That gets into some pretty profound discussions of just what "risk" is.

The current benchmark (e.g., used in the IPCC's own assessments of carbon-neutral energy options) is of lives per GW generation. I find this naive on numerous counts, e.g., my citation of the Banqiao disaster -- horrible if you were caught up in it (though also note: the bulk of the deaths werev from disease and starvation in the aftermath, the acute toll from the inundation was ~40-50k).

Virtually all deaths due to conventional processes -- physical, heat, trauma, even chemical -- are fairly ameliorable by direct precautions. Even in the case of a massive dam failure -- Banqiao, Johnstown, Vajont -- advance warning of a few minutes would have reduced fatalities tremendously, and with hours or days, all but entirely. Each of these disasters was precipitated by clear warning signs, though they were unheeded, for various reasons. In the Johnstown and Vajont cases, state of the art in engineering and geology was a major component. Perverse incentives to plant operators existed in all cases.

Looking at instances of explosions also suggests that warning, evacuation, and shelter could save virtually all lives, assuming a proper understanding of circumstances. Halifax, Canada, Galveston, TX, West, TX, Martinez, CA, Tianjin, China, and Lac Megantic, Canada all represented substantial loss of life which could have been avoided through both better advanced risk management and notice in advance of the precipitating disasters. Contrast the Pepcon disaster, among the largest non-nuclear blasts ever. Immediate deaths, though, were only two (another 370 or so injured), in large part due to the facility's isolation from any surrounding structures.

By contrast, long-term chronic exposures can be quite debilitating. Minimata, Japan, Love Canal, Hinkley, CA ("Erin Brokovich"), Bhopol, India, Agent Orange throughout Vietnam and SE Asia, and industrial contamination throughout China, will likely be with us for a long, long time. Flint, MI, can be added to that list.

Chemicals can generally be mitigated through binding and sequestration operations, nucleotides are more difficult. Long-term low-level chronic emissions, or perhaps worse: punctuated equilibria, concern me.

The bigger concern I have though is for systemic failure. Nuclear energy provisioning, particularly based on very sparse fuel sources (uranium from seawater, thorium from rare earths mining) creates a long-term dependence on a large and potentially fragile technological stack. By contrast, wind, solar, and hydroelectric power are rather simpler, and even geothermal is fairly straightforward.

"Complexity is the enemy of reliability" is a phrase first occurring in The Economist newspaper, January 18, 1958. It's been repeated, usually as "complexity is the enemy", many times since, though I suspect those citing it don't know the origins (my first encounter was through Eric S. Raymond's writings).

Creating a civilisation-supporting technological stack that isn't complex seems a strong goal. And quantifying systemic global risk part of the problem.

http://books.google.com/books?id=aDsiAQAAMAAJ&q=%22complexit...

https://www.reddit.com/r/dredmorbius/comments/24cxgc/program...