ML15225A158

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Issuance of Amendment for Temporary Restoration of the Borated Water Storage Tank Cleanup and Recirculation Operation (TAC No. 6504)
ML15225A158
Person / Time
Site: Three Mile Island Constellation icon.png
Issue date: 10/01/2015
From: Robert Gladney
Plant Licensing Branch 1
To: Bryan Hanson
Exelon Nuclear
Gladney R, NRR/DORL/LPLI-2, 415-1022
References
TAC MF6504
Download: ML15225A158 (21)


Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 October 1, 2015 Mr. Bryan C. Hanson President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555

SUBJECT:

THREE MILE ISLAND NUCLEAR STATION, UNIT 1 - ISSUANCE OF AMENDMENT FOR TEMPORARY RESTORATION OF THE BORATED WATER STORAGE TANK CLEANUP AND RECIRCULATION OPERATION (TAC NO. 6504)

Dear Mr. Hanson:

The Commission has issued the enclosed Amendment No. 289 to Renewed Facility Operating License No. DPR-50 for Three Mile Island Nuclear Station, Unit 1 (TMI), in response to your application dated July 23, 2015, as supplemented by letters dated July 28, 2015, and August 25, 2015.

The amendment revises TMI Technical Specification 3.3.1.1, "Injection Systems," to allow for the temporary operation of the borated water storage tank under administrative and design controls while connected to seismic Class II piping. This change would support necessary cleanup and surveillance activities associated with the TMI Fall 2015 Refueling Outage and Fuel Cycle 21 operation.

A copy of the related safety evaluation is also enclosed. Notice of Issuance will be included in the Commission's Biweekly Federal Register Notice.

Sincerely,

~I ;I ~,#'-ffi Robert L. Gladney, Project Manager ~

Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-289

Enclosures:

1. Amendment No. 289 to Renewed DPR-50
2. Safety Evaluation cc w/enclosures: Distribution via Listserv

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 EXELON GENERATION COMPANY. LLC DOCKET NO. 50-289 THREE MILE ISLAND NUCLEAR STATION. UNIT 1 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 289 Renewed License No. DPR-50

1. The Nuclear Regulatory Commission (the Commission) has found that:

A. The application for amendment by Exelon Generation Company, LLC (Exelon Generation Company), dated July 23, 2015, as supplemented by letters dated July 28, 2015, and August 25, 2015, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended {the Act), and the Commission's rules and regulations set forth in 10 CFR Chapter I; B. The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C. There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commission's regulations; D. The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E. The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.

Enclosure 1

2. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.c.(2) of Renewed Facility Operating License No. DPR-50 is hereby amended to read as follows:

(2) Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No. 289, are hereby incorporated in the license. The Exelon Generation Company shall operate the facility in accordance with the Technical Specifications.

3. This license amendment is effective as of its date of issuance and shall be implemented within 7 days.

FOR THE NUCLEAR REGULA TORY COMMISSION Douglas A. Broaddus, Chief Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

Attachment:

Changes to the Technical Specifications and Facility Operating License Date of Issuance: October 1, 2015

ATTACHMENT TO LICENSE AMENDMENT NO. 289 RENEWED FACILITY OPERATING LICENSE NO. DPR-50 DOCKET NO. 50-289 Replace the following page of the Facility Operating License with the revised page. The revised page is identified by amendment number and contains marginal lines indicating the areas of change.

Remove Insert 4 4 Replace the following page of the Appendix A Technical Specifications with the attached revised pages. The revised pages are identified by amendment number and contain marginal lines indicating the area of change.

Remove Insert 3-21 3-21 3-21a

(2) Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No. 289, are hereby incorporated in the license. The Exelon Generation I Company shall operate the facility in accordance with the Technical Specifications.

