RS-16-106, Fourth Six-Month Status Report for Phases 1 and 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..

Fourth Six-Month Status Report for Phases 1 and 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..

ML16182A393
Person / Time
Site:	Dresden
Issue date:	06/30/2016
From:	Kaegi G Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
EA-13-109, RS-16-106, TAC MF4462, TAC MF4463
Download: ML16182A393 (16)

Text

Amwp- Exelon Generation.

Order No. EA-13-109 RS-16-106 June 30, 2016 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Dresden Nuclear Power Station, Units 2 and 3 Renewed Facility Operating License Nos. DPR-19 and DPR-25 NRC Docket Nos. 50-237 and 50-249

Subject:

Fourth Six-Month Status Report For Phases 1 and 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)

References:

1. NRC Order Number EA-13-109, "Issuance of Order to Modify Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions," dated June 6, 2013

2. NRC Interim Staff Guidance JLD-ISG-2015-01, "Compliance with Phase 2 Order EA-13-109, Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation under Severe Accident Conditions", Revision 0, dated April 2015

3. NEI 13-02, "Industry Guidance for Compliance With Order EA-13-109, BWR Mark I & II Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions", Revision 1, dated April 2015

4. Exelon Generation Company, LLC's Answer 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 26, 2013

5. Exelon Generation Company, LLC 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 (RS-14-058)

6. Exelon Generation Company, LLC First Six-Month Status Report 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 December 17, 2014 (RS-14-302)

7. Exelon Generation Company, LLC Second Six-Month Status Report 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, 2015 (RS-15-148)

U.S. Nuclear Regulatory Commission Integrated Plan Report to EA-13-109 June 30, 2016 Page 2

8. Exelon Generation Company, LLC Phase 1 (Updated) 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), dated December 15, 2015 (RS-15-299)

9. NRC letter to Exelon Generation Company, LLC, Dresden Nuclear Power Station, Units 2 and 3 Interim Staff Evaluation Relating to Overall Integrated Plan in Response to Phase 1 of Order EA-13-109 (Severe Accident Capable Hardened Vents) JAC Nos. MF4462 and MF4463), dated February 11, 2015 On June 6, 2013, the Nuclear Regulatory Commission ("NRC" or "Commission") issued an Order (Reference 1) to Exelon Generation Company, LLC (EGC). Reference 1 was immediately effective and directs EGC to require their BWRs with Mark I and Mark 11 containments to take certain actions to ensure that these facilities have 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 (SA) conditions resulting from an Extended Loss of AC Power (FLAP). Specific requirements are outlined in Attachment 2 of Reference 1.

Reference 1 required submission of an Overall Integrated Plan (OIP) by June 30, 2014 for Phase 1 of the Order, and an OIP by December 31, 2015 for Phase 2 of the Order. The interim staff guidance (Reference 2) provides direction regarding the content of the OIP for Phase 1 and Phase 2. Reference 2 endorses industry guidance document NEI 13-02, Revision 1 (Reference 3) with clarifications and exceptions identified in Reference 2. Reference 4 provided the EGC initial response regarding reliable hardened containment vents capable of operation under severe accident conditions. Reference 5 provided the Dresden Nuclear Power Station, Units 2 and 3, Phase 1 OIP pursuant to Section IV, Condition D.1 of Reference 1. References 6 and 7 provided the first and second six-month status reports pursuant to Section IV, Condition D.3 of Reference 1 for Dresden Nuclear Power Station. Reference 8 provided the Dresden Nuclear Power Station, Units 2 and 3, Phase 1 updated and Phase 2 OIP pursuant to Section IV, Conditions D.2 and D.3 of Reference 1.

The purpose of this letter is to provide the fourth six-month update report for Phases 1 and 2, pursuant to Section IV, Condition D.3 of Reference 1, that delineates progress made in implementing the requirements of Reference 1 for Dresden Nuclear Power Station, Units 2 and 3.

