AEP-NRC-2013-85, Response to Request for Additional Information Regarding the Emergency License Amendment Request Regarding Containment Distributed Ignition System
| ML13284A074 | |
| Person / Time | |
|---|---|
| Site: | Cook  |
| Issue date: | 10/08/2013 |
| From: | Gebbie J Indiana Michigan Power Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| AEP-NRC-2013-85 | |
| Download: ML13284A074 (10) | |
Text
INDIANA Indiana Michigan Power MICHIGAN Cook Nuclear Plant POWERO One Cook Place Bridgman, MI 49106 A unit of American Electric Power IndianaMichiganPower.com AEP-NRC-2013-85 October 8, 2013 10 CFR 50.90 Docket No.: 50-315 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC, 20555-0001 Donald C. Cook Nuclear Plant Unit 1 Response to Request for Additional Information Regarding the Emergency License Amendment Request Regarding Containment Distributed Ignition System
References:
- 1. Letter from Joel P. Gebbie, Indiana Michigan Power Company (I&M), to U. S. Nuclear Regulatory Commission (NRC) Document Control Desk, "Donald C. Cook Nuclear Plant Unit 1 Emergency License Amendment Request Regarding Containment Distributed Ignition System," dated October 7, 2013.
- 2. Electronic mail from Thomas J. Wengert, NRC, to Helen L. Etheridge, I&M, "DC Cook Emergency LAR Draft RAI Revision 1," dated October 8, 2013.
This letter provides Indiana Michigan Power Company (I&M), licensee for Donald C. Cook Nuclear Plant (CNP) Unit 1, response to the Request for Additional Information (RAI) from the U. S. Nuclear Regulatory Commission (NRC) for the Emergency License Amendment Request (LAR) regarding Containment Distributed Ignition System.
By Reference 1, I&M proposed to amend CNP Unit 1 Facility Operating License DRP-58 to modify Technical Specification (TS) 3.6.9, "Distributed Ignition System (DIS)." By Reference 2, the NRC transmitted an RAI regarding the Emergency LAR submitted by I&M in Reference 1.
Enclosure 1 to this letter provides an affirmation statement pertaining to the information contained herein. Enclosure 2 provides I&M's response to the RAI. Enclosure 3 to this letter provides revised Unit 1 TS pages marked to show the proposed changes. New clean Unit 1 TS pages with proposed changes incorporated will be provided to the NRC Licensing Project Manager when requested.
Associated TS Bases changes will be made in accordance with the CNP Bases Control Program.
,4oo(
U. S. Nuclear Regulatory Commission AEP-NRC-2013-85 Page 2 Copies of this letter and its enclosures are being transmitted to the Michigan Public Service Commission and Michigan Department of Environmental Quality, in accordance with the requirements of 10 CFR 50.91.
There are no new regulatory commitments made in this letter. Should you have any questions, please contact Mr. Michael K. Scarpello, Regulatory Affairs Manager, at (269) 466-2649.
Sincerely, Joel P. Gebbie Site Vice President HLE/dmb
Enclosures:
- 1. Affirmation
- 2. Response to Request for Additional Information Regarding the Emergency License Amendment Request Regarding Containment Distributed Ignition System
- 3. Revised Donald C. Cook Nuclear Plant Unit 1 Technical Specification Pages Marked To Show Proposed Changes c: J.T. King - MPSC S. M. Krawec, AEP Ft. Wayne, w/o enclosures MDEQ - RMD/RPS NRC Resident Inspector C. D. Pederson - NRC Region III T. J. Wengert - NRC Washington DC
Enclosure I to AEP-NRC-2013-85 AFFIRMATION I, Joel P. Gebbie, being duly sworn', state that I am Site Vice President of Indiana Michigan Power Company (I&M), that I am authorized to sign and file this request with the Nuclear Regulatory Commission on behalf of I&M, and that the statements made and the matters set forth herein pertaining to I&M are true and correct to the best of my knowledge, information, and belief.
Indiana Michigan Power Company Joel P. Gebbie Site Vice President SWORN TO AND SUBSCRIBED BEFORE ME THIS -) DAY OF 22013 N-taryDANIELLE BUG2 Public StB OYNE 0 hx My CornPbty of j OIchiga Nofg Public ImtIrs~g n h On Xires erLt04.n a My Commission Expires _________
Enclosure 2 to AEP-NRC-2013-85 Response to Request for Additional Information Regarding the Emergency License Amendment Request Regarding Containment Distributed Ignition System Documents referenced in this enclosure are identified at the end of this enclosure.
