ML061860714

Email from G. Seeman (NPPD) to D. Loveless (Riv), Subject: Service Water Modeling

ML061860714
Person / Time
Site:	Cooper
Issue date:	03/05/2004
From:	Seeman G Nebraska Public Power District (NPPD)
To:	David Loveless NRC Region 4
References
FOIA/PA-2006-0007
Download: ML061860714 (1)

Text

1,David Loveless - RE: Service Water Modeling Dv Lols.ESriWtr denPage 1

-"Seemanr Glei-rA.-<gaseema@nppd.com>-- -

To: "David Loveless" <DPL@ nrc.gov>

Date: 3/5/04 10:51AM

Subject:

RE: Service Water Modeling David, I left a voice message for you yesterday, but I wanted to send the information in an email.

I discussed your question on the failure of both 36MV and 37MV to isolate and the resulting success criteria with Kent and the system engineer.

The system engineer felt that 3 pumps would be successful based on manual initiation of SW flow to the RHR Heat Exchanger which would require isolation of SW flows which are not required.

Our PRA model does not reflect this - low probability of both valves to fail to isolated. Each SW loop is evaluated separately, failure of it's respective isolation valve requires both pumps in the loop.

If you have additional questions, please contact me.

Glen

---

Original Message -----

From: David Loveless nrc.gov

Sent: Wednesday, March 03, 2004 2:21 PM To: Seeman, Glen A.

Cc: Sutton, Kent E.

Subject:

Service Water Modeling Glen, It is my understanding that should normal service water need to be isolated from the Class portion of the Divisions, it is done by closing MOVs 36 and 37, thus separating the Divisions also. For some reason, the simplified drawing that was provided to INEEL showed the isolation by an MOV-1 17 on the nonclass portion of the piping. Could you verify which is correct?

Additionally, I need to know the nonclass isolation signals and what the system success criteria would be if the nonclass piping did not isolate as designed.

Thanks for your assistance and patience as we update our model. I believe that it will be in all our best interests to have a valid SPAR.

Thanks, David CC: "Sutton, Kent E." <kesutto@nppd.com>

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