ML13112A266
| ML13112A266 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 12/10/2012 |
| From: | Lochbaum D Union of Concerned Scientists |
| To: | Boska J Plant Licensing Branch II |
| Boska J | |
| References | |
| Download: ML13112A266 (2) | |
Text
December 10, 2012 John Boska, Project Manager Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555
Subject:
Fair weather verification of protection against foul weather?
Dear Mr. Boska:
I called into last months public meeting between the NRC staff and the Oconee licensee. During this call, there was some discussion about the flood wall protecting the standby shutdown facility (SSF). It was mentioned that there are no doors in this flood wall with access to the SSF provided by staircases on either side of the wall.
A licensees representative (I didnt catch the name of this speaker) reported that earlier in his career as an operator, he had been periodically trained in the manual actions required to be taken at the SSF to verify they could be completed within the fairly short time frames required (less than 30 minutes).
There was also discussion of probable maximum precipitation (PMP) as being one of the scenarios during an event for which the SSF might be relied upon.
Upon further reflection, this information led me to question the efficacy of timeline verifications during fair weather and their applicability under more adverse conditions. For example, onsite flooding could seriously impede workers efforts to perform required tasks within the SSF. Even if onsite flooding doesnt overtop the flood wall around the SSF, several feet of flood waters could seriously slow travel to the SSF. Likewise, if the event involves an earthquake, downed power lines not yet de-energized could also impede travel.
Based on the meeting, it seems there are a handful of operator actions that must be taken within a relatively short time in order to prevent core damage. It also seems that the periodic training demonstrates that these steps could be taken within the allotted times, but with little margin under perfect conditions. This makes it difficult to believe these important steps could be taken in time under the imperfect conditions associated with onsite flooding or other external hazards, such as an earthquake.
December10,2012
Page2 I trust the NRC will cast a very critical eye on these timelines to determine whether they are also feasible in practice and not just during unrealistic training exercises.
Sincerely, David Lochbaum Director, Nuclear Safety Project PO Box 15316 Chattanooga, TN 37415 (423) 468-9272, office (423) 488-8318, cell