The enclosed report provides an update of milestone accomplishments since the last status report, including any changes to the compliance method, schedule, or need for relief and the basis, if any. The enclosed report also addresses the NRC Interim Staff Evaluation open items contained in Reference 9.

This letter contains no new regulatory commitments. If you have any questions regarding this report, please contact David P. Helker at 610-765-5525.

U.S. Nuclear Regulatory Commission Integrated Plan Report to EA-13-109 June 30, 2016 Page 3 I declare under penalty of perjury that the foregoing is true and correct. Executed on the 30t" day of June 2016.

Respectfully submitted, 7- ,

Glen T. Kaegi Z~X Director - Licensing & Regulatory Affairs Exelon Generation Company, LLC

Enclosure:

Dresden Nuclear Power Station, Units 2 and 3 Fourth Six-Month Status Report for Phases 1 and 2 Implementation of Order EA-13-109, Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions cc: Director, Office of Nuclear Reactor Regulation NRC Regional Administrator - Region III NRC Senior Resident Inspector - Dresden Nuclear Power Station NRC Project Manager, NRR - Dresden Nuclear Power Station Mr. Raj Auluck, NRR/JLD/TSD/JCBB, NRC Mr. John P. Boska, NRR/JLD/JOMB, NRC Illinois Emergency Management Agency - Division of Nuclear Safety

Enclosure Dresden Nuclear Power Station, Units 2 and 3 Fourth Six-Month Status Report for Phases 1 and 2 Implementation of Order EA-13-109, Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (12 pages)

Enclosure Dresden Nuclear Power Station, Units 2 and 3 Fourth Six-Month Status Report for Phases 1 and 2 Implementation of Order EA-13-109, "Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions" 1 Introduction Dresden Nuclear Power Station, Units 2 and 3 developed an Overall Integrated Plan (Reference 1 in Section 8), documenting the installation of a Hardened Containment Vent System (HCVS) that provides a reliable hardened venting capability for pre-core damage and under severe accident conditions, including those involving a breach of the reactor vessel by molten core debris, in response to NRC Order EA-13-109 (Reference 2). Starting with this six month status report, updates of milestone accomplishments will be based on the combined Phases 1 and 2 Overall Integrated Plan dated December 16, 2015 (Reference 6).

Dresden Station developed an updated and combined Phases 1 and 2 Overall Integrated Plan (Reference 6), documenting:

1. The installation of a Hardened Containment Vent System (HCVS) that provides a reliable hardened venting capability for pre-core damage and under severe accident conditions, including those involving a breach of the reactor vessel by molten core debris, in response to Reference 2.

2. An alternative venting strategy that makes it unlikely that a drywell vent is needed to protect the containment from overpressure-related failure under severe accident conditions, including those that involve a breach of the reactor vessel by molten core debris, in response to Reference 2 This enclosure provides an update of milestone accomplishments since submittal of the combined Phases 1 and 2 Overall Integrated Plan including any changes to the compliance method, schedule, or need for relief/relaxation and the basis, if any.

2 Milestone Accomplishments The following milestone(s) have been completed since the development of the combined Phases 1 and 2 Overall Integrated Plan (Reference 6), and are current as of June 1, 2016.

• Major sections of 10" Vent line for Unit 3 (Lead Unit) have been routed inside the reactor building. The actual tie-in to the existing 18" vent will be done during the November 2016 outage.

• The steel tower supporting the vent lines outside the reactor building has been fabricated and its rigging and installation plans are underway.

• The nitrogen and argon piping installation is underway.

• Dose Assessment to assess impact of dose from HCVS piping on FLEX strategies has been prepared and is under final review by Exelon.

Page 1 of 12

Dresden Nuclear Power Station, Units 2 and 3 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 3 Milestone Schedule Status The following provides an update to Part 5 of the combined Phases 1 and 2 Overall Integrated Plan. It provides the activity status of each item, and whether the expected completion date has changed. The dates are planning dates subject to change as design and implementation details are developed.

