RNP-RA/14-0037, Response to NRC Request for Additional Information Regarding License Amendment Request to Modify Technical Specification 3.4.12, Low Temperature Overpressure Protection System

Response to NRC Request for Additional Information Regarding License Amendment Request to Modify Technical Specification 3.4.12, Low Temperature Overpressure Protection System

ML14106A370
Person / Time
Site:	Robinson
Issue date:	04/08/2014
From:	William Gideon Duke Energy Corp, Progress Energy Carolinas
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
RNP-RA/14-0037
Download: ML14106A370 (6)

Text

W A 0Moo H.8Rob*Wo Siftm c

s8l.t ntJ W 2 DUKE Ste VVe Pms.wx 351" ~m Enhno. Ao H&12v**. SC 2960 F 843 W 1319 10 CFR 50.90 Serial: RNP-FWAt4-0037 APR 0 8 2014 AITN: Documert Contro Desk U.S. Nuclear Regulatory Commission Washington. DC 20558 K&.8. ROBINSON STEAM ELECTRIC PLANT, UNIT NO. 2 DOCKET NO 50-261/RENEWED LICENSE NO. OPR-23

& W: Response tolORC ReqsM, for Addidona tAxmuttsn RfyoIdbwUs Amn Reques ft T irdncaI 1p3 flvatlon 3.I "T) Low erlatwe Ow rees~uws ftocon (LTOP) System Refemnoe:

1. NRC Ekletronic Mail, Requests for Additional Infomwiston (RAI*) for License mendnment Re*s to M6fy TS 3.4.12, Low Temperstur Overpressur Protection System; dated March 10, 2014, (Agencywid. Documeft Access and Managent System (ADAMS)

Accession No. ML14069A387).

2. LUA* Amendmn"RpquWto Modify T*chical Specification (TS) 3.4.12, Low,,

Temperature Overpressure Protectkon (LTOP) System, dated September 10, 2013

-(j$DAMS Accession No. ML13262A008).

Ladles mnd Gentlenmn:

By letter (Reference 2) to the U.S. Nucer Regulatory Comission (NRC) dated September 10, 2013, (ADAMS Accession No. ML13262A008), Duke Energy submitted a license amendment request (LAR) for H. S. Robinson Steam Electric Plant (HBRSEP), Unit No. 2. The proposed LAR would modify Techial Specification (TS) Surveillance Requirement 3.4.12.6 of TS 3.4.12, Low Temperature Overpressau Protection (LTOP) System with a Note that does not require that the surveillance be performed until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after decreasing the reactor coolant system cold leg temperature to less than or equal to 350°F, which is the temperature when LTOP operability controlled by TS 3.4 12 is credited. In addition, the FREQUENCY requirement is modified to siml 31 days.

By electronic mail transmission dated March 10, 2014, (ADAMS Accession No. 14069A387)

(Reference 1) the NRC staff requested additional InIfmaon needed to contiWue Its review of Duke Eriergij response to*ThJquelfor a~dditlpl infrmation is provided in the enclosure to this lt~e.

45(2 A00

- -'LCb;

U.S. Nuclear Re*gatory Commisson Serial: RNPA14-O037 Page 2 of 2 This letter contains no new Regulatory Commitments and no revision to existing Regulatory Commitments.

Should you have any questions regarding this submittK please contact Mr. Richard Hightower, Manager, Nuclear Regulaory Affairs at (843) 857-1329.

I declare undler penalty of perjury that the foregoing Is true and correct.

Executed on A,-, 2-0 .

Sincerely, 6 44, eCILA.ý 4L_

W. FR Gideon Site Vice President WRGQJmw

Enclosure:

H. B. Robinson Steam Electric Plant, Unit No. 2 Response to the NRC Request for Additional information (RAI) Regarding License Amenrdent Request to Modify TS 3.4.12, Low Temperature Overpressure Protection System cc: Mr. K. M. Ellis, NRC Senior Resident Inspector Mr. S. P. LUngam, NRC Project Manager, NRR Mr. V. M. McCree, NRC Region IIAdministrator

U. S. Nuclear Regulatory Commission Enclosure to Serial: RNP-RA/14-0037 Page 1 of 4 Enclosure H. B. Robinson Steam Electric Plant, Unit No. 2 Response to the NRC Request for Additional Information (RAI)

Regarding License Amendment Request to Modify TS 3.4.12, Low Temperature Overpressure Protection System

U. S. Nuclear Regulatory Commission Enclosure to Serial: RNP-RA/14-0037 Page 2 of 4 NRC REQUEST FOR ADDITIONAL INFORMATION (RAI)

By letter dated September 10, 2013, Duke Energy Progress, Inc., the licensee, submitted a license amendment request (LAR). The proposed amendment would modify Technical Specification (TS) Surveillance Requirement (SR) 3.4.12.6 of TS 3.4.12, Low Temperature Overpressure Protection (LTOP) System, with a Note that does not require that the surveillance be performed until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after decreasing the reactor coolant system (RCS) cold leg temperature to less than or equal to 350 OF. In addition, the FREQUENCY requirement would be modified to simply 31 days.

