AEP-NRC-2013-84, Emergency License Amendment Request Regarding Containment Distributed Ignition System

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Emergency License Amendment Request Regarding Containment Distributed Ignition System
ML13283A084
Person / Time
Site: Cook American Electric Power icon.png
Issue date: 10/07/2013
From: Gebbie J
Indiana Michigan Power Co
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
AEP-NRC-2013-84
Download: ML13283A084 (25)
v • d • e


Text

INDIANA Indiana Michigan Power MICHIGAN Cook Nuclear Plant POWER8 One Cook Place Bridlgman, MVI49106 A unit ofAmerican Electric Power India naMichiga nPower.com AEP-NRC-2013-84 October 7, 2013 10 CFR 50.90 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

SUBJECT:

Donald C. Cook Nuclear Plant Unit 1 Docket No. 50-315 Emergency License Amendment Request Regarding Containment Distributed Ignition System

Dear Sir or Madam:

Pursuant to 10 CFR 50.90, Indiana Michigan Power Company (I&M), the licensee for Donald C. Cook Nuclear Plant (CNP) Unit 1, proposes to amend the Appendix A Technical Specifications (TS) to Facility Operating License DPR-58. I&M proposes to modify the TS for the Distributed Ignition System (DIS). The DIS is designed to initiate controlled ignition of hydrogen resulting from a postulated accident via a system of 70 ignitors (two trains of 35 ignitors) located inside containment. The existing TS requires that at least 34 ignitors per train be operable to consider the train operable and that each containment region has at least one operable hydrogen ignitor. Recent surveillance data indicates 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 Phase (Phase 3) as the Train B ignitors, thereby indicating that one containment region may have no operable hydrogen ignitors. Consequently, I&M is required to restore one hydrogen ignitor to operable in the affected containment region within 7 days or be in Mode 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> at the completion of the 7-day period, which expires on October 11, 2013, at 0446 hours0.00516 days <br />0.124 hours <br />7.374339e-4 weeks <br />1.69703e-4 months <br />. To restore the hydrogen ignitors that are inoperable, in the affected containment region, to operable requires replacement of the one Train A inoperable ignitor or the two Train B inoperable ignitors. However, it may not be possible to repair or replace any ignitors in any of the 5 potentially affected containment regions with the unit in Mode 1 because of significant radiation and safety hazards to personnel, but I&M continues to explore possible repair or replacement options.

I&M has determined that the safety function of the DIS will continue to be met even with two ignitors in one train inoperable and one containment region with no hydrogen ignitors indicated as operable.

I&M is therefore requesting a change to TS 3.6.9 that would allow continued operation in Mode 1 with the three inoperable 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 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 a mode which allows replacement of the affected ignitors without exposing personnel to significant radiation and safety hazards.

Lk W

U. S. Nuclear Regulatory Commission AEP-NRC-2013-84 Page 2 I&M is requesting that the proposed change be approved on an emergency basis in accordance with 10 CFR 50.91(5) because failure to issue the amendment in a timely manner would result in shutdown of the unit. The unit is currently operating in TS Action Requirement 3.6.9.A.1 and 3.6.9.B.1, which will require that the unit be shutdown no later than October 11, 2013. Additionally, the inoperability of Train B may result in entry into TS Limiting Condition for Operation (LCO) 3.0.3 if DIS Train A becomes inoperable or if the Train A emergency diesel generator is inoperable for more than 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. Entry into LCO 3.0.3 would require the unit to be shut down within 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br />.

This does not allow time for the 30 day public comment period specified in 10 CFR 50.91 (a)(2)(ii) prior to issuance of a normal license amendment. The ignitor failure that has resulted in the situation could not have been reasonably foreseen. Therefore, I&M could not have avoided the situation that has resulted in the need for an emergency amendment. to this letter provides an affirmation statement pertaining to the information contained herein. Enclosure 2 provides I&M's evaluation of the proposed TS change and the basis for requesting emergency approval. Enclosure 3 to this letter provides 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 Nuclear Regulatory Commission (NRC) Licensing Project Manager when requested. Associated TS Bases changes will be made in accordance with the CNP Bases Control Program.

I&M requests approval of the proposed change by October 10, 2013, which would preclude the need to shutdown the unit. The proposed change will be implemented as soon as possible, but within 1 day of NRC approval. 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/rdw

Enclosures:

1. Affirmation
2. Proposed Emergency License Amendment Request Regarding Containment Distributed Ignition System
3. Donald C. Cook Nuclear Plant Unit 1 Technical Specification Pages Marked To Show Proposed Changes

U. S. Nuclear Regulatory Commission AEP-NRC-2013-84 Page 3 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 1 to AEP-NRC-2013-84 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 *- . ,2013 DANIELLE BURGOYNE Notary Public, State of Michigan County of Berrien Nota~yI;ublick\ My Commission Expires 04-04-2018 Acting In the County of My Commission Expires C---- CN\-

Enclosure 2 to AEP-NRC-2013-84 Proposed Emergency License Amendment Request Regarding Containment Distributed Ignition System Documents referenced in this enclosure are identified in Section 8.0.

1.0 DESCRIPTION

Pursuant to 10 CFR 50.90, Indiana Michigan Power Company (I&M), the licensee for Donald C. Cook Nuclear Plant (CNP) Unit 1, proposes to amend the Appendix A Technical Specifications (TS) to Facility Operating License DPR-58. I&M proposes to modify the TS for the Distributed Ignition System (DIS). The DIS is designed to initiate controlled ignition of hydrogen resulting from a postulated accident via a system of 70 ignitors (two trains of 35 ignitors) located inside containment. The existing TS requires that at least 34 ignitors per train be operable to consider the train operable and that each containment region has at least one operable hydrogen ignitor. Recent surveillance data indicates 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 Phase (Phase 3) as the Train B ignitors, thereby indicating that one containment region may have no operable hydrogen ignitors.

Consequently, I&M is required to restore one hydrogen ignitor to operable in the affected containment region within 7 days or be in Mode 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> at the completion of the 7-day period, which expires on October 11, 2013, at 0446 hours0.00516 days <br />0.124 hours <br />7.374339e-4 weeks <br />1.69703e-4 months <br />. To restore the hydrogen ignitors that are inoperable, in the affected containment region, to operable requires replacement of the one Train A inoperable ignitor or the two Train B inoperable ignitors. However, it may not be possible to repair or replace any ignitors in any of the 5 potentially affected containment regions with the unit in Mode 1 because of significant radiation and safety hazards to personnel.