Target Comments Activity Milestone Completion Status Date Phases 1 and 2 HCVS Milestone Table Submit Overall Integrated Plan June 2014 Complete Submit 6 Month Updates:

Update 1 Dec. 2014 Complete Update 2 June 2015 Complete Update 3 [Simultaneous with Phase 2 Dec. 2015 Complete OI P]

June 2016 Complete Update 4 with this submittal Update 5 Dec. 2016 Not started Update 6 June 2017 Not started Update 7 Dec. 2017 Not started Update 8 June 2018 Not started Update 9 Dec. 2018 Not started Phase 1 Specific Milestones Phase 1 U3 (Lead Unit) Modifications:

Begin Conceptual Design Sep. 2012 Complete Complete Conceptual Design Mar. 2013 Complete Begin Detailed Design Nov. 2014 Complete Complete Detailed Design and Issue Jan. 2016 Complete Page 2 of 12

Dresden Nuclear Power Station, Units 2 and 3 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Target Comments Activity Milestone Completion Status Date Phases 1 and 2 HCVS Milestone Table Modification Package Begin Online Portion of the Installation Nov. 2015 Complete Complete Online Installation Oct. 2016 Started Begin Outage Portion of the Installation Oct. 2016 Not started Complete Outage Installation Nov. 2016 Not Started Phase 1 Procedure Changes Active Operations Procedure Changes Oct. 2016 Started Developed Site Specific Maintenance Procedure Oct. 2016 Started Developed Procedure Changes Active Nov. 2016 Not Started Phase 1 Training:

Training Complete Oct. 2016 Not Started Phase 1 Completion U3 Phase 1 HCVS Implementation Nov. 2016 Not Started Submit Completion Report Jan. 2019 Not Started Phase 1 U2 (Lag Unit) Modifications:

Begin Conceptual Design Sep. 2012 Complete Complete Conceptual Design Mar. 2013 Complete Begin Detailed Design Nov. 2014 Complete Complete Detailed Design and Issue Sep. 2016 Started Modification Package Begin Online Portion of the Installation Mar. 2016 Complete Complete Online Installation Oct. 2017 Started Begin Outage Portion of the Installation Oct. 2017 Not started Page 3 of 12

Dresden Nuclear Power Station, Units 2 and 3 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Target Comments Activity Milestone Completion Status Date Phases 1 and 2 HCVS Milestone Table Complete Outage Installation Nov. 2017 Not started Phase 1 Procedure Changes Active Operations Procedure Changes Oct. 2017 Not started Developed Site Specific Maintenance Procedure Oct. 2017 Not started Developed Procedure Changes Active Oct. 2017 Not started Phase 1 Training:

Training Complete Oct. 2017 Not started Phase 1 Completion U2 Phase 1 HCVS Implementation Nov. 2017 Not started Full Site HCVS Phase 1 Implementation Nov. 2017 Not started Submit Completion Report Jan. 2018 Not started Phase 2 Specific Milestones Phase 2 U2 (Lead Unit) Modifications:

Begin Conceptual Design March 2016 Complete Complete Conceptual Design Aug. 2016 Started Begin Detailed Design Jan. 2017 Not started Complete Detailed Design and Issue Mar. 2017 Not started Modification Package Begin Online Portion of the Installation May 2017 Not started Complete Online Installation Oct. 2017 Not started Begin Outage Portion of the Installation Oct. 2017 Not started Complete Outage Installation Nov. 2017 Not started Phase 2 Procedure Changes Active i i Page 4 of 12

Dresden Nuclear Power Station, Units 2 and 3 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Target Activity Comments Milestone Completion Status Date Phases 1 and 2 HCVS Milestone Table Operations Procedure Changes Oct. 2017 Not started Developed Site Specific Maintenance Procedure Oct. 2017 Not started Developed Procedure Changes Active Oct. 2017 Not started Phase 2 Training:

Training Complete Oct. 2017 Not started Phase 2 Completion U2 Phase 2 HCVS Implementation Nov. 2017 Not started Submit Phase 1 and Phase 2 Completion Report [60 days after Unit achieves Jan. 2018 Not started compliance]

Phase 2 U3 (Lag Unit) Modifications:

