Federal Panel: Dirty Bomb Cleanup Need Not Follow U.S. Cancer Rules

Authorities hunt for radioactive substances during a 2011 dirty bomb drill in New York City. An upcoming report commissioned by the U.S. Homeland Security Department is expected to recommend significantly less stringent cleanup levels after a radiological attack than are required for other sites contaminated by dangerous materials (AP Photo/Seth Wenig).
Authorities hunt for radioactive substances during a 2011 dirty bomb drill in New York City. An upcoming report commissioned by the U.S. Homeland Security Department is expected to recommend significantly less stringent cleanup levels after a radiological attack than are required for other sites contaminated by dangerous materials (AP Photo/Seth Wenig).

WASHINGTON – A new federally funded report is likely to recommend that contamination from a so-called “dirty bomb” should not have to be cleaned up as thoroughly as hundreds of existing radioactive sites throughout the United States, even though official estimates suggest this change would dramatically increase the risk of cancer in people living in the affected area.

In the event of such an attack, a new, more flexible approach to cleanup will be needed in order to deal with economic realities, the report, sponsored by the U.S. Homeland Security Department and expected sometime next year, will urge. Detractors, however, say the government’s conventional approach already allows for such flexibility – without the expense to public health.

Since the 1980s, cleanup of the nation’s most heavily contaminated properties -- including former nuclear weapons manufacturing and testing facilities owned by the Energy Department – has been governed by the U.S. Environmental Protection Agency’s Superfund program. Pursuant to Superfund guidelines, remediation is designed so that 1 out of 10,000 people exposed to a site for 30 years would be expected to develop cancer in a worst-case scenario. One in 1 million people would be expected to develop cancer in the best possible situation.

The head of the panel that is writing the new report says he and his colleagues do not believe these longstanding guidelines need to be followed in the event of an attack involving a dirty bomb or other illicit nuclear device, however.

Instead, they will suggest that a radiation dose to the human body of between 100 and 2,000 millirems per year be the target that officials keep in mind when deciding on cleanup actions, said S.Y. Chen, a senior environmental engineer at Argonne National Laboratory in Illinois.

Roughly 1 in 23 people would be expected to develop cancer from receiving a 2,000 millirem dose of radiation annually for 30 years, based on estimates from the International Commission on Radiological Protection, a private, nongovernmental organization whose work Chen cites as the basis for his recommendations. Approximately 1 in 466 people would be expected to develop cancer from an annual dose of 100 millirems over the same time period, according to calculations Global Security Newswire conducted using ICRP projections.

“It is just ethically indefensible,” Daniel Hirsch, a nuclear policy lecturer at the University of California-Santa Cruz told GSN. “Anyone proposing such a thing should go to jail.”


Chen counters that EPA guidelines are not applicable to terrorist situations by arguing that the Superfund program was developed to deal with contamination that is more limited in scope. The experience of the Japanese in the wake of last year’s earthquake- and tsunami-induced nuclear power plant meltdowns proves the need to consider economic factors in carrying out a massive cleanup, he said.

“Bring Superfund to Japan and see how it’s going to work. It will fail miserably,” Chen said in a recent interview with GSN. In the event of a dirty bomb or nuclear attack, “it won’t just be a Superfund-like community where several acres are contaminated,” he said. “Everywhere everybody will get disrupted big time. You have to worry about your jobs, you worry about business, you worry about your livelihood on a daily basis. So all of the sudden it’s no longer a contamination issue, it’s a bigger society issue that everyone has to cope with.”

Many Superfund sites are actually larger than what federal officials and other experts typically describe when they talk about how much land they would expect a dirty bomb to contaminate, however. An existing DHS guide that the forthcoming report is meant to supplement describes the area likely affected by a dirty bomb as ranging between “a single building or city block” to “conceivably several square miles.

“However, most experts agree that the likelihood of impacting a very large area is low,” the DHS guide says.

In 2002 testimony to the Senate Foreign Relations Committee, Federation of American Scientists President Henry Kelley presented three hypothetical dirty bomb scenarios. The first two, which involved terrorists using TNT to explode a medical gauge containing radioactive cesium and a source of radioactive americium used in oil well surveying, contaminated areas slightly larger than one square mile. In the third, which Kelley said was less likely, a piece of radioactive cobalt from a food irradiation plant contaminated an area of about 386 square miles.

By comparison, the former nuclear weapons production facility at Hanford, Wash., that the Energy Department is cleaning up pursuant to Superfund is 586 square miles. The Savannah River Site in South Carolina, also undergoing Superfund cleaning, is 310 square miles.

“It’s called Superfund for a reason – these are big sites with big problems, the nation’s most contaminated sites,” Hirsch said.

