Text

Phase 1 and Phase 2 Overall Integrated Plan in Response to June 6, 2013, Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (Order Number EA-13-109)
	ML15364A011
Person / Time
Site:	Cooper
Issue date:	12/21/2015
From:	Limpias O A; Nebraska Public Power District (NPPD)
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	EA-13-109, NLS2015137, TAC MF43 84
	Download: ML15364A011 (86)
	v • d • e

Nebraska Public Power District Always there wvhen you need us NLS2015 137 December 21, 2015 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-000 1

Subject:

References:

Nebraska Public Power District's Phase 1 and Phase 2 Overall Integrated Plan in Response to June 6, 2013, Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (Order Number EA-13 -109)Cooper Nuclear Station, Docket No 50-298, DPR-46 1. NRC Order Number EA-13-109, "Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions," dated June 6, 2013 2. NPPD letter to NRC, "Nebraska Public Power District's Phase 1 Overall Integrated Plan in Response to June 6, 2013, Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (Order Number EA- 13-109)," dated June 30, 2014 (NLS2014057)

3. NPPD letter to NRC, "Nebraska Public Power District's First Six-Month Status Report in Response to June 6, 2013, Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (Order Number EA-13-109)," dated December 19, 2014 (NLS2014101)

4. NRC letter to NPPD, "Cooper Nuclear Station -Interim Staff Evaluation Relating to Overall Integrated Plan in Response to Phase 1 of Order EA- 13-109 (Severe Accident Capable Hardened Vents) (TAC NO. MF43 84)," dated February 11, 2015

Dear Sir or Madam:

On June 6, 2013, the Nuclear Regulatory Commission (NRC) issued Order EA-13-109 (Reference

1) to Nebraska Public Power District (NPPD). Reference I was immediately effective and directs NPPD to take certain actions to ensure that Cooper Nuclear Station (CNS)has a hardened containment vent system (HCVS) to remove decay heat from the containment, and maintain control of containment pressure within acceptable limits following events that result in loss of active containment heat removal capability while maintaining the capability to operate under severe accident conditions resulting from an Extended Loss of AC Power.Specific requirements are outlined in Attachment 2 of Reference 1.COOPER NUCLEAR STATION P.O, Box 98 / Brownv/ile, NlE 68321-0098 Telephone:

(402) 825-3811 / Fax: (402) 825-52)1 w.vwnppd .com 4K NLS2015 137 Page 2 of 2 Reference 1 required submission of a Phase 1 overall integrated plan (OIP) pursuant to Section IV, Condition D, and status reports at six-month intervals thereafter.

NPPD submitted an initial OIP for CNS by letter dated June 30, 2014 (Reference

2) and a revised OIP by letter dated December 19, 2014 (Reference 3).The purpose of this letter is to provide both the third six-month update for Phase 1 of the Order pursulant to Section IV, Condition D.3, of Reference 1, and the OIP for Phase 2 of the Order pursuant to Section IV, Condition D.2 of Reference

1. The third six-month update for Phase 1 of the Order is incorporated into the attached HCVS overall integrated plan document which provides a complete updated Phase 1 OIP, a list of the Phase 1 OIP open items, and addresses the NRC Interim Staff Evaluation open items for Phase 1 contained in Reference

4. Future six-month status reports will provide the updates for both Phase 1 and Phase 20OIP implementation in a single status report.This letter contains no new regulatory commitments.

Should you have any questions concerning the content of this letter, please contact Jim Shaw, Licensing Manager, (402) 825-2788.I declare under penalty of perjury that the foregoing is true and correct.Executed on: I ViePeiet-ular and Chief Nuclear Officer/bk

Attachment:

Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan, Revision 2 cc: Regional Administrator, w/attachment USNRC -Region IV Director, w/attachment USNRC -Office of Nuclear Reactor Regulation Cooper Project Manager, w/attachment USNRC -NRR Project Directorate IV- 1 Senior Resident Inspector, w/attachment USNRC -CNS NPG Distribution, w/o attachment CNS Records, w/attachment Attachment to NLS2015137 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan, Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan CNS OIP CNS OIP ~Page l ot 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Jntegrated Plan (EA-1 3-1 09)Revision Summary Revision Date Description of Change 0 6/30/2014 Initial submittal.

1 12/15/2014 First Status Update. New Hardened Containment Venting Path (major rewrite).2 12/15/2015

Incorporated Phase 2 actions into one comprehensive Overall Integrated Plan* Finalizing the design resulted in: o Vent pipe size changed to 12" o Changed method of hydrogen control to no longer require a purge system o Changed method of rain/snow protection for release point o Removed need for a vacuum breaker* Minor editorial and formatting changes CNS OIP CNS OIP ~~Page 2 of 83 Rvso Revision 2 Part Part Part Part Part Part Part Part Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Table of Contents: 1: General Integrated Plan Elements and Assumptions 2: Boundary Conditions for Wet Well Vent 3: Boundary Conditions for EA-1 3-1 09. Option B.2 3.1 Boundary Conditions for SAWA 3.IA Boundary Conditions for SAWA/SAWM 3.1 B Boundary Conditions for SAWAISADV 4: Programmatic Controls, Training, Drills and Maintenance 5: Implementation Schedule Milestones Attachment Attachment Attachment Attachment Attachment Attachment Attachment Attachment Attachment Attachment Attachment Attachment 1: HCVS/SAWA Portable Equipment 2A: Sequence of Events Time!ime -HCVS 2.1 .A." Sequence of Events Timeline -SAWA / SAWM 2.1 .B: Sequence of Events Timeline -SADV 2.1.C: SAWA / SAWM Plant-Specific Datum 2.1.0: SAWM SAMG Approved Langquagqe 3: Conceptual/Final Sketches 4: Failure Evaluation Table 5: References 6: Changqes/Updates to this Overall Integqrated Implementation Plan 7: List of Overall Integrated Plan Open Items 8: List of Acronyms CNS OIP CNS OIP ~~Page 3 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overali Integrated Plan (EA-1 3-1 09)Introduction In 1989, the Nuclear Regulatory Commission (NRC) issued Generic Letter 89-16, Installation of a Hardened Wetwell Vent, to all licensees of boiling water reactors (BWR) with Mark I containmnents to encourage licensees to voluntarily install a hardened wetwel1 vent. In response, licensees installed a hardened vent pipe from the suppression pool to some point outside the secondary containment envelope (usually outside the reactor building).

Some licensees also installed a hardened vent branch line from the drywell.On March 19, 2013, the NRC Commissioners directed the staff per Staff Requirements Memorandum (SRM) for SECY 0157 to require licensees with Mark l and Mark II containments to "upgrade or replace the reliable hardened vents required by Order EA-1 2-050 with a containment venting system designed and installed to remain functional during severe accident conditions." In response, the NRC issued Order EA-1 3-109, Issuance of Order to Modifing Licenses with Regard to Reliable Hardened Containment Vents' Capable of Operation Under Severe Accidents, June 6, 2013. The Order (EA-1 3-109)requires that licensees of BWR facilities with Mark I and Mark II containment designs ensure that these facilities have a reliable hardened vent to remove decay heat from the containment, and maintain control of containment pressure within acceptable limits following events that result in the loss of active containment heat removal capability while maintaining the capability to operate under severe accident (SA) conditions resulting from an Extended Loss of AC Power (ELAP).The Order requirements are applied in a phased approach where: "Phase 1 involves upgrading the venting capabilities from the containment wetwel1 to provide reliable, severe accident capable hardened vents to assist in preventing core damage and, if necessary, to provide venting capability during severe accident conditions." (Completed "no later than startup from the second refueling outage that begins after June 30, 2014, or June 30, 2018, whichever comes first.")"Phase 2 involves providing additional protections for severe accident conditions through installation of a reliable, severe accident capable drywell vent system or the development of a reliable containment venting strategy that makes it unlikely that a licensee would need to vent from the containment drywell during severe accident conditions." (Completed

"'no later than startup from the first refueling outage that begins after June 30, 2017, or June 30, 2019, whichever comes first.")The NRC provided an acceptable approach for complying with Order EA- 13-109 through Interim Staff Guidance (ISG) (JLD-ISG-2013-02 issued in November 2013 and JLD-ISG-2015-0l issued in April 2015). The IS~s endorse the compliance approach presented in NEI 13-02 Revision 0 and I, Compliance with Order EA-1 3-1 09, Severe Accident Reliable Hardened Containment Vents, with clarifications.

Except in those cases in which a licensee proposes an acceptable alternative method for complying with Order EA-13-109, the NRC staff will use the methods described in the IS~s to evaluate licensee compliance as presented in submittals required in Order EA-13-109.

The Order also requires submittal of an overall integrated plan (Oil') which will provide a description of how the requirements of the Order will be achieved.

This document provides the OIP' for complying with Order EA-13-109 using the methods described in NEI 13-02 and endorsed by NRC JLD-ISG-2013

-02 and JLD-ISG-2015

-01.Six month progress reports will be provided consistent with the requirements of Order EA-13-109.

CNS OIP CNS OIP ~~Page 4 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overail Integrated Plan (EA-1 3-1 09)The submittals required are: OIP' for Phase 1 ofEBA-i13-109 was required to be submitted by Licensees to the NRC by June 30, 2014. The NRC requires periodic (6 month) updates for the Hardened Containment Vent System (HCVS) actions being taken. The first update for Phase 1, was due December 2014, with the second due June 2015.OiP' for Phase 2 of EA-13-109 is required to be submitted by Licensees to the NRC by December 31, 2015. It is expected the December 2015 six month update for Phase I will be combined with the Phase 20OP submittal by means of a combined Phase 1 and 20OW.*Thereafter, the 6 month updates will be for both the Phase 1 and Phase 2 actions until complete, consistent with the requirements of Order EA-13-1 09.Note: At the Licensee's option, the December 2015 six month update for Phase 1 may be independent of the Phase 2OIP' submittal, but will reqluire separate six month updates for Phase 1 and 2 until each phase is in compliance.

The Plant venting actions for the EA-1 3-109, Phase 1 severe accident capable venting scenario can be summarized by the following:

The IZCVS will be initiated via manual action from the either the Main Control Room (MCR)(some plants have a designated Primary Operating Station (P05) that will be treated as the main operating location for this order) or from a Remote Operating Station (ROS) at the appropriate time based on procedural guidance in response to plant conditions from observed or derived symptoms.* The vent will utilize Containment Parameters of Pressure and Level from the MCR instrumentation to monitor effectiveness of the venting actions.*The vent operation will be monitored by HCVS valve position, temperature, and effluent radiation levels.* The HCVS motive force will be monitored and have the capacity to operate for 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months with installed equipment.

Replenishment of the motive force will be by use of portable equipment once the installed motive force is exhausted.

Venting actions will be capable of being maintained for a sustained period of up to 7 days or a shorter time if justified.

The Phase 2 actions can be summarized as follows:*Utilization of Severe Accident Water Addition (SAWA) to initially inject water into the Reactor Pressure Vessel (RPV).*Utilization of Severe Accident Water Management (SAWM) to control injection and Suppression Pool level to ensure the HCVS (Phase 1) wetwell vent (SAWV) will remain ftnctional for the removal of decay heat from containment.

CNS OIP CNS OIP ~Page 5Sof3 Reiio3 Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Ensure that the decay heat can be removed from the containment for seven (7) days using the HCVS or describe the alternate method(s) to remove decay heat from the containment from the time the HCVS is no longer fuinctional until alternate means of decay heat removal are established that make it unlikely the Drywell vent will be required for Drywell pressure control.*The SAWA and SAWM actions will be manually activated and controlled from areas that are accessible during severe accident conditions.

Parameters measured should be Dryzwell pressure, Suppression Pool level, SAWA flowrate and the BCVS parameters listed above.*Alternatively SAWA and a Severe Accident Capable Drywell Vent (SADV) strategy may be implemented to meet Phase 2 of Order EA-13-109.

CNS OIP CNS alp ~Page 6Sof 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overali Integrated Plan (EA-1 3-lo9)Part 1: General Integrated Plan Elements and Assumptions Extent to which thle guidance, .JLD-ISG-2013-02, .JLD-ISC-2015-01 and NET 13-02 (Revision 1), are being followed.

Identify any deviations.

Include a description of any alternatives to the guidance.

A technical justi(fication and basis for the alternative needs to be provided.

This will likely require a pre-meeting with the NRC to review the alternative.

Ref: JLD-ISG-2013-02, JLD-ISG-2015-01-Compliance will be attained for CNS with no known deviations to the guidelines in JLD-ISG-2013-02, JLD-ISG-2015-01 and NEI 13-02 for each phase as follows:*The HCVS will be comprised of installed and portable equipment and operating guidance:*Severe Accident Wetwell Vent (SAWV) -Permanently installed vent from the Suppression Pool to the top of the Reactor Building.* Severe Accident Water Addition (SAWA) -A combination of permanently installed and port able equipment to provide a means to add water to the RPV following a severe accident and monitor system and plant conditions.

Severe Accident Water Management (SAWM) strategies and guiidance for controlling the water addition to the RPV for the sustained operating period. (Reference Attachment 2.1 .D)*Phase 1 (wetwell):

by the startup from the second refueling outage that begins after June 30, 2014, or June 30, 2018, whichever comes first. Currently scheduled for 4th Quarter (November) of 2016.*Phase 2 (alternate strategy):

by the startup from the first refueling outage that begins after June 30, 2017, or June 30, 2019, whichever comes first. Currently scheduled for 4th Quarter (November) of 2018.If deviations are identified at a later date, then the deviations will be communicated in a future 6 month update following identification.

State applicable extreme external hazard from NET 12-06, Section 4.0-9.0 List resultant determination of screened in hazards from the EA-12-049 Compliance.

SRef: NET 13-02 Section 5.2.3 and D.1.2 The following extreme external hazards screen-in for CNS:*Seismic, Extreme Cold, High Wind, Extreme High Temperature The following extreme external hazards screen out for CNS: External Flooding CNS OIP Page 7 of 83 Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 1: General Integrated Plan Elements and Assumptions Key site assumptions to implement NEL 13-02 IICVS, Phase 1 and 2 Actions.Provide key assumptions associated with implementation of HC VS Phase 1 antd Phase 2 Actions.Ref: NET 13-02, Revision 1, Section 2 NEI 12-06, Revision 0 Mark I/II Generic EA-13-109 Phase 1 and Phase 2 Related Assumptions:

Applicable EA-12-049 assumptions:

049-1. Assumed initial plant conditions are as identified in NEI 12-06, Section 3.2.1.2, items 1 and 2 (Reference 10).049-2. Assumed initial conditions are as identified in NET 12-06, Section 3.2.1.3, items 1, 2, 4,5, 6 and 8 (Reference 10).049-3. Assumed reactor transient boundary conditions are as identified in NET 12-06, Section 3.2.1.4, items 1, 2, 3 and 4 (Reference 10).049-4. No additional events or failures are assumed to occur immediately prior to or during the event, including security events except for failure of RCIC or HPCJ (Reference 10, NEI 12-06, Section 3.2.1.3, item 9).049-5. At Time=0 the event is initiated and all rods insert and no other event beyond a common site ELAIP is occurring at any or all of the units (Reference 10, NET 12-06, Section 3.2.1.3, item 9 and 3.2.1.4 items 1-4).049-6. At 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months an ELAP is declared and actions begin as defined in EA-12-049 compliance.

049-7. DC power and distribution can be credited for the duration determined per the EA-12-049 (FLEX)methodology for battery usage, (greater than 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months with a calculation limiting value of 9 hours1.041667e-4 days 0.0025 hours 1.488095e-5 weeks 3.4245e-6 months ). This assumption applies to the water addition capability under SAWA/SAWM.

The power supply scheme for the HCVS shall be in accordance with EA-13-109 and the applicable guidance (Reference 10, NEI 12-06, Section 3.2.1 .3, item 8).049-8. Deployment resources are assumed to begin arriving at hour 6 and fully staffed by 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .049-9. All activities associated with plant specific EA-1 2-049 FLEX strategies that are not specific to implementation of the HCVS, including such items as debris removal, communication, notification, SFP level and makeup, security response, opening doors for cooling, and initiating conditions for the event, can be credited as previously evaluated for FLEX (Refer to assumption 109-02 below for clarity on SAWA)(HCVS-FAQ-11).Applicable EA-13-109 generic assumptions:

109-01. Site response activities associated with EA-13-109 actions are considered to have no access limitations associated with radiological impacts while RPV level is above 2/3 core height (core damage is not expected).

This is further addressed in HCVS-FAQ-12.

109-02. Portable equipment can supplement the installed equipment after 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months provided the portable equipment credited meets the criteria applicable to the IICVS. Ant example is use of FLEX portable air supply equipment that is credited to recharge air lines for HCVS components after 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . The FLEX portable air supply used must be demonstrated to meet the "SA Capable" criteria that are defined in NET 13-02, Section 4.2.4.2, and Appendix D, Section D.l1.3. This assumption does not apply to Phase 2 SAWA/SAWM because SAWA equipment needs to be connected and placed in service within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months from the time of the loss of RPV injection. (Reference 51, IHCVS-FAQ-12).

109-03. SFP level is maintained with either on-site or off-site resources such that the SFP does not contribute to the analyzed source term (Reference 20, IICVS-FAQ-07).

CNS OIP CNS OIP ~~Page 8 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overail Integrated Plan (EA-1 3-1 09)Part 1: General Integrated Plan Elements and Assumptions 109-04. Existing containment components design and testing values are governed by existing plant primary containment criteria (e.g., Appendix J) and are not subject to the testing criteria from NEI 13-02 (Reference 18, HCVS-FAQ-05 and Reference 11, NET 13-02, Section 6.2.2).109-05. Classical design basis evaluations and assuniptions are not required when assessing the operation of the HCVS. The reason this is not required is that the order postulates an unsuccessful mitigation of an event such that an ELAP progresses to a severe accident with ex-vessel core debris which classical design basis evaluations are intended to prevent (Reference 11, NEI 13-02, Section 2.3.1).109-06. HCVS manual actions that require minimal operator steps and can be performed in the postulated thermal and radiological environment at the location of the step(s) (e.g., load stripping, control switch manipulation, valving-in nitrogen bottles) are acceptable to obtain HCVS venting dedicated functionality (Reference 14, HCVS-FAQ-01).

This assumption does not apply to Phase 2 SAWA/SAWM because SAWA equipment needs to be connected and placed in service within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months from the time of the loss of RPV injection and will require more than minimal operator action.109-07. HCVS dedicated equipment is defined as vent process elements that are required for the HCVS to function in an FLAP event that progresses to core melt ex-vessel (Reference 15, HCVS-FAQ-02 and Reference 23, White Paper HCVS-WP-01).

This assumption does not apply to Phase 2 SAWA!SAWM because SAWA equipment is not dedicated to HCVS but shared to support FLEX functions.

This is further addressed in Reference 50, HCVS-FAQ-1 I.109-0 8. Use of MAAP Version 4 or higher provides adequate assurance of the plant conditions (e.g., RPV water level, temperatures, etc.) assumed for Order BA-i13-109 BDBEE and SA HCVS operation. (Reference 31, FLEX MAAP Endorsement ML13190A201).

Additional analysis using RELAP5/MOD 3, GOTHIC, PCFLUD, LOCADOSE and SHIELD are acceptable methods for evaluating environmental conditions in areas of the plant provided the specific version utilized is documented in the analysis.

MAAP Version 5 was used to develop Technical Report 3002003301 to support drywell temperature response to SAWA under severe accident conditions.

109-09. NRC Published Accident evaluations (e.g., SOARCA, SECY-12-0 157, and NUREG 1465) as related to Order EA-13-109 conditions are acceptable as references (Reference 11, NET 13-02, Section 8).109-10. Permanent modifications installed or planned per EA-12-049 are assumed implemented and may be credited for use in EA- 13 -109 Order response.109-11. This OIP' is based on FOP changes consistent with EPG/SAGs Revision 3 as incorporated per the sites EOP/SAMG procedure change process. This assumption does not apply to Phase 2 SAWM because SAWM is not part of Revision 3 (Reference Attachment 2.1.D for SAWM SAMO Changes approved by the BWROG Emergenlcy Procedures Committee).

109-12. Under the postulated scenarios of Order BA-i13-109 the Control Room is adequately protected from excessive radiation dose due to its distance and shielding from the reactor (per GDC 19 in 10OCER50 Appendix A) and no further evaluation of its use as the preferred HCVS control location is required provided that the HCVS routing is a sufficient distance away from the MCR or is shielded to minimize impact to the MCR dose. In addition, adequate protective clothing and respiratory protection are available if required to address contamination issues (Reference 14, HCVS-FAQ-01 and Reference 22, HCVS-FAQ-09).109-13. The suppression pool/wetwell of a BWR Mark UI/I containment is considered to be bounded by assuming a saturated environment for the duration of the event response because of the water/steam interactions.