(3) Physical Protection Exelon Generation Company shall fully implement and maintain in effect all provisions of the Commission-approved physical security, training and qualification, and safeguards contingency plans including amendments made pursuant to provisions of the Miscellaneous Amendments and Search Requirements revisions to 10 CFR 73.55 (51 FR 27817 and 27822), and the authority of 10 CFR 50.90 and 10 CFR 50.54(p ). The combined set of plans 1, submitted by letter dated May 17, 2006, is entitled: 'Three Mile Island Nuclear Station Security Plan, Training and Qualification Plan, and Safeguards Contingency Plan, Revision 3." The set contains Safeguards Information protected under 10 CFR 73.21.

Exelon Generation Company shall fully implement and maintain in effect all provisions of the Commission-approved cyber security plan (CSP), including changes made pursuant to the authority of 10 CFR 50.90 and 10 CFR 50.54(p). The Exelon Generation Company CSP was approved by License Amendment No. 275.

(4) Fire Protection Exelon Generation Company shall implement and maintain in effect all provisions of the Fire Protection Program as described in the Updated FSAR for TMl-1.

Changes may be made to the Fire Protection Program without prior approval by the Commission only if those changes would not adversely affect the ability to achieve and maintain safe shutdown in the event of a fire. Temporary changes to specific fire protection features which may be necessary to accomplish maintenance or modifications are acceptable provided that interim compensate measures are implemented.

(5) The licensee shall implement a secondary water chemistry monitoring program to inhibit steam generator tube degradation. This program shall include:

a. Identification of a sampling schedule for the critical parameters and control points for these parameters;
b. Identification of the procedures used to measure the values of the critical parameters;
c. Identification of process sampling points;
d. Procedure for the recording and management of data; 1

The Training and Qualification Plan and Safeguards Contingency Plan are Appendices to the Security Plan.

Amendment No. 289 Renewed Operating License No. DPR-50

3.3 EMERGENCY CORE COOLING, REACTOR BUILDING EMERGENCY COOLING AND REACTOR BUILDING SPRAY SYSTEMS Applicability Applies to the operating status of the emergency core cooling, reactor building emergency cooling, and reactor building spray systems.

Objective To define the conditions necessary to assure immediate availability of the emergency core cooling, reactor building emergency cooling and reactor building spray systems.

Specification 3.3.1 The reactor shall not be made critical unless the following conditions are met:

3.3.1.1 Injection Systems

a. The borated water storage tank (BWST) shall contain a minimum of 350,000 gallons of water having a minimum concentration of 2,500 ppm boron at a temperature not less than 40°F. If the boron concentration or water temperature is not within limits, restore the BWST to OPERABLE within 8 hrs. If the BWST volume is not within limits, restore the BWST to OPERABLE within one hour. Specification 3.0.1 applies.

NOTES:

1. The BWST piping may be unisolated from seismic Class II Cleanup path piping for a total duration of not more than 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> prior to the scheduled start of the Fall 2015 Refueling Outage and for a total duration of not more than 1440 hours0.0167 days <br />0.4 hours <br />0.00238 weeks <br />5.4792e-4 months <br /> during the following Fuel Cycle 21 operation under administrative and design controls for filtration and/or demineralization of the tank contents.
2. The BWST piping may be unisolated from seismic Class 11 Recirculation path piping for not more than 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> per week to perform weekly (and after each makeup) BWST boron concentration surveillance testing under administrative and design controls until the end of Fuel Cycle 21 operation.
b. Two Makeup and Purification (MU)/High Pressure Injection (HPI) pumps are OPERABLE in the engineered safeguards mode powered from independent essential buses. Specification 3.0.1 applies.
c. Two decay heat removal pumps are OPERABLE. Specification 3.0.1 applies.
d. Two decay heat removal coolers and their cooling water supplies are OPERABLE.

(See Specification 3.3.1.4) Specification 3.0.1 applies.

e. Two BWST level instrument channels are OPERABLE.
f. The two reactor building sump isolation valves (DH-V-6A/B) shall be remote-manually OPERABLE. Specification 3.0.1 applies.

