Not trustworthy.

A report invalid and inadequate for making safety decisions on the part of politicians and policy makers.

These are among the conclusions reached by a committee of the National Research Council in its evaluation of an updated risk assessment for the National Bio and Agro-Defense Facility (NBAF), which is under construction — but stalled — in Manhattan, Kan.

In a teleconference with reporters today, several members of the committee addressed the deficiencies and 14 findings articulated in its much-anticipated (99-page) report.

The committee said that while the Department of Homeland Security used conventional, widely accepted methods of calculating risks associated with the federal animal disease lab, the way they applied those methods and the assumptions they used were faulty.

For example, DHS independently evaluated safety features of the NBAF and calculated overall risk by averaging the efficacy of those features. The committee found this approach ignored the way safety features are interconnected and depend on one another in certain accidents.

The committee called this “common cause.” Committee chair Greg Baecher of the University of Maryland, College Park, used the example of the Japanese tsunami and its impact on the Fukushima Daiichi nuclear power plant.

“If you look at the accidents in large technogenic systems today, those accidents occur because several safety systems coincidentally failed at the same time. They typically failed because of some common mode or event. In Fukushima, it was a tsunami event that compromised a number of redundant backup systems. 

“When we say the current risk assessment is dependent among all safety systems, that’s what we mean.

“If you don’t’ look at way these safety systems might be affected by common threat to failure, you run the risk of substantially underestimating, possibly by many factors of ten, underestimating risk, and that’s what we think happened here.”

The DHS had estimated the risk from the NBAF at less than 1 percent in its latest safety report.

The committee found the risk assessment so lacking in accuracy and inconsistencies that it was “difficult to determine the degree to which risks were underestimated.”  In many instances, the committee said, “it could not verify (the report’s) results, because methods and data were unevenly or poorly presented.”

Still, Baecher told reporters that the committee’s conclusions did not address the whether the NBAF was safe enough to build. He said that was a political or policy decision, based on how much risk is acceptable.

In 2010, the NRC found the original Department of Homeland Security risk assessment severely flawed.

Congress mandated DHS update that report, and mandated the NRC re-evaluate that update. This report is the NRC’s latest evaluation.

Congress has appropriated $165 million for the $1 billion NBAF project, but construction has been held up pending today’s NRC report.

For more NBAF news, visit the Tracking NBAF page on our partner site kcur.org.