109-14. RPV depressurization is directed by the EPGs in all cases prior to entry into the SAGs (Reference i11, NEI 13-02 Rev 1, §I.1.3).109-15. The Severe Accident impacts are assumed on one unit only due to the site compliance with NRC Order EA-12-049.

However, each BWR Mark l and II under the assumptions of NRC Order EA-13-109 ensures the capability to protect containment exists for each unit (Reference 14, HCVS-FAQ-0 1). This is further addressed in Reference 49, HCVS-FAQ-10.

CNS OIP Page 9 of 83 Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 1: General Integrated Plan Elements and Assumptions Plant Specific HCVS Related Assumptions/Characteristics:

CNS-1I The plant layout of buildings and structures are depicted in the following Figure 1-1 (Cooper Nuclear Station Layout). Note that CNS includes only one unit. The MCR is located in the Control Building at elevation 932'-6" (ground level of the Control Building is 903'-6"), which is to the north of the Reactor Building (ground level is 903').CNS-2 The existing THPV line will not be used. A new HCVS vent line will be installed inside the Reactor Building.CNS-3 The effluent will be released from the top of the Reactor Building.CNS-4 A Mechanical ROS (nitrogen station) will be installed to provide additional pneumatic supply to the HCVS air-operated valves after 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . In addition, the nitrogen station will act as a remote operating station for the operation of the air-operated valves. The Mechanical ROS will be located against the south exterior wall of the Reactor Building.CNS-5 The CNS HCVS includes a UPS which is sized to provide power for at least 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months for the HCVS components and the HCVS instrumentation and indication in the MCR and at the Mechanical ROS. The UPS will be located at the far end of the Control Building corridor at the 903' -6" level.CNS-6 An additional UPS system will be installed in the Reactor Building to provide power to the inboard PCIV.CNS-7 Hydrogen control will be addressed using a check valve combined with limiting the run-up distance of the piping downstream of the check valve.Figure 1-1, Cooper Nuclear Station Layout CNS OIP CNS OIP ~~Page 10 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 2:_Boundary Conditions for Wet Well Vent Provide a sequence of events and identify any time or environmental constraint required for success including the basis for the constraint.

HCVS Actions that have a time cons traint to be successful should be identified with a technical basis and a justification provided that the time can reasonably be met (for example, action to open vent valves).HCVS Actions that have an environmental constraint (e.g. actions in areas of High Thermal stress or High Dose areas) should be evaluated per guidance.Describe in detail in this section the technical basis for the constraints identified on the sequence of events timeline attachment.

See attached sequence of events timeline (Attachment 2A).Ref: EA-13-109 Section 1.1.1, 1.1.2, 1.1.3 / NEI 13-02 Section 4.2.5, 4.2.6. 6.1.1 The operation of' the HCVS will be designed to minimize the reliance on operator actions in response to hazards listed in Part 1. Initial operator actions will be completed by plant personnel and will include the capability for remote-manual initiation from the HCVS control station. A list of the remote manual actions performed by plant personnel to open the HCVS vent path can be found in the following table (2-1). An HCVS ELAP Failure Evaluation table, which shows alternate actions that can be performed, is included in Attachment 4.Table 2-1, HCVS Remote Manual Actions Primary Actions Primary Location / Notes Component 1. Manually switch PC- Reactor Building, This dedicated UPS provides MOV-233MV power from elevation 958'-3", at or three operating cycles of PC-Division I AC to dedicated near MCC-RA MOV-233MV.

This valve is 2. Ensure N 2 purge to torus MCR Vertical Board H This valve is normally closed, valve AO-239 is closed. fails-closed.

CC)"tfl 3. Ensure torus inlet purge MCR Vertical Board H This valve is normally closed,c shutoff valve AO-235 is fails-closed.

o~closed.4. Place PC-MO-233 MCR Key PA2235 ISOLATION OVERRIDE Panel P2to OVERRIDE.5. Place PC-AO-237 MCR Key PA2235 p. ISOLATION OVERRIDE Panel P2~to OVERRIDE.6. Open torus inlet outboard MCR Vertical Board H This valve is normally closed, isolation valve PC-AO- and fails-closed on loss of air or 237AV. electricity.

~Controlled from ROS panel, as~well.CNS OIP Page 11 of 83 Revision Cooper Nuclear Station Hardened Containment Venting System Overall integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet WellVent 7. Open torus inlet inboard isolation valve PC-MO-233MV.MCR Vertical Board H This valve is normally closed.8.Open torus HCVS valve PC-AO-32.MCR Key PA2235 Panel P2 AO-32 is the venting valve.This valve is normally closed, and fails-closed on loss of air and electricity.

Controlled from ROS panel, as well.9. Connect FLEX DG to emergency connection of the UPS system.HCVS UPS in Control Building Corridor Prior to depletion of the HCVS dedicated power supply (the UPS battery);

actions will be required to connect back-up sources at a time greater than 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .C U Ca V Ca 0 10. Switch UPS power from HCVS UPS in Control Prior to depletion of the HCVS 120 VDC battery to Building Corridor dedicated power supply (the bypass source. UPS battery), actions will be required to connect back-up sources at a time greater than 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .11. Replenish pneumatics with replaceable nitrogen bottles to pre-installed connections.

Mechanical ROS N 2 bottles will be located in an area accessible to operators (by ROS).Nitrogen bottles will be pre-connected at the Mechanical ROS. Prior to depletion of the pneumatic sources, actions will be required to connect back-up sources at a time greater than 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .Provide a sequence of events and identify any time or environmental success including the basis for the constraint constraint required for A timelinte was developed to identify required operator response times and potential environmental constraints.

This timeline is based upon the following three eases: 1. Case 1 is a based upon the action response times developed for FLEX when utilizing anticipatory venting ini a BDBEE without core damage.2. Case 2 is based on a SECY-12-0157 long term station blackout (LTSBO) (or ELAP) with failure of RCIC after a black start where failure occurs because of subjectively assuming over injection.

3Y Case 3 is based on NUREG-1935 (SOARCA) results for a prolonged SBO (or ELAP) with the loss of RCIC case without black start.CNS OIP Page 12 of 83 Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Part 2: Boundary Conditions for Wet Well Vent The following is a discussion of time constraints identified in Attachment 2A for the 3 timeline cases identified above:*8 hours: Initiate use of HCVS per site procedures to maintain containment parameters below design limits and within the limits that allow continued use of RCIC. The reliable operation of IICVS will be met because HCVS meets the seismic requirements identified in NEI 13-02 and will be powered by a dedicated HCVS DC powered UPS (the "UPS" system mentioned below) with motive force supplied to HCVS valves from installed accumulators and portable nitrogen storage bottles. Critical HCVS controls and instruments associated with containment will be powered by two UIPS systems described below and in "Part 2 -HCVS Support Equipment Functions" of this document, and operated from the MCR. HCVS battery capacity will be available to extend to 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . In addition, when available, Phase 2 FLEX DO can provide power before battery life is exhausted.

Thus, initiation of the I-C VS from the MCR within S hours is acceptable because the actions can be performed any time after declaration of an ELAP until the venting is needed at 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months for BDBEE venting. This action can also be performed for SA HCVS operation which occurs at a time further removed from an ELAP declaration as shown in Attachment 2A.oDedicated HCVS battery capacity will be available from two UPS systems (Sketch 1 in Attachment

3) to provide power for at least 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . The HCVS UPS will provide power to the HCVS components and the HCVS instrumentation and indication in the MCR and at the Mechanical ROS until the FLEX DG is ready to be put in service. This system will consist of a bank of battery cells providing 12OVDC powering an inverter, which supplies alternate HCVS 12OVAC power, and a 120 VAC Distribution Panel. The inboard PCIV! (PC-MOV-233MV) will be powered by a separate, dedicated UPS (PC233MV UPS). Therefore, providing power to the UPS is under no time constraint until at least 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .*24 hours: If station power is not restored after 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , power to the HCVS Distribution Panel will be provided directly by a FLEX DO (bypassing the UIPS battery charger) or by recharging the UPS batteries with a FLEX DO. The transfer switch will be aligned to supply normal AC power to the battery charger during normal operation.

During the beyond design basis event, cables will be connected to the receptacles installed on the transfer switch enclosure and connected to the cables from a FLEX DO.*24 hours: AOVs PC-AOV-237AV and PC-AOV-A032 will be supplied pneumatic motive force using portable nitrogen bottles pre-staged and pre-connected in thle Mechanical ROS. Although the valves can be supplied pneumatic motive force from the Mechanical ROS at any time prior to 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , the accumulators of PC-AOV-237AV and PC-AOV-A032 will be sized to provide enough pneumatic supplies for 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .Hence, this time constraint is not limiting.Discussion of radiological and temperature constraints identified in Attachment 2A:*Actions to initiate HCVS operation are taken from the MCR, or from the ROS if operation of PC-AOV-237AV and PC-AOV-A032 require nitrogen from the Mechanical ROS. As per assumption 109-12, the Control Room is adequately protected from excessive radiation dose per ODC 19 in IOCFR5O Appendix A.Non-radiological habitability for the MCR is being addressed as part of the FLEX response (Reference 28).* The Mechanical ROS will be located against the South wall of the Reactor Building, on the exterior side.* To transfer power to the PC-MOV-233MV dedicated PC233MV UPS, operators will be required to travel to the transfer switch located in the Reactor Building near the MCC-RA (floor elevation 958' -3").CNS QIP Page 13 of 83 Revision 2 v Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Part 2: Boundary Conditions for Wet Well Vent This operation will be performed after an ELAP is declared, but before venting of the HCVS is initiated.

The core will still be covered and no additional radiological conditions will be experienced at the location of the connection.

A formal calculation to evaluate the accessibility of the Mechanical ROS and other non-MCR locations (e.g., Control Building, and Reactor Building 958'-3" near MCC-RA) for radiological and environmental conditions will be performed.

This calculation will also confirm travel pathways accessibility to the Mechanical ROS and other non-MCR locations in order to minimize operator exposure to adverse environmental conditions.

OPEN ITEM I: Determine the location of the HCVS ROS. (COMPLETE)

OPEN ITEM 2: Evaluate accessibility of the Mechanical ROS for radiological and environmental conditions.

Address dose and temperature items for the Mechanical ROS and non-MCR locations.

FAQ-HCVS-01I (Reference

14) will be used as guidance.*At 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , based on battery depletion, power supply will be swapped from the dedicated HCVS batteries to the FLEX DO to ensure power to the inverters.

The HCVS UPS transfer switch will be located in the Control Building corridor.

To access the transfer switch, operators will only be required to travel in the Control Building.

Radiological consequences resulting from the operation of the HCVS are not expected in the Control Building, as the HICVS will only be routed inside the Reactor Building.

In addition, the Control Building provides shielding.

OPEN ITEM 3: Determine the location of the dedicated HCVS battery transfer switch. (COMPLETE)

At >24 hours, installed nitrogen bottles will be valved-in to supplement the air accumulator supply for PC-AOV-237AV and PC-AOV-A032 as stated for the related time constraint item. Nitrogen bottles will be pre-staged and pre-connected in the Mechanical ROS. The Mechanical ROS will be evaluated for radiological and environmental conditions as stated in Open Item 2.OPEN ITEM 4: Determine the location of backup nitrogen bottles and evaluate the effects of radiological and temperature constraints on their deployment.

At >24 hours, actions to connect the UPS battery to a power supply will oeccur on the north side of the CNS Control Building and within the Control Building itself. The Control Building is located on the north side of the Reactor Building.

The locations for installation (and control) of the DO are therefore shielded from IICVS piping by the Reactor Building and is greater than 100' away from the piping and the stack. Although there is no radiological and temperature constraints associated with the connection of the UPS batteries to its backup power supply, there may be radiological and temperature constraints related to the deployment of the backup supply itself, such as the deployment of the FLEX DO dedicated to recharge the UPS battery.OPEN ITEMS5: Evaluate location of the portable DO for accessibility under SA HCVS use.Provide details on the vent characteristics.

Vent Size and Basis (EA 1 09 Section 1.2.1/INEI113-02 Section 4.1.1)What is the plants licensed power? Discuss any plans for possible increases in licensed power (e.g. MUR, EPU).CNS OlP CNS QIP ~~Page 14 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent What is the nominal diameter of the vent pipe in inches/Is the basis determined by venting at containment design pressure, Primary Containment Pressure Limit (PCPL), or some other criteria (e.g. anticipatory venting)?Vent Capacity (EA-13-109 Section 1.2.1/INEI 13-02 Section 4.1.1)Indicate any exceptions to the 1% decay heat removal criteria, including reasons for the exception.

Provide the heat capacity of the suppression pool in terms of time versus pressurization capacity, assuming suppression pool is the injection source.Vent Path and Discharge (CA 109 Section 1.1.4. 1.2.2 / NEI113-02 Section 4.1.3. 4.1.5 and Appendix FIG)Provides a description of Vent path, release path, and impact of vent path on other vent element items.Power and Pneumatic Supply' Sources (EA 1 09 Section 1.2.5 & 1.2.6/NEI 13-02 Section 4.2.3. 2.5. 4.2.2, Provide a discussion of electrical power requirements, including a description of dedicated 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months power supply from permanently installed sources. Include a similar discussion as above for the valve motive force requirements.

IIndicate the area in the plant from where the installed/dedicated power and pneumatic supply sources are coming.Indicate the areas where portable equipment will be staged after the 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months period, the dose fields in the area, and any shielding that would be necessary in that area. Any shielding that would be provided in those areas.Location of Control Panels EA 109 Section 1.1.1. 1.1.2,.1.1.3,.1.1.4,.1.24.4 1.2.5/NEIJ3-02 Section 4.1.3.4.22.2 4.2.3. 4.25.5 4.26.6 6.1.1 and Appendix FIG)Indicate the location of the panels, and the dose fields in the area during severe accidents and any shielding that would be required in the area. This can be a qualitative assessment based on criteria in NE1 13-02.Hydrogen (BA 109 Section 1.2.10. 1.2.11. 1.2.12/NEIJ3-02 Section 2.3.2.4. 4.1.1, 4.1.6.4.1.7.5.1.

&Appendix 1t)State which approach or combination of approaches the plant will take to address the control of flammable gases, clearly demarcating the segmaents of vent system to which an approach applies.Unintended Cross Flow of Vented Fluids (EA-13-109 Section 1.2.3, 1.2.12/NEI113-02 Section 4.1.2. 4.1.4, 4.1.6 and Appendix H)Provide a description to eliminate/minimize unintended cross flow of vented fluids with emphasis on interfacing ventilation systems (e.g. SGTS). What design featutres are being included to limit leakage through interfacing valves or Appendix I type testing features?Prevention of Inadvertent Actuation (EA-13-109 Section 1.2. 7/NE1 13-02 Section 4. 2.1)The HGCVS shalt include means to prevent inadvertent actuation.

Component Oualifications (EA-13-109 Section 2.1/INEI 13-02 Section 5.1. 5.3)State qualification criteria based on use of a combination of safety related and augmented quality dependent on the location, function and interconnected system requirements.

Monitoring of HCVS (Order Elements 1.1.4. 1.2.8. 1.2.9/NE1 13-02 4.1.3. 4.22.2 4.2.4. and Appendix FIG)Provide a description of instruments used to monitor I-C VS operation and effluent.

Power for an instrument will require the intrinsically safe equipment installed as part of the power sourcing.Component reliable and rugged performance (EA 109 Section 2.2/INEI 13-02 Section 5.2. 5.3)I-C VS components including instrumentation should be designed, as a minimum, to meet the seismic design CNS OlP CNS aiP ~~Page 15 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent requirements of the plant.Components including instrumentation that are not required to be seismically designed by the design basis of the plant should be designed for reliable and rugged performance that is capable of ensuring HICVS functionality following a seismic event. (reference ISG-JLD-201201 and JSG-JLD-2 012-O3 for seismic details.)The components including instrumentation external to a seismic category 1 (or equivalent building or enclosure should be designed to meet the external hazards that screen-in for the plant as defined in guidance NEI112-06 as endorsed by JLD-ISG-12-0J for Order EA-12-049.

Use of instruments and supporting components with known operating principles that are supplied by manufacturers with commercial quality assurance programs, such as 1S090 01. The procurement specif/ications shall include the seismic requirements and/or instrument design requirements, and speci4fy the need for coininercial design standards and testing under seismic loadings consistent with design basis values at the ins trument locations.

Demonstration of the seismic reliability of the instrumentation through methods that predict performance by analysis, qualification testing under simulated seismic conditions, a combination of testing and analysis, or the use of experience data. Guidance for these is based on sections 7, 8, 9, and 10 of lEEE Standard 344-2004, "IEEE Recommended Practice for Seismic Qualification of Class 1E Equipment for Nuclear Power Generating Stations," or a substantially similar industrial standard could be used.Demonstration that the instrumentation is substantially similar in design to instrumentation that has been previously tested to seismic loading levels in accordance with the plant design basis at the location where the instrument is to be installed (g-levels and frequency ranges). Such testing and analysis should be similar to that performed for the plant licensing basis.Vent Size and Basis: The HCVS wetwell path is designed for venting steanm/energy at a nominal capacity of 1% or greater of 2,419 MWt (which corresponds to the CLTP) at pressure of 56 psig. This pressure is the lower of the containment design pressure (56 psig) and the PCPL value (62.7 psig). The size of the wetwell portion of the HCVS goes from 20" to 24" until it combines with the HCVS piping which, will be sized at 12", which provides adequate capacity to meet or exceed the Order criteria.

There are no plans for increases on licensed power.Vent Capacity: There are no exceptions to the 1% decay heat removal capacity.

The 1% value at CNS assumes that the suppression pool pressure suppression capacity is sufficient to absorb the decay heat generated during the first 3 hours3.472222e-5 days 8.333333e-4 hours 4.960317e-6 weeks 1.1415e-6 months . The vent would then be able to prevent containment pressure from increasing above the containment design pressure.

As part of the detailed design, the duration of suppression pool decay heat absorption capability will be confirmed.

OPEN ITEM 6: Confirm suppression pool heat capacity.Vent Path and Discharge:

The HCVS vent path at CNS consists of a wetwell vent. The HCVS will use the existing THPV piping between the wetwell penetration X-205 and PCIV PC-AOV-237AV.

Penetration X-205 is a 20" piping penetration located at the top of the torus, midway between ring girders in a vent pipe bay. The piping enlarges to a 24" pipe right beyond the penetration.

This pipe contains two butterfly PCIVs, PC-MOV-233MV and PC-AOV-237AV.

CNS OIP Page 16 of 83 Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent Currently, further downstream, the 24" pipe changes to a 24" piping/thin-walled piping. This thin-walled piping has been evaluated (calculation NEDC 92-054) and determined to meet the design requirements of the HCVS, and a new 12" line will be tied into this 24" line. The new control valve that replaces PC-AOV-A032 (the venting valve) will be installed on the new 12" line in the torus room area. The pipe will then travel along the south wall of the Reactor Building, to the southwest corner room. The pipe will enter the corner room using a new penetration in the southwest diagonal wall. The pipe will then travel across the corner room to enter the southwest staircase "A2" below floor elevation 903'-6". Once in the staircase, the pipe will follow the underside of the staircase and penetrate the southwest corner of the stairwell landing (i.e., the first stairwell landing on the west wall above 903'-6"). The pipe will travel through the staircase all the way to the refueling floor (elevation 1001 '-0"). It will penetrate the 1001' concrete floor slab in the southwest corner of the stairwell landing, and it will exit the top of the stairwell concrete structure (9' above elevation 1001 ') on the refuel floor. The vent line will then follow the south wall to a structural beam. The vent line will then go vertically out to the Reactor Building roof for the release point. The effluent will exit out of the Reactor Building.Release Point: The release point will be located at an elevation of at least 1056', i.e., more than 3' above the top of Reactor Building parapet walls (1 052'-9") per NEI guidance contained in HCVS-FAQ-04, Revision 3 (Reference 17).Protection from rain and snow is provided by a weather cap secured in place by breakaway bolts. The stack design is a vertical release point above the Reactor Building root, in order to release the effluent directly up into the atmosphere.

The weather cap is designed to blow off such that anticipatory venting naturally removes the cap during venting operations.

Similarly, the check-valve is designed to open at a maximum of 2 psig for anticipatory venting. The weather cap repels birds, prevents ice formation, and protects the HCVS pipe from water and other debris. The weather cap, pipe size, and check valve satisfy security requirements.