I&M has determined that the safety function of the DIS will continue to be met even with two ignitors in one train inoperable and one containment region with no hydrogen ignitors indicated as operable. I&M is therefore requesting a change to TS 3.6.9 that would allow continued operation in Mode 1 with the three inoperable 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 Train A and Train B Phase 3 ignitors to be considered operable. These changes would be based on the Train B and Train A 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 a mode which allows replacement of the affected ignitors without exposing personnel to significant radiation and safety hazards.

I&M is requesting that the proposed change be approved on an emergency basis in accordance with 10 CFR 50.91(5) because failure to issue the amendment in a timely manner would result in shutdown of the unit. The unit is currently operating in TS Action Requirement 3.6.9.A.1 and 3.6.9.B.1, which will require that the unit be shutdown no later than October 11, 2013.

Additionally, the inoperability of Train B may result in entry into TS Limiting Condition for Operation (LCO) 3.0.3 if DIS Train A becomes inoperable or if the Train A emergency diesel generator (DG) is inoperable for more than 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. Entry into LCO 3.0.3 would require the unit to be shut down within 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br />. This does not allow time for the 30 day public comment period specified in 10 CFR 50.91 (a)(2)(ii) prior to issuance of a normal license amendment. The ignitor

Enclosure 2 to AEP-NRC-2013-84 Page 2 failures that have resulted in the situation could not have been reasonably foreseen. Therefore, I&M could not have avoided the situation that has resulted in the need for an emergency amendment. The justification for requesting this approval on an emergency basis is further addressed in Section 3.5 of this enclosure.

2.0 PROPOSED CHANGE

I&M proposes to modify TS 3.6.9, "Distributed Ignition System" as follows:

Footnote 1 will be added to both pages of TS 3.6.9 as follows:

Footnote 1: For the remainder of Fuel Cycle 25, or until the next entry into a MODE which allows replacement of the affected ignitors, DIS Train B may be considered OPERABLE with two lower containment Phase 3 Power Supply ignitors inoperable.

Reference to Footnote 1 will be added to:

A parenthetical statement, "(or > 33 ignitors if allowed by footnote)," will be added to the TS 3.6.9 Surveillance Requirement 3.6.9.1 requirement to energize each DIS train and verify > 34 ignitors are energized in each train.

Footnote 2 will be added to the both pages of TS 3.6.9 as follows:

Footnote 2: For the remainder of Fuel Cycle 25, or until the next entry into a MODE 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.

Reference to Footnote 2 will be added to:

  • The TS 3.6.9 Surveillance Requirement 3.6.9.2 requirement to verify at least one hydrogen ignitor is operable in each containment region. to this letter provides Unit 1 TS pages marked to show proposed changes. New text on these pages is enclosed in a single-line border. New clean Unit 1 TS pages with proposed changes incorporated will be provided to the Nuclear Regulatory Commission (NRC)

Licensing Project Manager when requested. Associated TS Bases changes will be made in accordance with the CNP Bases Control Program.

to AEP-NRC-2013-84 Page 3

3.0 BACKGROUND

3.1 DIS Design and Operation The DIS is designed to meet 10 CFR 50.44 requirements for a system to reduce the hydrogen concentration in the primary containment following a degraded core accident. The DIS must be capable of handling an amount of hydrogen equivalent to that generated from a metal water reaction involving 75% of the fuel cladding. The DIS is designed to minimize the potential for hydrogen accumulation and preclude detonations in the unlikely event of such an accident. The DIS is based on the concept of controlled ignition using thermal ignitors, designed to be capable of functioning in a post accident environment. Analyses have shown that the deliberate ignition of hydrogen would not pose a threat to containment integrity and would not result in environmental conditions more severe than the conditions for which the majority of the necessary safety equipment has been qualified. The DIS depends on the dispersed location of the ignitors so that local pockets of hydrogen at increased concentrations would burn before reaching a hydrogen concentration significantly higher than the lower flammability limit. The Containment Air Recirculation/Hydrogen Skimmer (CEQ) system, in conjunction with upper and lower volume containment sprays, provides sufficient mixing so as to prevent the stratification or pocketing of hydrogen in the various compartments of the containment.

The DIS is a two-train system employing a total of 70 ignitor assemblies located throughout the containment building. The two trains are designated Train A and Train B. The emergency power sources for the Train A and the Train B ignitors are the Train A and Train B DGs. Each train of 35 ignitor assemblies is further divided into two groups; one group of 17 assemblies is in the general lower volume area of containment and the second group of 18 assemblies is in the general upper volume area of containment (including the ice condenser upper plenum volume).

Each ignitor assembly consists of a glow plug and a control power transformer mounted in a sealed box housing. The ignitors are supplied power in "strings." Each string consists of parallel arrangement of 4 to 7 ignitors and their associated control power transformers. Each string is powered by one phase of a three-phase power supply. Table 1 in this enclosure shows the ignitor strings grouped according to their power supply phase. The ignitors are located such that each containment region has at least two ignitors, one from each train, controlled and powered redundantly so that ignition would occur in each region even if one train failed to energize. The containment regions and their associated ignitors are listed in Table 2 in this enclosure. The containment locations of the ignitors involved in this amendment request are shown in Figure 1 in this enclosure. For Phase 3 ignitors, there is one Train A and one Train B ignitor located in each of the four SG enclosures and in the pressurizer enclosure. Each SG and pressurizer enclosure is considered a containment region as shown in Table 2, with five containment regions total for the four SG enclosures and the one pressurizer enclosure.

The DIS is a manual system controllable from the main control room or either DG room. Manual actuation of the DIS is directed by the applicable Emergency Operating Procedure. When the DIS is actuated, the ignitor elements are energized and the glow plug heats up to a surface temperature -> 1700°F. At this temperature, they would ignite hydrogen gas in the airspace in the vicinity of the ignitor.

The hydrogen ignitors are not required for mitigation of a Design Basis Accident (DBA) because an amount of hydrogen equivalent to that generated from the reaction of 75% of the fuel to AEP-NRC-2013-84 Page 4 cladding with water is far in excess of the hydrogen calculated for the limiting DBA. The hydrogen concentration resulting from a DBA can be maintained less than the flammability limit using the hydrogen recombiners.