Begin Conceptual Design Mar. 2016 Complete Complete Conceptual Design Aug. 2016 Started Begin Detailed Design Apr. 2017 Not started Complete Detailed Design and Issue Aug. 2017 Not started Modification Package Begin Online Portion of the Installation Oct. 2017 Not started Complete Online Installation Oct. 2018 Not started Begin Outage Portion of the Installation Oct. 2018 Not started Complete Outage Installation Nov. 2018 Not started Phase 2 Procedure Changes Active Operations Procedure Changes Oct. 2018 Not started Developed Site Specific Maintenance Procedure Oct. 2018 Not started Page 5 of 12

Dresden Nuclear Power Station, Units 2 and 3 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Target Comments Activity Milestone Completion Status Date Phases 1 and 2 HCVS Milestone Table Developed Procedure Changes Active Oct. 2018 Not started Phase 2 Training:

Training Complete Oct. 2018 Not started Phase 2 Completion U3 Phase 2 HCVS Implementation Nov. 2018 Not started Full Site HCVS Phase 2 Implementation Nov. 2018 Not started Submit Phase 1 and Phase 2 Completion Jan. 2019 Not started Report [60 days after full site compliance]

4 Changes to Compliance Method The dose impact of HCVS on FLEX strategies is being evaluated. Any changes to the compliance method will be reported in the December 2016 update.

5 Need for Relief/Relaxation and Basis for the Relief/Relaxation Dresden Station expects to comply with the Order implementation date and no relief/relaxation is required at this time.

6 Open Items from Combined Phases 1 and 2 Overall Integrated Plan and Interim Staff Evaluations The following tables provide a summary of the open items documented in the combined Phases 1 and 2 Overall Integrated Plan or the Interim Staff Evaluation (ISE) and the status of each item.

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Dresden Nuclear Power Station, Units 2 and 3 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Combined Phases 1 and 2 OIP Open Items Status Item Phase 1 Open Items 0I-1 Confirm that at least 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> battery coping Closed to ISE Open Item number 1.

time is available.

0I-2 Determine actions to enable wetwell (WW) Closed to ISE Open Item number 2.

venting following a flooding around the torus.

0I-3 Determine how Motive Power and/or HCVS Closed to ISE Open Item number 3.

Battery Power will be disabled during normal operation.

0I-4 Confirm that the Remote Operating Station Closed to ISE Open Item number 12.

(ROS) will be in an accessible area following a Severe Accident (SA).

0I-5 Confirm diameter on new common HCVS Closed to ISE Open Item number 5.

Piping.

0I-6 Confirm suppression pool heat capacity. Closed to ISE Open Item number 6.

0I-7 Determine the approach for combustible Closed to ISE Open Item number 7.

gases.

0I-8 Provide procedures for HCVS Operation. Closed to ISE Open Item number 18.

0I-9 Perform radiological evaluation for Phase 1 Started vent line impact on ERO response actions.

Item Phase 2 Open Items 0I-1 Determine SAWA flow control. Not started 0I-2 Resolve location of the FLEX DG to Started mitigate radiological consequences during severe accident conditions.

OI-3 Validate time-line for Reactor Building hose Not started connections does not exceed 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />.

Item Phase 1 Interim Staff Evaluation Status

1. Open Items ISE-1 Make available for NRC staff audit Complete documentation confirming that at least 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> battery coping time is available. EC 391973 is available for NRC review on the ePortal.

ISE-2 Make available for NRC staff audit Started documentation that confirms the ability to Page 7 of 12

Dresden Nuclear Power Station, Units 2 and 3 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Item Phase 1 Interim Staff Evaluation Status in Open Items operate HCVS following flooding around the suppression pool.

I S E-3 Make available for NRC staff audit Complete with this submittal.

documentation of a method to disable HCVS during normal operation to provide HCVS design precludes inadvertent assurances against inadvertent operation actuation of the system through passive that also minimizes actions to enable design features. The HCVS vent pipe has RCVS operation following an ELAP. been designed with two PCIVs, in series, in compliance with GDC-56. The PCIVs have independent actuation trains, thereby precluding inadvertent actuation by a single component failure or mis-alignment.