_Drains and Water-lianmer Prevention:

Water hammer does not occur in the HCVS line during operation as a result of condensation of the steam, or during the opening/closing of the control valve PC-AOV-A032.

Additionally, the HCVS does not require a drainage system due to entrainment of condensation in the high velocity flow and the low amount of condensation produced during venting or accumulated after HCVS venting.Wind and Missile Protection:

The entire HCVS line, with the exception of the pipe section exiting the Reactor Building root, is located inside the Reactor Building, which is a Seismic Class I building.

The UPS system powering PC-MOV-233MV is located in the Reactor Building as well. The HCVS UPS system is located in the Control Building which is a Seismic Class I building.

Seismic Class I buildings provide adequate wind and missile protection.

lisummary, the location of the HCVS was evaluated against the guidance proposed in NEI HCVS-FAQ-04, Revision 3 (Reference

17) with respect to missile protection, distance of the release point to the nearest structures, potential for damage due to deflagration/detonation in effluent plume, and the release point distance and elevation relative to emergency filtration intake and exhaust pathways.i. The release point will be at least 3' above the roof and related structures of the building that it emanates from (such as roof parapets).

2. Missile protection evaluation is required for piping segnents outside of Seismic Class I structures.

CNS OIP CNS OIP ~~Page 17 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent This evaluation, referenced by NEI 13-02, Section 5.1.1.6.2, can utilize: NRC Regulation Guide 1.76, Revision I, Design-Basis Tornado And Tornado Missiles For Nuclear Power Plants, which limits automobile missile impact to "all altitudes less than 30 feet"; the plants current licensing bases; or other pertinent information.

An evaluation will show that smaller missiles are very unlikely to hit the pipe exhaust at this height.3. The ROS is the only structure located under the 25' horizontal limit. The radiological and environmental conditions at the ROS and the impact of vent operations on accessibility of the ROS will be evaluated as part of Open Item 2.4. No flammable or heat sensitive equipment is or will be located near the pipe exhaust.5. fIntakes are either located further than 100' horizontally and 20' vertically, or meet the 5:1I rule.Power and Pneumatic Supply Sources: Electrical Power Supply:.All electrical power required for operation of HCVS components (except PC-MOV-233MV), NCVS instrumentation, and indication in the MCR and at the Mechanical ROS will be routed through the HCVS UPS system. The HCVS UPS will consist of a bank of battery cells providing 1 20VDC powering an inverter, which supplies alternate HCVS 120 VAC power, and a 120VAC Distribution Panel. The battery of choice is a sealed cell (or voltage regulated lead acid) due to its minimal hydrogen generation.

The HCVS has no tie to the station batteries 125 DCA, 125 DCB, 250VDCA or 250VDCB. The only indicators at the UPS are the AC and DC voltmeters, used to monitor }{CVS battery power availability.

Note that PC-MO V-23 3MV will be powered by a separate alternate power supply. This alternate supply will consist of a UPS (charger, battery, and inverter) and transfer switch at or near MCC-RA. The transfer switch will provide proper separation of the safety-related control and power circuits for PC-MOV-233MV.

The UPS will provide 480 VAC three phase power for PC-MOV-233MV, and will be sized to provide three operating cycles of the valve during the 24-hour period before FLEX power or offsite power is restored.

See Sketch 1 of Attachment 3 for a 1-line sketch of the UPS systems (HCVS UPS and PC233MV UPS).If the station power is not restored after 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , power to the 1HCVS Distribution Panel will be provided directly by a FLEX DG (bypassing the UPS battery charger) or by recharging the UPS batteries with a FLEX DO. The transfer switch will be aligned to supply normal AC power to the battery charger during normal operation.

During the Beyond Design Basis event, cables will be connected to the receptacles installed on the transfer switch enclosure and connected to the cables from a FLEX DO.The UPS will be located at the far end of the Control Building corridor at the 903'-6" level. At this location, the UPS will be easily and readily accessible from the MCR (located in the Control Building at elevation 932'-6").This location was chosen based on the seismic class of the Control Building and being above the design basis flood level. The relative absence of safety-related equipment in that area is also a positive feature. Additionally, this location is in relatively close proximity to both the Control Room and anticipated connection points for FLEX power sources. The PC233MV UPS was sized to provide power for three opening/closing cycles of PC-MOV-233MV. The valve is expected to be open once and left open during venting operations.

Therefore, the current size of the PC233MV UPS provides enough power supplies for more than 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .CNS OIP CNS OIP ~~Page 18 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overali Integrated Plan (EA-1 3-109)Part 2: Boundary Conditions for Wet Well Vent Radiological consequences resulting from the operation of the HCVS are not expected in the Control Building, as the HCVS will only be routed inside the Reactor Building (in addition to the shielding the Control Building provides).

Heat loads seen during the severe accident, resulting from the undercooled containment, ELAP conditions, and operation of the equipment in the room where the HCVS UPS is located will be calculated as per Open Item 2. Equipment and instrumentation at the HCVS UPS is designed to withstand such conditions.

Pneumatic Power Supply: Pneumatic power is normally provided by the non-interruptible air system with backup nitrogen provided from installed nitrogen supply tanks. Following an ELAP event, the station air system is lost, and normal backup from installed nitrogen supply tanks is isolated.

Therefore, for the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , pneumatic force will be supplied from existing and newly installed air accumulator tanks. These accumulators will supply the required motive force to those IICVS valves needed to maintain flow through the HCVS effluent piping.1. The HCVS flow path valves are a 24" MOV, AC power to open and close, followed by a 24" AOV, air-to-open and spring-to-shut.

The vent control valve will be a 12" AOV with air-to-open and spring-to-shut.

Opening the AOVs requires energizing an AC powered SOV and providing motive air/gas, while opening the MOV requires AC power. Power to energize the SOVs will be provided by the HCVS UPS. Power to operate the MOV will be provided by a separate, PC233MV UPS. To prevent failure of the HCVS due to failure of the solenoid valves to actuate PC-AOV-237AV and PC-AOV-A032, shuttle valves will be installed to allow these AOVs to accept nitrogen from the Mechanical ROS. Actuation of PC-AOV-237AV and PC-AOV-AO32 via nitrogen through the associated shuttle valves will be performed from the Mechanical ROS. The HCVS UPS, the PC233MV UPS, and the AOV accumulators provide permanently installed power source and motive air/gas supply adequate for the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . Beyond the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , FLEX generators will be used to maintain battery power to the HCVS components.

The initial stored motive air!/gas will allow for B valve operating cycles for PC-AOV-A032 and one cycle of PC-AOV-237AV for the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . This is conservative in regards to the results contained in the September 2014 MAAP analysis to support the CNS FLEX strategy (Reference 44). In this analysis, strategies with the vent continuously open (no cycle), or with one cycle or two cycles only, are sufficient to maintain Torus pressure between 15 and 30 psia and the suppression pool water temperature below 240°F.2. An assessment of temperature and radiological conditions will be performed to ensure that operating personnel can safely access and operate controls at the ROS based on time constraints listed in Attachment 2A.3. All permanently installed HCVS equipment, including any connections required to supplement the HCVS operation during an ELAP (i.e., electric power, N 2/air) will be located in areas reasonably protected from defined hazards listed in Part 1 of this OIP.4. All valves required to open the flow path or valves that require manual operation to be closed to prevent diversion or cross-flow into other systems/units will be designed for remote manual operation following an ELAP, such that the primary means of valve manipulation does not rely on use of a hand wheel, reach-rod or similar means that requires close proximity to the valve (Reference 16, FAQ HCVS-03).

The remote manual operation of the valves will be performed from the Control Room. Only PC-AOV-237AV and PC-AOV-A032 can additionally be operated from the ROS if the associated solenoids fail. Accessibility of the ROS during the event will be evaluated for radiological and environmental conditions, and strategies such as the use of ice vests or shielding will be implemented if deemed necessary.

Any supplemental connections will be pre-engineered to minimize man-power resources and address environmental concerns.CNS OIP CNS QIP ~~Page 19 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Part 2: Boundary Conditions for Wet Well Vent Required portable equipment will be reasonably protected from screened in hazards listed in Part 1 of this OIP. A list of portable equipment can be found in Attachment

1.5. Access

to the locations described above will not require temporary ladders or scaffolding.

6. Following the initial 24-hour period, additional motive force will he supplied from nitrogen bottles that will be pre-staged and pre-connected at the Mechanical ROS. Additional nitrogen bottles will also be available on-site for re-supply of the Mechanical ROS.Location of Control Panels: The HCVS design allows initiating and then operating and monitoring the HCVS from the MCR and the ROS.The MCR location is protected from adverse natural phenomena and is the normal control point for Plant Emergency Response actions.The Mechanical ROS will be located as shown on Figure 1-1 on the exterior south wall of the Reactor Building, and will be several feet to the east of the current standby nitrogen injection station (and its barricaded door) just inside the security fence entrance to the transformer area. The Mechanical ROS will be a missile shielded structure.

A door will be needed in order to allow operator access and to move additional nitrogen bottles into the Mechanical ROS to supply pneumatic motive force beyond the initial 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months of the event. The exterior and interior walls forming the door entrance will be constructed in order to protect the equipment in the Mechanical ROS from tornado missiles.

Therefore, the door does not need to be designed for missile protection itself.[cf. OPEN ITEM 2: Evaluate accessibility of the Mechanical ROS for radiological and environmental conditions.

Address dose and temperature items for the Mechanical ROS and non-MCR locations.

FAQ HCVS-01I (Reference

14) will be used as guidance.]

As is required by EA-13-109, Section 1.2.11, the HCVS must be designed such that it is able to either provide assurance that oxygen cannot enter and mix with flammable gas in the HCVS (so as to form a combustible gas mixture), or it must be able to accommodate the dynamic loading resulting from a combustible gas detonation.

Several configurations are available which will support the former (e.g., purge, mechanical isolation from outside air, etc.) or the latter (design of potentially affected portions of the system to withstand a detonation relative to pipe stress and support structures).

Hydrogen control will be addressed using a check valve in the discharge pipe placed such that the remaining length of piping is less than the minimum mun-up distance required for a DDT to occur (NEI HCVS-WP-03, Reference 25). A new check valve will be installed on the 1001' floor (refueling floor) of the Reactor Building.The function of this valve is twofold: first, the function of the valve is to eliminate air ingress further down the pipe when the venting stops and the steam condenses; second, the function of the check valve is to bottle up the steam and hydrogen in the pipe volume below this valve and above the upstream control valve. The check valve will be designed for the temperature, pressure, and radiological conditions seen at its location.OPEN ITEM 7: Determine which approach or combination of approaches CNS will take to address the control of flammable gases, clearly demarcating the segments of vent system to which an approach applies. (COMPLETE)

CNS OlP CNS alP ~~Page 20 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent Unintended Cross Flow of Vented Fluids: The HCVS uses the Containment Purge System containment isolation valves for containment isolation.

The inboard valve (PC-MOV-233MV) is an AC motor driven MOV and the outboard valve (PC-AOV-237AV) is an AOV with an AC powered SOV, and can be operated from switches in the MCR. An AC motor must be energized to open the MOV. An AC SOy must be energized to allow the motive air to open the AOV. Although these valves are shared between the Containment Purge System and the HCVS, key-locked override switches are provided to each valve to allow operators to override the containment isolation signal. Specifically:

The Containment Purge System control circuit will be used during all "design basis" operating modes including all design basis transients and accidents.

Suppression Chamber InlOutboard Isolation Valves PC-MO V-1304MV and PC-MO V-1303MV are normally closed and meet the requirements of lOCFR50 Appendix J, Type C Testing.*Suppression Chamber Vacuum Relief Outboard Isolation Valves PC-i13CV and PC-14CV are normally closed check-valves that automatically open on a differential pressure of 0.5 psid across the valve to ensure that the 0xternal design pressure of the torus will not be exceeded.

The valve in its normally closed position provides outboard primary containment isolation.

The valves meet the requirements of 10OCFR5O Appendix J, Type C Testing. PC-AOV-243AV and PC-AOV-244AV, which are the Inboard Isolation Valves for Suppression Chamber Vacuum Relief, meet the requirements of 10CFR5O Appendix J, Type C Testing.*Vacuum breaker PC-3OCV is currently installed on the 10" TIZPV piping upstream of PC-AOV-A032 to prevent collapse of the 24" Torus Purge and Vent Supply thin wall pipe after a venting operation.

Since the 10" line is removed, this vacuum breaker is removed. Vacuum breaker PC-3OCV is not replaced in the HCVS. During an event which requires venting through the HCVS, PC-MOV-233MV and PC-AOV-237AV remain open. This allows the existing Suppression Chamber Relief System (PC-AOV-243AV and PC-AOV-244AV) to provide relief of vacuum conditions within the piping from the Torus to PC-AOV-AO32. Therefore, replacing the THPV vacuum breaker PC-3OCV is not necessary.

The Suppression Chamber Valve PC-AOV-235SAV, the Nitrogen Purge Supply Valve PC-AOV-23 9AV, and their support components will be replaced.

Replacement valves will be leak-tight and will meet the requirements of 1OCFR5O, Appendix J. The replacement components will be designed to the environmental and radiological conditions seen at the location during a severe accident requiring the use of the HCVS. Testing and maintenance will be performed to ensure that the valves remain leak-tight.

New local leak rate test connections will be added in order to individually test the leak-tightness of the new PC-AOV-235AV, PC-AOV-239AV, venting valve (replacing PC-AOV-A032), and vacuum breaker.*The HCVS vent path minimizes the number of auxiliary lines and interfacing ventilation systems. For example, the HCVS line will not interface with the SGT system or ERP. All auxiliary lines are currently, or will be, isolated with boundary valves meeting the requirements of 10OCFR5O Appendix J. Therefore, the risk of unintended cross flow of vented fluids will be minimized.

CNS is a single unit. As such, interconnection through the common plant stack is not applicable.

Pipe leakage to the Reactor Building and other buildings will be minimized:

CNS OIP Page 21. of 83 Revision2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent o Leak tightness of the vent pipe from PG-AOV-237AV to the exhaust will be tested in compliance with the requirements of USAS B31.l.O, 1967 Edition.o Since the HCVS piping will be designed and installed per USAS B31 .1.0, 1967 Edition, the HCVS piping will meet the Nondestructive Inspection and Examination requirements of power piping in USAS B31.1.O, 1967 Edition. This requires that all the pipe welds are visually inspected.

Vrevention of Inadvertent Actuation:

EOP/EPG operating procedures provide clear guidance that the HCVS is not to be used to defeat containment integrity during any design basis transients and accident.

In addition, the HCVS will be designed to provide features to prevent inadvertent actuation due to a design error, equipment malfunction, or operator error such that any credited CAP that would provide net positive suction head to the EGGS pumps will be available (inclusive of a DBLOGA). However, the EGGS pumps will not have normal power available because of the starting boundary conditions of an ELAI'. CNS credits GAP to maintain sufficient NPSH for EGGS Pumps (Gore Spray and RHR).'Therefore, it is essential to prevent inadvertent actuation of the HCVS to ensure that the CAP can be maintained.

At CNS, the features that prevent inadvertent actuation are two containment isolation valves in series powered from different divisions and key-lock switches.

With respect to the containment isolation valves, the inboard valve (PC-MOV-233MV) is an AC motor driven MOV fed from a Division ITAG power source, and the outboard valve (PG-AOV-237AV) is an AOV with an AC powered SOV fed from a Division II AC power source. Hence, the containment isolation valves meet the requirements for redundant and diverse power sources. Furthermore, these valves can be operated from key-locked switches in the MCR. Although these valves are shared between the Containment.Purge System and the HCVS, key-locked override switches are provided for each valve to allow operators to override the containment isolation signal. Specifically:

The Containment Purge System control circuit will be used during all "design basis' operating modes including all design basis transients and accidents.

The containment isolation signal will cause the valves to shut.*The HGVS control circuit will have a key-locked switch for each of the two in-series valves to address inadvertent operation.

Turning the switch to "open" will energize the control circuit opening the valve.Both valves will use AC power for opening for the HGVS function.

Also, separate control circuits including switches will be used for the two redundant valves to address single point vulnerabilities that may cause the flow path to inadvertently open.Procedures also provide clear guidance to not circumvent containment integrity by simultaneously opening torus and drywell vent valves during any design basis transient or accident.

In addition, the HGCVS will be designed to provide features to prevent inadvertent actuation due to a design error, equipment malfunction, or operator error.Component Qualifications:

The HGVS components downstream of the second containment isolation valve, and components that interface with the HGVS, are routed in seismically qualified structures.

The Mechanical ROS5 will be a seismically qualified structure.

HCVS components that directly interface with the pressure boundary will be considered safety-related, as the existing system is safety-related.

The containment system limits the leakage or release of radioactive materials to the enviromnent to prevent offsite exposures from exceeding the guidelines of lOGFR100.

During normal or design basis operations, this means serving as a pressure boundary to prevent release of radioactive material.CNS OIP Page 22 of 83 Revision Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent Likewise, any electrical or controls component which interfaces with Class IE power sources will be considered safety-related up to and including appropriate isolation devices such as fuses or breakers, as their failure could adversely impact containment isolation and/or a safety-related power source. The HCVS UPS and PC233MV UPS are considered Balance of Plant. Where the UPS circuits interface with safety-related circuits, the appropriate separation will be provided by transfer switches, disconnects, or interposing relays between safety and non-safety-related circuits.

The remaining components will be considered Augmented Quality. Newly installed piping and valves will be seismically qualified to handle the forces associated with the SME back to their isolation boundaries.

Electrical and controls components will be seismically qualified and will include the ability to handle harsh environmental conditions (although they will not be considered part of the site EQ program).UCVS instrumentation performance (e.g., accuracy and precision) need not exceed that of similar plant installed equipment.

Addittionally, radiation monitoring instrumentation accuracy and range will be sufficient to confirm flow of radionuclides through the HCVS.The HCVS instruments, including valve position indication, process instrumentation, radiation monitoring, and su~pport system monitoring, will be qualified by using one or more of the three methods described in the ISG, which includes: 1. Purchase of instruments and supporting components with known operating principles from manufacturers with commercial quality assurance programs (e.g., IS09001) where the procurement specifications include the applicable seismic requirements, design requirements, and applicable testing.2. Demonstration of seismic reliability via methods that predict performance described in IEEE 344-2004.3. Demonstration that instrumentation is substantially similar to the design o f instrumentation previously qualified.

Table 2-2, Qualification Method of HCVS instrumentation Instrument Qualification Method*HCVS Process Temperature IS09001 / IEEE 344-2004 / Demonstration HCVS Process Pressure 1S09001 / IEEE 344-2004 / Demonstration HZCVS Process Radiation Monitor 1509001 / IEEE 344-2004 / Demonstration HCVS Process Valve Position 1S09001 / IEEE 344-2004 / Demonstration HZCVS Pneumatic Supply Pressure 1s09001 / IEEE 344-2004 / Demonstration HCVS Electrical Power Supply Availability 1s09001 / IEEE 344-2004 / Demonstration Existing HCVS Containment Pressure 1S09001 / IEEE 344-2004 / Demonstration Existing Suppression Pool Level 1S09001 / IEEE 344-2004 / Demonstration Existing Suppression Pool Temperature IS09001 / IEEE 344-2004 / Demonstration Nitrogen Bottles Pressure 1S09001 / IEEE 344-2004 / Demonstration

The specific qualification method used for each required HzCVS instrument will be reported in future 6 month status reports.CNS OIP Page 23 of 83 Revision Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Pian (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent OPEN ITEM 8: Identify qualification method used for HCVS instruments.

The instrumentation is listed in Table 2-4 of the OIlP.Monitoring of HCVS~The CNS wetwell uCVS will be capable of being manually operated during sustained operations from a control panel located in the MCR and will meet the requirements of Order element 1.2.4. The MCR is a readily accessible location with no further evaluation required.

Control Room dose associated with HCVS operation conforms to GDC 19/Alternate Source Term. Additionally, to meet the intent for a secondary control location of Section 1.2.5 of the Order, a readily accessible ROS will also be incorporated into the HCVS design as described in NEI 13-02, Section 4.2.2.1.2.1.

The controls and indications at the ROS location will be accessible and functional under a range of plant conditions, including severe accident conditions with due consideration to source term and dose impact on operator exposure, FLAP, and inadequate containment cooling. An evaluation will be performed to determine accessibility to the location, habitability, staffing sufficiency, and communication capability with vent-use decision makers.OPEN ITEM 9: Evaluate HCVS monitoring location for accessibility, habitability, staffing sufficiency, and communication capability with vent-use decision makers.The wetwell HCVS will include means to monitor the status of the vent system in both the MCR and the ROS.Included in the current design of the THPV are control switches in the MCR with valve position indication (Reference 34). The existing THPV controls currently meet the environmental and seismic requirements of the Order for the plant severe accident and will be upgraded to address ELAP. At the ROS, a control panel will be included.