3-21 Amendment No. 24,W,+.78,2G3,~.~.2-2+. Corrected by letter dtd July 8, 1QQQ

~. 289

3.3 EMERGENCY CORE COOLING. REACTOR BUILDING EMERGENCY COOLING AND REACTOR BUILDING SPRAY SYSTEMS (Contd.)

g. MU Tank (MUT) pressure and level shall be maintained within the Unrestricted Operating Region of Figure 3.3-1.
1) With MUT conditions outside of the Unrestricted Operating Region of Figure 3.3-1, restore MUT pressure and level to within the Unrestricted Operating Region within 72 hrs. Specification 3.0.1 applies.
2) Operation with MUT conditions within the Prohibited Region of Figure 3.3-1 is prohibited. Specification 3.0.1 applies.

3.3.1.2 Core Flooding System

a. Two core flooding tanks (CFTs) each containing 940 +/- 30 ft 3 of borated water at 600 +/- 25 psig shall be available. Specification 3.0.1 applies.

3-21a Amendment No. ~,~,+78,~,244,~,22+. Corrected by letter dtd July 8, 1999

~,289

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 289 TO RENEWED FACILITY OPERATING LICENSE NO. DPR-50 EXELON GENERATION COMPANY. LLC THREE MILE ISLAND NUCLEAR STATION. UNIT 1 DOCKET NO. 50-289

1.0 INTRODUCTION

By application dated July 23, 2015, as supplemented by letters dated July 28, 2015, and August 25, 2015 (Agencywide Documents Access and Management System (ADAMS)

Accession Nos. ML15204A843, ML15209A960, and ML15237A417, respectively), Exelon Generation Company, LLC (Exelon, the licensee), submitted a license amendment request (LAR) proposing changes to the technical specifications (TSs) for Three Mile Island Nuclear Station, Unit 1 (TMI).

The requested amendment concerns the operability of the borated water storage tank (BWST).

The proposed amendment would revise TMI TS 3.3.1.1, "Injection Systems," to address operability and seismic concerns by allowing the limiting condition for operation (LCO) to be met even if the BWST piping is not isolated from seismic class II piping for a limited time period.

This change would support necessary cleanup and surveillance activities associated with the TMI Fall 2015 Refueling Outage and Fuel Cycle 21 operation.

The supplements dated July 28, 2015, and August 25, 2015, provided additional information that clarified the application, did not expand the scope of the application as originally noticed, and did not change the U.S. Nuclear Regulatory Commission (NRG) staff's original proposed no significant hazards consideration determination as published in the Federal Register on August 7, 2015 (80 FR 47529) and subsequent notice of September 1, 2015 (80 FR 52807).

2.0 BACKGROUND

The BWST contains greater than 350,000 gallons of water with a boron concentration greater than 2,500 parts per million. The tank is governed by TS 3.3.1.1, which requires it to be operable when the reactor is critical. The design functions of the tank include providing borated water for the following applications: high pressure injection, low pressure injection, reactor building spray, emergency boration, refueling transfer canal filling, and reactor coolant system Enclosure 2

makeup during cooldown. The BWST water used to fulfill these design functions must be cleaned periodically for both radiological and operational considerations. Specifically, cleaning the water minimizes the radiological dose rates to personnel working near the tank, maintains optical clarity of the refueling water, and minimizes the radiological dose rates for workers during refueling activities.

The BWST cleanup operation processes water through filter and demineralizer equipment via a flow-path that includes portions of the spent fuel pool (SFP) and liquid waste disposal (WDL) systems. The WDL system is designated as seismic Class II, and it is normally isolated from the BWST by two manual-isolation valves. When this flow-path is needed, the isolation valves are opened, placing the BWST in communication with the WDL system. This evolution is typically performed during power operations when the BWST is required to be operable in accordance with TS 3.3.1.1. On January 26, 2012, the NRC issued Information Notice (IN) 2012-01, "Seismic Considerations - Principally Issues Involving Tanks" (ADAMS Accession No. ML11292A175), which highlighted examples of pressurized-water reactor nuclear stations inappropriately using non-seismic piping to clean-up their refueling water storage tank (RWST) contents. (It should be noted that the RWST is a tank with an analogous design basis as the BWST.) IN 2012-01 brought into question the acceptability of the TMI cleanup operation, since the flow-path through the WDL system is designated as seismic Class II as opposed to the seismic Class I designation of the BWST.