Each PCIV isolates the vent line through its normally held closed actuator spring. A rupture disk in the vent line downstream of the PCIVs preserves the secondary containment boundary. Furthermore, to prevent inadvertent opening, the PCIVs are isolated from their motive force supply by two locked closed manual valves and require remote manual operation of a key-lock on the control switch at the primary operating station. Similarly, purge gas supply is isolated from the vent line by two locked closed manual valves and requires remote manual operation of a key-lock on the control switch at the primary operating station. Since there are no interfacing systems downstream of the PCIVs, no inadvertent venting cross flow can occur.

Details on the configuration of the vent line PCIVs can be found in EC 401069, Design Considerations Summary (DCS).

Sections 4.1.4.1, 4.1.4.1.5 and 4.1.27.

Based on the details in the EC, NEI requirements 4.1.2.1 and 4.2.1, to prevent inadvertent actuation of the system, are met.

EC 401069 is available for NRC review on the ePortal.

I S E-4 Make available for NRC staff audit the Started seismic and tornado missile final design criteria for the HCVS stack.

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Dresden Nuclear Power Station, Units 2 and 3 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Item Phase 1 Interim Staff Evaluation Status

1. Open Items ISE-5 Make available for NRC staff audit Complete with this submittal.

documentation of the licensee design effort to confirm the diameter on the new Calculation DRE15-0046 uses a RELAP5 common HCVS piping. model to determine that a 10-inch diameter vent is sufficient to remove 1 %

reactor thermal power.

Calculation DRE15-0046 is available for NRC review on the ePortal.

ISE-6 Make available for NRC staff audit Complete with this submittal.

analyses demonstrating that HCVS has the capacity to vent the steam/energy Calculation DRE15-0046 uses a RELAP5 equivalent of one percent of licensed/rated model to determine that a 10-inch thermal power (unless a lower value is diameter vent is sufficient to remove 1 %

justified), and that the suppression pool reactor thermal power. The steady state and the HCVS together are able to absorb venting capacity of the Dresden HCVS and reject decay heat, such that following was determined at a torus vapor space a reactor shutdown from full power pressure of 47 psig, which corresponds to containment pressure is restored and then the PCPL for the torus filled with water. At maintained below the primary containment a torus pressure of 47 psig, the HCVS can design pressure and the primary vent 111,071 Ibm /hr of steam. At 1 %

containment pressure limit. reactor thermal power the required vent capacity is 110,381 Ibm/hr. Therefore, Requirement 1.2.1 of Attachment 2 to NRC Order EA-13-109 is met.

Calculation DRE15-0046 is available for NRC review on the ePortal.

ISE-7 Provide a description of the final design of Started the HCVS to address hydrogen detonation and deflagration. Dresden design will install an argon purge system to address hydrogen detonation and deflagration requirements of NEI 13-02 Rev. 1 and consistent with HCVS-WP-

03. Argon purge system design is in progress.

ISE-8 Make available for NRC staff audit Started documentation of a determination of seismic adequacy for the ROS location.

ISE-9 Make available for NRC staff audit Complete with this submittal.

documentation that demonstrates adequate communication between the FSG-39, FLEX Communications Options, remote RCVS operation locations and discusses the available Onsite HCVS decision makers during ELAP and communications. Communications may Page 9 of 12

Dresden Nuclear Power Station, Units 2 and 3 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Item Phase 1 Interim Staff Evaluation Status

1. Open Items severe accident conditions. be performed using the installed sound powered headset system within the power block and 800 Mhz radios in the talkaround mode. Public Address announcements are made by Nuclear Security Officers using hand-held bullhorns.

Offsite communications will utilize hand-held satellite phones staged in the Control Room and Technical Support Center.

Battery chargers for portable communications equipment are stored in a robust structure. Upon initiation of the ELAP, the FLEX Diesel Generator can power the battery chargers.