Monitoring the status of the vent line will be made possible with indications of the pressure in the accumulators IA-ACC-237AV and IA-ACC-A032, and a position indicator of PC-AOV-AO32 position.The ability to open/close these valves multiple times during the event's first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months will be provided by air accumulator tanks and two UPS systems (i.e., the HCVS UPS and PC233MV UPS) providing a backup battery power source. Beyond the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , the ability to maintain these valves open or closed will be provided with replaceable nitrogen bottles and FLEX generators.

The wetwell HCVS will include indications for vent pipe pressure (already available in the MCR), temperature (to be installed), and effluent radiation levels (already available in the MCR) at the MCR. Other important information on the status of supporting systems, such as power source status (to be installed) and pneumatic supply pressure (already available in the MCR for PC-AOV-AO32 but will be replaced with the valve replacement, and to be installed for PC-AOV-237AV), will also be included in the design and located to support HCVS operation.

The wetwellI-HCVS includes existing containment pressure and wetwell level indication in the MCR to monitor vent operation.

This monitoring instrumentation provides the indication from the MCR as per Requirement 1.2.4 and will be designed for sustained operation during an ELAP event.Table 2-3 summarizes the changes to the monitoring and control of the HCVS to meet the Order requirements and industry recommendations.

CNS OIP CNS OIP ~~Page 24 of 83 Rvso Revision 2 CoPert N:Bucleary SttonHadenediontainment Ventin Sysemt Ovberall, ICSMniteorated Pand Contro Change)Part 2: Boundary Conditions for Wet Well Vent Table 2-3, HCVS Monitoring and Control Changes NRC Requirements

&Industry Recommendations Existing I&C Change Order Requirement 1.2.4: The HCVS shall be designed to be manually operated during sustained operations from a control panel located in the MCR or a remote but readily accessible location.The primary controlling location of the existing TIIPV is the MCR. PCIVs valves can be manually operated from the MCR using key-locked override switches on Panel P2 and open/close switches on Vertical Board H- (PC-SW-CS (233AV) and PC-SW-CS (237AV)).AOV-A032 can be controlled from Panel P2 using key-locked switches.The primary controlling location of the HCVS is the MCR. During a severe accident, controls will be powered from a HCVS-dedieated UPS. PC-MOV-233MV will be powered from a separate alternate power supply (PC233MV UPS). The supply of pneumatic motive force after 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months will be performed from the Mechanical ROS.Order Requirement 1.2.5: The HCVS shall, in addition to the requirements of 1.2.4, be capable of manual operation (e.g., reach-rod with hand wheel or manual operation of pnentmatic supply valves from a shielded location), which is accessible to plant operators during sustained operations.

N/A The installation of a HCVS dedicated source of power ensures operation of the HCVS from the MCR. The supply of pneumatic motive force after 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months will be operated from the Mechanical ROS. In case the SOV of PC-AOV-237AV and/or PC-AOV-A032 fails, shuttle valves will allow actuation of the valves from the Mechanical ROS with pneumatic motive force.CNS OIP CNS alp ~~Page 25 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent Order Requirement 1.2.8: The HCVS shall include means to monitor the status of the vent system (e.g., valve position indication) from the control panel required by 1.2.4. The monitoring system shall be designed for sustained operation during an extended loss of AC power.HCVS valve position indication should be available at the primary controlling location. (NET 13-02, 4.2 .2.1 .5)The position of the following valves is indicated in the MCR: MOV-233MV, AOV-237AV, AOV-A032.PC-AOV-A032 will be replaced.

The circuit indicating position lights for PC-AOV-A032 on MCR Panel P2 will be modified accordingly to indicate the position of the new control AOV.An effluent pressure transmitter will be added to the line in the Torus Room to measure the effluent pressure and confirm the status of venting operations.

Order Requirement 1.2.9: The HCVS shall include a means to monitor the effluent discharge for radioactivity that may be released from operation of the HICVS.The monitoring system shall provide indication from the control panel required by 1.2.4 and shall be designed for sustained operation during an extended loss of AC power.Currently, RMA-RE-.27 measures radiation doses in the THPV. Indications are provided on MCR Panel 9-11.The existing radiation monitor is located near the section of the THPV line which will be demolished.

A new radiation monitor will be installed in the same area (Torus Room).The indication on Panel 9-11 will be modified to indicate the doses recorded on the new radiation monitor.HCVS valve position indicators should be capable of operating under conitinsexisting at the valve locations.(NEI 13-02, 4.2.2.1.6)

N/A Refer to Part 2, "Component Qualifications." CNS OIP CNS OIP ~~Page 26 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent HCVS valve position indicators and indications should be powered from sources that will be available during the appropriate mission time of the HCVS system.(NET 13-02, 4.2.2.1.7)

HCVS system should include indications of effluenlt temperature.

Permanently installed gauges that are at, or nearby, the HCVS control panel is an acceptable method to address this item.(NET 13-02, 4.2.2.1.8)(also see Order Requirement 1.2.8)N/A The position lights for the MOV will only be on when the MOV is energized from its temporary power supply.Once the valve is positioned open and the power supply is secured, the lights will be off.Position lights for PC-AOV-237AV and the new control valve (on MCR Vertical Board H) will be powered from the UPS.There is currently no existing instrumentation to monitor effluent temperature.

An effluent temperature monitor will be installed in the new pipe path on the refueling floor. Effluent temperature indication will be provided in the MCR.The HICVS system should include indications for the Containment Pressure and Wetwell level for deternination of vent operation.

Use of existing control room indications is adequate and these instruments do not need to be powered by the H-C VS battery system.(NET 13-02 4.2.2.1.9)(also see Order Requirement 1.2.8)The following parameters are already recorded in the MCR: Drywell Pressure on PC-PT-512A, -B; PC-PT-4A1, -4B2 Torus Pressure on PC-PT-30A, -30B Suppression Pool Level on PC-DPT-3A1, -3B 1 Although not required, these instruments and their indicators will be powered from the UPS to provide sustained indication during an FLAP.CNS OIP CNS QIP ~~Page 27 of 83 Rvso Revision 2 Cooper Nuciear Station Hardened Containment Venting System Overail Integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent Other important information includes the status of supporting systems, suhel as availability of electrical power and pneumatic supply pressure.(NEI 13-02, 4.2.4.1.3)

N/A Voltmeters (AC and DC) will be installed at the HCVS UPS to monitor the power availability of the HCVS dedicated battery.Pneumatic supply pressure will be monitored as follows: Local nitrogen bottle pressure gauges will be installed on each back-up pre-installed nitrogen bottle to monitor their availability.

Indication will only be available locally (at the bottle).The accumulators of AOV-237AV and the new control valve will be equipped with pressure monitors.

Indications of these pressures will be available at both the MCR and the Mechanical ROS.Table 2-4 below summarizes the locations (in the MCR, at the ROS, controls (I&C) for HCVS operation.

or at the UPS) of the instrumentation and Table 2-4, Summary of HCVS I&C Components and Indication oatio MCR IICVS Mechanical ROS ICUps PC1V controls Existing key-locked overlide switches None None, except piping to on Panel P2 and open/close switches on supply nitrogen to the Vertical Board H (PC-S W-CS(233AV) new shuffle valve for and PC-S W-CS(237AV)).

PC-AOV-237AV.

Powered from HCVS UPS.PCIV position Existing indicating lights on VBD H None None indicators Powered from HCVS UPS.Control valve controls PC-AOV-A032 key-locked switch on Panel P2 to be replaced, as A032 will be replaced.Powered from HCVS UPS.None None, except piping to supply nitrogen to the new shuttle valve for PC-AOV-A032.

Control valve position indication PC-AOV-A032 position indication (light on Panel P2) to be replaced.Powered from HCVS UPS.None New install.Powered from HCVS UPS.CNS OIP CNS QIP ~~Page 28 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Part 2: Boundary Conditions for Wet Well Vent Containment (DW and WW)pressure transmitters Existing Drywell Pressure from PC-PT-512A, -B; PC-PT-4A1, -4B32;Torus Pressure on IPC-PT-30A, -30B;None None Recorded on Panels 9-3 or 9-4.Powered from HCVS UPS.Suppression Existing on PC-DPT-3A1, -3B I. None None Pool Level Powered from 1HCVS UPS.Effluent New install. None None Temperature Powered from HCVS UPS.Monitor Effluent RMA-RE-27 indication on Panel 9-1l None None Radiation to be replaced.Monitor Powered from HCVS LIPS.Effluent PC-PS-20 to be replaced by a pressure None None Pressure transmitter.

Monitor Powered from NCVS UIPS.Accumulator IA-PS-3 is replaced by a pressure None New install.pressure transmitter.

A new pressure transmitter Accumulator pressure monitors is added to the AOV-237AV for valves PC-AOV-accumulators (in order to know when 237AV and PC-AOV-to use the Mechanical ROS). Powered A032 to be indicated.

from HCVS UPS.Pneumatic None (located at the Mechanical ROS). None New install -not motive force powered from UPS controls for (mechanical system), AOVs (manual normally not needed ball valves) before 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .Nitrogen bottle None (located at the Mechanical ROS). None New -not powered availability from UPS (analog (mechanical system), pressure normally not needed gauges) before 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .UIPS Power None (located at the H{CVS UPS). New None availability install status KPower transfer switch for IICVS UPS None (Transfer switch located at the HCVS UPS).New install None CN50IP CNS OIP ~~Page 29 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Part 2: Boundary Conditions for Wet Well Vent Power transfer None (located at the PC233MV UIPS New None switch for which is at, or near, MCC-RA). install; at PC233MV UPS or near MCC-RA in Reactor Building RPV Pressure Currently available with RFC-PI-90A, None None B, C.Suppression Existing PC-TE-lA to -I.H and -2A to -None None Pool 2H1. Recorded on PC-TR-24 and PC-Temperature TR-25 in MCR Vertical Board 3.Powered from HCVS UPS.Component reliable and rupeed performance:

The H-CVS downstream of the second containment isolation valve, including piping and supports, electrical power supply, valve actuator pneumatic supply, and instrumentation (local and remote) components, will be designed/analyzed to conform to the requirements consistent with the applicable design codes (e.g., Non-safety, Cat 1, SS and 300# ASME or B3 1. 1, NEMA 4, etc.) for the plant and to ensure functionality following a design basis earthquake.

A TH-PV system was originally installed to satisfy the requirements of Generic Letter 89-16. The modifications associated with the THPV system were performed under the provisions of 1OCFR5O.59, and thus the CNS THPV was designed, analyzed, and implemented consistent with the design basis of the plant. In addition, the THPV section upstream of the rupture disk was designed and installed per USAS B3 1.1.0 -1967 Edition, as explained in DC 9 1-041 (Reference 34). Therefore, this code will be used for piping design and installation.

HzCVS piping located downstream of the PC-AOV-237AV will be classified for Seismic TI/I requirements.

The current design will be evaluated to confirm that the existing system, coupled with the new HCVS line, will meet the requirements of Order BA-i13-109 and remain functional following a severe accident.Additional modifications required to meet the Order will be reliably functional at the temperature, pressure, and radiation levels consistent with the vent pipe conditions for sustained operations.

The instrumentation/power supplies/cables/connections (components) will be qualified for temperature, pressure, radiation level, total integrated dose radiation for the Effluent Vent Pipe, and HCVS ROS location.Conduit design will be installed to Seismic Class I criteria.

Both existing and new barriers will be used to provide a level of protection from missiles when equipment is located outside of seismically qualified structures.

Augmented quality requirements, will be applied to the components installed in response to this Order.If the instruments are purchased as commercial-grade equipment, they will be qualified to operate under severe accident environment as required by NRC Order BA-i13-109 and the guidance of NET 13-02. The equipment will be qualified seismically (IEEE 344), enviromnmentally (IEEE 323), and EMIC (per RO 1.180). These qualifications will be bounding conditions for CNS.CNS alP Page 30 of 83 Revision v Cooper Nuciear Station Hardened Containment Venting System Overail Integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent For the instruments required after a potential seismic event, the following methods will be used to verify that the design and installation is reliable / rugged and thus capable of ensuring H-CVS functionality following a seismic event. Applicable instruments are rated by the manufacturer (or otherwise tested) for seismic impact at levels commensurate with those of postulated severe accident event conditions in the area of instrument component use using one or more of the following methods:* demonstration of seismic motion will be consistent with that of existing design basis loads at the installed location;* substantial history of operational reliability in environments with significant vibration with a design envelope inclusive of the effects of seismic motion imparted to the instruments proposed at the location;*adequacy of seismic design and installation is demonstrated based on the guidance in Sections 7, 8, 9, and 10 of IEEE Standard 344-2004, IEEE Recommended Practice for Seismic Qualification of Class lE Equipment for Nuclear Power Generating Stations, (Reference

27) or a substantially similar industrial standard;* demonstration that proposed devices are substantially similar in design to models that have been previously tested for seismic effects in excess of the plant design basis at the location where the instrument is to be installed (g-levels and frequency ranges); or* seism~ic qualification using seismic motion consistent with that of existing design basis loading at the installation location.CNS OIP CNS OIP ~~Page 31 of 83 Rvso Revision 2 Cooper Nuciear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Part 2: Boundary Conditions for Wet Well Vent Part 2 Boundary Conditions for WW Vent: BDBEE Venting Determine venting capability for BDBiEE Venting, such as may be used in an ELAP scenario to mitigate core damage.Ref: EA-13-109 Section 1.1.4 / NET 13-02 Section 2.2 First 24 Hour Coping Detail Provide a general description of the venting actions for first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months using installed equipment including station mnodifications that are proposed.Ret: EA-13-109 Section 1.2.6 / NET 13-02 Section 2.5, 4.2.2 The operation of the IICVS will be designed to minimize the reliance on operator actions for response to an ELM'and BDBEE hazards identified in Part 1 of this OIP'. Immediate operator actions can be completed by operators from the MCR, except the transfer of power from Division I AC power to the PC233MV UPS, which will be performed at or near the MCC-RA in the Reactor Building.

If needed, supply of nitrogen to the AOVs' shuttle valves could be completed from the ROS. Actions will include remote-manual initiation, except the action of transferring MOV-233MV power. The operator actions required to open a vent path are as described in Table 2-1.Remote-manual is defined in this report as a non-automatic power operation of a component and does not require the operator to be at or in close proximity to the component.

No other operator actions are required to initiate venting under the guiding procedural protocol.The HCVS will be designed to allow initiation, control, and monitoring of venting from the MCR. Monitoring of the pneumatic supplies for the AOVs, monitoring of the position of the vent control valve, and control of AOVs PC-AOV-237AV and PC-AOV-A032 will also be available at the Mechanical ROS as part of the response to this Order. Both locations minimize plant operators' exposure to adverse temperature and radiological conditions and are protected from hazards assumed in Part 1 of this OIP.This scenario credits anticipatory venting at T=S hours and anticipates cycling of the control valve PC-AOV-A032.

Therefore, PCLVs PC-MOV-233MV and PC-AOV-237AV are expected to be opened only once and left open during the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months of mitigation.

Valve PC-AOV-237AV currently has two accumulators which provide sufficient back up air to operate the valve once and compensate for assumed leakage for 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . Valve PC-AOV-A032 will be cycled to control anticipatory venting. The new accumulator that will support operation of the new PC-AOV-A032 will be sized for eight valve cycles. As per industry white paper IICVS-WP-02 "Sequences for HCVS Design and Method for Determining Radiological Dose from HCVS Piping" (Reference 24), a generic number of 8 wetwell cycles or 12 drywell cycles within the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months was deemed reasonable.

Sizing the accumulator for 8 venting cycles is conservative in regards to the results contained in the September 2014 MAAP analysis to support the Cooper FLEX strategy (Reference 44). In this analysis, strategies with the vent continuously open (no cycle), or with one cycle or two cycles only, are sufficient to maintain Torus pressure between 15 and 30 psia and the suppression pool water temperature below 240 0 F. The detailed design of CNS HCVS will determine the final number of required valve cycles for the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months and the size of the initial stored motive air/gas that is required to support the number of valve cycles.OPEN ITEM 10: Determine the number of required valve cycles during the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . Size the electrical and pneumatic supplies accordingly.

CNS alP Page 32 ofS83 Revision 2 v Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent Part 2 Boundary Conditions for WW Vent: BDBEE Venting Permanently installed power and motive air/gas capability will be available to support operation and monitoring of the HCVS for 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .System control: i. Active: Control valves and/or PCJVs are operated in accordance with EOPs/SOPs to control containment pressure.

Controlled venting will be permitted in the revised EP~s and associated implementing EOPs. Anticipatory venting will be permitted, and the vent line will be kept open (or cycled) until 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months in the event. A key-lock switch permissive circuit without any automatic controls will allow the containment isolation valves to be opened regardless of existing containment isolation signals.ii. Passive: Inadvertent actuation protection is provided by the current circuitry associated with the containment isolation valves used to operate the HCVS. The containment isolation valves can be opened with key-lock switches in the MCR, as directed by applicable procedures.

Greater Than 24 Hour Coping Detail Provide a general description of the venting actions for greater than 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months using portable and installed equipment including station modifjications that are proposed Ref: EA-13-109 Section 1.2.4, 1.2.8 1 NEI 13-02 Section 4.2.2 After 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , available personnel will be able to connect supplemental motive air/gas to the HZCVS. Connections for supplementing electrical power and motive air/gas required for IICVS will be located in accessible areas with reasonable protection per NET 12-06 that minimize personnel exposure to adverse conditions for HCVS initiation and operation.

Connections will be pre-engineered quick disconnects to minimize manpower resources.

If the station power is not restored after 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , power to the HCVS Distribution Panel will be provided directly by a FLEX DG (bypassing the UPS battery charger) or by recharging the UPS batteries with a FLEX DGI. The transfer switch will be aligned to supply normal AC power to the battery charger during normal operation.

During the Beyond Design Basis event, cables will be connected to the receptacles installed on the transfer switch enclosure and connected to the cables from a FLEX DGI.Pneumatic supplies, in the form of portable nitrogen bottles, will be available for connection to provide motive gas to the HCVS.These actions provide long term support for HCVS operation for the period beyond 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months to 7 days (sustained operationa time period) because on-site and off-site personnel and resources will have access to the unit to provide needed action and supplies.Details Provide a brief description of Procedures

/ Guidelines:

Confirm that procedure/guidance exists or will be developed to support implementation.

NET 13-02 §6.1.2 CNS OIP CNS OIP ~~Page 33 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent Part 2 Boundary Conditions for WW/ Vent: BDBEE Venting Primary Containment Control Flowchart exists to direct operations in protection and control of containment integrity, including use of the existing Hardened Vent System. Other site procedures for venting containment using the HCVS include: EOP 5.8.18, Primary Containment Venting for PCPL, PSP, or Primary Containment Flooding (Reference 39); EOP 5.8.21, PC Venting and Hydrogen Control (Less than Combustible Limits)(Reference 35); EOP 5.8.22, PC Venting and Hydrogen Control (Greater than Combustible Limits) (Reference 36);Emergency Procedure 5.3ALT-STRATEGY, Alternate Core Cooling Mitigating Strategies (Reference 3'?).Identify modifications:

List modijfications and describe how they support the HCVS Actions.EA-1 2-049 Modifications:

o Upgrade power supply and indicators for torus level.* New connections to the FLEX DG may be required.EA-l 3-109 Modifications:

A modification will be required to remove the existing 10" THPV line from the 24" thin-walled pipe to the SGT system connection.

This modification will include removal of PC-AOV-A032, vacuum breaker PC-30CV, the pressure switch PC-PS-20, and the radiation monitor RMA-RiE-27.

A modification will be required to cap the existing THLPV connection at the SGT system. This cap will provide isolation of the SGT.* A modification will be required to remove the existing PC-AOV-235AV, PC-AOV-239AV, and support components, and install new valves and components capable of being qualified to l0CFR50 Appendix J.* A modification will be required to install the new 12" HCVS line from the upgraded 10 gauge thin-walled pipe to the top of the Reactor Building.

The modification will include tasks such as anchoring the new line, and drilling new penetrations.

A modification will be required to add pneumatic supply piping to provide nitrogen to the new shuttle valves from the Mechanical ROS, for PC-AOV-237AV and the new PC-AOV-A032.

