A conventional approach to safety is based on the concept of design events. A building code might say, for example, that a building should be able to survive a 7.0 earthquake. This approach has been basic to the regulation of nuclear reactors. As the interim report of the post-Fukushima NRC task force explains:
The regulation also requires that design bases . . . reflect (1) appropriate consideration of the most severe of the natural phenomena that have been historically reported for the site and surrounding region, with sufficient margin for the limited accuracy and quantity of the historical data and the period of time in which the data have been accumulated, (2) appropriate combinations of the effects of normal and accident conditions with the effects of the natural phenomena, and (3) the importance of the safety functions to be performed. p. 25
The report points out two flaws with this approach. The first issue is selection of the design-basis event. At Fukushima, the design-basis tsunami was chosen too optimistically and without full consideration of the historical record. p. viii It is also difficult to ensure uniform treatment since the method for picking the design-basis event may vary between facilities. p. 20 Selection of the design-basis event may be arbitrary. For instance, as Doug Kysar has explained, the planner for the New Orleans flood control system excluded some historic hurricanes from their calculations on the theory that those hurricanes were outliers.
Second, this approach does not encourage planning for the unexpected. As the Task Force explains:
Whether through extraordinary circumstances or through limited knowledge of the possibilities, plants can be challenged beyond their established design bases protection. In such circumstances, the next layer of defense-in-depth, mitigation, is an essential element of adequate protection of public health and safety. Mitigation is provided for beyond-design-basis events and severe accidents, both of which involve external challenges or multiple failures beyond the design basis. p.20
Finally, use of the design-basis event may be misunderstood to imply that the facility is risk-free. It is notorious that communities often build up behind levees that are designed to block the 100-year storm. The public believes that no breach can be expected for a century, whereas the standard actually means that there is a one-percent chance of flooding every year.
Design-basis planning is a crude tool. It may be adequate in some settings but not in major projects that are subject to potential catastrophic failures. The Task Force advises greater use of probabilistic risk analysis, to consider a broader range of risks, and also the use of “defense in depth” to deal with contingencies beyond the design-basis event. p. 21 It would be wise to heed these recommendations, not only in the area of reactor safety, but also in other contexts such as flood planning for urban areas and deepwater drilling.
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Daniel Farber | March 12, 2012
A conventional approach to safety is based on the concept of design events. A building code might say, for example, that a building should be able to survive a 7.0 earthquake. This approach has been basic to the regulation of nuclear reactors. As the interim report of the post-Fukushima NRC task force explains: The regulation […]
James Goodwin | March 9, 2012
Inside EPA is reporting that yet another critical EPA rulemaking is now being delayed indefinitely. This time it’s the agency’s rulemaking to codify a draft guidance clarifying whether Clean Water Act protections apply to wetlands and other marginal waters. EPA had projected on its online rulemaking gateway that it expected to issue a proposed rule […]
Sidney A. Shapiro | March 8, 2012
In 1975, Indiana lawmakers joined a small but growing group of state legislatures passing aggressive medical malpractice “reforms.” Indiana’s law capped damages that victims of medical malpractice can recover at $500,000 and eliminated damages for pain-and-suffering altogether, Frank Cornelius, a lobbyist for the Insurance Institute of Indiana, played a role in helping pass this legislation. […]
| March 7, 2012
Last week, the Supreme Court heard oral argument in Kiobel v Royal Dutch Petroleum, the case asking whether corporations can be liable in federal court for violations of international human rights law. In the decision under review, the Second Circuit – unlike every other circuit court to consider the question – had held that they […]
Daniel Farber | March 7, 2012
Cross-posted from Legal Planet. The U.S. Court of Appeals for the Fifth Circuit has upheld a district court ruling that the federal government is liable for damage from the Katrina storm surge that went up the MRGO canal into the city. As I read the opinion, it is limited in three ways. First, it is […]
Ben Somberg | March 6, 2012
On November 7 of last year, EPA sent the White House Office of Information and Regulatory Affairs (OIRA) a rather important proposed rule – one that will, in some way, limit greenhouse gas emissions from new power plants. The Greenhouse Gas New Source Performance Standard for Electric Generating Units for New Sources has now been […]
Robert Verchick | March 5, 2012
The BP Oil Spill case settled! Well, part of it. The smaller part. But, still, we must count this a victory for U.S. District Judge Carl Barbier, whose reported 72 million pages of assigned reading will inevitably be shaved down. (Does this man have an iPad?) On Friday evening the court announced that BP had […]
Rena Steinzor | March 2, 2012
The toll: An estimated 6,500 to 17,967 premature deaths, 9,867 non-fatal heart attacks, 3,947 cases of chronic bronchitis, and more than 2.3 million lost work and school days. That’s just a partial tally of the costs Americans will bear because of unjustified delays in two critical health and safety regulations. More broadly, the Administration’s Fall […]
Sidney A. Shapiro | February 28, 2012
A new Pew public opinion poll published last week shows substantial public support for specific types of regulation, but skepticism about regulation in general. While 70-89% of the public would either expand or keep current levels of five specific types of regulation, 52% say government regulation of business usually does more harm than good as […]