BWST cleanup operations were briefly discontinued subsequent to the issuance of IN 2012-01.

However, based on the results of a licensee evaluation, the processing activity was resumed until a Severity Level IV, non-cited violation was issued on May 14, 2014, via Inspection Report 5000289/2014002 (ADAMS Accession No. ML14134A500). The following two issues were identified in the inspection report: (1) alignment of the BWST to non-seismically (i.e.,

seismic Class II or below) qualified pipe is contrary to the licensing basis, and (2) NRC approval is likely needed for operator actions that were credited to close manual valves isolating the BWST from the non-seismic piping in the event of an earthquake. The licensee responded to the violation by discontinuing the use of the flow-path.

The NRC also issued Task Interface Agreement (TIA) 2015-01, "Assessment of Three Mile Island Nuclear Station's Use of a Non-Seismic Qualified Cleanup Path for the Borated Water Storage Tank" (ADAMS Accession No. ML15175A300), which assessed whether operation of the BWST connected to non-seismic piping was within the TMI licensing basis. The TIA concluded that (1) it was contrary to the TMI licensing basis to connect the BWST to non-seismic piping during its TS mode of applicability, and (2) this configuration renders the BWST inoperable.

In addition to the cleanup operation, the BWST boron concentration surveillance testing required by TS Table 4.1-3, Item 2, is impacted by the seismic Class II connections to the BWST. As a compensatory measure, the licensee is currently entering the 72-hour LCO action statement for TS 3.3.2 to use one of the emergency core cooling system (ECCS) pumps to provide adequate BWST recirculation for boron sampling. Use of the ECCS sampling path ensures that the BWST is connected to seismic Class I piping during cleanup and recirculation.

In response to the issues discussed above, the licensee is requesting to amend its TS and provide, for the period before and during Fuel Cycle 21, the permission needed to use seismic Class II piping to (1) clean up the water in the BWST, and (2) perform the BWST boron concentration surveillance testing (i.e., boron sampling). The cleanup operation will consist of the flow-path through the SFP and WDL systems that was previously used. The surveillance testing will utilize a recirculation path that is the same as the cleanup path, except the cation demineralizers are bypassed.

This LAR is required to support activities before and after the Fall 2015 Refueling Outage and throughout Fuel Cycle 21 operation. The specifics of the proposed amendment include the addition of two notes to TS 3.3.1.1 (a), which state the following:

Note 1 - The BWST piping may be unisolated from seismic Class II Cleanup path piping for a total duration of not more than 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> prior to the scheduled start of the Fall 2015 Refueling Outage and for a total duration of not more than 1440 hours0.0167 days <br />0.4 hours <br />0.00238 weeks <br />5.4792e-4 months <br /> during the following Fuel Cycle 21 operation under administrative and design controls for filtration and/or demineralization of the tank contents.

Note 2 -The BWST piping may be unisolated from seismic Class II Recirculation path piping for not more than 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> per week to perform weekly (and after each makeup) BWST boron concentration surveillance testing under administrative and design controls until the end of Fuel Cycle 21 operation.

BWST cleanup and surveillance testing contribute to the safe operation of the plant. The times chosen by the licensee to perform these activities are provided in Note 1 and Note 2. The TS notes proposed by the LAR represent a relaxation from the TS 3.3.1.1 (a) requirements, which in their current form do not allow the BWST to connect to a seismic Class II system during the mode of applicability of the TS (i.e., TS 3.3.1.1 (a) is applicable when the reactor is critical). The safety concern with operating the plant in this manner is that a safe-shutdown earthquake (SSE) could render the BWST inoperable by challenging the structural and pressure boundary integrity of the cleanup and recirculation paths. If the connected seismic Class II piping and equipment lost integrity during a seismic event, the ability of the BWST to maintain its TS volume requirement (i.e., minimum of 350,000 gallons) would be jeopardized. Without the TS prescribed amount of water, the BWST would not be able to perform its specified safety function in an accident scenario (e.g., supply borated water to ECCS in the event of a loss-of-coolant accident).