By letter dated October 7, 2013 (Reference 1), Indiana Michigan Power Company (I&M), the licensee for Donald C. Cook Nuclear Plant (CNP) Unit 1, proposed to amend CNP Unit 1 Facility Operating License DRP-58 to modify Technical Specification (TS) 3.6.9, "Distributed Ignition System (DIS)." The requested change to TS 3.6.9 would allow continued operation in Mode 1 with the three inoperable hydrogen ignitors. Surveillance data obtained on October 4, 2013, indicated that three hydrogen ignitors are inoperable. Two of the inoperable ignitors are on Train B, thereby rendering Train B inoperable. One of the inoperable ignitors is on Train A in the same lower containment Phase (Phase 3) as the Train B ignitors, thereby indicating that one containment region may have no operable hydrogen ignitors. The proposed TS modification would have two separate changes. One would be to allow Train B of the DIS to be considered operable with 2 ignitors inoperable. The other would be to allow all of containment regions for the lower containment Train A and Train B Phase 3 ignitors to be considered operable. These changes would be based on the Train A and Train B Phase 3 ignitors to remain capable of performing their safety function. The proposed TS modification would be applicable until the Fall 2014 refueling outage, or until the unit enters Mode 3 which allows replacement of the affected ignitors without exposing personnel to significant radiation and safety hazards. By electronic mail dated October 8, 2013 (Reference 2), the U. S. Nuclear Regulatory Commission transmitted a Request for Additional Information (RAI) regarding the Emergency License Amendment Request submitted by I&M in Reference 1.
The following is a restatement of each RAI followed by I&M's response to each RAI
RAI 1
Section 3.3 states that a modification is to be installedduring the next refueling outage in Fall 2014. When was this modification initiated? When was it initially scheduled for installation?Was it ever deferred from a previous outage?
Response to RAI I In November 2012, as a result of a corrective action evaluation for a failed DIS ignitor, the modification was identified as a corrective action to improve the long-term reliability of the DIS ignitors. The modification was initially scheduled to be installed during the Unit 1 Cycle 26 refueling outage which is scheduled for the Fall of 2014. The Unit 1 Cycle 25 refueling outage occurred in the Spring of 2013 which did not allow sufficient time for the modification to be developed, planned, and installed during that outage. Therefore this modification has not been previously deferred from an outage
RAI 2
Section 3.2 second paragraph states "Radiation and high temperature hazards precluded access that would allow visual observation or repairof all Train A and Train B to AEP-NRC-2013-85 Page 2 lower igniters in strings powered by Phase 3, except for Train A Phase 3 igniter A35."
Citing this exception for igniterA35, could it be energized and a containment entry made to observe it for the "glow"and perhaps determine if it is the inoperable A train phase 3 igniter which would verify that Regions 12, 13, 14, 15 & 16 have at least one operable igniterthus determining if Condition B is actually met?
Response to RAI 2 Train A DIS is currently considered "guarded equipment" due to Train B DIS being inoperable.
Any action that could potentially affect the operability of Train A is restricted in order to preclude entry into TS 3.0.3. Should Train A DIS be rendered inoperable for any reason during testing or maintenance, both trains of DIS would then be inoperable requiring entry into TS 3.0.3 and subsequent shutdown of Unit 1 to Mode 3 within 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br />. Additionally, it is noted that Unit 2 is currently shutdown for refueling with significant switchyard work occurring as a part of planned maintenance. These activities increase the risk associated with a Unit 1 shutdown.
RAI 3
The LAR states: "The proposed TS change, which would allow Unit 1 to remain in Mode I until the affected ignitors can be replaced during an outage that occurs for other reasons, is preferable to the transient that would be incurred if the unit were forced to shut down."
Explain what TS Mode is required to perform the repair/replacementof the affected ignitors without exposing personnel to significant radiationand safety hazards.
Response to RAI 3 A review of the temperature and radiation hazard exposure to personnel was done using different scenarios of 100 percent (%) power, 25% power, and Mode 3. This review determined that Mode 3 or lower was required to be able to access all of the ignitors in Phase 3 of Train A and Train B. Footnote 1 and Footnote 2 on both TS pages have been revised to state "Mode 3 or lower." The revised marked up TS pages are in Enclosure 3 of this letter.
RAI 4
The LAR states: "The proposed TS change, which would allow Unit 1 to remain in Mode 1 until the affected ignitors can be replaced during an outage that occurs for other reasons, is preferable to the transient that would be incurred if the unit were forced to shut down.
If the plant is in Mode 3 for any reason before the end of fuel cycle 25, explain why the plant cannot be placed in the Mode identified in your response to RAI #3 to facilitate replacement of the failed ignitorspriorto returning to power operation.
Response to RAI 4 See the response above to RAI 3.
to AEP-NRC-2013-85 Page 3
RAI 5
10 CFR 50.36(c)(3) States: "Surveillance requirements. Surveillance requirements are requirements relating to test, calibration, or inspection to assure that the necessary quality of systems and components is maintained, that facility operation will be within safety limits, and that the limiting conditionsfor operation will be met."
The proposed Technical Specification changes would allow a relaxation of the performance TS 3.6.9, Condition A, Required Action A.2 Completion Time from performance of SR 3.6.9.1 from once per 7-days to the SR Frequency of 184 days.
Given the stated suspected ignitor failure mechanism (operation at excessive voltage) and the method of discovery (TS Surveillance testing), explain how the relaxation of testing of the Operable DIS Train provides assurancethat the LCO is met.
