Nuclear Waste Pools & Solar Flares

This video is like a freak show from the 1970's or something:

The U.S. NRC (I can't address all countries) has looked into solar flares and found that they might cause a Station Black Out (SBO), but that plant's diesel generators would be unaffected.  So an SBO caused by a solar flare is no different than any other SBO that a plant has to show the ability to maintain safety.

Here is a letter on the subject written a few months ago by the NRC to a U.S. Congressman. 

This is an excerpt from a relicensing document for Hope Creek and Salem plants in which the issue was raised.  It is discussing core cooling (bigger heat load) as opposed to spent fuel pool cooling but the principles are common to both:

"With respect to the comment’s suggestion that solar storms should be included as an initiating

event for severe accident mitigation alternatives (SAMA), the staff considers the issue as

follows: The SAMA analysis considers potential ways to further reduce the risk from severe

reactor accidents in a cost-beneficial manner. The process for identifying and evaluating

potential plant enhancements involves use of the latest plant-specific, peer-reviewed

probabilistic risk assessment (PRA) study. These risk assessment studies typically show that

loss of offsite power (LOSP) and station blackout (SBO) sequences are among the dominant

contributors to core damage frequency (CDF) for nuclear power plants and account for about 20

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to 50 percent of the CDF. As a result, enhancements to mitigate SBO events initiated by a

LOSP are routinely identified and evaluated in the SAMA analysis. Consideration of SBO

events initiated by a solar storm would not be expected to result in identification of additional

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SAMAs to mitigate LOSP and SBO events since license renewal applicants already perform a

Consideration of solar storms would not be expected to substantially impact the CDF for

LOSP/SBO events because postulated damage to generator step-up transformers would not

affect the operation of the emergency diesel generators (EDGs). The EDGs would function to

cool the reactor core until connections to the electrical grid are reestablished or alternative

means of core cooling are established. Onsite fuel storage is typically sufficient to provide for at

least 7 days of EDG operation and would be replenished during this period, as demonstrated at

the Turkey Point plant following Hurricane Andrew in 1992 (NRC, 1992). Even with a major

disruption in the supply chain, the 7-day period is sufficient for alternative arrangements to be

made to resupply fuel for nuclear power plant EDGs in accordance with the National Response

Framework (see National Response Framework, Emergency Support Function #12 – Energy

Annex, www.fema.gov/pdf/emergency/nrf/nrf-esf-12.pdf). Alternative means of core cooling

would be viable in the longer term, given that core cooling requirements (e.g., required pumped

flow rates) would be substantially reduced days and weeks after reactor shutdown, and given

the substantial industry and Federal resources that would be available to facilitate these

measures.

If there is incompleteness in current PRAs with respect to an underestimate of the frequency or

consequence of solar storm-initiated LOSP/SBO events, the sensitivity analysis performed on

the SAMA benefit calculation would capture the increased benefit that might result from a more

explicit consideration of solar storm-induced events. This analysis typically involves increasing

the estimated benefits for all SAMAs by an uncertainty multiplier of approximately 2 to

determine whether any additional SAMA(s) would become cost-beneficial and retaining any

such SAMA(s) for possible implementation. In summary, the consideration of solar storm44

initiated events would not be expected to alter the results of the SAMA analysis since

enhancements that address these types of events are already considered in the applicants’

search for SAMAs to mitigate SBO/LOSP events, and any potential underestimate of the benefit

of these SAMAs would be captured in existing applications by the use of the uncertaintySAMA benefits.

 search for potential means to mitigate these risk contributors.