3.2 Surveillance Testing TS Surveillance Requirement 3.6.9.1 requires that each DIS train power supply breaker be energized and requires verification that ->34 of the 35 ignitors in each train are energized. TS Surveillance Requirement 3.6.9.2 requires verifying that at least one hydrogen ignitor is operable in each containment region. The specified Frequency of both TS Surveillance Requirements 3.6.9.1 and 3.6.9.2 is 184 days. Therefore, the Surveillance Requirements are normally performed when the unit is operating in Mode 1. Many of the ignitors are not accessible with the unit operating in Mode 1 because of radiation and high temperature hazards in their containment locations, particularly in the lower containment. Therefore, current measurements, rather than direct observation, are used to verify the ignitors are energized when performing TS Surveillance Requirement 3.6.9.1 with the unit operating in Mode 1.

Radiation and high temperature hazards also preclude access to areas that would enable measurement of current to individual ignitors. Consequently, the current to each phase of the power supply, i.e., each ignitor string, is measured to ensure it is within limits established for that string. A current below the established limits indicates that one or more ignitors in that string have failed (their typical failure mechanism is to "burn out," which produces an open circuit for that ignitor). The amount by which the measured current is below the established limit will indicate the number of ignitors which have failed on that string.

When TS Surveillance Requirement 3.6.9.1 was performed on October 4, 2013, acceptable current readings were obtained for all Train A and Train B upper ignitors and all Train A and Train B lower ignitor strings powered by Phase 1 and Phase 2. However, low current readings were obtained for both Train A and Train B lower ignitor strings powered by Phase 3. The readings indicated that one ignitor in the Train A string powered by phase 3 and two ignitors in the Train B string powered by Phase 3 had failed. Radiation and high temperature hazards precluded access that would allow visual observation or repair of all Train A and Train B lower ignitors in strings powered by Phase 3, except for Train A Phase 3 ignitor A35. Therefore, two Train B ignitors (B30, B31, B32, B33, or B34) in the lower containment string powered by Phase 3 are considered to have failed, and one Train A ignitor (A30, A31, A32, A33, A34 or A35) in the lower containment string powered by Phase 3 is considered to have failed.

With two DIS Train B ignitors inoperable, the number of operable ignitors in Train B is less than the minimum of 34 ignitors required by TS Surveillance Requirement 3.6.9.1. Therefore, LCO 3.6.9 Condition A was entered. The Required Action for this Condition is to restore the inoperable DIS train to operable status within 7 days or perform TS Surveillance Requirement 3.6.9.1 on the operable DIS train at least once per 7 days. With one DIS Train A ignitor inoperable in the same Phase 3 string as the two Train B inoperable ignitors, it cannot be verified that each containment region has at least one operable hydrogen ignitor as required by TS Surveillance Requirement 3.6.9.2. Therefore, LCO 3.6.9 Condition B was entered. The Required Action for this Condition is to restore one hydrogen ignitor in the affected containment region to operable status within 7 days. At the expiration of the Condition B Completion Time of 7 days, Condition C would be entered. The Required Action for this Condition is to be in Mode 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

to AEP-NRC-2013-84 Page 5 3.3 Suspected Failure Mechanism The probable cause for the three ignitor failures identified during the October 4, 2013, surveillance testing, was determined by engineering judgment to be application of the ignitor beyond normal ratings within the DIS design. The suspected failure mode for the ignitors is due to operation of the ignitors at 14 volts AC, versus the manufacturers specification of 11.5 volts DC, resulting in decreased long-term reliability. To assure that failures do not recur, I&M plans to perform a modification to the DIS to replace the current ignitors with ignitors that are designed for the specific application and conform to DIS design required ratings. This modification is planned to be installed in Unit 1 during the next refueling outage in the Fall of 2014 with the replacement of all Unit 1 hydrogen ignitors.

3.4 Reason for Requesting Amendment As described in this section, the inoperability of DIS Train B coupled with the one inoperable Train A ignitor has several significant consequences. However, as described in Section 4.0 below, I&M has determined that DIS can continue to perform its safety function with two Train B ignitors in the lower containment string powered by Phase 3 inoperable and one Train A ignitor in the lower containment string powered by Phase 3 inoperable. Therefore, I&M is requesting NRC approval to change TS 3.6.9 to recognize that the inoperability of the three ignitors does not render DIS inoperable.

3.4.1 Required Unit Shutdown due to Two Inoperable Ignitors in One Containment Region As described above, current readings taken during surveillance testing indicate that there is one inoperable ignitor in the string powered by Train A lower containment Phase 3 and two inoperable ignitors in the string powered by Train B lower containment Phase 3. It cannot be determined which specific ignitor is inoperable in each of these strings. It must be conservatively assumed that an inoperable ignitor for each Train is located in the same region (Region 12, 13, 14, 15, or 16). Therefore, Unit 1 has entered TS LCO 3.6.9 Condition B. Since radiation and high temperature personnel hazards may preclude repairing the inoperable ignitors with the unit in Mode 1, the TS LCO 3.6.9 Condition B Required Action to restore one ignitor in the affected region to operable status within 7 days may not be met. Therefore, the LCO 3.6.9 Condition C Required Action C.1 would require that the unit be shutdown no later than October 11, 2013. However, as described in Section 4.0 below, I&M has determined that the DIS can continue to perform its safety function even if one of the potentially affected regions (Region 12, 13, 14, 15, or 16) has no operable ignitor. Therefore, I&M is requesting NRC approval to change TS 3.6.9 to recognize that the unit operation in Modes 1 and 2 may continue with two inoperable ignitors in one of these regions.

3.4.2 Potential Effect on DIS Train A Ignitors and Unit Shutdown Due to Train A Inoperability In the event that only the requested change to implement Footnote 2 is approved, I&M would still be in Condition B which would require weekly performance of TS Surveillance 3.6.9.1 to allow continued operation of the unit. If weekly performance of TS Surveillance Requirement 3.6.9.1 on DIS Train A is conducted between the current date and the planned start of the Unit 1 refueling outage in the Fall of 2014, it will result in Train A ignitors being cycled at least 52 to AEP-NRC-2013-84 Page 6 times. Performing the surveillance at this frequency could result in additional failures of ignitors in Train A as a result of thermal stress to the ignitors from the heatup and cooldown associated with the testing. The normal surveillance frequency requires this testing to be performed every 184 days (six months). At this frequency, the ignitors will be thermally cycled three times during an operating cycle. The TS Surveillance Requirement 3.6.9.3 to verify each ignitor is at a temperature greater than or equal to 1700'F is performed each refueling outage. This testing results in an additional thermal cycle, for a total of four thermal cycles per unit operating cycle.

