ML121710592

Email, Request for Additional Information, Round 2, License Amendment Request for Proposed Change to Technical Specification 3/4.7.4 Table 3.7-3, Ultimate Heat Sink Minimum Fan Requirements Per Train

ML121710592
Person / Time
Site:	Waterford
Issue date:	06/19/2012
From:	Kalyanam N Plant Licensing Branch IV
To:	Mason M, Joseph E Pollock Entergy Operations
Kalyanam N, NRR/DORL, 415-1480
References
TAC ME7342
Download: ML121710592 (1)

Text

From:

Kalyanam, Kaly Sent:

Tuesday, June 19, 2012 3:36 PM To:

MASON, MICHAEL E (WF3); POLLOCK, JIM

Subject:

RAI on UHS LAR

Mike, By letter dated October 13, 2011, as supplemented by letters dated November 25, 2011, and January 18 and April 3, 2012, Entergy Operations, Inc. (Entergy) made application to amend the Technical Specifications (TS) 3/4.7.4 Table 3.7-3, "Ultimate Heat Sink Minimum Fan Requirements Per Train." of the Waterford Steam Electric Station, Unit 3 (Waterford 3).

Since the 1-year metrics is approaching, the staff requests you to provide a response to the RAI below as soon as possible but within 30 days from the date of this email. This date was discussed with you on June 19, 2012.

Thanks Kaly N, Kalyanam PM, Waterford 3 and ANO 1 & 2 NRR/DORL/LPL4 REQUEST FOR ADDITIONAL INFORMATION WATERFORD STEAM ELECTRIC STATION, UNIT 3 LICENSE AMENDMENT REQUEST TO REVISE TECHNICAL SPECIFICATION 3/4.7.4 TABLE 3.7-3, ULTIMATE HEAT SINK MINIMUM FAN REQUIREMENTS PER TRAIN, DOCKET NO. 50-382

RAI-1

Background The licensee has performed Calculation ECM95-008,Ultimate Heat Sink Design Basis, to determine the Ultimate Heat Sink (UHS) design basis under LOCA conditions using the worst combination meteorological design parameters and to account for the impact of the replacement steam generators. When describing the heat transfer associated with the wet cooling towers, QWCT, the licensee used the relationship: QWCT =mCP (T), where m is the mass flow rate of water, CP is the specific heat and, and T is the cooling range.

Issue This equation does not account for the evaporative cooling effect of a wet cooling tower which is normally expressed in terms of a change in enthalpy. Thus the calculated temperature of the water out of the cooling tower basin is affected, which affects the UHS design wet cooling tower (WCT) cooling range, the component cooling water (CCW) heat exchanger fouling factor and the graph shown in attachment 7.3 of the base calculation, among possible other effects.

Request Please explain your use of the above described equation for the WCTs in calculation ECM95-008. What changes, if any, are necessary to calculation ECM95-008 and TS 3/4.7.4.

RAI-2

Background In establishing the UHS design basis in Calculation ECM95-008,Ultimate Heat Sink Design Basis, the licensee has assumed 100% tube capacity on the DCT and 95% tube capacity on the CCW heat exchanger and has used the manufacturers performance curves for the DCT and WCT. The calculations intent is to show that the dry cooling tower (DCT) with 15 fans and the WCT with 8 fans meets the LOCA heat removal requirements using the worst combination meteorological design parameters.

Issue Tube fouling and wet cooling tower fill fouling can adversely affect the heat transfer capabilities of the DCT, WCT and CCW heat exchanger and thus adversely affect the assumptions and performance curves described above.

Request Identify and describe the testing and maintenance that is performed on the DCT, WCT and CCW heat exchanger that verifies that these components are functioning as described in the design basis calculation ECM95-008.