A modification will be required to install a larger accumulator for the venting valve (PC-AOV-A032) to accomnmodate 8 venting cycles.* A modification will be required to install nitrogen bottles to provide pneumatic supply after 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .* A modification will be required to install a dedicated battery, charger, and UPS system (i.e., the HCVS UPS) to maintain power for the HCVS for 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months following the ELMP event.* A modification will be required to provide power at the MCC-RA for PC-MO V-233MV, by installing the PC233MV UPS.* A modification will be required to route cables from UPS to the equipment and instrumentation it supplies.* A modification will be required to install and build a missile-shielded ROS.* A modification may be required to ensure accessibility and habitability of the ROS during a BDBEE without core damage.o A modification will be required to install an HCVS Rad Monitor and power supply.* A modification will be required for installation of required HCVS instrumentation and controls in the MCR, such as indication of pneumatic supply availability, effluent temperature, and accumulator pressure.* Modifications may be needed to add connection points and valves to the HCVS to facilitate Appendix J type testing of the boundary valves.* Additional modifications may be required to system isolation valves, and existing HCVS piping.CNS OIP Page 34 of 83 Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent Part 2 Boundary Conditions for WW Vent: BDBEE Venting Key Venting Parameters:

List instrumentation credited for this venting actions. Clearly indicate which of those already exist in the plant and what others will be newly installed (to comply with the vent order).hnitiation1, operation and monitoring of the HCVS venting will rely on the following key parameters and indicators:

Table 2-5 Key Parameter Component Identifier Indication Location HCVS Effluent temperature PC-TT-.520 MCR HCVS Pneumatic supply IA-PS-3 to be replaced MCR (Annunciator P-2/C-2 pressure with pressure point 4992) / ROS (add to ROS)transmitter.

New pressure transmitter to be added to PC-AOV-237AV accumulators.

HCVS valve position indication Limit switch MCR / ROS (add to ROS)HCVS system pressure Pressure switch PC-PS- MCR (Annunciator P-2/B-2 indication 20 to be replaced.

point 4991)!/ ROS (add to ROS)HCVS electrical power supply TBD HCVS UPS availability (voltmeter)

HCVS process radiation monitor RMP-RE-520 MCR (Panel 9-1 1 and Annunciator P-2/A-2 on Panel P2) / ROS (add to ROS)Initiation and operation of the H{CVS system will rely on several existing MCR key parameters and indicators which are qualified or evaluated to the existing plant design (Reference 11, NET 13-02 Section 4.2.2.1.9):

Table 2-6 Key Parameter Component Identifier Indication Location Drywell pressure Transmitter PC-PT-5 12A (-5 to 70 psig)recorded on PC-LRPR-1A CH6 MCR Panel 9-3 Transmitter PC-PT-5 12B (-5 to 70 psig) MCR Panel 9-4 recorded on PC-LRPR-1B CH6 Transmitter PC-PT-4A1 (0 to 250psig) MCR Panel 9-3 recorded on PC-LRPR-lA CH3 Transmitter PC-PT-4B2 (0 to 250psig)recorded on PC-LRPR-1B CH3 MCR Panel 9-4 CNS OIP CNS alp ~~Page 35 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Part 2: Boundary Conditions for Wet Well Vent Part 2 Boundary Conditions for WW Vent: BDBEE Venting Torus pressure Transmitter PC-PT-30A

(-5 to 70 psig)recorded on PC-LRPR-1A CH5 MCR Panel 9-3 Transmitter PC-PT-30B

(-5 to 70 psig)recorded on PC-LRPR-1 A CH5 MCR Panel 9-4 Torus water Elements PC-TE-1A through 1H1 (0 to MCR Annunciator window J-temperature 250E) recorded on PC-TR-24, -25 1/A-1, J-lIA-2 Elements PC-TE-2A through 211 (0 to MCR Annunciator window J-250F), recorded on PC-TR-24, -25 l/A-l, J-1/A-2 Torus level Transmitter PC-DPT-3A1 MCR Panel 9-3 [PC-LRPR-IA]

Transmitter PC-DPT-3B2 MCR Panel 9-4 [PC-LRLPR-1B]

Reactor pressure RLFC-PI-90A, B and C (0 to 1200 psig) MCR Panel 9-5 HCVS Process RMA-RE-27 recorded on RMA-RA-27 MCR Panel 9-11 and Radiation to be replaced.

Annunciator P-2/A-2 on Panel Monitor P2 HCVS system Pressure switch PC-PS-20 to be replaced.

MCR (Annunciator P-2/B-2 pressure point 4991)indication HC VS IA-PS-3 to be replaced with pressure MCR (Annunciator P-2/C-2 pneumatic transmitter, point 4992)supply pressure New pressure transmitter to be added to PC-AOV-237AV accumulators.

HCVS valve Limit switch (for PC-MOV-233MV)

Indicating lights in MCR position (Vertical Panel 9-3) Vertical indication Board HI HCVS valve Limit switch (for PC-AOV-237AV)

Indicating lights in MCR position (Vertical Panel H)indication HCVS valve Limit switch (for PC-AOV-A032) to be Indicating lights in MCR (Panel position replaced.

P2)'indication HCVS indications for HCVS valve position indication, HCVS pneumatic supply pressure, HCVS effluent temperature, and HCVS system pressure will be installed in the MCR to comply with Order EA-13-1i09.

Notes: None.CNS OtP CNS OW ~~Page 136 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-i13-1 09)Part 2: Boundary Conditions for Wet Well Vent Part 2 Boundary Conditions for WW Vent: Severe Accident Venting Determine venting capability for Severe Accident Venting, such as may be used in an ELAP scenario to mitigate core damage.Ret: EA-13-109 Section 1.2.10 / NET 13-02 Section 2.3 First 24 Hour Coping Detail Provide a general description of the venting actions for first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months using installed equipment including station modijfications that are proposed.Ret: EA-13-109 Section 1.2.6 / NET 13-02 Section 2.5, 4.2.2 The operation of the HCVS will be designed to minimize the reliance on operator actions for response to an ELAP and severe accident events. Severe accident event assumes that specific core cooling actions from the FLEX strategies identified in the response to Order EA-1 2-049 were not successfully initiated.

Access to the Reactor Building will be restricted as determined by the RPV water level and core damage conditions.

Immediate actions will be completed by operators in the MCR, except the transfer of power from Division I AC power to the PC233MV UPS, which will be performed at or near the MCC-RA in the Reactor Building.

Since this action will be performed at the very beginning of the event, water will still be covering the core and no additional radiological conditions will be present at the location.

If needed, supply of nitrogen to the AOVs' shuttle valves could be completed from the HCVS ROS. Actions will include remote-manual actions, except the action of transferring MOV-23 3MV power. The operator actions required to open a vent path were previously listed in the BDBEE Venting Part 2 section of this OIP (Table 2-1).As stated in the section on BDBEE Venting, the HCVS will be designed to allow initiation, control, and monitoring of venting from the MCR and will be capable of operation from an ROS to be installed as part of the response to this Order. Both locations minimize plant operators' exposure to adverse temperature and radiological conditions and are protected from hazards assumed in Part 1 of this 0IP. Travel pathways will be reviewed for dose and temperature, and alternate routes may need to be considered to minimize operator exposure to harsh environmental conditions.

Permanently installed power and motive air/gas capable will be available to support operation and monitoring of the IZCVS for 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . Specifics are the same as for BDBEE Venting Part 2.System control: SActive: Same as for BDBEE Venting Part 2.i i Passive: Same as for BDBEE Venting Part 2.Details Provide a general description of the venting actions for greater than 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months using portable and installed Iequipment including station modifications that are proposed.Ref: EA-13-109 Section 1.2.4, 1.2.8 / NET 13-02 Section 4.2.2 CNS OIP CNS QIP ~~Page 37 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Part 2: Boundary Conditions for Wet Well Vent Part 2 Boundary Conditions for WW Vent: Severe Accident Venting Specifics are the same as for BDBEE Venting Part 2 except:* A connection point will be provided on the AC side of the battery charger in the HCVS UPS to accept input from a FLEX DG to relieve the battery after the initial 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months period.* The location and refueling actions for the FLEX OG and replacement nitrogen bottles will be evaluated for SA environmental conditions resulting from the proposed damaged Reactor Core and resultant HCVS vent pathway.OPEN ITEM 11: Evaluate the impact of SA environmental conditions for post-24 hour actions supporting the implementation of power and pneumatic supplies.These actions provide long term support for HCVS operation for the period beyond 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months to 7 days (sustained operation time period) because on-site and off-site personnel and resources will have access to the unit to provide needed action and supplies.First 24 Hour Coping Detail Provide a brief description of Procedures

/ Guidelines:

Confirm that procedure/guidance exists or will be developed to support implementation.

The operation of the HCVS is governed the same for SA conditions as for BDBEE conditions.

Existing guidance in the SAMGs directs the plant staff to consider changing radiological conditions in a severe accident.Identify modifications:

List modi(fications and describe how they support the HCVS Actions.The same as for BDBEE Venting Part 2, except:* A modification may be required to ensure accessibility and habitability of the ROS during SA conditions.

A modification will be required to ensure the flammability limits of gases passing through the system are not reached. This modification will install a check valve on the last segment (from the refueling floor to the exhaust) of the new HC VS line.Key Venting Parameters:

List instrumentation credited for the HCVS Actions. Clearly indicate which of those already exist in the plant and what others will he newly installed (to comply with the vent order).The same as for BDBEE Venting Part 2.Notes: None.CNS OIP CNS alp ~~Page 38 of 83 Rvso Revision 2 Cooprt N:Bucleary SttonHadetined Containent Ventin Sysemt Part 2: Boundary Conditions for Wet Well Vent Part 2 Boundary Conditions for WW Vent: HCVS Support Equipment Functions Determine venting capability support functions needed.Ref: EA-13-109 Section 1.2.8, 1.2.9 / NET 13-02 Section 2.5, 4.2.4, 6.1.2 BDBEE Venting Provide a general description of the BDBEE Venting actions support functions.

Identif methods and strategy ies)utilized to achieve venting results.Ref: EA-13-109 Section 1.2.9 / NEL 13-02 Section 2.5, 4.2.2, 4.2.4, 6.1.2 First 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months Pneumatic Power Sunnlv: Existing and newly installed accumulator tanks with back-up portable N 2 bottles will provide sufficient motive force for all HCVS valve operation and will provide for multiple operations of the PC-AOV-A032 vent valve.The existing installed pneumatic supplies (accumulators) for PC-AOV-237AV are currently sized to support venting for 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months in a BDBEE with or without core damage. The accumulator to be installed for PC-AOV-A032 will be sized to support venting for 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months in a BDBEE with or without core damage.First 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months Electric Power Sunnlv: Containment integrity is initially maintained by permanently installed equipment.

All containment venting fuinctions will be performed from the MCR or ROS, except for transferring MOV-233MV power from Division I AC to the PC233MV UPS located in the Reactor Building elevation 958'-3", at or near the MCC-RA. Venting will require support from the HCVS installed UPS batteries, UPS battery charger, and pneumatic supply. This installed equipment will provide a minimum of 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months operation.

Connection points will be provided.All DC and AC power to support HCVS venting will be provided by two dedicated UIPS systems (i.e., the HCVS UPS and PC233MV UPS) with dedicated UPS batteries to support 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months of operation.

Existing safety-related station batteries will provide sufficient electrical power for RCIC operation.

Before station batteries are depleted, portable FLEX diesel generators, as detailed in the response to Order EA-12-049, will be credited to charge the station batteries and maintain DC bus voltage.The UPS to be installed will provide at least 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months of power supplies and support venting for 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months in a BDBEE with or without core damage. The proposed location for the UPS is the far end of the Control Building corridor at the 903'-6" level. This location is proposed based on the seismic class of the Control Building and being above the design basis flood level. The relative absence of other safety-related equipment in that area is also a positive feature. Additionally, this location is in relatively close proximity to both the Control Room and anticipated connection points for FLEX power sources. During the final design evaluation for NFPA 805 Fire PRA compatibility of this new design must be evaluated as well as the effects of an additional combustible and heat source to the area. Floor loading requires an engineered foundation to support the weight of the new equipment.

As described in the section, "Power and Pneumatic Supply Sources," the NCVS UPS will consist of a bank of battery cells providing 120 VDC powering an inverter, which supplies alternate NC VS 12OVAC power, and a 120 VAC Distribution Panel. The battery of choice is a sealed cell (or voltage regulated lead acid -VRLA)due to its minimal hydrogen generation.

The HCVS has no tie to the station batteries 125 DCA, 125 DCB, 250 VDCA or 250VDCB.CNS OIP CNS OIP ~~Page 39 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overali Integrated Pian (EA-1 3-109)Part 2: Boundary Conditions for Wet Well Vent Part 2 Boundary Conditions for WW Vent: HCVS Support Equipment Functions Note that PC-MOV-23 3MV will be powered by a separate alternate power supply. This alternate supply will consist of a UiPS (charger, battery, and inverter) and transfer switch at or near MCC-RA. The transfer switch will provide proper separation of the safety-related control and power circuits for PC-MOV-233MV.

The UPS will provide 480 VAC three phase power for PC-MOV-233MV, and will be sized to provide three operating cycles of the valve during the 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months period before FLEX power or offsite power is restored.See Sketch I of Attachment 3 for a 1-line sketch of the UPS system and PC-MO V-233MV alternate power system.Post-2 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months Pneumatic Power Supply: After 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , pneumatic supply would be provided by portable nitrogen bottles. Pre-staged and pre-connected nitrogen bottles will be available for use in the Mechanical ROS.Post-24 hours Electric Power Supply: If station power is not restored after 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , power to the HCVS Distribution Panel will be provided directly by a FLEX DO (bypassing the UPS battery charger) or by recharging the UPS batteries with a FLEX DG. The transfer switch will be aligned to supply normal AC power to the battery charger during normal operation.

During the Beyond Design Basis event, cables will be connected to the receptacles installed on the transfer switch enclosure and connected to the cables from a FLEX DO.New shuttle valves associated with AOVs: In order to have pneumatic supply of nitrogen after 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , and also to prevent failure of the HCVS due to failure of the solenoid valves to actuate PC-AOV-237AV and PC-AOV-A032, shuttle valves will be newly installed for these AOVs. Failure of the solenoid valves means that alternate AC power and/or alternate pneumatic motive force has been lost. The shuttle valves allow these AOVs to be shifted by pneumatic motive force with the nitrogen from the Mechanical ROS, without power to the solenoid operator.

The newly installed shuttle valves will be located in the totvs area of the associated AOVs, and the piping for the nitrogen supply will go from the shuttle valves to the Mechanical ROS.Severe Accident Venting Provide a general description of the Severe Accident Venting actions support functions.

Identify methods and strategy(ies) utilized to achieve venting results.Ref:" EA-13-109 Section 1.2.8, 1.2.9 / NEL 13-02 Section 2.5, 4.2.2, 4.2.4, 6.1.2 The same support functions that are used in the BDBEE scenario would be used for severe accident venting.Similar to the BDBEE scenario, the UPS will provide power for the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . After 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months however, the power to the UPS battery chargers will either be switched to the FLEX generators evaluated for SA capability or a dedicated FLEX DO.Refer to "Part 2 -Hydrogen" to find a description of the approaches used to prevent the accumulation of flammable gases to support venting operations.

CNS OIP CNS alp ~~Page 40 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent Part 2 Boundary Conditions for WW Vent: HCVS Support Equipment Functions Details Provide a brief description of Procedures

/ Guidelines:

Confirm that procedure/guidance exists or will be developed to support implementation.

Most of the equipment used in the HCVS is permanently installed.

The key portable items are the FLEX D~s, and the nitrogen bottles needed to supplement the air supply to the AOVs after 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . The nitrogen bottles will be permanently staged in the plant for use post-event.

The D~s once deployed post-event will remain in position for the duration of the event. The staging and deployment of this equipment will be incorporated into new or existing procedures as part of the BDBEE/severe accident response.Identify modifications:

List modif/ications and describe how they support the HCVS Actions.FLEX modifications applicable to HCVS operation:

installation of an emergency connection point for a FLEX DO to repower the battery charger of the UPS.HCVS modification:-Add piping from the AOVs to the Mechanical ROS and connection points in the Mechanical ROS to connect portable N 2 bottles for motive force to 1{CVS components after 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . The piping will supply nitrogen from the Mechanical ROS to the new shuttle valves associated with AOVs PC-AOV-237AV and PC-AOV-A032.-Install the two UPS systems to deliver power to the IICVS equipment and I&C: the I-CVS UPS system will consist of battery cells, an inverter, and a l2OVAC distribution panel; the PC233MV UPS will consist of a charger, battery and inverter delivering 4SOVAC three phase power. Install cables from the UPS to the equipment and I&C it powers.HCVS connections required for portable equipment will be protected from all applicable screened-in hazards and located such that operator exposure to radiation and occupational hazards will be minimized.

Structures to provide protection of the HCVS connections will be constructed to meet the requirements identified in NE-I-12-06 Section 11 for screened-in hazards.Key Support Equipment Parameters:

List instrumentation credited for the support equipment utilized in the venting operation.

Clearly indicate which of those already exist in the plant and what others will be newly installed (to comply with the vent order).New equipment:-Pressure gauge on supplemental nitrogen bottles.-Pressure transmitters on the accumulators of air-operated valves.-Indication of UPS electrical power supply availability.

Notes: None.CNS OIP CNS alp ~Page 41. of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Part 2: Boundary Conditions for Wet Well Vent Part 2 Boundary Conditions for WW Vent: HCVS Venting Portable Equipment Deployment Provide a general description of the venting actions using portable equipment including modifications that are proposed to maintain and/or support safety functions.

lef: EA-13-109 Section 3.1 / NET 13-02 Section 6.1.2, D.1.3.1 Deployment pathways for compliance with Order EA- 12-049 are acceptable without further evaluation needed except in areas around the Reactor Building or in the vicinity of the HCVS piping. Deployment in the areas around the Reactor Building or in the vicinity of the HCVS piping will allow access, operation and replenishment of consumables with the consideration that there is potential Reactor core damage and HCVS operation.

Venting actions using portable equipment include the following:-Replenishment of pneumatic supplies:

After the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , the current strategy consists in using portable nitrogen bottles, pre-connected at the Mechanical ROS, in order to provide pneumatic motive force to PC-AOV-237AV and PC-AOV-A032.

Additional portable nitrogen bottles could be brought to the ROB as needed. The on-site location of these nitrogen bottles is an Open Item (Open Item 4).Off-site supplies would relieve the on-site supplies after about 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months in the event. The effect of the vent operation on deployment operations is an Open Item (Open Items 2 and 11).-Repowering the UPS system: After the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , the IICVS Distribution Panel will be provided directly by a FLEX DO (bypassing the UPS battery charger) or by recharging the UPS batteries with a FLEX DO. The transfer switch will be aligned to supply normal AC power to the battery charger during normal operation.

During the Beyond Design Basis event, cables will be connected to the receptacles installed on the transfer switch enclosure and connected to the cables from a FLEX DO. The connection would occur inside the Control Building far from the HCVS piping (on the opposite side of the plant site).Therefore, the connections of power sources should not be affected by the operation of the HCVS. The deployment of these power sources should take into account the operation of the NC VS and should preclude operators from coming in the vicinity of the Reactor Building or the HCVS piping.Details Provide a brief description of Procedures

/ Guidelines:

Confirm that procedure/guidance exists or will be developed to support implementation.

Operation of the portable equipment is the same as for compliance with Order EA-12-049, thus they are acceptable without further evaluation.

The HCVS effluent will exit from the roof of the Reactor Building.

The HCVS UPS and equipment connections will be in and around the Control Building north of the Reactor Building.

The Mechanical ROS is on the south side of the Reactor Building at ground level. Therefore, the procedures/guidelines for HCVS actions are the same as for the support equipment section.[cf. OPEN ITEM I11: Evaluate the impact of SA environmental conditions for post-24 hour actions supporting the implementation of power and pneumatic supplies.]

Implementation procedures are being developed to address all H-CVS operating strategies, including deployment of portable equipment.

Direction to enter the procedure for HCVS operation will be given in the EOPs, the ELAP procedure, and the SAM~s (refer to Part 4 for general information on procedures).

CNS OIP Page 42 of 83 Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Pian (EA-1 3-1 09)Part 2: Boundary Conditions for Wet Well Vent IIICVS Actions Modifications Protection of connections Identif Actions including Identify modijfications.