Testing at a weekly frequency between now and the Fall 2014 Unit 1 refueling outage would be equivalent to normal frequency testing for thirteen operating cycles of eighteen months which is approximately eighteen and a half calendar years. I&M plans to replace all the Unit 1 ignitors during the Fall 2014 refueling outage as a plant modification using an improved ignitor design to improve long term reliability. This modification will assure that ignitors continue to remain reliable.

If more than one DIS Train A ignitor becomes inoperable, TS Surveillance Requirement 3.6.9.1 would require declaring Train A inoperable. If both DIS Train A and DIS Train B are declared inoperable, TS LCO 3.0.3 would apply because TS LCO 3.6.9 does not provide an Action for two inoperable DIS Trains. TS LCO 3.0.3 would require that the unit be in Mode 3 within 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br />.

3.4.3 Potential for Unit Shutdown Initiation Due to Monthly DG Surveillance Testing TS 3.8.1, "AC Sources - Operating," includes Surveillance Requirements that must be performed at the specified Frequency for the DG to be considered operable. Operability of the DGs is required for continued unit operation in Mode 1. Performance of some of these DG Surveillance Requirements necessitate declaring the DG inoperable due to the alignments necessary to perform the surveillance test. For the Train A DG, the next surveillance test that will render the DG inoperable is the test performed to satisfy TS Surveillance Requirement 3.8.1.3, which has a 31-day (monthly) frequency. This test requires that the DG be synchronized to a 4 kilovolt (kV) bus that is connected to offsite power, loaded, and operated for > 60 minutes at the specified load. During performance of this test, the DG is considered inoperable because, during the time that the DG output breakers are closed on the 4 kV bus, the bus would not experience a low voltage condition should the offsite power source be lost.

Because the low voltage condition will not occur, there will be no load-shed signal to remove non-essential loads from the bus. This in turn could result in an overload condition of the DG when it is forced to carry the normal loads on the bus with no other external power source.

With the DG inoperable during performance of this test, TS LCO 3.8.1 Condition B, "One required DG inoperable," will apply. One of the Required Actions for this condition, Required Action B.3, states that, with one DG inoperable, required features supported by the inoperable DG must be declared inoperable within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> when the required redundant feature is inoperable. Therefore, the inoperability of the Train A DG would require that, within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, Train A of the DIS be declared inoperable because the redundant DIS train (DIS Train B) is inoperable. If both DIS Train A and DIS Train B are declared inoperable, TS LCO 3.0.3 would apply because TS LCO 3.6.9 does not provide an Action for two inoperable DIS Trains. TS LCO 3.0.3 would require that the unit be in Mode 3 within 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br />.

to AEP-NRC-2013-84 Page 7 Review of operating logs indicates that performance of the monthly surveillance testing typically renders the DG inoperable for periods that could challenge the 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> allowed by TS LCO 3.8.1 Required Action B.3. With DIS Train B inoperable, unexpected issues or delays in the monthly performance of the Train A DG surveillance testing required by TS could result in entry into TS LCO 3.0.3. If the unexpected issues or delays were not resolved and the DG restored to operability within the 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> specified in TS LCO 3.8.1 Required Action B.3, initiation of a unit shutdown may be required.

3.4.4 Potential for Unit Shutdown Due to a Failure of the Train A DG If the Train A DG is rendered or found to be inoperable for more than 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> due to an equipment or component failure, entry into TS LCO 3.0.3 would be required similar to the manner described above regarding the planned monthly Train A DG inoperability. This sequence of events could result in requiring the unit to be in Mode 3 within 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br /> even though TS LCO 3.8.1 Required Action B.5 would allow the DG to be inoperable for 14 days without requiring a unit shutdown.

3.5 Reason for Requesting Approval on an Emergency Basis I&M is requesting approval of the proposed TS change on an emergency basis as permitted by 10 CFR 50.91(a)(5). The regulation at 10 CFR 50.91(a)(5) states that, where an emergency situation exists, in that failure to act in a timely way would result in shutdown of a nuclear power plant, the NRC may issue a license amendment involving no significant hazards consideration without prior notice and opportunity for a hearing or for public comment. The regulation states the NRC will decline to dispense with notice and comment on the determination of no significant hazards consideration if it determines that the licensee has abused the emergency provision by failing to make timely application for the amendment and thus itself creating the emergency.

Finally, the regulation states that a licensee requesting an emergency amendment must explain why the emergency situation occurred and why it could not avoid this situation.

I&M could not avoid the emergency circumstance because the discovery of two inoperable ignitors in the string powered by lower DIS Train B phase 3 and one inoperable ignitor in the string powered by lower DIS Train A phase 3 on October 4, 2013, could not have been foreseen in sufficient time to allow the 30 day public comment period specified in 10 CFR 50.91(2)(ii).

The electrical circuit design and location of the affected ignitor strings in areas of significant radiation and high temperature may preclude repairing the inoperable ignitors or even identifying which three individual ignitors are inoperable. Therefore, entry into TS LCO 3.6.9 Condition C Required Action C.1, requiring a unit shutdown no later than October 11, 2013, could not be avoided.

Even though TS 3.6.9 Condition B Required Action and Completion Time is the most limiting of the Conditions, if only the requested change to add Footnote 2 to address the containment regions is approved, then as described in Paragraph 3.4.3 above, continued weekly performance of TS Surveillance Requirement 3.6.9.1 on DIS Train A can be detrimental to the ignitors and may lead to a unit shutdown. I&M is requesting approval of the proposed change to include both footnotes by October 10, 2013, which would eliminate the requirement to perform surveillance testing of DIS Train A that week and weekly thereafter.

to AEP-NRC-2013-84 Page 8

4.0 TECHNICAL ANALYSIS

4.1 Capability of DIS to Perform Its Safety Function The function of the DIS is to assure adequate hydrogen control capacity during a degraded core cooling event. The distribution of ignitor assemblies throughout the containment promotes combustion of lean hydrogen/air/steam mixtures. Ignitors are located in areas well mixed by the CEQ System.

