NLS2015030, Response to Nuclear Regulatory Commission Requests for Additional Information for License Amendment Request to Delete Condensate Storage Tank as an Alternate Source of Make-Up Water
| ML15062A037 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 02/25/2015 |
| From: | Limpias O Nebraska Public Power District (NPPD) |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NLS2015030, TAC MF4716 | |
| Download: ML15062A037 (4) | |
Text
H Nebraska Public Power District Always there when you need us NLS2015030 February 25, 2015 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001
Subject:
Response to Nuclear Regulatory Commission Requests for Additional Information for License Amendment Request to Delete Condensate Storage Tank as an Alternate Source of Make-Up Water (TAC No. MF4716)
Cooper Nuclear Station, Docket No. 50-298, DPR-46
References:
- 1.
Email from Siva Lingam, U.S. Nuclear Regulatory Commission, to Jim Shaw, Nebraska Public Power District, dated January 29, 2015, "Cooper Nuclear Station - Requests for Additional Information (RAIs) for License Amendment Request to Delete Condensate Storage Tank as an Alternate Source of Make-Up Water (TAC No. MF4716)"
- 2.
Letter from Oscar A. Limpias, Nebraska Public Power District, to the U.S.
Nuclear Regulatory Commission, dated August 26, 2014, "License Amendment Request to Delete Condensate Storage Tank as an Alternate Source of Makeup Water"
Dear Sir or Madam:
The purpose of this letter is for the Nebraska Public Power District to respond to the Nuclear Regulatory Commission's Request for Additional Information (RAI) (Reference 1) related to the Cooper Nuclear Station License Amendment Request to Delete Condensate Storage Tank as an Alternate Source of Makeup Water (Reference 2).
The responses to the specific RAI questions are provided in the attachment to this letter.
This letter does not contain any new regulatory commitments.
If you have any questions concerning this matter, please contact Jim Shaw, Licensing Manager, at (402) 825-2788.
COOPER NUCLEAR STATION A C -
P.O. Box 98 / Brownville, NE 68321-0098 Telephone: (402) 825-3811 / Fax: (402) 825-5211 www.nppd.com
NLS2015030 Page 2 of 2 I declare under penalty of perjury that the foregoing is true and correct.
Executed on:
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(Date)
SincereP Oscar Limpias Vice President - Nuclear and Chief Nuclear Officer Jo Attachments: Response to Nuclear Regulatory Commission Requests for Additional Information for License Amendment Request to Delete Condensate Storage Tank as an Alternate Source of Make-Up Water cc:
Regional Administrator w/ attachments USNRC - Region IV Cooper Project Manager w/ attachments USNRC - NRR Project Directorate IV-1 Senior Resident Inspector w/ attachments USNRC - CNS NPG Distribution w/o attachments CNS Records w/ attachments
NLS2015030 Attachment Page 1 of 2 Attachment Response to Nuclear Regulatory Commission Requests for Additional Information for License Amendment Request to Delete Condensate Storage Tank as an Alternate Source of Make-Up Water (TAC No. MF4716)
Cooper Nuclear Station, Docket No. 50-298, DPR-46 The Nuclear Regulatory Commission request for additional information regarding the request to delete Condensate Storage Tank as an Alternate Source of Make-Up Water is shown in italics.
The Nebraska Public Power District response to the request is shown in block font.
RAI-]
If CST 'A'is deleted as an alternate source of water, how will make up water be provided to the Reactor Pressure Vessel if the ECCS is inoperable as a result of suppression pool water level below the required limit?
NPPD Response:
With the suppression pool water level below 12 feet 7 inches, Emergency Core Cooling System (ECCS) remains available for make up water to the Reactor Pressure Vessel (RPV). Even though CST 'A' does not meet the seismic qualification, it remains available as a water source for ECCS.
The suppression pool will never be intentionally drained down below 12 feet 7 inches. In the event of inadvertent drain down below 12 feet 7 inches, Limiting Condition for Operation 3.5.2, Condition 'C' will be entered, and all operations with a potential for draining the reactor vessel (OPDRVs) must be suspended immediately along with restoration of ECCS operability within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. ECCS operability in this case is contingent upon restoring suppression pool water level above the required 12 feet 7 inches. Restoration will be accomplished via Emergency Operating Procedure 5.8.14, Suppression Pool Make Up Systems.
The Main Condensate System or Reactor Building Auxiliary Condensate Booster Pump would be used to provide make up to the suppression pool thru the High Pressure Coolant Injection minimum flow line, the Reactor Core Isolation Cooling minimum flow line, the Residual Heat Removal Suppression Pool Cooling line, or the Core Spray test line. Water sources for these injection options are the Condensate Storage Tank 'A', Condensate Storage Tank 'B',
Demineralized Water Tank, Main Condenser 'A', Main Condenser 'B'. With adequate water level restored to the suppression pool, ECCS operability is restored.
NLS2015030 Attachment Page 2 of 2
RAI-2
Provide justification for not having an alternate source of water once the suppression pool is less than the required limit, making ECCS inoperable.
NPPD Response:
The Outage Shutdown Safety procedure provides restrictions for OPDRV evolutions. OPDRVs are limited by the unprotected hole size in such a way that 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of drain time is assured from nominal refuel level to RPV flange.
In the unlikely, unintentional event an OPDRV condition existed simultaneously with ECCS inoperability as a result of low suppression pool water level, 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br /> of margin is assured by the restrictions of the procedure. ECCS operability will be restored long before water level in the RPV reaches the RPV flange.