FSG-39 is available for NRC review on the ePortal.

ISE-10 Provide a description of the strategies for Complete with this submittal.

hydrogen control that minimizes the potential for hydrogen gas migration and As described in the OIP, the HCVS torus ingress into the reactor building or other vent path in each Dresden unit, starting at buildings. and including the downstream Primary Containment Isolation Valve (PCIV), will be a dedicated HCVS flow path. There are no interconnected systems downstream of the downstream dedicated HCVS PCIV.

Interconnected systems are upstream of the downstream HCVS PCIV and are isolated by normally shut, fail shut PCIVs which, if open, would shut on an ELAP.

There is no shared HCVS piping between the two units. As a result, the potential for hydrogen gas migration and ingress into the reactor building or other buildings is minimized.

ISE-11 Provide descriptions of design details that Complete with this submittal.

minimize unintended cross flow of vented fluids within a unit and between units on As described in ISE item 10 response, the site. Dresden's piping layout minimizes the possibility of cross flow of vented fluids within a unit and between the two units.

ISE-12 Make available for NRC staff audit an Started evaluation of temperature and radiological conditions to ensure that operating Page 10 of 12

Dresden Nuclear Power Station, Units 2 and 3 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Item Phase 1 Interim Staff Evaluation Status

1. Open Items personnel can safely access and operate controls and support equipment.

ISE-13 Make available for NRC staff audit the Started final sizing evaluation for HCVS batteries/battery charger including incorporation into FLEX DG loading calculation.

ISE-14 Make available for NRC staff audit Started documentation of the HCVS nitrogen pneumatic system design including sizing and location.

ISE-15 Make available for NRC staff audit Started descriptions of all instrumentation and controls (existing and planned) necessary Instrument design is in progress.

to implement this order including qualification methods.

ISE-16 Make available for NRC staff audit the Started descriptions of local conditions (temperature, radiation and humidity) Component location design is in progress.

anticipated during ELAP and severe The HCVS primary control panel will be accident for the components (valves, located in the Main Control Room (MCR).

instrumentation, sensors, transmitters, indicators, electronics, control devices, etc.) required for HCVS venting including confirmation that the components are capable of performing their functions during ELAP and severe accident conditions.

ISE-17 Make available for NRC staff audit Started documentation of an evaluation verifying the existing containment isolation valves, The existing containment isolation valves relied upon for the HCVS, will open under are being evaluated for their performance the maximum expected differential under wetwell venting conditions.

pressure during BDBEE and severe accident wetwell venting.

ISE-18 Make available for NRC staff audit Not started procedures for HCVS operation.

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Dresden Nuclear Power Station, Units 2 and 3 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Item Phase 2 Interim Staff Evaluation Status

1. Open Items Phase 2 ISE not received 7 Interim Staff Evaluation Impacts There are no potential impacts to the Interim Staff Evaluation(s) identified at this time.

8 References The following references support the updates to the combined Phases 1 and 2 Overall Integrated Plan described in this enclosure.

1. Dresden Nuclear Power Station, Units 2 and 3, 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.

2. 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.

3. NEI 13-02, "Industry Guidance for Compliance with NRC Order EA-13-109, To Modify Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions," Revision 1, dated April 2015.

4. NRC Interim Staff Guidance JLD-ISG-2013-02, "Compliance with Order EA-13-109, Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions," Revision 0, dated November 2013 (Accession No. ML13304B836).

5. NRC Endorsement of industry "Hardened Containment Venting System (HCVS) Phase 1 Overall Integrated Plan Template (EA-13-109) Rev 0" (Accession No. ML14128A219).

6. Dresden Nuclear Power Station, Units 2 and 3, Combined Phase 1 and 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), dated December 16, 2015.

7. NRC Interim Staff Guidance JLD-ISG-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," Revision 0, dated April 2015 (Accession No. ML15104A118).

8. NRC Order Number EA-12-050, Order Modifying Licenses with Regard to Reliable Hardened Containment Vents, dated March 12, 2012.

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