Based on the its review of the amendment request, the Nuclear Regulatory Commission (NRC) staff has determined that additional information is required regarding the Note to TS SR 3.4.12.6 and FREQUENCY modifications.

SRXB - RAI 1 Please provide justification for adoption of NUREG-1431, Revision 3, "Standard Technical Specifications Westinghouse Plants," for TS SR 3.4.12.6 of TS 3.4.12, LTOP System. Please also provide a safety basis for the modification. This basis may include procedural controls, operator training, and related considerations. The basis may also include similar considerations that show that the consequences of such a simultaneous actuation are reasonably mitigated.

SRXB - RAI 2 In the LAR, it is stated that there is a low probability for a low temperature overpressure event within this limited time period. The NRC staff notes that the LTOP will be armed for up to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> in MODE 4, without a surveillance requirement verifying the operability of the power-operated relief valves (PORVs) instrumentation. Please provide additional detail about the low probability of a low temperature overpressure event occurrences by describing plant operational experience with LTOP events. How many LTOP events have occurred, and if any have occurred, have they occurred within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> of entry into MODE 4?

SRXB - RAI 3 TS SR 3.4.12.6 is for the channel operational test to verify the PORV lift setpoint is within the maximum limits in the LTOP analyses and, as necessary, adjust the lift setpoint. Please provide any missed or failed surveillances related to TS SR 3.4.12.6.

U. S. Nuclear Regulatory Commission Enclosure to Serial: RNP-RA/1 4-0037 Page 3 of 4 Duke Energy Response to SRXB - RAI 1:

Surveillance Requirement (SR) 3.4.12.8 of the ISTS includes a Note that allows the completion of the performance of the Channel Operational Test (COT) for each required PORV to be delayed until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after entering into the applicable MODE in which the PORVs are required to provide Low Temperature Overpressure Protection (LTOP). The purpose of this Note is to provide time to establish the conditions necessary to perform the SR since at some plants the required COT cannot be performed until the plant is in the LTOP MODES.

HBRSEP Unit No. 2 Improved Technical Specifications (ITS) 3.4.12 is modified to delete this Note because the design of the LTOP System at HBRSEP Unit No. 2 is such that this SR can be performed prior to entering the LTOP MODES. However, it has been observed that although the SR can be performed prior to entering the LTOP MODES, in a TS-related rapid shutdown situation this requirement could unnecessarily delay transition from MODE 3 to MODE 4 due to the limited time frame creating inadequate resources for completion of the SR. To the end of reducing the possibility of such a delay during a TS-related rapid shutdown situation, HBRSEP Unit No. 2 desires to perform this SR subsequent to the plant entering the LTOP MODES.

The safety basis for the change to SR 3.4.12.8 consists of performing a COT of TS SR 3.4.12.6 via Maintenance Surveillance Test (MST)-007 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after decreasing RCS temperature to <350°F (LTOP arming temperature) and every 31 days on each required PORV to verify and, as necessary, adjust its lift setpoint. A successful test of the required contact(s) of a channel relay may be performed by the verification of the change of state of a single contact of the relay. This clarifies what is an acceptable COT of a relay. This is acceptable because all of the other required contacts of the relay are verified by other TS and non-TS tests at least once per refueling interval with applicable extensions. The COT will verify the setpoint is within the Pressure Temperature Limit Report (PTLR) allowed maximum limits in the PTLR. For HBRSEP, Unit No. 2, CHANNEL CALIBRATION per TS SR 3.4.12.7 in Loop Calibration Procedure (LP)-039, LP-004, Process Instrument Calibration Procedure (PIC)-006 and Engineering Surveillance Test (EST)-052 are performed at 18-month intervals and are in frequency during refueling outages.

Duke Energy Response to SRXB - RAI 2:

The following four (4) LTOP events have occurred at HBRSEP2.

" On November 2, 1993, PZR Power Operated Relief Valve PCV-456 actuated twice to relieve pressure when a Reactor Coolant Pump was started and Low Pressure Letdown Pressure Control Valve PCV-145 did not respond as expected to the pressure transient.

Adverse Condition Report (ACR)93-254). This event occurred coming out of an outage, not within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> of entry into MODE 4. (RNP/94-0449)

• On March 30, 1987, PCV-456 opened to relieve a Reactor Cool pressure transient caused by a malfunction of the "B" charging pump. (RNP/88-0620)(RNPD/87-1670)

This event did not occur within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> of entry into MODE 4.

U. S. Nuclear Regulatory Commission Enclosure to Serial: RNP-RA/14-0037 Page 4 of 4 On October 16, 1989, PCV-456 opened to relieve a RCS pressure transient when RHR-759B was closed. Closure of RHR HX "B" Discharge valve RHR-759B isolated the RHR letdown line and PCV-145. (RNPD/89-3661)(RNPD/90-0683) This event did not occur within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> of entry into MODE 4.

Duke Energy Response to SRXB - RAI 2:

Maintenance Surveillance Test, MST-007 performs SR 3.4.12.6. A current and historical Corrective Action Program (CAP) search was performed for Nuclear Condition Reports (NCRs) written on missed or failed surveillance tests; no such NCRs were revealed.