Identify how the connection is protected.

how the equipment will be deployed to the point of use.Per compliance with Order N/A Per compliance with Order EA-12-049 EA-12-049 (FLEX) (FLEX)Notes: Additional nitrogen bottles can be brought in after 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months for the valve motive force.CNS OIP CNS OIP ~~Page 43 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Pian (EA-1 3-109)Part 3: Boundary Conditions for EA-1 3-1 09. Option B.2 General Licensees that use Option B. 1 ofEA-13-109 (SA Capable DW Vent without SA WA) must develop their own QIP.This template does not provide guidance for that option.Licensees using Option B.2 of EA-13-109 (SAWA and SAWMor S4S°F SADW Vent (SADV) with SAWA) may use this template for their OIP submittal.

Both SA WM and SAD V require the use of SA WA and may not be done independently.

The HCVS actions under Part 2 apply to all of the following:

This Part is divided into the following sections: 3.1: Severe Accident Water Addition (SA WA)3.1I.A: Severe Accident Water Management (SA WM)3.1.B: Severe Accident DW Vent (S4S deg F)Provide a sequence of events and identify any time constraint required for success including the basis for the time constraint SAWA and SA WM or SADV Actions supporting SA conditions that have a time constraint to be successful should be identified with a technical basis and a justijfication provided that the time can reasonably be met (for example, a walkthrough of deployment).

Actions already identified under the HC VS part of this template need not be repeated here.The time to establish the water addition capability into the RPV or DW should be less than 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months from the onset of the loss of all injection sources.*Electrical generators satisfying the requirements ofrEA-12-049 may be credited for powering components and instrumentation needed to establish a flow path.* Time Sensitive Actions (TSAs) for the purpose of SA WA are those actions needed to transport, connect and start portable equipment needed to provide SA WA flow or provide power to SA WA components in the flow path between the connection point and the RP V or drywell. Actions needed to establish power to SA WA instrumentation should also be included as TSAs.Ref: NET 13-02 Section 6.1.1.7.4.1, 1.1.4, L.1.5 The operation of the H{CVS using SAWA and SAWMISADV will be designed to minimize the reliance on operator actions in response to hazards listed in Part 1. Initial operator actions will be completed by plant personnel and will include the capability for remote-manual initiation from the HCVS control station in the MCR.A list of the remote manual actions performed by plant personnel to open the HCVS vent path can be found in Table 2-I. In addition, HGVS operation may occur at the ROS.Timelines (see Attachments 2.1 .A for SAWA/ SAWM) were developed to identify required operator response times and actions. The timelines are an expansion of Attachment 2A and begin either as core damage occurs (SAWA) or after initial SAWA injection is established and as flowrate is adjusted for option E.2 (SAWM). The timelines do not assume the core is ex-vessel and the actions taken are appropriate for both in-vessel and ex-vessel core damage conditions.

CNS OIP CNS OIP ~~Page 44 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall integrated Plan (EA-1 3-109)Part 3.1 : Boundary Conditions for SAWA Table 3.1 -SAWA Manual Actions Primary Action Primary Location / Notes Component 1. Establish HCVS capability in MCR Vertical Board H. Applicable to SAWA/SAWM accordance with Part 2 of this strategy.guidance.

_________________

2. Connect SAWA pump (FLEX Southeast of the Turbine The SAWA pump (FLEX Pump Pump (Godwin))

to water Building adjacent to the "A" (Godwin))

to be located either source. CST. South or North of the Turbine Building.or Northeast of the Turbine Building adjacent to the Missouri River.3. Route 5-inch flexible hose(s) 882'-6" Elevation of the The Emergency Core Flooding (up to three (3)) from the Control Building.

Crosstie which provides water valved connections on the injection into the RPV via the "A" 882'-6" Elevation of the LPCI injection line which inns Control Building to the from the outlet side of the "A" RHRISW FLEX connections.

RHR Heat Exchanger to the recirculation system piping and then into the reactor vessel.4. Route 5-inch flexible hose(s) From SAWA pump (FLEX (up to three (3)) from the Pump (Godwin))

located SAWA pump (FLEX Pump Southeast of the Turbine (Godwin))

to the connections Building adjacent to the "A" in the Control Building CST to the connections Elevation 903' corridor, within the Control Building Elevation 903' corridor.5. Prior to battery expenditure, RHR valves may be operated open 24" RHR-MO-25A from from the MCR. The flexible the MCR and/or connect the hose connection point manual portable FLEX diesel valves will be operated at the generators to the load side of 882'-6" Elevation of the the 'C' Battery Charger Control Building.manual transfer switches EE-SW-LXTX(250) and EE-SW-LXTX(125).

6. Inject to RPV using the diesel N/A Initial SAWA injection rate is driven SAWA pump (FLEX greater than 400 gpm. 400 gpm is Pump (Godwin)).

the equivalent to the RCIC pump flow and greater than 400 gpm can be provided by the SAWA pump (FLEX Pump (Godwin)).

CNS OIP Page 45 of 83 Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109), Part 3.1 : Boundary Conditions for SAWA 7. Monitor SAWA indications.

N/A Injection flow indication from the FLEX Pump (Godwin) will be obtained with a flow meter package supplied from the pump manufacturer (Godwin).24" RLHR-MO-25A valve position will be verified from the MCR.8. Use SAWM to maintain 'FLEX Pump (Godwin) pump Monitor DW Pressure and availability of the WW vent 'performance and flow rate Suppression Pool Level in MCR.(Part 3.1.A). local to the pump.Control SAWA at pump skid.Discussion of timneline SAWA identified items HCVS operations arfe discussed under Phase 1 of EA-13-109 (Part 2 of this OlP).Less than S Hours -Establish electrical power to the load side of the 'C' Battery Charger manual transfer switches EE-SW-LXTX (250) and EE-SW-LXTX (125) or to Critical Switchgear iF & 1G located in the 932' Reactor Building needed to support the strategies for EA-13-109, Phase 1 and Phase 2. Action being taken within the Reactor Building after RPV level lowers to 213 core height must be evaluated for radiological conditions assuming permanent containment shielding remains intact. (HCVS-FAQ-1 2)All other actions required are assumed to be in-line with the FLEX timeline submitted in accordance with the EA-l12-049 requirements.

The connections necessary to support the SAWA/SAWM are located within the Control Building.Less than 8 Hours -Initiate SAWA flow to the RPV. Having the HCVS in service will assist in minimizing the peak DW pressure during the initial cooling conditions provided by SAWA.Severe Accident Operation Determine operating requirements for SA WA, such as may be used in an ELAP scenario to mitigate core damage.Ret: EA-13-109 Attachment 2, Section B.2.2, 11.2.3 / NEI 13-02 Section 1.1.6, L1.4.4 It is anticipated that SAWA will be used in Severe Accident Events based on presumed failure of injection systems or presumed failure to implement an injection system in a timely manner leading to core damage. This does not preclude the use of the SAWA system to supplement or replace the EA-12-049 injection systems if desired. SAWA will consist of both portable and installed equipment.

The motive force equipment needed to support the SAWA strategy shall be available prior to T=8 hours from the loss of injection (assumed at T=0).The SAWA flow path includes methods to minimize exposure of personnel to radioactive liquids / gases and potentially flammable conditions by inclusion of backflow prevention.

Check valve 24" RHR-26CV is included in the Low Pressure Coolant Injection flowpath to prevent backflow from the RPV to the connection point at the 882' -6" Elevation of the Control Building.CNS OIP Page 46 of 83 Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 3.1 : Boundary Conditions for SAWA Description of SAWA actions for first 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months s: T<C 1 in:* No evaluation required for actions inside the Reactor Building for SAWA.T = 1 -7hin:* Evaluation of core gap and early in vessel release impact to Reactor Buildin2 access for SAWA actions is required.

It is assumed that Reactor Building access is limited due to the source term at this time unless otherwise noted. (Refer to HCVS-FAQ-12 for actions in T=l-7 hr). Expected actions are: o No actions are required in the Reactor Building.*Establish backup electrical power for SAWA systems and indications using EA-12-049, or other systems.o Prior to battery expenditure, open 24" RHR-MO-25A from the MCR and/or connect the portable FLEX diesel generators to the load side of the 'C' Battery Charger manual transfer switches EE-SW-LXTX(250) and EE-SW-LXTX(125).

Establish flow to RPV using SAWA systems. Begin injection at a maximum rate, greater than 400 win.o Connect SAWA pump (FLEX Pump (Godwin))

to water source.o Route 5-inch flexible hose(s) (up to three (3)) from the valved connections on the 882'-6" of the Control Building to the RLHRISW FLEX connections.

o Route 5-inch flexible hose(s) (up to three (3)) from the SAWA pump (FLEX Pump (Godwin))to the connections in the Control Building Elevation 903' corridor.o Connect flow meter(s) on the discharges of the SAWA pump (FLEX Pump (Godwin)).

o Inject to RPV using the diesel driven SAWA pump (FLEX Pump (Godwin)).

T_<8-l2hr:

° Continue injection for 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months after SAWA injection begins at initial SAWA rate.T <l2 hrs:* Proceed to SAWM actions (Part 3.l.A)o Reduce the SAWA injection flow rate from greater than 400 gpm to approximately SO gpm.o Monitor Suppression Pool level (Chi 2 PC-LRPR-1B

-Level Recorder Pressure Recorder 1lB)Torus Level (input: PC-DPT-3B2).

o Monitor Suppression Pool pressure (Ch 5 PC-LRPR-IB

-Level Recorder Pressure Recorder iB) Torus Pressure (input: PC-PT-30B).

o Monitor SAWA pump (FLEX Pump (Godwin))

operation and flow rate locally at the pump instrumentation.

o Based on the information obtained above, adjust the output of the FLEX Pump (Godwin) such that the Suppression Pool level remains constant or slowly raises.o Continue to monitor the above parameters and adjust the discharge flow rate of thle FLEX Pump (Godwin) to maintain Suppression Pool level throughout the remainder of the event or until a means of reliable Alternate Decay Heat Removal and pressure control is established.

CNS 0IP Pane 47 of 83 Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 3.1 : Boundary Conditions for SAWA Greater Than 24 Hour Coping Detail Provide a general description of the SAWA actions for greater than 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months using portable and installed equipment including station modijfications that are proposed.Ref: EA-13-109 Attachment 2, Section B.2.2, B.2.3/ NEI 13-02 Section 4.2.2.4.1.3.1, 1.1.4, SAWA Operation is the same for the full period of sustained operation.

If SAWM is employed flow rates will be directed to preserve the availability of the HCVS wetwell vent (see Part 3.1.A).Details Details of Design Characteristics/Performance Specifications SAWA shall be capable of providing a RPV injection rate of greater than 400 gpm within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months of a loss of all RPV injection following an EMAP/Severe Accident.

LAWA shall meet the design characteristics of the HCVS with the exception of the dedicated 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months power source. Hydrogen mitigation is provided by backflow prevention for SA WA.Ref: EA-13-109 Attachment 2, Section B.2.1, R.2.2, B3.2.3/ NET 13-02 Section 1.1.4 Equipment Locations/Controls/Instrumentation:

The locations of the SAWA equipment and controls, as well as ingress and egress paths have been evaluated for the expected severe accident conditions (temperature, humidity, radiation) for the Sustained Operating period.Equipment has been evaluated to remain operational throughout the Sustained Operating period. Personnel exposure and temperature

/ humidity conditions for operation of SAWA equipment will not exceed the limits for ERO dose and plant safety guidelines for temperature and humidity.The flow path will be from the FLEX pump suction at the drain connection of the "A" CST through the FLEX pump with multiple outlets with individual flow indicators.

To provide the required flow control with the selected pump (Godwin), a recirculation path will be provided to ensure the pump flow is within the normal operating range of the pump. As required, flow indicator(s) will be dedicated to the unit in a Severe Accident, and the flow that is provided to the RLHR service water FLEX header will be monitored.

The monitored water flow rate will pass through the RHRSW piping to the RIIR System Enjection Flow Path Crosstie (Upstream of SW-V-120) inside the Control Building where it will connect with the RHR system in the Reactor Building by manually opening SW-V-120 and the 10" butterfly valve that interconnect the systems. The flow will then be directed into the RLPV via the LPCI injection valve (24" RI-R-MO-25A) from the MCR. DW pressure and Suppression Pool level will be monitored and flow rate will be manually adjusted by use of the FLEX pump control valve local to the pump.Communication will be established between the MCR and the FLEX pump location.RHR-MOV-MO25A is the only MOV that has to be opened to support SAWA. This is a DC powered MOV and is already supplied power via the station batteries.

The FLEX DG is located near the Control Building which is significant distance from the discharge of the HCVS at the top of the Reactor Building.

Refueling of the FLEX DG will be accomplished from the various diesel fueled items or from the DO fuel oil tanks as described in the EA-12-049 compliance documents.

The "A" CST or the Missouri River are both a significant distance from the discharge of the IICVS at the top of the Reactor Building.Evaluations for projected SA conditions (radiation

/ temperature) indicate that personnel can complete the initial and support activities without exceeding the ERO-allowable dose for equipment operation or site safety standards.(Reference 24, HCVS-WP-02)

CNS OIP Page 48 of 83 Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overali Integrated Plan (EA-l13-l09)

Part 3.1 : Boundary Conditions for SAWA Electrical equipment and instrumentation will be powered from the existing station batteries.

The battery chargers are also powered from the EA-12-049 generator to maintain the battery capacities during the Sustained Operating period. The indications include (* are minimum): Parameter Instrument Location Power Source / Notes*DW Pressure PC-PT-4B2 and PC-PT- MCR Station batteries via 5B2 (PC-LRPR-1A Ch 3 EA-12-049 generator and PC-LRPR-1A Ch 4)*Suppression PC-DPT-3B2 (PC- MCR Station batteries via Pool Level LRPR-l1A Ch 2) EA-1 12-049 generator*SAWA Flow FLEX Pump Flow FLEX Pump FLEX pump (skid indicator Skid powered device)SAWA pump On-Board Generator FLEX Pump EA-12-049 generator instrumentation Skid Valve controls MCR Panels MCR and Station batteries via and indicationl Control EA- 12-049 generator____ ____ ___ ____ __ ____ ____ ___ ____ ___ Building _ _ _ _ _ _ _ _ _ _ _The instrumentation and equipment being used for SAWA and supporting equipment has been evaluated to perform for the Sustained Operating period under the expected radiological and temperature conditions.

Equipment Protection:

Any SAWA component and connections external to protected buildings have been protected against the screened-in hazards of EA-12-049 for the station.There are no external SAWA connections or components.

Portable equipment used for SAWA implementation will meet the protection requirements for storage in accordance with the criteria in NEI 12-06 Revision 0.Ref: EA-13-109 Attachment 2, Section B.2.2, B.2.3 / NET 13-02 Section 5.1.1, 5.4.6, 1.1.6 Provide a brief description of Procedures

/ Guidelines:

Confirm that procedutre/guidance exists or will be developed to support implementation.

Ref: EA-13-109 Attachment 2, Section A.3.1, B3.2.3 / NET 13-02 Section 1.3, 6.1.2* Hook up FLEX pump to water source at either the "A" CST drain connection or to the Missouri River and to the connections in the Control Building corridor at Elevation 903' per FLEX Support Guidelines.

Connect the valved outlets in the 882'-6" Elevation of the Control Building to the RUR System Injection Flow Path Crosstie (Upstream of SW-V-120).

Hook-up and start FLEX DG to repower 125 VDC "IC" Battery Charger and 250VDC "IC" Battery Charger.* Manually open SW-V-120 and the 10" interconnect butterfly valve to cross tie RHR with RHzRSW.CNS OIP Page 49 of 83 Revision Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Part 3.1: Boundary Conditions for SAWA* Open 24" R.HR-MO-25A using MCR Switches for RHR LPCI injection pathway.* Start FLEX pump.* Adjust flow rate using local flow indicator and manual control valve.Identify modifications:

List modifications and describe how they support the SA WA Actions.Ref: EA-13-109 Attachment 2, Section B.2.2, / NEI 13-02 Section 4.2.4.4, 7.2.1.8, Appendix I None.Component Qualifications:

State the qualification used for equipment supporting SA WA.Ref: EA-13-109 Attachment 2, Section B.2.2, B.2.3 / NEI 13-02 Section 1.1.6 Permanently installed plant equipment shall meet the same qualifications as described in Part 2 of this OWP.Temporary/portable equipment shall be qualified and stored to the same requirements as FLEX equipment as specified in NEI 12-06 Rev 0. SAWA components are not required to meet NEI 13-02, Table 2-1 design conditions.

Notes: None.CNS OIP CNS OIP ~~Page 50 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Jntegrated Plan (EA-1 3-109)Part 3.1 .A: Boundary Conditions for SAWA/SAWM~

Time periods for the maintaining SAWM actions such that the WW vent remains available SA WM Actions supporting SA conditions that have a time constraint to be successful should be identified with a technical basis and a justifcation provided that the time can reasonably be met (for example, a walkthrough of deployment).

Actions already identified under the HG VS part of this template need not be repeated here.There are three time periods for the maintaining SA WM actions such that the WW vent remains available to remove decay heat from the containment:

SA WM can be maintained for > 7 days without the need for a drywell vent to maintain pressure below PCPL or containment design pressure, whichever is lower.o Under this approach, no detail concerning plant modifications or procedures is necessary with respect to how alternate containment heat removal will be provided.°SAWMcan be maintained for at least 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , but less than 7days before DWpressure reaches PGPL or design pressure, whichever is lower.o Under this approach, a functional description is required of how alternate containment heat removal might be established before DW pressure reaches P'CPL or design pressure whichever is lower. Under this approach, physical plant modijfications and detailed procedures are not necessary, but written descriptions of possible approaches f or achieving alternate containment heat removal and pressure control will be provided.* SA WM can be maintained for < 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months SAWM strategy can be implemented but for less than 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months before DW pressure reaches PCPL or design pressure whichever is lower.o Unlder this approach, a functional description is required of how alternate containment heat removal might be established before DW pressure reaches PCPL or design pressure whichever is lowver. Under this approach, physical plant modifications and detailed procedures are required to be implemented to insure achieving alternate containment heat removal and pressure con trol will be provided for the sustained operating period.Ref: NEI 13-02 Appendix C.7 SAWM can be maintained for >7 days without the need for a drywell vent to maintain pressure below PCPL.Basis for SAWM time frame Option 1 -SAWM can be maintained greater than or equal to 7 days: CNS is bounded by the evaluations performed in BWROG TP-201 5-008 and representative of the reference plant rn NEI 13-02 figures C-2 through C-6. GNS has a Rated Thermal Power of 2419 MWt. The Reference Plant (Peach Bottom) had a Rated Thermal Power of 3514 MWt at the time of the evaluations.

Therefore, the ratio of plant powers is 1.45 (3514/2419).

The ratio of the core power to the containment free volume is a standard indication of the capacity of the plant to cope with an accident involving loss of containment heat removal. Peach Bottom has a ratio of approximately 12.5 (3514 MWt/28 1,500 ft 3), while the ratio for CNS is approximately 10 (2419 MWt/239, 100 ft 3). Both Peach Bottom and CNS have approximately the same pressure suppression chamber free volume at 112,000 ft 3.Based on these ratios and parameters, the heat capacity at GNS is bounded by that at the Reference Plant (Peach Bottom).Instrumentation relied upon for SAWM operations is DW pressure, Suppression Pool level and SAWA flow.DW pressure, Suppression Pool level are initially powered by the HCVS TIPS (first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months ) and then by the FLEX (EA-1 2-049) generator.

SAWA flow indication is powered by the integral generator supplied with the FLEX Pump (Godwin).

The DO will provide power throughout the Sustained Operation period (7 days).CNS OIP Page 51 of 83 Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-13-l09)

Part 3.1 .A: Boundary Conditions for SAWA/SAWM DW Temperature monitoring is not a requirement for compliance with Phase 2 of the Order, but some knowledge of temperature characteristics provides information for the operation staff to evaluate plant conditions under a severe accident and provide confirmation to adjust SAWA flow rates. (C.7.1.4.2, C.8.3.1)Suppression Pool level indication is maintained throughout the Sustained Operation period, so the HCVS remains in-service.

The time to reach the level at which the WW vent must be secured is >7days using SAWM flowrates (C.6.3, C.7. 1.4.3)Procedures will be developed that control the Suppression Pool level, while ensuring the DW pressure indicates the core is being cooled, whether in-vessel or ex-vessel.

