ML111120260

EPU - Request for Additional Information (PRA Licensing)

ML111120260
Person / Time
Site:	Saint Lucie
Issue date:	04/22/2011
From:	Orf T Plant Licensing Branch II
To:	Wasik C Florida Power & Light Co
Orf, T J, NRR/DORL/301-415-2788
References
Download: ML111120260 (2)

Text

From: Orf, Tracy Sent: Friday, April 22, 2011 1:14 PM To: 'Wasik, Chris'

Subject:

St. Lucie Unit 1 EPU - request for additional information (PRA Licensing)

Dear Mr. Wasik,

By letter dated November 22, 2010 (Agencywide Documents Access and Management System Accession No. ML103560415) Florida Power & Light Company (the licensee) submitted a license amendment request for St. Lucie Unit 1.

The U.S. Nuclear Regulatory Commission (NRC) staff has reviewed the licensee's submittal and has concluded that additional information is required from the licensee in order for the NRC staff to complete their review. The questions below describe these requests for additional information (RAls).

The NRC requests that the licensee respond to these RAls within 30 days of the date of this e-mail. If the licensee concludes that more than 30 days are required to respond to the RAls, the licensee should request additional time, including a basis for why the extension is needed.

Please contact me at the number below or by e-mail if you have any questions on this issue or if you require additional time to submit your responses.

Sincerely, Tracy J. Orf, Project Manager St. Lucie Plant Licensing Branch II-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Phone: (301) 415-2788 REQUEST FOR ADDITIONAL INFORMATION (RAI)

REGARDING LICENSE AMENDMENT REQUEST FOR EXTENDED POWER UPRATE ST. LUCIE PLANT, UNIT NO.1 DOCKET NO. 50-335 APLA-1: Section 2.13.2.5 of Attachment 5 states the following on shutdown operations risk:

With the exception of EPUs impact on time available for operator actions, no further impact of EPU is expectedReductions in available times for operators to

take compensatory or mitigating actions could vary from several to ten or more minutes, dependent on shutdown conditions. The safety evaluation demonstrates that the shorter available time window under EPU would not adversely impact safety consequences.

Provide additional information for how the safety evaluation demonstrates that shorter available time windows under the EPU would not impact safety consequences. Specifically, address how the EPU impacts the ability of the operator to close containment and provide additional information regarding the reliability and availability of equipment used for shutdown conditions. In addition, explain the impact of the EPU on alternate decay heat removal systems.

APLA-2: Section 2.13.2.6.1.4 of Attachment 5 states the following on pressurizer level control program:

The pressurizer level control program will change for EPU. Currently, the pressurizer level varies from 33.09% at 15% power to 65.6% at 100% power.

After EPU, the pressurizer level will be 33.09% at 15% power, reach 65.6% at approximately 90% power and maintain that level through 100% power.

With a ten percent power uprate, one hundred percent power at pre-EPU conditions corresponds to approximately ninety percent power at EPU conditions; the pressurizer level remains constant at 65.6% at both of these conditions.

Fifteen percent power at pre-EPU conditions approximately corresponds to 13.5% power at EPU conditions. Please explain why a ten percent power increase keeps the lower limit constant at 33.09% pressurizer level at 15% power for both pre-EPU and EPU conditions.