Disaster by Design/ Safety by Intent #36
Disaster by Design
Nuclear plant owners are required to develop plans for responding to accidents that describe actions to be taken by workers onsite as well as describing communications to local, state, and federal organizations so they can taken actions offsite. Among other things, the emergency plans detail when to activate the sirens that warn people in the community about an accident at the plant.
Key elements in the emergency plans are Emergency Action Levels (EALs). The EALs are not new aspects—they have been around since at least November 1975, or more than three years before the March 1979 accident at Three Mile Island.
The Nuclear Regulatory Commission has four emergency classification levels: Unusual Event, Alert, Site Area Emergency, and General Emergency in increasing order of severity. The EALs are pre-determined, site-specific, observable thresholds for conditions that place a plant into an emergency classification. EALs are things such as instrument readings, equipment status indications, analytical results, and entries into emergency procedures that enable workers to determine when emergency declarations are necessary.
Timely declaration of an emergency and proper classification of its severity is important to the success of the emergency response. The more severe the emergency, the greater the resources applied in response. When the emergency declaration is late or if the classification level is less than the severity, the response might fail to adequately protect the public.
EALs have been around for decades. For example, the Nuclear Energy Institute (NEI) transmitted Revision 4 to its guidance procedure for EALs to the NRC in January 2003. In July 2003, the NRC issued Revision 4 to its Regulatory Guide 1.101, “Emergency Planning and Preparedness for Nuclear Power Reactors,” to indicate that plants owners can apply the methods described in the NEI guidance document as a way to comply with emergency planning regulations. The NRC sent Regulatory Issue Summary 2003-18 to all plant owners in October 2003 about the agency’s endorsement of the NEI guidance document.
Same Page, But Different Book?
A memorable scene from the 1967 feature film “Cool Hand Luke” starring Paul Newman has the head of a prison work detail informing Newman and other convicts about the “failure to communicate.” Despite the close collaboration between the nuclear industry and its regulator that produces guidance documents prepared by the former and endorsed by the latter, subsequent violations of emergency planning requirements suggest that if they are all on the same page, they are in different books. For example:
One of the EALs specified that workers take the data on radiation readings and assess within 15 minutes whether the criteria for declaring a Site Area Emergency have been met. But on July 20, 2004, workers took 2 hours and 40 minutes to complete the 15-minute radiological assessment.
During an emergency drill on February 7, 2006, the Station Emergency Manager mistakenly classified the simulated event as a Site Area Emergency, contrary to the EALs.
River Bend (LA)
The NRC sanctioned the plant owner on September 7, 2006, after its inspectors determined that workers had not implemented adequate compensatory measures when seismic monitoring instruments were known to be out of service at times in 2004 and 2005. Some of the EALs depended on earthquake magnitudes from the seismic monitoring instruments. Workers knew that the instruments were inoperable for extended periods, but had neither provided substitute instruments nor revised the EALs with alternate means for determining the proper response to an earthquake.
The NRC’s inspectors found that workers improperly revised the EALs and, as a result, reduced the effectiveness of the emergency response plans. The NRC informed the owner on October 12, 2007, that the violation normally would result in a $130,000 fine, but that the agency was exercising enforcement discretion and not imposing the fine.
The NRC’s inspectors found that the radiation levels specified in two of the EALs were greater than the maximum range of the monitoring instruments for the parameters. If would be like driving a car with a speedometer having a scale of 0 to 40 miles per hour and trying to decide whether you were complying with a 55 mph speed limit sign. The NRC sanctioned the owner in October 2008 for EALs requiring information that workers could not possibly obtain.
Prairie Island (MN)
The NRC’s inspectors found in April 2010 that the radiation levels specified in two of the EALs were greater than the maximum range of the monitoring instruments for the parameters and would prevent an Alert from being declared when plant conditions warranted it.
Crystal River 3 (FL)
The NRC’s inspectors found in June 2011 that the EAL value for radiation releases to the air that would result in a General Emergency being declared was greater than the instrument scale on the monitor for that release pathway. Consequently, workers would be unable to recognize during an accident that radiation being released to the atmosphere warranted declaring a General Emergency.
Columbia Generating Station (WA)
The NRC sanctioned the owner in October 2012 for mistakes in the calculations for the values of radiation releases to the environment specified for the EALs resulting in declarations of a Site Area Emergency and a General Emergency.
Calvert Cliffs (MD)
The NRC sanctioned the owner on October 27, 2014, for an inaccurate calculation supporting the replacement of the main steam line radiation monitors on Unit 2. The calculation error resulted in the EAL threshold for declaring a General Emergency to be lower than it should have been. The wrong EAL threshold could have lead workers to declare a General Emergency when plant conditions did not require the highest emergency classification.
Safety by Intent
It’s troubling that the number of EAL-related violations between 2004 and 2014 (which, by the way, is an abridged listing) is so high. One might expect that the countless tests, inspections, and exercises conducted between 1974 and 2004 would have eliminated virtually all the problems. One would clearly be wrong.
And one might expect that all the collaboration between the nuclear industry and its representative that resulted in the revised EAL guidance endorsed by the NRC in 2003 provided the foundation for a decade free of EAL-related problems. One would clearly be wrong.
It’s also troubling that violations at one nuclear plant did not result in workers finding, and fixing, identical problems at their plants. For example, the NRC sanctioned Kewaunee’s owner in 2008 for using values in EALs greater than the instrumentation could indicate. The NRC sanctioned the owners of Prairie Island in 2010 and Crystal River 3 in 2011 for the same problem. One might expect that owners, who purport to have safety as their utmost priority, would respond to a safety problem elsewhere by determining whether their plants had the same vulnerability. One would clearly be wrong.
While the EAL-related problems might prevent emergency sirens from sounding when needed to protect the public, the nature and volume of EAL-related problems actually sounds another alarm—the emergency plans are not as reliable as they need to be. The nuclear industry and the NRC owe it to the public—the millions of Americans living within 10 miles of the nation’s nuclear power reactors—to heed this loud, persistent alarm and take the steps needed to make the emergency plans a reliable safety net.
UCS’s Disaster by Design/Safety by Intent series of blog posts is intended to help readers understand how a seemingly unrelated assortment of minor problems can coalesce to cause disaster and how effective defense-in-depth can lessen both the number of pre-existing problems and the chances they team up.