Response to RAI 5 The ignitors are tested four times during each operating cycle to satisfy the TS Surveillance Requirements (SR). The preventative maintenance replacement frequency is once every 3 refueling cycles. The ignitors currently installed in Unit 1 lower containment were most recently replaced during the Unit 1 Cycle 24 Fall 2011 refueling outage. With the cycling of the ignitors being the primary degradation mechanism, surveillance testing completed for Unit 1 DIS to date has consumed roughly half of the ignitor life expectancy. Additional testing would have the effect of accelerating the approach of these ignitors to their end of life. To provide assurance that the LCO continues to be met and without reducing their life expectancy, a Footnote 3 has been added to the TS SR for the Frequency of SR 3.6.9.1 and SR 3.6.9.2 to the Frequency of 184 days, such that testing Train A and Train B occurs on a staggered basis every 92 days until the next entry into Mode 3 which allows replacement of the affected ignitors. The first such staggered test will be conducted starting 92 days from the most recent surveillance on October 4, 2013. The revised marked up TS pages are in Enclosure 3 of this letter.
RAI 6
Footnote 2 on proposed TS page 3.6.9-2 appears to be incomplete (Regions 15 and 16 are not addressed). Confirm.
Response to RAI 6 I&M confirms that Footnote 2 on proposed TS Page 3.6.9-2 is incomplete. Regions 15 and 16 have been added to the proposed TS Page 3.6.9-2. The revised marked up TS pages are in of this letter.
References
- 1. Letter from Joel P. Gebbie, Indiana Michigan Power Company (I&M), to U. S. Nuclear Regulatory Commission (NRC) Document Control Desk, "Donald C. Cook Nuclear Plant Unit 1 Emergency License Amendment Request Regarding Containment Distributed Ignition System," dated October 7, 2013.
to AEP-NRC-2013-85 Page 4
- 2. Electronic mail from Thomas J. Wengert, NRC, to Helen L. Etheridge, I&M, "DC Cook Emergency LAR Draft RAI Revision 1," dated October 8, 2013.
Enclosure 3 to AEP-NRC-2013-85 REVISED DONALD C. COOK NUCLEAR PLANT UNIT 1 TECHNICAL SPECIFICATION PAGES MARKED TO SHOW CHANGES 3.6.9-1 3.6.9-2
DIS 3.6.9 3.6 CONTAINMENT SYSTEMS 3.6.9 Distributed Ignition System (DIS)
LCO 3.6.9 Two DIS trains shall be OPERABLE. I(See footnote 1 AND Each containment region shall have at least one OPERABLE hydrogen ignitor. I(See footnote 2)1 APPLICABILITY: MODES 1 and 2.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. One DIS train A.1 Restore DIS train to 7 days inoperable. Se OPERABLE status.
footnote 1)
OR A.2 Perform SR 3.6.9.1 on the Once per 7 days OPERABLE train.
B. One containment region B.1 Restore one hydrogen 7 days with no OPERABLE ignitor in the affected hydrogen ignitor. F containment region to
ýfootnote 2) OPERABLE status.
C. Required Action and C.1 Be in MODE 3. 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> associated Completion Time not met.
Footnote 1: For the remainder of Fuel Cycle 25, or until the next entry into MODE 3 or lower which allows replacement of the affected ignitors, DIS Train B may be considered OPERABLE with two lower containment Phase 3 Power Supply ignitors inoperable.
Footnote 2: For the remainder of Fuel Cycle 25, or until the next entry into MODE 3 or lower which allows replacement of the affected ignitors, one of the following regions is allowed to have no OPERABLE ignitor: Region 12, 13, 14, 15, or 16.
Cook Nuclear Plant Unit 1 3.6.9-1 Amendment No. 287
SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.9.1 Energize each DIS train power supply breaker and 184 days Se verify > 34 ignitors Ior - 33 ignitors if allowed b ootnote 3) ootnote 1 are energized in each train.
SR 3.6.9.2 Verify at least one hydrogen ignitor is OPERABLE in 184 days Se each containment region. F(See footnote 2otnote SR 3.6.9.3 Energize each hydrogen ignitor and verify 24 months temperature is > 17000 F. I(See footnote 1)1 Footnote 1: For the remainder of Fuel Cycle 25, or until the next entry into MODE 3 or lower which allows replacement of the affected ignitors, DIS Train B may be considered OPERABLE with two lower containment Phase 3 Power Supply ignitors inoperable.
Footnote 2: For the remainder of Fuel Cycle 25, or until the next entry into MODE 3 or lower which allows replacement of the affected ignitors, one of the following regions is allowed to have no OPERABLE ignitor: Region 12, 13, 14, 15 or 16.
Footnote 3: For the remainder of Fuel Cycle 25, or until the next entry into MODE 3 or lower which allows replacement of the affected ignitors, DIS Train A and Train B will be tested on a staggered basis, such that one Train is tested every 92 days starting with the first staggered test to be performed 92 days after the surveillance performed on October 4, 2013.
Cook Nuclear Plant Unit 1 3.6.9-2 Amendment No. 287