry and its regulators, dismissed such notions as fear-mongering. They stressed the strength of the casks, asserting that the computer models and scale testing provide enough assurance that a 130-ton rail cask will meet the regulatory standards. They also touted the industry’s long record of safety in nuclear-waste transportation: about 3,000 spent-fuel shipments over nearly 40 years, and only eight accidents, none involving a release of radioactivity.
Right around the time the NRC started to gather data about the Baltimore fire, the Sept. 11 terrorist attacks occurred, ushering in a new era of heightened security around the nation’s nuclear-power complex. A video of a 1998 Aberdeen Proving Ground test was obtained by City Paper in February 2002, showing the impact a portable missile warhead would have on a rail cask–it would blow a hole right through the cask wall to possibly catastrophic effect (“Hot Load,” Feb. 20, 2002).
Subsequent concern over the safety of nuclear waste shipments have led to some changes. The Howard Street tunnel has been removed from NRC’s maps of proposed routes for nuclear waste bound for Yucca Mountain; new maps show that Calvert Cliffs’ shipments may instead move by barge up the Chesapeake Bay to the Port of Baltimore. And more significantly for nuclear-waste safety advocates nationwide, the NRC now plans to conduct full-scale transportation-cask testing. As a result, the March 6 NRC hearing was devoted to debate over how to conduct testing, including much heated discussion of the Baltimore tunnel fire.
“St. Patrick’s Day will mark 25 years since the first time that I got involved with the full-scale cask testing issue,” Halstead said by way of introducing himself to attendees. “And in all that time I can’t ever remember the NRC holding a meeting solely for the purpose of discussing full-scale testing. So this is a special occasion.”
Halstead handed out a paper he’d presented a week earlier at a conference in Tucson, Ariz., that recommended comprehensive full-scale cask tests in light of the Baltimore fire’s intensity. “Analyses of that accident by Nevada consultants and by the NRC both conclude that fire temperatures in the Baltimore rail tunnel reached or exceeded 1,500 degrees F,” the paper points out, “although estimates of the fire duration at this temperature vary from seven hours to more than 24 hours.” The regulatory test a cask must pass for certification, meanwhile, is 1,475 degrees Fahrenheit for a half an hour. The difference between the estimated conditions in the Baltimore fire and those in the regulatory standard is so great that Halstead proposes a cask simply be destroyed by fire to see how much heat one can take for how long before it breaks.
Halstead cited a study released in September 2001, conducted for the state of Nevada by Radioactive Waste Management Associates of New York, that predicted that a cask would have failed in the Baltimore fire, causing a release of radioactive cesium gas and the contamination of downtown Baltimore.
As for the NRC’s study, which was a computer simulation conducted by the federal National Institutes of Standards Technology (NIST) based on privileged NTSB information about the fire and data from a staged tunnel fire in West Virginia a few years ago, Halstead said, “We dispute the assumptions and the findings.
“Nevada consultants were barred from attending NRC meetings regarding that report, which sure as hell undermined our confidence in the proceeding,” he said of the February report (which was actually completed last August). He went on to say that the only way to gain “confidence in this report is for the NRC to bring the authors” from NIST in for “a very detailed technical review.” A few heads nodded at Halstead’s suggestion, but otherwise his call to haul in the NIST team for questioning went unheeded.
“The Baltimore fire ought to be the standard that we look at to see if the thermal test reflects what can happen in the real world,” Halstead said. “Unfortunately, instead of having a technically objective and unbiased [NRC] report that captures to the best of our ability what happened in that tunnel, we now have a report that we believe is seriously deficient both technically and in terms of public confidence.”
Kevin Kamps, head of the Nuclear Information Research Service, a non-profit organization that also opposes the Yucca project, picked up on Halstead’s criticism when his turn at the microphone arrived. “I was amazed,” he said of the NRC report, “that the impact of the fire on the radiation shield in the container was beyond the scope of the analysis.” The radiation shield is an inner layer of material, which usually includes lead, that surrounds the packages of spent fuel cells and is a key protective element in a cask.
But Chris Bajwa, the author of the NRC report on the Baltimore fire and an engineer with the NRC’s Spent Fuel Project Office, explained that his study “assumed that after the fire the [radiation] shield was gone, and the dose rates they calculated [from the resulting release] were within the regulatory limits.” Thus, he said, the study shows that “the consequences of a spent-fuel cask being involved in a fire such as the one that occurred in the Howard Street tunnel are minimal. Our conclusion is that there would be no radioactive release.”
At this, Halstead dug in his heels. “It’s clear we’ve got a situation here where two different parties evaluated this fire using different sets of assumptions, and both stand by their findings,” Halstead said in his closing remarks. “As is so often the case in these kinds of disputes, the question is in the assumptions.”
One reasonable assumption, Halstead joked to a reporter as he gathered his papers and prepared to leave, is that the dispute over the Baltimore tunnel fire isn’t likely to let up soon.