ML11263A066

E-mail from D. Doyle, NRR to R. Auluck, NRR on Basemat and Containment Question

ML11263A066
Person / Time
Site:	Salem, Hope Creek
Issue date:	02/09/2011
From:	Dan Doyle Division of License Renewal
To:	Rajender Auluck Division of License Renewal
References
FOIA/PA-2011-0113
Download: ML11263A066 (2)

Text

Doyle, Daniel From: Doyle, Daniel Sent: Wednesday, February 09, 2011 8:08 AM To: Auluck, Rajender.

Cc: Wentzel, Michael; Perkins, Leslie; Lehman, Bryce; Sheikh, Abdul

Subject:

RE: Basemat and containment question Follow Up Flag: Follow up Flag Status: Completed Categories: Salem Hope Creek Ok, thanks Raj.

Bryce, I need a basic explanation about containment to respond to the comment in my original e-mail below. I will come talk to you about this today.

Thanks, Dan Doyle Project Manager Division of License Renewal U.S. Nuclear Regulatory Commission daniel.dovle(Dnrc.,qov (301) 415-3748 From: Auluck, Rajender Sent: Wednesday, February 09, 2011 8:05 AM To: Doyle, Daniel Cc: Wentzel, Michael; Perkins, Leslie; Lehman, Bryce; Sheikh, Abdul

Subject:

RE: Basemat and containment question

Dan, Bryce will be able to help you and coordinate the RASB response.

Raj From: Doyle, Daniel Sent: Wednesday, February 09, 2011 7:57 AM To: Auluck, Rajender Cc: Wentzel, Michael; Perkins, Leslie

Subject:

Basemat and containment question

Raj, We received the following comment from the state of New Jersey for the Salem Hope Creek draft SEIS. Who do you think would be the best person to talk to in order to provide a response that briefly states how the containment manages the water that flashes to steam in this type of scenario? Thanks Comment SHC-W-14: SAMA - Breakdown of Population Dose by Containment Release Mode for Salem Generating Station / Table 5-4 / Page 5-6 / Line 10.

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For the "Basemat Melt Through (BMT)", population dose is considered negligible. The BMT is a protection system for the basemat of reactor containment buildings in nuclear power stations. The system comprises a structure located in a cavity below the reactor vessel and submerged in water.

The structure comprises staggered layers of stainless steel beams for intercepting molten material escaping from the reactor vessel during meltdown of the reactor core. The system is designed so that the molten material is distributed in thin layers over wings of the beams and transfers its heat to the surrounding water thus affording a rapid quenching of the molten core and safeguarding the integrity of the basemat.

Would there be any chance, even within the basemat system of staggered layers of steel beams, of a flash to steam of the molten material and potential release to the atmosphere augmentinglcausing a potential contribution to population dose? Have there been model studies done to confirm the report's claims of negligible contribution to population dose? The steam generated during this core melt must be relieved somewhere.

Response: (check with a safety reviewer who is familiar with the containment for an explanation how water flashing to steam is managed)

Dan Doyle Project Manager Division of License Renewal U.S. Nuclear Regulatory Commission daniel.doYle(c.nrc.qov (301) 415-3748 27