Procedures will dictate conditions during which SAWM flowrate should be adjosted (up or down) using suppression pool level and DW pressure as controlling parameters to remove the decay heat from the containment. (This is similar to the guidance currently provided in the BWROG SAM~s) (C.7.1.4.3)

Attachment 2.1.A shows the timeline of events for SAWA / SAWM. (C.7.1.4.4)

Table 3.1.B -SAWM Manual Actions Primary Action Primary Location / Component Notes 1. Lower SAWA Southeast of the Turbine Building Control to maintain containment injection rate to control adjacent to the "A" CST. and vWW parameters to ensure Suppression Pool level WW vent remains functional.

and decay heat or removal. 80.4 gpm minimum capability is Northeast of the Turbine Building maintained for greater than 7___________________adjacent to the Missouri River. days.2. Control to SAWM Southeast of the Turbine Building SAWM flow rates will be flowrate for adjacent to the "A" CST and monitored using the following containment control / MCR. instrumentation:

decay heat removal. o FLEX pump flow or a Suppression Pool level a DW pressure Northeast of the Turbine Building adjacent to the Missouri River and SAWM flow rates will be MCR. controlled using the manual flow______________________control valve at the FLEX pump.3. Establish alternate Yard >7 days source of decay heat removal.4. Secure SAWA /SAWM.Southeast of the Turbine Building adjacent to the "A" CST.When reliable alternate containment decay heat removal is established.

or Northeast of the Turbine Building adjacent to the Missouri River.CNS OIP CNS GIP ~~Page 52 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Part 3.1 .A: Boundary Conditions for SAWAISAWM SAWM Time Sensitive Actions Time Sensitive SAWM Actions: 12 Hours -Initiate actions to maintain the WW vent capability by lowering injection rate, while maintaining the cooling of the core debris (SAWM). Monitor SAWM[ critical parameters while ensuring the WW vent remains available.

SAWM Severe Accident Operation Determine operating requirements for SA WM, such as may be used in an ELAP scenario to mitigate core damage.Ret: EA-13-109 Attachment 2, Section R.2.2, B3.2.3 I NET 13-02 Appeadix C It is anticipated that SAWM will only be used in Severe Accident Events based on presumed failure of plant injection systems per direction by the plant SAMGs. Refer to Attachment 2.1I .D for SAWM SAMG language additions.

First 24 Hour Coping Detail Provide a general description of the SA WM actions forfirst 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months using installed equipment including station inmdifications that are proposed.Given the initial conditions for EA-13-J109:

BDBEE occurs with ELAP* Failure of all injection systems, including steam-powered injection systems Ret: EA-13-109 Section 1.2.6, Attachment 2, Section B3.2.2, B.2.3 l NET 13-02 2.5, 4.2.2, Appendix C, Section C.7 SAWA will be established as described above. SAWM will use the installed instrumentation to monitor and adjust the flow from SAWA to control the pump discharge to deliver flowrates applicable to the SAWM strategy.Once the SAWA initial low rate has been established for 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months , the flow will be reduced while monitoring DW pressure and Suppression Pool level. SAWM flowrate can be lowered to maintain containment parameters and preserve the WW vent path. SAWM will be capable of injection for the period of Sustained Operation.

Greater Than 24 Hour Coping Detail IProvide a general description of the SA WMactions for greater than 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months using portable and installed equipment including station modifications that are proposed.Ref: EA-13-109 Section 1.2.4, 1.2.8, Attachment 2, Section B3.2.2, B3.2.3 / NET 13-02 Section 4.2.2, Appendix C, Section C.7 SAWM can be maintained

>7 days: The SAWM flow strategy will be the same as the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months until 'altemate reliable containment heat removal and pressure control' is reestablished.

SAWM flow strategy uses the SAWA flow path. No additional modifications are Ibeing made for SAWM.CN50IP CNS OiP ~~Page 53 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overali Integrated Plan (EA-1 3-109)Part 3.1 .A: Boundary Conditions for SAWAISAWM Details Details of Design Characteristics/Performance Specifications Ref: EA-13-109 Attachment 2, Section B1.2.2, B.2.3 / NET 13-02 Section Appendix C SAWM shall be capable of monitoring the containment parameters (DW pressure and Suppression Pool level) to provide guidance on when injection rates shall be reduced, until alternate containment decay heat/pressure control is established.

SAWA will be capable of injection for the period of Sustained Operation.

Equipment Locations/Controls/Instrumentation Describe location for SA WMrnonitoring and control.Ref: EA-13-109 Attachment 2, Section B1.2.2, 11.2.3 / NET 13-02 Appendix C, Section C.8, Appendix I The SAWM control location is the same as the SAWA control location.

Local indication of SAWM flow rate is provided at the pump skid by pump vendor provided flow instrument qualified to operate under the expected environmental conditions.

The SAWA flow instrument is powered by the SAWA pump skid diesel engine alternator.

Communications will be established between the SAWM control location and the MCR.Injection flowrate will be controlled by a FLEX manual valve located on the FLEX pump.Suppression Pool level and DW pressure are read in the control room using indicators powered by the FLEX DO installed under EA-12-049.

These indications are used to control SAWM flowrate to the RPV.Key Parameters:

List instrumentation credited for the SA WMActions.

Parameters used for SAWM are:*DW Pressure*Suppression Pool Level* SAWM Flowrate The DW pressure and Suppression Pool level instruments are qualified to RG 1.97 and are the same as listed in Part 2 of this OIP'. The SAWM flow instrumentation will be qualified for the expected environmental conditions expected when needed.Notes: None.CNS OIP CNS OIP ~~Page 54 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Pian (EA-1 3-1 09)Part 3.1 .B: Boundary Conditions for SAWA/SADV Applicability of WW Design Considerations CNS will not be using SAWA!SADV.

Table 3.1.C -SADV Manual Actions Timeline for SADV Severe Accident Venting First 24 Hour Coping Detail Greater Than 24 Hour Coping Detail Details: CNS OIP CNS OiP ~~Page 55 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 4: Programmatic Controls.

Training.

Drills and Maintenance Identify how the programmatic controls will be met Provide a description of the programmatic controls equipment protection, storage and deployment and equipment quality addressing the impact of temperature and environment.

Ref': EA-13-109 Section 1.2.10, 3.1, 3.2 / NEI 13-02 Sections 5, 6.1.2, 6.1.3, 6.2 Program Controls: The HCVS venting actions will include:* Site procedures and programs are being developed in accordance with NET 13-02 to address use and storage of portable equipment relative to the Severe Accident defined in NRC Order BA-i13-109 and the hazards applicable to the site per Part i of this OIl'.* Routes for transporting portable equipment from storage location(s) to deployment areas will be developed as the response details are identified and finalized.

The identified paths and deployment areas will be analyzed for radiation and temperature to ensure they are accessible during Severe Accidents.

Procedures:

IProcedures will be established for system operations when normal and backup power is available, and during ELAP conditions.

The HCVS procedures will be developed and implemented following the plants process for initiating or revising procedures and will contain the following details:* appropriate conditions and criteria for use of the HCVS,* when and how to place the HCVS in operation,* the location of system components,* instrumentation available, o normal and backup power supplies,* directions for sustained operation, including the storage location of portable equipment,* training on operating the portable equipment, and* testing of portable equipment The procedures should state that "use of the vent may impact NPSH." CNS will establish provisions for out-of-service requirements of the HCVS and compensatory measures.

The following provisions will be documented in a controlled document: The provisions for out-of-service requirements for HCVS/SAWA flmctionality are applicable in Modes 1, 2 and 3.*If for up to 90 consecutive days, the primary or alternate means of HCVS/SAWA operation are non-functional, no compensatory actions are necessary.

If for up to 30 days, the primary and alternate means of HCVS/SAWA operation are nonfunctional, no compensatory actions are necessary.

CNS OIP Page 56 of 83 Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 4: Programmatic Controls, Trainingh Drills and Maintenance If the out of service times exceed 30 or 90 days as described above, the following actions will be performed through the corrective action program: o The cause(s) of the non-functionality, o The actions to be taken and the schedule for restoring the system to functional status and prevent recurrence, o Initiate action to implement appropriate compensatory actions, and o Restore full HCVS functionality at the earliest opportunity not to exceed one full operating cycle.OPEN ITEM 12: Determine the control document for HCVS out of service time criteria.Describe training plan List training plans for affected organizations or describe the plan for training development.

Ref': EA-13-109 Section 3.2/INET 13-02 Section 6.1.3 Personnel expected to perform direct execution of the HCVS/SAWA/SAWM actions will receive necessary training in the use of plant procedures for system operations when normal and backup power is available and during EIJAP conditions.

The training will be refreshed on a periodic basis and as any changes occur to the HCVS/SAWA/SAWM actions, systems or strategies.

Training content and frequency will be established using the Systematic Approach to Training process.In addition, (per Reference 10 (NET 12-06)) all personnel on-site will be available to supplement trained personnel.

Identify how the drills and exercise parameters will be met Alignment with NEI113-06 and 14-01 as codijfied in NTTF Recommendation 8 and 9 rulemaking.

The Licensee should demonstrate use of the HCVS/SAWA/SA WMsystem in drills, tabletops, or exercises as follows:*Hardened containment vent operation on normal power sources (no ELAP).*During FLEX demonstrations (as required by EA-12-049

Hardened containment vent operation on backup power and from primary or alternate location during conditions of FLAP/loss of /HAS with no core damage.System use is for containment heat removal AND containment pressure control.*HCVS operation on backup power and from primary or alternate location during conditions of ELA P/loss o] /HAS with core damage. System use is for containment heat removal AND containment pressure con trol with potential for combustible gases (Demonstration may be in con]junction with SAG change).*Operation for sustained period with SA WA and SA WM to provide decay heat removal and containment pressure control.Ret': EA-113-109 Section 3.1 / NEL 13-02 Section 6.1.3 The site will utilize the guidance provided in NEI 13-06 and 14-01 for guidance related to drills, tabletops, or exercises for HGVS operation.

In addition, the site will integrate these requirements with compliance to any rulemaking resulting from the NTI7F Recommendations 8 and 9.Describe maintenance plan Describe the elements of the maintenance plan.The maintenance program should ensure that the HC VS/SA WA/SA WM equipment reliability is being achieved in a manner similar to that required for FLEX equipment.

Standard industry templates (e.g., EPRI) and CNS OIP Page 57 of 83 Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 4: Programmatic Controls, Training, Drills and Maintenance associated bases may be developed to define specijfic maintenance and testing.o Periodic testing and frequency should be determined based on equipment type, expected use and manufacturer'"s recommendations (further details are provided in Part 6 of this document).

o Testing should be done to verify design requirements and/or basis. The basis should be documented and deviations from vendor recommendations and applicable standards should be justified o Preventive maintenance should be determined based on equipment type and expected use. The basis should be documented and deviations from vendor recommendations and applicable standards should be justifWed o Existing work control processes may be used to control maintenance and testing.*HCVS/SA WA permanent installed equipment should be maintained in a manner that is consistent with assuring that itperforms its funcetion when required.o HCVS/SA WA permanently installed equipment should be subject to maintenance and testing guidance provided to verify proper fun ction.* HCVS/SA WA non-installed equipment should be stored and maintained in a manner that is consistent with assuring that it does not degrade over long periods of storage and that it is accessible for periodic maintenance and testing.Ref: EA-13-109 Section 1.2.13 / NEI 13-02 Section 5.4, 6.2 The site will utilize the standard EPRI industry PM process (Similar to the Preventive Maintenance Basis Database)for establishing the maintenance and testing actions for IICVS/SAWAISAWM components.

The control program will include maintenance guidance, testing procedures and frequencies established based on type of equipment and considerations made within the EPRI guidelines.

CNS will implement the following operation, testing and inspection requirements for the HCVS and SAWA to ensure reliable operation of the system.Table 4-1: Testing and Inspection Requirements Description Frequency Cycle the HCVS and installed SAWA valves 1 and Once per every/ operating cycle.the interfacing system boundary valves not used to maintain containment integrity during Modes 1, 2 and 3. For HCVS valves, this test may be performed concurrently with the control logic test described below.Cycle the HCVS and installed SAWA check valves Once per every other 4 operating cycle.not used to maintain containment integrity during unit operations.

3 Perform visual inspections and a walk down of Once per every other 4 operating cycle.HCVS and installed SAWA components.

CNS OIP CNS OIP ~~Page 58 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Part 4: Programmatic Controls, Training, Drills and Maintenance Test and calibrate the H-CVS radiation monitors.Oneproraigcl.

Once per operating cycle.Leak test the HCVS. 1. Prior to first declaring the system functional;

2. Once every three operating cycles thereafter; and 3. After restoration of any breach of system boundary within the buildings.

Validate the HCVS operating procedures by Once per every other operating cycle.conducting an open/close test of the HCVS control function from its control location and ensuring that all HCVS vent path and interfacing system boundary valves 5 move to their proper (intended) positions.

SNot required for HCVS and SAWA check valves.2 After two consecutive successful performances, the test frequency may be reduced to a maximum of once per every other operating cycle.3Not required if integrity of check function (open and closed) is demonstrated by other plant testing requirements.

4~ After two consecutive successful performances, the test frequency may be reduced by one operating cycle to a maximum of once per every fourth operating cycle.SInterfacing system boundary valves that are normally closed and fail closed under ELAP conditions (loss of power ,and/or air) do not require control function testing under this part. Performing existing plant design basis function testing or system operation that reposition the valve(s) to the HCVS required position will meet this requirement without the need for additional testing.Notes: None.CNS OIP CNS OIP ~~Page 59 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 5: Milestone Schedule Provide a milestone schedule This schedule should include:* Modifications timeline* Procedure guidance development complete o HCVS Actions o Maintenance

Storage plan (reasonable protection)

Staffing analysis completion

Long term use equipment acquisition timeline* Training completion for the HCVS Actions The dates specifically required by the order are obligated or committed dates. Other dates are planned dates subject to change. Updates will be provided in the periodic (six month) status reports.Ref: EA-13-109 Section D.1, D.3 / NEL 13-02 Section 7.2.1 The following milestone schedules are provided.

The dates are planning dates subject to change as design and implementation details are developed.

Any changes to the following target dates will be reflected in the subsequent 6 month status reports.Phase 1 Milestone Schedule: Phase 1 Milestone Schedule Milestone Target Activity Comments Completion Status (Include date Date changes in this column?Hold preliminary/conceptual design meeting June 2014 Complete Submit Overall Integrated Implementation June 2014 Complete Plan Submit 6 Month Status Report December 2014 Complete Submit 6 Month Status Report June 2015 Complete Design Engineering On-site/Complete September 2015 Complete Submit 6 Month Status Report December 2015 Complete Simultaneous with Phase 2 OIl)Submit 6 Month Status Report June 2016 Not Started Operations Procedure Changes Developed August 2016 Not Started Site Specific Maintenance Procedure August 2016 Not Started Developed Training Complete September 2016 Not Started CNS OIP Page 60 of 83 L Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Part 5: Milestone Schedule Implementation Outage October 2016 Not Started Procedure Changes Active November 2016 Not Started Walk Through Demonstration/Functional November 2016 Not Staffed Test Phase 2 Milestone Schedule: Phase 2 Milestone Schedule Milestone Target Activity Comments Completion Status (Include date Date changes in this column/Hold preliminary/conceptual design meeting Complete]Submit Overall Integrated Implementation December 2015 Complete Plan Submit 6 Month Status Report June 2016 Submit 6 Month Status Report December 2016 Submit 6 Month Status Report June 2017 Design Engineering On-site/Complete October 2017 Started Submit 6 Month Status Report December 2017]Operations Procedure Changes Developed May 2018 ISite Specific Maintenance Procedure May 2018 Developed Training Complete June 2018 Submit 6 Month Status Report June 2018 Submit 6 Month Status Report June 2018 Implementation Outage October 2018 Walk Through Demonstration/Functional October 2018 Test Procedure Changes Active October 2018 ,Submit Completion Report January 2019 (60 days after full compliance)

Notes: None.CNS OIP CNS OIP ~~Page 61 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overail Integrated Plan (EA-1 3-1 09)Attachment 1: HCVSISAWA Portable Equipment BDBEE Severe Performance Maintenance 1 PM List portable equipment Venting Accident Criteria Requirements Venting Nitrogen Cylinders X X X Check periodically for pressure, replace or replenish as needed FLEX DG (and associated equipment)

X X TBD Per Response to EA-12-049 SAWA Pump (and associated X X >4OO gpm for Per Response to EA-1 3-1 09 equipment) first 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months and 80.4 gpm_____________

____________

____________for first_7_days

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _CNS OIP CNS OIP ~~Page 62 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Attachment 2A: Seauence of Events Timeline -HCVS t t~lhr t=0s RCIC ELAP SBO starts Declared i No Injection t, 8 hrs Anti~patowy venting Case 1 FLEX Successful Reft CNS FLEX DIP t1-18 hr'sSAWA Injection Begins ]NO injection lJ Level at , : Case 2_ ,k_ Ret SECY-12-0157 t'23 hrs t,24 hrs 1 34 FII~Contaien exceed+ient Venting tl11hrs+n peetig B at MCR orROS muPCPL) HCVS pneumatic mnd battery status.I No replenshment expected to be 9..* e quiebefore t=24hor t" 12 hr'F-. Transfer to 4-----.Level at TAF t, 24 hrs Replenishment of HCVS powKer nd pneumatic Case 3 RCIC Early Failure Ret: SOARCA w -SAW 1 ' ~~r t 8 hrs tll11hrs tl,1hrs tl,2hrs t"24 hr's Legend ,,,,,-Adequate core cooling maintained

-Injecton Lost-Increased shine and leakage of radionudides primarily from Wetwell HCVS Post Core Damage Dose Evaluation Required HCVS lime evaluation required

References:

Case 1: CNS FLEX Overall integrated Plan Case 2: SECY-12-0157

-ML12344A030 Case 3: SOARCA -ML13150A053 CNS OIP CNSOIP ~~Page 63 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Attachment 2.1 .A: Sequence of Events Timeline -SAWA I SAWM S AWA Injection Flow begins (<500 gpm)Sustained Operation period T=1t[8 hr Control SW flwrate using drywell pressure and suppression pool level indications T=72 hr C'f litiMonitor containment parameters and conditions NEI 13-02 0.7.1 L I WW vent becomes I unavailable Monitor containment parameters F.-.0 *6 .0 *,ui~JimIirng.IpueuI.Ippuipu.n.~j 0 NEI 13-02C.7.3

, va=I I Monitor containment Sparameters 0*rNEI 13-02 C.7.2 1 CNS OIP CNSOIP ~~Page 64 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-13-109)

Attachment 2.1 .B: Sequence of Events Timeline -SADV CNS will not install a Severe Accident Drywell Vent CNS OIP CNS OIP ~~Page 65 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Attachment 2.1 .C: SAWA / SAWM Plant-Specific Datum Drywell floor Wetwell Level Instrument Range (0 to +30 ft H 2 0)Wetwell Level-(Max. LCO 12.92 ft)Freeboard Height (15.6 ft)Rate of change of torus level at normal level *-400 gpm = .062 in/min-80.4 gpm = .012 in/min**does not include mass loss due to steaming Wetwell Bottom Height CNS OIP CNSOIP ~~Page 66 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Attachment 2.1.D: SAWM SAMG Approved Languagle The following general cautions, priorities and methods will be evaluated for plant specific applicability and incorporated as appropriate into the plant specific SAMGs using administrative procedures for EPG/SAG change control process and implementation.

SAMGs are symptom based guidelines and therefore address a wide variety of possible plant conditions and capabilities while these changes are intended to accommodate those specific conditions assumed in Order EA-13-109.

The changes will be made in a way that maintains the use of SAMGs in a symptom based mode while at the same time addressing those conditions that may exist under extended loss of AC power (ELAP) conditions with significant core damage including ex-vessel core debris.Actual Approved Language that will be incorporated into site SAMG*Cautions:* Addressing the possible plant response associated with adding water to hot core debris and the resulting pressurization of the primary containment by rapid steam generation.

Addressing the plant impact that raising suppression pool water level above the elevation of the suppression chamber vent opening elevation will flood the suppression chamber vent path.Priorities:

With significant core damage and RPV breach, SAMGs prioritize the preservation of primary containment integrity while limiting radioactivity releases as follows:* Core debris in the primary containment is stabilized by water addition (SAWA)* Primary containment pressure is controlled below the Primary Containment Pressure Limit (Wetwell venting)* Water addition is managed to preserve the Mark I/Il suppression chamber vent paths, thereby retaining the benefits of suppression pool scrubbing and minimizing the likelihood of radioactivity and hydrogen release into the secondary containment (SAWM)Methods: Identify systems and capabilities to add water to the RPV or drywell, with the following generic guidance:* Use controlled injection if possible.* Inject into the RPV if possible.* Maintain injection from external sources of water as low as possible to preserve suppression chamber vent capability.