Operation of the CEQ System assures individual compartments are well-mixed, and the overall ice condenser containment is well-mixed, with air/gas flow assured through virtually every compartment in containment. Among the dead-ended compartments, only the regenerative heat exchanger room does not have a CEQ System connection. This room is normally closed from the rest of containment and water supplied to its heat exchangers is isolated automatically following receipt of a Phase A safety injection signal and low pressurizer water level signal, both of which would be expected to occur prior to significant core damage occurring that would lead to significant hydrogen generation. Mixing of gas constituents within the lower compartment of an ice condenser containment with hydrogen injection was experimentally verified by studies conducted at Hanford Engineering Development Laboratory that were documented in 1983 (Reference 1). Design air flow of the CEQ fans/ventilation system assure that gas constituents are recirculated and thereby mixed between containment compartments.

Direct ignition of the hydrogen within an area is not required to burn the hydrogen at low concentrations, which is the fundamental DIS objective. Burns ignited in one compartment readily propagate into adjacent compartments when the hydrogen concentration in the adjacent compartment exceeds the propagation limit. Propagation limits are lower than the ignition limits.

Typical empirical flame propagation limits are shown in NUREG/CR-4993, "A Standard Problem for HECTR-MAAP Comparison: Incomplete Burning." In addition, a description of flame propagation phenomena is included in NUREG/CR-4993.

Hydrogen combustion analyses performed for CNP using the MAAP3.0B computer code demonstrates the ability of the hydrogen control system to mitigate the consequences of the release of hydrogen into containment during postulated degraded core accidents. These analyses were submitted to the NRC by Reference 2. Given the focus of this analysis, the.

effects of flame propagation were not discussed. However, the effectiveness of burn propagation within containment was discussed in a report submitted by Duke Energy Company to the NRC in August 1993, "An Analysis of Hydrogen Control Measures at McGuire Nuclear Station." This report was referenced in a Duke Energy Company submittal (Reference 3) in support of a Catawba Nuclear Station Proposed Technical Specification Amendment which was approved as documented in Reference 4. The Duke Energy Company submittal states that the analysis clearly shows that propagation of burns between compartments is effective for initiating burns within compartments that have not yet reached the hydrogen concentration ignition limit.

The submittal includes details that document the propagation effectiveness of several sequences that were analyzed. Review of this report confirms that at the level of detail used in containment modeling, the CNP and Catawba containment arrangements are similar and the conclusions regarding flame propagation are applicable to CNP. This implies that hydrogen burns typically occur first in the lower compartment, followed by burns in the ice condenser upper plenum, and then (possibly) in the upper compartment.

to AEP-NRC-2013-84 Page 9 The significance of hydrogen burn propagation to surrounding areas is that complete containment coverage with ignition sources is not a requirement for effective hydrogen control.

The CEQ System suction and discharge locations provide for a well-mixed environment inside the containment. Ignition in any compartment is likely to result in combustion in every compartment that has accumulated hydrogen at the propagation limit. With lower containment as the region most likely to see the hydrogen source term, ignition occurs frequently in this compartment and would spread readily to the dead-ended compartments (such as steam generator or pressurizer enclosures) as well as up into and through the ice condenser into upper containment. Propagation of hydrogen deflagration flame fronts both within a compartment and between compartments assures that control of the hydrogen concentration in the containment would be effective with multiple ignitors unavailable.

Although the possibility of a degraded core event that would generate a significant concentration of hydrogen is remote, the DIS is still capable of adequately performing its intended design function with the three subject ignitors out of service using the remaining ignitors. CNP has safety related, redundant CEQ System fans that actuate within approximately two minutes of a high containment pressure signal (approximately 1 psig) providing added assurance that lower and upper compartment air is thoroughly mixed. The CEQ System fans and their associated hydrogen collection ducting will provide sufficient air/gas mixing for the areas where the non-functional ignitors are located to prevent hydrogen buildup. The hydrogen will be burned by other ignitors in the lower compartment or in the ice condenser upper plenum when the mixed air-hydrogen concentration exceeds flammable limits in the vicinity of other ignitors.

Containment air mixing ensures the potential does not exist for an isolated hydrogen buildup to excessive concentrations beyond those considered for CNP. Thus, the failure of the three lower containment ignitors should not result in any change to the hydrogen burn profiles. Since the hydrogen concentration remains low and pocketing which could lead to rapid burns and challenge containment is avoided, the original design continues to be met. Thus, the probability of a containment failure and associated radiological release is not significantly altered with respect to maintaining hydrogen concentrations low following a degraded core accident.

With two ignitors out of service in one of the potentially affected regions (Region 12, 13, 14, 15, or 16), and an additional igniter out of service in a different potentially affected region, the remaining ignitors provide sufficient capability to burn hydrogen such that the overall concentration of hydrogen in containment remains low and the DIS function would be maintained. The remaining ignitors are fully operable and capable of providing the required coverage to effect hydrogen ignition in the event of a severe accident causing fuel damage.

Specifically, for two ignitors inoperable in a steam generator or pressurizer enclosure, any hydrogen accumulated in the general area would be burned off by the combination of operation of the remaining operable ignitors in the area below the enclosure and deflagration propagation into the enclosure. For a steam generator enclosure, at least one ignitor in its connected steam generator enclosure would also be available to assure ignition in the shared space; for the pressurizer enclosure, the CEQ System fans assure a rapid volumetric turn-over (approximately once per 5 minutes) of the contained atmosphere so pressurizer enclosure hydrogen concentration would be expected to be similar to that in the area below the enclosure which is protected by fully operational ignitors. Similar reasoning applies to the remaining failed Train B Phase 3 ignitor.

to AEP-NRC-2013-84 Page 10 4.2 Risk Assessment The highly redundant nature of the DIS and CEQ system extends to its power supplies. The DIS and CEQ system have multiple power sources to provide assurance of their availability following as many different hypothetical scenarios as possible. Under normal conditions, the DIS and CEQ system are powered by the unit preferred offsite power source. If this supply is lost, DIS and the CEQ system are energized by the DGs. If the DGs are unavailable, then DIS and CEQ system power is provided by either the 69 kV alternate offsite power source or the Supplemental Diesel Generators.

