Wednesday, October 24, 2012

NNSA's Safety Culture: Does It Cost Too Much?

The 24th Annual "Nuclear Weapons Complex Waste Management & Cleanup Decision Makers’ Forum" took place recently, (October 15-18, 2012), in Jacksonville, Florida. The keynote address was presented by Peter Winokur, Chairman, Defense Nuclear Facilities Safety Board (DNFSB). A summary of Winokur's address, entitled "DNFSB, DOE and the Contractors: Roles, Responsibilities, and the Road Ahead", follows:

Is the DOE defense nuclear facilities complex safer now than when the Board commenced operations in the late 1980's? Yes! ... However, we cannot ignore current and emerging challenges ... and the federal commitment to protect the health and safety of workers and the public. Past success is a poor reason to decide to lessen present safeguards ... and giving up now on any of the elements of success would be foolish.

History teaches us that organizations have responded to budgetary pressures by accepting lower standards in their daily operations, especially safety, maintenance, and training; viz., often, by allowing their safety culture to degrade.

Beset by budgetary stringencies, DOE is concerned that it has become too risk-adverse and that its safety strategies have become too burdensome. DOE seems to be signaling that it is now willing to accept more risk. Moreover, DOE has also failed to learn important recent lessons and to implement related corrective actions on major design and construction projects.

Apropos of which, there is an old Chinese proverb: to know the road ahead, ask about the experiences of those who have arrived along that road.

In particular, history teaches that a broken safety culture has all too often led to serious accidents:
(For each of the following six events, descriptive material from Wikipedia has been added.)

1) Tokai-mura criticality accident

    In 1999 three workers received high doses of radiation in a small Japanese plant preparing fuel for an experimental reactor. Two of these workers died from their exposure. The accident was caused by concentrating excessive amounts of enriched uranium (~20% U235), leading to a criticality excursion (a limited uncontrolled nuclear chain reaction), which continued intermittently for 20 hours.

    A total of 119 people received a radiation dose over 1 mSv from the accident. Three operators' doses were above all permissible limits and two of the doses proved to be fatal. The cause of the accident was "human error and serious breaches of safety principles", according to IAEA.

2) Davis-Besse NPS

    Davis-Besse Nuclear Power Station is a nuclear power plant in Oak Harbor, Ohio. It has a single pressurized water reactor, also known as a light water reactor. As of 2011, it was being operated by the FirstEnergy Nuclear Operating Company subsidiary of FirstEnergy Corp.

    On March 5, 2002, maintenance workers discovered that corrosion had eaten a football-sized hole into the reactor vessel head at the Davis-Besse plant. Although the corrosion did not lead to an accident, this was considered to be a serious nuclear safety incident. The Nuclear Regulatory Commission kept Davis-Besse shut down until March 2004, so that FirstEnergy was able to perform all the necessary maintenance for safe operations. The NRC imposed its largest fine ever -- more than $5 million -- against FirstEnergy for the actions that led to the corrosion. The company paid an additional $28 million in fines under a settlement with the U.S. Department of Justice.

    According to the NRC, Davis-Besse has been the source of two of the top five most dangerous nuclear incidents in the United States since 1979.

3) NASA's two space shuttle disasters

    The Space Shuttle Challenger disaster occurred on January 28, 1986, when the spacecraft broke apart 73 seconds into its flight, leading to the deaths of its seven crew members. Disintegration of the vehicle began after an O-ring seal in its right solid rocket booster failed, allowing pressurized hot gas from within the solid rocket motor to impinge upon the adjacent hardware and external fuel tank. This led to the structural failure of the external tank, and aerodynamic forces then broke up the orbiter. The O-ring had been previously identified as a vulnerable component, but engineers who had sounded the alarm were ignored by management.

    The Space Shuttle Columbia disaster occurred on February 1, 2003, when the spacecraft broke up during reentry into the atmosphere, resulting in the death of all seven crew members. The loss of Columbia was a result of damage sustained during launch when a piece of foam insulation broke off from the external fuel tank. The debris struck the leading edge of the left wing, damaging the Shuttle's thermal protection system, which shields the vehicle from the intense heat generated during reentry. It had long been recognized that foam shed during launch could jeopardize the integrity of the heat shield, but this had been discounted by management as an unlikely event.

4) BP Texas City Oil refinery disaster

    On March 23, 2005, a fire and explosion occurred at BP's Texas City Refinery in Texas City, Texas, killing 15 workers and injuring more than 170 others. BP was charged with criminal violations of federal environmental laws, and has been subject to lawsuits from the victims' families. The Occupational Safety and Health Administration slapped BP with a then-record fine for hundreds of safety violations, and subsequently imposed an even larger fine after claiming that BP had failed to implement safety improvements following the disaster.

5) Deepwater Horizon disaster

    The Deepwater Horizon oil spill in the Gulf of Mexico flowed unabated for three months in 2010, and is the largest marine spill in the history of the petroleum industry. It stemmed from a sea-floor oil gusher caused by the 20 April 2010 explosion of the Deepwater Horizon drilling rig. The rig explosion killed 11 men working on the platform and injured 17 others. On 15 July 2010, the gushing wellhead was capped, after it had released about 4.9 million barrels of crude oil. The platform was owned by Transocean, and operated for BP. Both transocean and BP have been heavily criticized for their failure to foresee, and to prepare for such an accident.

6) Fukushima Dai-ichi disaster

    The Fukushima Dai-ichi nuclear disaster encompassed a series of equipment failures, nuclear meltdowns, and releases of radioactive material at the Fukushima I Nuclear Power Plant. The nuclear disaster was caused by the Tohoku earthquake and tsunami of 11 March 2011, and is the largest such event since the Chernobyl disaster of 1986.

    It has been accepted by Power Plant authorities that the safeguards in place prior to the disaster were inadequate; i.e., in view of the fact that the reactor complex had been sited in an area where more than one devastating tsunami had occurred during the last ~500 years.

Winokur concluded his talk by pointing out that:

a) Even under severe budget constraints, DOE must continue to ensure that its priorities are well-balanced between mission and safety concerns.

b) DOE's current successful safety strategies have been developed with effort over many years and must not now be cast aside or downgraded.

c) Design basis accidents and beyond design basis accidents have already been analyzed extensively and should now be treated as real and imminent threats.

For more on this topic, see my blogpost of July 14, 2012 entitled "DNFSB Disagrees with NNSA Analysis"; also, the blogpost of Februrary 27, 2012 entitled "NRS Studies NNSA and its Nuke labs."

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