Actual language may vary by acceptable site procedure standards, but intent and structure should follow this guidance.CNS OIP CNS OiP ~~Page 67 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Attachment 3: Conceptual/Final Sketches (Conceptual sketches, as necessary to indicate equipment which is installed or equipment hookups necessary for the HCVS Actions)Sketch 1: Electrical Layout of UPS Systems (final design)Sketch 2: P&ID Layout of HCVS (final design)Sketch 3: Control Building UPS Location (final design)Sketch 4: P&ID Layout of SAWA (conceptual design)CNS OIP CNS OIP ~~Page 68 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)PANEL PL2'TRANSFER SWITCH-FLEX GENERATOR CONNECTIONS DISTRIEUTION PANEL (EE-PNL-HCVS)-EXISTING EQUIPMENT*PC-TE-2A to PC-TE-2H (SUPPRESSION POOL TEMP)* PC-PT-30B (TORUS PRESSURE(* PC-PT-4B2 (DRYWELL PRESSURE)*PC-PT-RI2B (DRYWELL PRESSURE)*PC-LRPR-I B (CONTAINMENT PARAMETERS)

PC-DPT-362 (TORUS LEVEL)NEW E CUIPMENT-* IA-PS-3 (237AVACCUM PRESSURE), P0522* IA-PS-4 (A032 PRESSUREI, P0523-EXISTING EQUIPMENT* PC-PI-2104E (TORUS PRESSURE)-- EXISTING EQUIPMENT* P C-AOV: AOD2 (I-ICVS VENT VALVE)-- N EW ECU IPME NT* PC-R-525°° PC:-TT-520 Q-ICVS TEMPERATURE), PC5IR°° PC-PT-520 (HOVE PRESSURE)

P0519-NEW EQUIPMENT* RMP-RI-520 (HOVE RADIATION INDICATOR), PCE2I=, RMP-RE-R52 (HOVE RADIATION ELEMENT)NOTES: I, LOADSIAHICH ARE POWERED RUT NOT USED RY HCVS ARE NOT INCLUDES 2. FOR PULL LOAD LIST SEE DWG 3SI0SH 1E Sketch 1: Electrical Layout of UPS Systems (Final design)CNS OIP CNS OIP ~~Page 69 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Sketch 2: P&ID Layout of HCVS (Final design)CNS OIP CNS OIP ~~Page 70 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)r-IN1RMTIN NL --M -IrwoqnM[~~rIIfl

~Sketch 3: Control Building UPS Location (Final design)CNS OIP CNSOIP ~~Page 71 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)MISSOUFR/Sketch 4: P&ID Layout of SAWA (concetpual)

CNS OIP CNS OIP ~~Page 72 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Attachment 4: Failure Evaluation Table Table 4A: Wet Well HCVS Failure Evaluation Table Failure with Alternate Action Impact on Functional C ontainment Failure Mode Failure Cause Alternate Action Venting?Failure of Vent to Valves fail to open/close No action needed, as power from dedicated UPS No Open on Demand due to loss of normal AC system provides 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months supply. Or, station power. service battery via inverter for minimum 9 hours1.041667e-4 days 0.0025 hours 1.488095e-5 weeks 3.4245e-6 months .Failure of Vent to Valves fail to open/close UPS system can supply power for 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . No Open on Demand due to loss of alternate After that, UPS system can be supplied power AC power (long term) or directly (bypassing battery charger) from FLEX depletion of dedicated provided generators.

power supply.Failure of Vent to Valves fail to open/close Recharge station service batteries with FLEX No Open on Demand due to complete loss of provided generators, considering severe accident batteries (long term). conditions.

Or, power UPS system directly (bypassing battery charger) with FLEX provided generators, and/or recharge UPS system battery.Failure of Vent to Valves fail to open/close No action needed, air can be supplied by No Open on Demand due to loss of normal accumulator tanks, which is sufficient for at least pneumatic air supply. 8 cycles of A032 valve over first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .Failure of Vent to Valves fail to open/close At ROS, open manual valves of pre-connected No Open on Demand due to loss of alternate nitrogen cylinders to air system supporting pneumatic air supply HCVS valves, replace bottles as needed with on-___________(long term). site nitrogen bottles.Failure of Vent to Valves fail to open/close Go to the ROS to supply nitrogen to the new No Open on Demand due to SOV failure. shuttle valves associated with air-operated valves PC-AOV-237AV and PC-AOV-AO32 to open the valves with pneumatic motive force.CNS OIP CNS OIP ~~Page 73 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Attachment 5: References

1. Generic Letter 89-16, Installation of a Hardened Wetwell Vent, dated September 1, 1989 2. Order EA-12-049, Mitigation Strategies for Beyond-Design-Basis External Events, dated March 12, 2012 3. Order FA- 12-050, Reliable Hardened Containment Vents, dated March 12, 2012 4. Order EA-12-051, Reliable SFP Level Instrumentation, dated March 12, 2012 5. Order EA-13-109, Severe Accident Reliable Hardened Containment Vents, dated June 6, 2013 6. JLD-ISG-2012-01, Compliance with Order EA-12-049, Mitigation Strategies for Beyond-Design-Basis External Events, dated August 29, 2012 7. JLD-ISG-2012-02, Compliance with Order EA-12-050, Reliable Hardened Containment Vents, dated August 29, 2012 8. JLD-ISG-2013-02, Compliance with Order EA-13-109, Severe Accident Reliable Hardened Containment Vents, dated November 14, 2013 9. NRC Responses to Public Comments, Japan Lessons-Learned Project Directorate Interim Staff Guidance JLD-ISG-2012-02:

Compliance with Order EA- 12 -050, Order Modifying Licenses with Regard to Reliable Hardened Containment Vents, ADAMS Accession No. ML12229A477, dated August 29, 2012 10. NET 12-06, Diverse and Flexible Coping Strategies (FLEX) Implementation Guide, Revision 0, dated August 2012 11. NET 13-02, Industry Guidance for Compliance with Order EA-1 3-1 09, Revision 1, Dated April 2015 12. NEI 13-06, Enhancements to Emergency Response Capabilities for Beyond Design Basis Accidents and Events, Revision 0, dated March 2014 13. NEI 14-01, Emergency Response Procedures and Guidelines for Extreme Events and Severe Accidents, Revision 0, dated March 2014 14. NET HCVS-FAQ-01, HCVS Primary Controls and Alternate Controls and Monitoring Locations 15. NET HCVS-FAQ-02, HCVS Dedicated Equipment 16. NET HCVS-FAQ-03, HCVS Alternate Control Operating Mechanisms

17. NET HCVS-FAQ-04, HCVS Release Point 18. NET HCVS-FAQ-05, HCVS Control and 'Boundary Valves'19. NEI HCVS-FAQ-06, FLEX AssumptionsiHCVS Generic Assumptions

20. NET HcVS-FAQ-07, Consideration of Release from Spent Fuel Pool Anomalies 21. NET HCVS-FAQ-08, HCVS Instrument Qualifications

22. NET HCVS-FAQ-09, Use of Toolbox Actions for Personnel 23. NEl White Paper HCVS-WP-01, HCVS Dedicated Power and Motive Force 24. NET White Paper HCVS-WP-02, Sequences for HCVS Design and Method for Determining Radiological Dose from HCVS Piping 25. NEI White Paper HCVS-WP-03, Hydrogen/CO Control Measures 26. NET White Paper HCVS-WP-04, Missile Evaluation for HCVS Components 30 Feet Above Grade CNS OIP CNSOIP ~~Page 74 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)27. IEEE Standard 344-2004, IEEE Recommended Practice for Seismic Qualification of Class 1E Equipment for Nuclear Power Generating Stations 28. Cooper Nuclear Station EA-12-049 (FLEX) Overall Integrated Implementation Plan, Rev 0, February 2013 29. Cooper Nuclear Station EA- 12-050 (HCVS) Overall Integrated Implementation Plan, Rev 0, February 2013 30. Cooper Nuclear Station EA-12-05 1 (SFP LI) Overall Integrated Implementation Plan, Rev 0, February 2013 31. EPRI Technical Report, Use of Modular Accident Analysis Program (MAAP) in Support of Post-Fukushima Applications, June 2013 32. 'NEDC 92-092, Review of Nutech Calculation of THPV Flow Rate and Vent Pipe Size, Nutech Caic. No.XNP033.0201

33. ISG-JLD-2012-03, Compliance with Order EA-12-05 1, Reliable Spent Fuel Pool Instrumentation, August 29, 2012 34. CNS DC 91-041, Torus Hard Pipe Vent, August 5, 1993 35. CNS Emergency Operating Procedure 5.8.2 1, PC Venting and Hydrogen Control (Less than Combustible Limits), Revision 18 36. CNS Emergency Operating Procedure 5.8.22, PC Venting and Hydrogen Control (Greater than Combustible Limits), Revision 15 37. CNS Emergency Procedure 5.3ALT-STRATEGY, Alternate Core Cooling Mitigating Strategies, Revision 36 38. Nebraska Public Power District's Second Six-Month Status Report in Response to March 12, 2012, Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond Design Basis External Events (Order Number EA-12-049), February 26, 2014 39. CNS Emergency Operating Procedure 5.8.18, Primary Containment Venting for PCPL, PSP, or Primary Containment Flooding, Revision 16 40. Cooper Nuclear Station Updated Safety Analysis Report (USAR)41. Cooper Nuclear Station Design Change Document Chapter 9 and Chapter 7 42. Cooper Nuclear Station Drawing 3617, sh. 1, Control Room Vertical Board H Arrangement

43. Cooper Nuclear Station Drawing 3621, sh. 2, Control Room Vertical Board P2 Arrangement

44. NEDC 14-026, Revision 0, Review of ERIN Calculation C122140001-1 1622 -"MAAP Analysis to Support Cooper FLEX Strategy," October 3, 2014; EC 14-027, Revision 0, Acceptance of MAAP Analysis to Support Initial FLEX Strategy, October 4, 2014.45. Cooper Nuclear Station EA-1 3-109 (HCVS) Overall Integrated Implementation Plan, Rev 0, June 30, 2014 (NRC ADAMS Document number: ML14189A415)

46. JLD-IS G-2015-01, Compliance with Phase 2 of Order EA- 13-109, Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation under Severe Accident Conditions, dated March 2015 47. Consideration of Additional Requirements for Containment Venting Systems for Boiling Water Reactors with Mark I and Mark II Containments, SECY-12-0 157, ML12344A030

48. NUJREG/CR-71 10, Vi, Ri, State-of-the-Art Reactor Consequence Analyses (SOARCA) Project: Peach Bottom Integrated Analysis, ML1 31 50A053 49. NEI HCVS-FAQ-10, Severe Accident Multiple Unit Response 50. NEI HCV S-FAQ-i11, Plant Response During a Severe Accident CNS OIP CNS OIP ~~Page 75 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)51. NEI HGCVS-FAQ-i12, Radiological Evaluations on Plant Actions Prior to HCVS Initial Use 52. NET HC VS-FAQ-i13, Severe Accident Venting Actions Validation

53. Cooper Nuclear Station Hardened Containment Venting System Phase 1 Overall Integrated Plan, Revision 1 CNS OIP CNS alp ~~Page 76 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Attachment 6:

to this Overall Integrated Implementation Plan Signi~ficant changes to this plan will be communicated to the NRC staff in the 6 Month Status Reports.The following items summarize the main changes to the design following the submission of the OIP on June 30, 2014 (Reference 45):* Rather than reusing the entire existing THIPV line, the existing THPV line will be partly demolished (from the rupture disk to the existing tie into the 24" thin-walled pipe) and a new HCVS line will be installed.

Equipment located in the section of the existing THiPV line to be demolished will be removed.* No rupture disk will be present in the new HCVS line.* The new HCVS line will entirely be routed through the Reactor Building.* The new HCVS line will have a diameter of 16" (the THPV line had a diameter of 10").* The new line will not be connected to ventilation systems such as the SGT.* The HCVS effluent will exit from the roof of the Reactor Building:

the ERP will not be used.* The existing THPV control valve, PC-AOV-AO32, will be replaced by a new control valve.* The following boundary valves will be replaced:

PC-AOV-235AV, PC-AOV-239AV.

This Overall Integrated Plan has been updated in format and content to encompass both Phase 1 and Phase 2 of Order EA-13-109.

The following items summarize the main changes to the design following the submission of the revised OIP on December 19, 2014 (Reference 53):* Vent pipe size changed to 12".* Changed method of H2 control to no longer require a purge system.* Changed method of rain/snow protection for release point.*Removed need for a vacuum breaker.Progression on the status of the existing OTP open items can be found in Attachment 7.CNS OIP CNSOIP ~~Page 77 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)Attachment 7: List of Overall Integrated Plan Open Items OWP Action Status/Comment Open Item #Determine location of HCVS ROS. Open Item closed.The Mechanical ROS will be located along the Reactor Building South exterior wall.2Evaluate accessibility of the Mechanical ROS for Open Item in progress.radiological and environmental conditions.

Address Aprlmnyesiaonfthdseae dose and temperature items for the Mechanical ROS received in the ROS from the vent line was and non-MCR locations.

FAQ-HCVS-01 (Reference calculated.

14) will be used as guidance.Evaluation of ROS accessibility for radiological and environmental remains to be determined.

Formal dose calculation at the ROS remains to be performed.

Temperature conditions at the ROS remains to be assessed.3Determine the location of the Dedicated HCVS Battery Open Item closed.transfer switch. The dedicated HCVS battery transfer switch will be located at the 903' elevation in the Control Building along the west wall.14 Determine the location of backup nitrogen bottles and Open Item in progress.evaluate the effects of radiological and temperature Nitrogen bottles will be installed and pre-constraints on their deployment, connected in the Mechanical ROS. On-site location of additional nitrogen bottles remains to be confirmed.

FLEX storage buildings are likely to be used for storage of additional nitrogen bottles. Radiological and temperature constraints during the deployment of these additional nitrogen bottles remain to be evaluated.

5 Evaluate the location of the Portable DG for Open Item in progress.accessibility under Severe Accident HCVS use.6 Confirm suppression pool heat capacity.

Open Item in progress.7 Determine which approach or combination of Open Item closed.approaches Cooper Nuclear Station (CNS) will take to Hydrogen control will be addressed using a address the control of flammable gases, clearly check valve combined with a purging demarcating the segments of vent system to which an system.approach applies.8 Identify qualification method used for HCVS Open Item in progress.instruments.

CNS OIP CNSOIP ~~Page 78 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)OIP Action Status/Comment Open Item #9Evaluate HCVS monitoring location for accessibility, Open Item in progress (see Open Item 2).habitability, staffing sufficiency, and communication capability with vent-use decision makers.10 Determine the number of required valve cycles during Open Item in progress.the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . Size the electrical and pneumatic The size of the new air-operated venting supplies accordingly.

valve remains to be determined.

Size of the!electrical supplies will be finalized during the detailed design. The size of the accumulator of the air-operated PCIV is sufficient to supply 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months of pneumatic motive force.11 Evaluate the impact of SA environmental conditions for Open Item in progress.post-24 hour actions supporting the implementation of power and pneumatic supplies.12 Determine the control document for HCVS out of Open Item in progress.service time criteria.ISE Action / ISE Section Reference Status Open Item # _____________________

________________

l Make available for NRC staff audit analysesInpoes demonstrating that HCVS has the capacity to vent the steam/energy equivalent of one percent of licensed/rated thermal power (unless a lower value is justified), and that the suppression pool and the HCVS together are able to absorb and reject decay heat, such that following a reactor shutdown from full power containment pressure is restored and then maintained below the primary containment design pressure and the primary containment pressure limit.Sections 3.2.2.1, 3.2.2.2 In progress Make available for NRC staff audit the seismic and In progress tornado missile final design criteria for the HCVS stack.Section 3.2.2.3 Make available for NRC staff audit descriptions of In progress all instrumentation and controls (existing and planned) necessary to implement this order including qualification methods.Section 3.2.2.10 CNS OIP CNSOIP ~~Page 79 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)ISE Action / ISE Section Reference Status Open Item #_________________

4 Make available for NRC staff audit a determination In progress of the number of required valve cycles during the first 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .Section 3.2.3.1 5 Make available for NRC audit the control document In progress for HCVS out of service time criteria.Section 3.4.1 6 Make available for NRC staff to audit, an evaluation In progress verifying the existing containment isolation valves, relied upon for the HCVS, will open under the maximum expected differential pressure during severe accident wetwell venting.Section 3.2.2.9 7 Make available for NRC staff audit documentation In progress that demonstrates adequate communication between the remote HCVS operation locations and HCVS decision makers during ELAP and severe accident conditions.

Section 3.2.2.5 8 Make available for NRC staff audit an evaluation of In progress temperature and radiological conditions to ensure that operating personnel can safely access and operate controls and support equipment.

Sections 3.2.1, 3.2.2.3, 3.2.2.4, 3.2.2.5, 3.2.2.10, 3.2.4.1, 3.2.4.2, 3.2.5.2, 3.2.6 9 Make available for NRC staff audit the final sizing In progress evaluation for HCVS batteries/battery charger and incorporate into FLEX DG loading calculation.

Sections 3.2.2.4, 3.2.3.1, 3.2.3.2, 3.2.4.1, 3.2.4.2, 3.2.5.1, 3.2.5.2, 3.2.6 10 Make available for NRC staff audit documentation In progress of the HCVS nitrogen pneumatic system design including sizing and location.Sections 3.2.1, 3.2.2.4, 3.2.3.1, 3.2.3.2, 3.2.4.1, 3.2.4.2, 3.2.5.1, 3.2.5.2, 3.2.6 11 Make available for NRC staff audit the descriptions In progress of local conditions (temperature, radiation and humidity) anticipated during ELAP and severe________accident for the components (valves, ___________________

CNS OIP Page 80 of 83 Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)ISE Action / ISE Section Reference Status Open Item #instrumentation, sensors, transmitters, indicators, electronics, control devices, and etc.) required for HCVS venting including confirmation that the components are capable of performing their functions during ELAP and severe accident conditions.

Sections 3.2.2.3, 3.2.2.5, 3.2.2.9, 3.2.2.10 CNS OIP CNSOIP ~~Page 81 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-109)Attachment 8: List of Acronyms AC AOV ASME AST-BDBEE BWR CAP CLTP CNS CST DBLOCA DC DDT DG DW ECCS ELAP EMC EOP EPG ERO ERP EQ GDC HCVS HCVS UPS HPCI HPV IEEE ISG MCC MCR MOV NEI NEMA NFPA NPSH NRC PC233MV UPS PRA PRV OiP, PCWV PCPL PSP RCIC Alternating Current Air-Operated Valve American Society of Mechanical Engineers Alternate Source Term Beyond-Design-Basis External Event Boiling Water Reactor Containment Accident Pressure Current Licensed Thermal Power Cooper Nuclear Station Condensate Storage Tank Design-Basis Loss Of Coolant Accident Direct Current Deflagration-to-Detonation Diesel Generator Drywell Emergency Core Cooling System Extended Loss of AC Power Electromagnetic Compatibility Emergency Operating Procedures Emergency Procedure Guidelines Emergency Response Organization Elevated Release Point Environmental Qualification General Design Criterion Hardened Containment Venting System HCVS UPS (main UPS)High Pressure Coolant Injection Hard Pipe Vent Institute of Electrical and Electronics Engineers Interim Staff Guidance Motor Control Center Main Control Room Motor-Operated Valve Nuclear Energy Institute National Electrical Manufacturers Association National Fire Protection Association Net Positive Suction Head Nuclear Regulatory Commission UPS dedicated to powering PC-MO V-233MV Probability Risk Assessment Pressure Relief Valve Overall Integrated Plan Primary Containment Isolation Valve Primary Containment Pressure Limit Pressure Suppression Pressure Reactor Core Isolation Cooling CNS OIP CNS OIP ~~Page 82 of 83 Rvso Revision 2 Cooper Nuclear Station Hardened Containment Venting System Overall Integrated Plan (EA-1 3-1 09)RH-R Residual Heat Removal ROS Remote Operating Station RPV Reactor Pressure Vessel RRC Regional Response Center SA Severe Accident SAG Severe Accident Guidelines SAMG Severe Accident Management Guidelines SADV Severe Accident Capable Drywell Vent SAWA Severe Accident Water Addition SAWM Severe Accident Water Management SAWV Severe Accident Wetwell Vent SGT Standby Gas Treatment (System)SME Seismic Margin Earthquake SFP Spent Fuel Pool SRM Staff Requirement Memorandum SOP Standard Operating Procedures SOV Solenoid-Operated Valve SW Service Water TBD To Be Determined THIPV Torus Hard Pipe Vent UPS Uninterruptible Power Supply VAC Volts Alternating Current VDC Volts Direct Current WW Wetwell CNS OIP CNSOIP ~~Page 83 of 83 Rvso Revision 2 Nebraska Public Power District Always there wvhen you need us NLS2015 137 December 21, 2015 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-000 1