The existing DHS guide and the anticipated supplement confuse the issue by addressing dirty bombs together with improvised nuclear devices, the latter of which would be expected to cause a far greater degree of devastation, Hirsch contends.

“If you have an [improvised nuclear device] you’re going to be missing a portion of your city. If you have a dirty bomb it’s a tiny chemical explosion like a pipe bomb and you’ve got radiation that’s been released over a few blocks,” he said.


Chen argues that using the 100 to 2,000 millirem per year dose range as the target for remediation goals will give stakeholders the flexibility to prioritize the use of limited cleanup resources in the face of widespread contamination. While a schoolyard might be cleaned to a more stringent level, higher amounts of radiation could be tolerated elsewhere, he said.

“You only have so much technology, manpower, money and supply,” Chen said. Prioritizing cleanup projects “will take a lot of effort and stakeholder involvement. It’s not going to be a government prescribed approach like we had before.”

The Superfund remedy selection process does involve stakeholder input, however. Cleanup plans are subject to public review and comment before they are finalized and Superfund rules dictate that cost-effectiveness, community acceptance and state government approval be among the criteria considered when deciding on how best to deal with contamination.

Superfund goals can also be adjusted depending on the expected use for a particular piece of land, in part because the amount of hours per week a person would be expected to spend at a location varies depending on its purpose. “Something you know is going to be used for agricultural [or residential] uses you clean up to a stricter standard than some place that’s only going to be industrial,” Hirsch said. “All that flexibility is in Superfund.”

Carl Spreng, a project manager at the Colorado Public Health and the Environment Department, noted that under Superfund, the number of years regulators assume a person will be exposed to a site can also be adjusted to account for site specific circumstances, and cleanup goals adjusted accordingly. While 30 years is considered a conservative rule of thumb for how long Americans are likely to live in a particular location, at some sites people are expected to spend less time, and at others more, he said.

Spreng said that when DHS officials proposed in past years to set an acceptable post-dirty bomb dose range similar to what Chen is now suggesting, state officials throughout the country “were frankly shocked.”

The dose range the new report is expected to suggest is “way outside the numbers that we would consider safe and have argued for many years,” Spreng said. “We’d still have significant concerns with numbers like those.”


Chen’s panel is writing the report for the privately run National Council on Radiation Protection and Measurements with funds from the U.S. Homeland Security Department. The report is intended to expand on a controversial document Homeland Security published in 2008.

Commonly referred to as a “protective action guide” or “planning guidance,” the document was meant to advise responders at the federal, state and local levels in the event of a radiological attack.

Along with scenarios involving a dirty bomb -- a crude weapon terrorists would use to disperse radioactive material over a relatively small area through the detonation of conventional explosives – the DHS guide and the ensuing NCRP report are also intended to advise the response to improvised nuclear devices that could produce levels of destruction closer to that of a traditional atomic bomb.

In the initial aftermath of such attacks, the DHS guide recommends largely following previously established EPA guidelines for nuclear emergencies. During this time period – the days and weeks immediately following an incident -- responders would have to make quick decisions regarding sheltering, evacuation and contaminated food and water supplies.

When it comes to long-term efforts to clean up and reclaim areas affected by the radiological blast, however, the DHS guide parts ways with standard U.S. practice. Rather than follow Superfund protocol, it recommends interested stakeholders follow a process called “optimization” when making decisions about how contaminated areas should be cleaned up or otherwise managed. Optimization involves weighing factors such as human health and public welfare against cost and economic impact, the guide says.

However, the DHS guide provides little explanation as to how this optimization approach would actually work in the real world. Unlike Superfund, the system the DHS guide describes includes no numerical guidelines – such as a specific risk or dose range that a site should comply with when cleanup is complete.

To provide more detail on how optimization would work, Homeland Security in 2010 began providing funds for the NCRP panel to write the forthcoming report on remediation. In addition to Chen, the panel consists of experts on a wide range of topics, including health physics, economics and public communication.

The optimization approach was already attracting strong opposition from critics both in and outside of government. A coalition of more than 60 public health and nuclear watchdog groups signed a letter condemning the Bush administration’s 2008 attempt to incorporate the DHS approach into an EPA guide on responding to a broader array of radiological incidents. The Obama administration ultimately delayed execution of the Bush plan.

Internal e-mail messages the agency later released under the Freedom of Information Act showed that some EPA staff and state government officials had also opposed the optimization concept and its potential inclusion in the EPA document. A revised version is pending review at the White House Management and Budget Office.


At the time, critics feared the lack of numerical cleanup guidelines in the DHS optimization guide would lead to decisions that the public can be exposed to levels of radiological contamination far above what EPA rules normally allow.