Continued operation at full power until the next scheduled refueling outage would involve no increase in plant risk since the DIS safety function would be maintained. However, even assuming that the current failures constitute complete loss of Train B DIS function, the following quantitative risk estimates support the conclusion that there is only minimal safety consequence associated with the current DIS condition. Treating the ignitor failures as constituting a train failure would only cause a very small increase in plant risk due to large early release of radioactivity to the public. First, there is no associated increase in Core Damage Frequency (CDF) due to DIS unavailability because DIS operation is solely to mitigate post-core-damage conditions. Regarding post-core-damage risk, assuming that the entire B train of DIS is out of service causes an increase in Large Early Release Frequency (LERF) of 2E-8/year. Given that the next Unit 1 refueling outage is scheduled for October 2014, or about 1 year from now, the Incremental Large Early Release Probability (ILERP) for this hypothetical case is about 2E-8.

Note that this small postulated increase in plant risk is offset by avoidance of plant risks associated with a plant shutdown. For CNP, each shutdown has a Conditional Core Damage Probability (CCDP) of 7.6E-7 and a Conditional Large Early Release Probability (CLERP) of 5.9E-8.

4.3 Hydrogen Recombiners The hydrogen recombiners are designed to preclude the hydrogen concentration in containment, following a DBA, from reaching a level that would require mitigation by the hydrogen ignitors. Technical Requirements Manual 8.6.3, "Hydrogen Recombiners" requires that two hydrogen recombiners be operable with the unit in Mode 1 or Mode 2. The hydrogen recombiners, therefore, provide defense-in-depth for protection of the containment against the potential effects of a post accident hydrogen build-up.

4.4 Conclusion 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. I&M has evaluated the consequences of this request from a safety standpoint and the results were found to be acceptable for the following reasons: the safety-related, redundant CEQ System fans are capable of providing a thoroughly mixed containment atmosphere; the remaining operable ignitors have been demonstrated to provide acceptable coverage for all containment regions that may be impacted as a result of hydrogen generation during a severe accident; any hydrogen not consumed in the lower compartment would be burned in the ice condenser upper to AEP-NRC-2013-84 Page 11 plenum or upper compartment; and there is a low probability of a LERF sequence being negatively impacted during the period the TS change is applicable.

4.5 Basis for Specific TS Changes The reasons for the specific changes to TS 3.6.9. are as follows:

4.5.1 Addition of Two Footnotes to TS Pages 3.6.9-1 and 3.6.9-2 The two footnotes added to both pages of TS 3.6.9 will clearly establish the limitations of the allowance provided by this proposed amendment, i.e., the specific ignitor strings that may contain an inoperable ignitor and the period during which the allowance is in effect. The requirement that, during the remainder of Fuel Cycle 25, the ignitors be replaced if the unit enters a MODE which allows replacement, provides assurance that the condition necessitating this proposed amendment will be addressed at the earliest opportunity while allowing for assessment of specific radiation and temperature hazards to personnel.

4.5.2 Addition of a Reference to Footnote 1 and 2 to TS LCO 3.6.9 The addition of a reference to footnote 1 to the first part of TS LCO 3.6.9 will clearly indicate that Train B, one of the two trains that are required to be operable by the LCO, is considered operable even though two ignitors in Train B are inoperable.

The addition of a reference to footnote 2 to the second part of TS LCO 3.6.9 will clearly indicate that requirement that each region have at least one operable ignitor does not apply to one of the identified regions (Region 12, 13, 14, 15, or 16).

4.5.3 Addition of a Reference to Footnote 1 to TS LCO 3.6.9 Condition A The addition of a reference to footnote 1 to TS LCO 3.6.9 Condition A will clearly indicate that the stated condition, "One DIS train inoperable," does not apply to Train B even though two ignitors are inoperable.

4.5.4 Addition of a Reference to Footnote 2 to TS LCO 3.6.9 Condition B The addition of a reference to footnote 2 to TS LCO 3.6.9 Condition B will clearly indicate that the stated condition, "One containment region with no OPERABLE hydrogen ignitor," does not apply to one of the following region: Region 12, 13, 14, 15, or 16. If in the future, more than one of the identified regions is determined to have no operable ignitors, or a region other than those identified is determined to have no operable ignitors, Condition B and its associated Required Action and Completion Time would apply.

4.5.5 Addition to Surveillance Requirement 3.6.9.1 of "->33 Ignitors if allowed by footnote 1" The addition to Surveillance Requirement 3.6.9.1 of "->33 Ignitors if allowed by footnote 1" will clearly establish that -> 33 rather than Ž 34 ignitors are required to be operable to consider Train B operable, will establish that Train B may contain two inoperable ignitors, and will establish the period during which those ignitors may be inoperable.

to AEP-NRC-2013-84 Page 12 4.5.6 Addition of a Reference to Footnote 2 to Surveillance Requirement 3.6.9.2 The addition of a reference to footnote 2 to Surveillance Requirement 3.6.9.2 will clearly establish that, when the surveillance test is performed, the Surveillance Requirement can be considered met even if the surveillance data indicates that one of the identified regions may have no operable ignitors.

4.5.7 Addition of a Reference to Footnote 1 to Surveillance Requirement 3.6.9.3 The addition of a reference to footnote 1 to Surveillance Requirement 3.6.9.3 will clearly indicate that, although there are two ignitors in one specified string that may not satisfy the requirement to achieve a temperature > 1700 0 F, DIS Train B is still considered operable for the specified period.

5.0 REGULATORY SAFETY ANALYSIS 5.1 No Significant Hazards Consideration Pursuant to 10 CFR 50.90, Indiana Michigan Power Company (I&M), the licensee for Donald C. Cook Nuclear Plant (CNP) Unit 1, proposes to amend the Appendix A Technical Specifications (TS) to Facility Operating License DPR-58. I&M proposes to modify the TS for the Distributed Ignition System (DIS). The DIS is designed to initiate controlled ignition of hydrogen resulting from a postulated accident via a system of 70 ignitors (two trains of 35 ignitors) located inside containment. The existing TS require that at least 34 of 35 ignitors in a train be operable to consider the train operable. Recent surveillance data indicates that two Train B ignitors are inoperable. Additionally, the existing TS require that each containment region have at least one operable ignitor. Recent surveillance data indicates that one of five regions may have no operable ignitors due to one Train A Phase 3 ignitor inoperable and two Train B Phase 3 ignitors inoperable. Replacement of the three ignitors with the unit operating at power would involve significant personnel radiation exposure and safety hazards. The proposed TS modification would allow Train B of the DIS to be considered operable with 33 operable ignitors and no operable ignitor in one of the five regions, because DIS will remain capable of performing its safety function. The proposed TS modification would be applicable until the Fall 2014 refueling outage, or until the unit is shut down and cooled down for other reasons prior to the Fall 2014 refueling outage. I&M has evaluated whether a significant hazards consideration is involved with the proposed amendment by focusing on the three standards set forth in 10 CFR 50.92, "Issuance of amendment," as discussed below:

1. Does the proposed change involve a significant increase in the probability of occurrence or consequences of an accident previously evaluated?

Response: No The postulated event involving operability of the DIS is a beyond-design basis accident that generates a quantity of hydrogen from the reaction of the fuel cladding with water that is far in excess of the hydrogen release calculated for the limiting design basis accident. The DIS has been evaluated and is designed to mitigate this event. The proposed change will not to AEP-NRC-2013-84 Page 13 increase the probability of such an accident because the DIS performs an entirely mitigative function. Except for brief periods of surveillance testing, the DIS is not in use during normal unit operation. The proposed change will not result in any physical changes to the plant which would affect accident initiators. Those structures, systems, and components (SSCs) involved in the initiation of postulated accidents will not be operated in any different manner.

Therefore, the probability of occurrence of a previously evaluated accident will not be significantly increased.

I&M's evaluation has determined that DIS will remain capable of performing its intended safety function of initiating controlled ignition of hydrogen resulting from a postulated beyond-design basis accident. I&M's evaluation has demonstrated that propagation of hydrogen burning initiated by ignitors that remain operable will ensure adequate combustion in the regions potentially affected by the inoperable ignitors. Therefore, continued assurance of containment integrity would be provided following a postulated beyond-design basis accident even if significant quantities of hydrogen were generated. With containment integrity maintained, there would be no increase in radiation releases from such an accident.

Additionally, the hydrogen concentration resulting from a design basis accident can be maintained less than the flammability limit using the hydrogen recombiners. Therefore, the consequences of a previously evaluated accident will not be significantly increased.

Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.

2. Does the proposed change create the possibility of a new or different kind of accident from any accident previously evaluated?

Response: No The proposed change does not alter the design function or operation of any SSC that may be involved in the initiation of an accident. The DIS will not become the source of a new type of accident. No new accident causal mechanisms will be created. The proposed change does not create new failure mechanisms, malfunctions, or accident initiators.

Therefore, the proposed change does not create the possibility of a new or different kind of accident from any previously evaluated.

3. Does the proposed change involve a significant reduction in a margin of safety?

Response: No The margin of safety involved with the DIS is that associated with protecting containment integrity from the potentially deleterious effects of a significant hydrogen accumulation following a beyond-design basis accident. I&M's evaluation has determined the DIS will remain capable of performing its intended safety function of initiating controlled ignition of hydrogen resulting from such an accident, thereby assuring that the associated margin of safety for the containment will be maintained. Therefore, there is no significant reduction in a margin of safety as a result of the proposed amendment.

to AEP-NRC-2013-84 Page 14 Therefore, the proposed change does not involve a significant reduction in the margin of safety.

Based on the above, I&M concludes that the proposed amendment presents no significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of "no significant hazards consideration" is justified.

5.2 Applicable Regulatory Reguirements/Criteria 10 CFR 50.44(b)(2)(ii) requires that all pressurized water reactors with ice condenser containments must have the capability for controlling combustible gas generated from a metal-water reaction involving 75 percent of the fuel cladding surrounding the active fuel region (excluding the cladding surrounding the plenum volume) so that there is no loss of containment structural integrity. I&M's evaluation has determined that the DIS will continue to perform this function at CNP with two inoperable ignitors on Train B and one of the identified regions having no operable ignitor. Regulatory guidance documents, such as the Standard Review Plan and associated Regulatory Guides do not provide specific criteria regarding the locations of hydrogen ignitors in those containments using ignitor systems to comply with 10 CFR 50.44 requirements. Therefore, compliance with 10 CFR 50.44(b)(2)(ii) will be maintained.

6.0 ENVIRONMENTAL CONSIDERATION

S A review has determined that the proposed amendment would change a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or would change an inspection or surveillance requirement. However, the proposed amendment does not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluent that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure.

Accordingly, the proposed amendment meets the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.

7.0 PRECEDENTS The proposed change is specific to the ignitor string in which the Train B failed ignitors are located and the identified containment regions in which there may be no operable ignitor at CNP. However, two other nuclear power plants, Catawba Nuclear Station Unit 2 and Watts Bar Nuclear Plant Unit 1, and CNP Unit 2, received approval of TS changes that allowed operation for a limited period with two inoperable ignitors. The Catawba amendment and the Watts Bar amendment are documented in Reference 4 and Reference 5, respectively and the CNP Unit 2 Amendment is documented in Reference 6. The Watts Bar amendment, the Catawba amendment, and the CNP Unit 2 amendment were approved based, in part, on the operability of the remaining ignitors, and adequate hydrogen mixing in conjunction with ignition of lean mixtures which effectively precludes the formation of detonable concentrations. The Watts Bar amendment and CNP Unit 2 amendment were approved on an expedited basis to address the potential entry into LCO 3.0.3 if the unaffected ignitor train of DIS became inoperable either by two or more ignitors being inoperable on the unaffected train or if the DG providing power to the to AEP-NRC-2013-84 Page 15 unaffected ignitor train became inoperable. The Catawba amendment was approved on an emergency basis to address a potential unit shutdown because the two inoperable ignitors were the only ignitors in a region.