Indeed, the high end of the dose range that Chen is now suggesting – 2,000 millirems per year, a 1 in 23 cancer risk from 30 years of exposure to a remediated dirty bomb attack site -- is more than 400 times less stringent than the worst-case 1-in-10,000 cancer risk the government would normally accept. It is 43,000 times less stringent than Superfund’s 1-in-1 million ideal.

National Academy of Sciences projections the Environmental Protection Agency adopted last year suggest an even greater cancer risk. A 2,000 millirem per year dose for 30 years would cause 1 in 15 people to develop cancer, using NAS figures.

Hirsch, who as president of the watchdog group Committee to Bridge the Gap led the opposition to including optimization in the EPA guide in 2008, likens receiving the high end of Chen’s dose range for 30 years to getting 10,000 chest X-rays, “with no medical benefit.”

Arjun Makhijani, president and senior engineer at the Institute for Energy and Environmental Research, said the cancer risk could decline somewhat over the years due to radioactive decay and “various types of erosion.” Even with this caveat, however, the risk at the upper end of the proposed dose range is still high, he said.

“Plus risks to children are higher than the average and for some radionuclides much higher,” Makhijani added.

David Brenner, director of the Center for Radiological Research at Columbia University, noted, however, that the ICRP recommendations Chen is looking to adopt urge selecting cleanup targets from the lower end of the 100 to 2,000 millirem per year dose range. Even if exposures have already been reduced below the range, cleanup can continue “as long as there is room to reduce exposures further in conformity with the optimization process,” the ICRP recommendations say.

“I think their picture is that one should get down below [100 millirems per year] as quickly as is reasonably achievable,” Brenner added. “The scenario of [2,000 millirems per year] every year for 30 years … seems quite inconsistent with that picture.”

Even at the low end, however, Chen’s suggested dose of 100 millirems per year – a 1 in 466 risk over 30 years -- carries a cancer risk 20 times greater than the worst-case scenario for remediated Superfund sites. It is 2,000 times less stringent than the ideal.

In Colorado, state regulators consider the lower end of Chen’s proposed range to be the upper end of what they would permit, according to Spreng, the state official. The state uses a 25 millirem per year dose as a target for residential cleanups, with 100 millirems per year considered the upper limit.

Chen argued the Superfund approach to cleanup is ill-equipped to deal with some of the long range problems that could follow a radiological attack, such as the problem of wildlife wandering into contaminated areas and then later entering the human food supply. He argued that the flexibility of the optimization approach makes it more adept to dealing with such continuous, long term issues than Superfund.

“It’s different for Superfund because with Superfund you bring the bulldozer, you take away the contamination, you wash your hands and walk away and say I’m done,” Chen said. “You will not get done with this.”

At the Savannah River Site, however, the Energy Department has run a monitored deer and hog hunting program since 1965. Animal remains are scanned for cesium contamination before a hunter is allowed to take them off the property.

“Monitoring road kill is a standard approach at [Superfund] sites,” added Hirsch. In addition, EPA officials review completed Superfund cleanups – which often take years or even decades to finish – every five years to ensure that they are still effectively protecting human health.


A major concern among watchdog groups is that the DHS guide, combined with the forthcoming NCRP report, will establish a precedent that will relax remediation standards not only for areas contaminated by dirty bombs, but also for the more routine cleanup of nuclear weapons facilities owned by the Energy Department and other sites with radioactive contamination.

The draft EPA guide put on hold by the Obama administration would have extended application of the optimization approach beyond just dirty bomb and improvised nuclear device attacks, watchdog groups complained. Under the document, optimization would have been the preferred approach to cleaning up after a wide range of incidents, including accidents and attacks at nuclear power plants and industrial facilities that use radioactive material.

The DHS and NCRP documents are the “camel’s nose under the tent,” according to Hirsch. Once federal reports on dirty bombs adopt the dose range Chen suggests, it becomes easier for government agencies and private parties responsible for decontaminating other types of radioactive residue to argue that they should not be held to higher standards, he said.

Further exacerbating activists’ concern is the fact that last month, the NCRP panel dropped the phrase “terrorism events” from the title of its forthcoming report and replaced it with the word “incidents.” Hirsch said this suggests the panel is looking to apply optimization to a broader range of scenarios. He noted that officials with the Energy Department, which is responsible for paying for the cleanup of nuclear weapons sites, also sit on the panel.

November 26, 2012

WASHINGTON – A new federally funded report is likely to recommend that contamination from a so-called “dirty bomb” should not have to be cleaned up as thoroughly as hundreds of existing radioactive sites throughout the United States, even though official estimates suggest this change would dramatically increase the risk of cancer in people living in the affected area.