8.0 REFERENCES

1. Report prepared for the Electric Power Research Institute by Westinghouse Hanford Company, "Hydrogen Mixing and Distribution in Containment Atmospheres," NP-2669, dated March 1983.
2. Letter from E. E. Fitzpatrick, I&M, to T. E. Murley, NRC, "Hydrogen Control Program (10CFR50.44(c)), Submittal of Analyses," AEP:NRC:0500Y, dated February 26, 1993 (ADAMS Accession No. ML9303030121).
3. Letter from G. R. Peterson, Duke Energy Company, to NRC Document Control Desk, "Catawba Nuclear Station, Unit 2 Docket Number 50-414 Proposed Technical Specifications Amendment Technical Specification 3.6.9 Hydrogen Ignition System (HIS)," dated May 3, 2000 (ADAMS Accession No. ML003712857).
4. Letter from C. P. Patel, NRC, to G. R. Peterson, Duke Energy Corporation, "Catawba Nuclear Station, Unit 2 Re: Issuance of Amendment (TAC No. MA8805)," dated May 5, 2000, (ADAMS Accession No. ML003713019).
5. Letter from R. E. Martin, NRC, to 0. J. Zeringe, Tennessee Valley Authority, "Issuance of Amendment on Hydrogen Mitigation System, Watts Bar Nuclear Plant, Unit 1 (TAC No. MA1491)," dated June 9,1998 (ADAMS Accession No. ML020800059).
6. Letter from T. A. Beltz, NRC, to J. J. Jensen, I&M, "Donald C. Cook Nuclear Plant, Unit 2 -

Issuance of Exigent Amendment Re: The Containment Distributed Ignition System (TAC No. ME3129)," dated February 4, 2010 (ADAMS Accession No. ML100310038).

to AEP-NRC-2013-84 Page 16 TABLE 1 - Ignitor Strings Grouped by Power Supply Phase (op)

Bold font indicates ignitors involved in the proposed amendment.

Unit 1 - Train A Upper Ignitor Location Unit 1 - Train A Lower Ignitor Location Jp IBOX I GENERAL LOC ELEV p BOX [ GENERAL LOC ELEV A13 Upper spray hdr pltfrm 760' A19 On Bio shield wall 643' A14 Upper spray hdr pltfrm 760' A20 On Bio shield wall 640' A15 Upper spray hdr pltfrm 760' 644' A21 On Bio shield wall A16 Low spray hdr pltfrm 748' A22 On Bio shield wall 641' A17 Low spray hdr pltfrm 748' A23 On Bio shield wall 642' A18 Low spray hdr pltfrm 748' A24 On Bio shield wall 642' Al In upper ice cond 709' A25 Near acc rms 1&4 635' A2 In upper ice cond 709' A26 In acc rm 4 632' A3 In upper ice cond 709' 2 A27 Above CLV fan 3 632' 2 A4 In upper ice cond 709' A28 Near CLV fan 2 634' A5 In upper ice cond 709' A29 Above Prz relief tnk 618' A6 In upper ice cond 709' A30 In S/G 1 enclosure 689' A7 In upper ice cond 709' A31 In S/G 4 enclosure 689' A8 Out S/G 1 enclosure 662' A32 In Prz enclosure 689' A9 Out S/G 4 enclosure 662' A33 In S/G 3 enclosure 689' 3 A10 Out Prz enclosure 662' A34 In S/G 2 enclosure 689' Al1 Out S/G 3 enclosure 662' A35 Inst rm by air/Ik 623' A12 Out S/G 2 enclosure 662' Unit 1 - Train B Upper Ignitor Location Unit 1 - Train B Lower Ignitor Location Ip BOX GENERAL LOC G ELEV p BOX I GENERAL LOC ELEV B13 Upper spray hdr pltfrm 760' B19 On Bio shield wall 646' B14 Upper spray hdr pltfrm 760' B20 On Bio shield wall 646' B15 Upper spray hdr pltfrm 760' B21 On Bio shield wall 648' B16 Low spray hdr plffrm 748' B22 On Rio shield wall 648' B17 Low spray hdr pltfrm 748' B23 On Bio shield wall 646' B18 Low spray hdr pltfrm 748' B24 On Bio shield wall 646' B1 In upper ice cond 709' B25 Above CLV fan 1 630' B2 In upper ice cond 709' B26 Near acc rms 1&4 634' B3 In upper ice cond 709' 2 B27 Near acc rms 2&3 634' 2 B4 In upper ice cond 709' B28 In acc rm 2 634' B5 In upper ice cond 709' B29 On Bio shield wall 618' B6 In upper ice cond 709' B35 Ins rm near hatch 630' B7 In upper ice cond 709' B30 In S/G 1 enclosure 689' B8 Out S/G 1 enclosure 659' B31 In S/G 4 enclosure 689' B9 Out S/G 4 enclosure 659' 3 B32 In Prz enclosure 687' 3 B10 Out Prz enclosure 659' B33 In S/G 3 enclosure 689' B131 Out S/G 3 enclosure 659' B34 In S/G 2 enclosure 689' B12 Out S/G 2 enclosure 659' to AEP-NRC-2013-84 Page 17 TABLE 2 Bold font indicates ignitors involved in the proposed amendment.

Containment Region Igniter Nos.

1 A-13, B-13; A-14, B-14; A-15, B-15 2 A-16, B-16; A-17, B-17; A-18, B-18 3 A-i, B-1; A-2, B-2 4 A-3, B-3; A-4, B-4; A-5, B-5 5 A-6, B-6; A-7, B-7 6 A-11, B-11; A-12, B-12 7 A-8, B-8; A-9, B-9; A-10, B-10 8 A-25, B-25; A-26, B-26 9 A-27, B-27; A-28, B-28 10 A-35, B-35 11 A-19, B-19; A-20, B-20; A-21, B-21; 11__A-22, B-22; A-23, B-23; A-24, B-24 12 A-30, B-30 13 A-34, B-34 14 A-33, B-33 15 A-31, B-31 16 A-32, B-32 17 A-29, B-29 to AEP-NRC-2013-84 Page 18 Figure 1 Unit 1 - Containment Elevation 650 feet and Above The approximate locations of the Train A and Train B ignitor strings powered by lower containment phase 3 are indicated by arrows. (Train A ignitor A-35 not shown.)

QUAD III QUAD IV 315 135 45 QUAD II QUAD I

Enclosure 3 to AEP-NRC-2013-84 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

[footnote 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 a MODE 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 a MODE 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 verify > 34 ignitors Ior > 33 i nitors if allowed b ootnote 1 are energized in each train.

SR 3.6.9.2 Verify at least one hydrogen ignitor is OPERABLE in 184 days each containment region. I(See footnote 2 SR 3.6.9.3 Energize each hydrogen ignitor and verify 24 months temperature is > 1700 0 F. I(See footnote 1 Footnote 1: For the remainder of Fuel Cycle 25, or until the next entry into a MODE 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 a MODE which allows replacement of the affected ignitors, one of the following regions is allowed to have no OPERABLE ignitor: Region 12, 13, 14 Cook Nuclear Plant Unit 1 3.6.9-2 Amendment No. 287

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