The licensee asserts that if this LAR is not approved, then the BWST water will not be cleaned up prior to the refueling outage in the fall of 2015, which will result in radiological dose issues having to be addressed. Based on the current isotopic level of Cobalt-58, and absent significant shielding modifications, estimated dose to the refuel workers is between 3 and 4 roentgen equivalent man (rem), as compared to 1 rem during the previous outage, assuming the BWST is not cleaned up. The dose impact to the reactor vessel 10-year inservice inspection (ISi) workers is an additional 2 to 3 rem, and additional exposure to workers outside the reactor building in the yard area while loading and unloading outage equipment is expected to be approximately 1 to 2 rem. Also, if the TS are not amended, the licensee will have to repeatedly (i.e., weekly) enter LCO action statement for TS 3.3.2 during performance of the BWST boron concentration surveillance.

The licensee's stated intent is for this amendment to be an interim measure until a permanent solution is identified.

3.0 REGULATORY AND TECHNICAL EVALUATIONS Title 10 of the Code of Federal Regulations (10 CFR) Part 50, "Domestic Licensing of Production and Utilization Facilities," establishes the fundamental regulatory requirements for nuclear power plants.

Under 10 CFR 50.90, whenever a holder of an operating license desires to amend the license, an application for an amendment must be filed with the Commission fully describing the changes desired, and following as far as applicable, the form prescribed for original applications. 10 CFR 50.36(a)(1) requires an applicant for an operating license to include technical specifications (TS), along with a summary statement of the bases or reasons for such specifications. The proposed TS must include LCOs, which are the lowest functional capability or performance levels of equipment required for safe operation of the facility. When an LCO of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial action permitted by the technical specifications until the condition can be met.

Per 10 CFR 50.92(a), in determining whether an amendment to a license will be issued to the applicant, the Commission will be guided by the considerations which govern the issuance of initial licenses to the extent applicable and appropriate. The license includes TS derived from the analyses and evaluation included in the safety analysis report submitted as part of the application for an initial license. The construction permit for TMI was issued by the Atomic Energy Commission (AEC) on May 18, 1968, and an operating license was issued on April 19, 1974. The preliminary safety analysis report for the construction permit was based on the proposed General Design Criteria (GDC) published by the AEC in the Federal Register (32 FR 10213) on July 11, 1967 (hereinafter referred to as "AEC GDC"). The AEC published the final rule that added 10 CFR 50, Appendix A, "General Design Criteria for Nuclear Power Plants,"

(hereinafter referred to as "GDC"), in the Federal Register (36 FR 3255) on February 20, 1971, which was before the operating license was issued. However, as described in an NRC Staff Requirement Memorandum (SRM) from S.J. Chilk to J.M. Taylor, "SECY-92-223 - Resolution of Deviations Identified During the Systematic Evaluation Program," dated September 18, 1992 (ADAMS Accession No. ML003763736), the Commission decided not to apply the final GDC to plants with construction permits issued prior to May 21, 1971, which included TMI.

TMI plant-specific principal design criteria are described in Chapter 1 of the Updated Final Safety Analysis Report (UFSAR). Two GDCs were utilized in the evaluations found in the following sections. These GDC are listed below, along with the applicable part of the similar AEC GDC with the similar requirement.

10 CFR Part 50, Appendix A, GDC 2, "Design Bases for Protection Against Natural Phenomena," which states, in part:

Structures, systems, and components important to safety shall be designed to withstand the effects of natural phenomena such as earthquakes, tornadoes, hurricanes, floods, tsunami, and seiches without the loss of the capability to perform their safety functions.

GDC 2 is similar to TM l's AEC GDC Criterion 2:

Those systems and components of Reactor Building facilities which are essential to the prevention of accidents which could affect the public health and safety or to mitigation of their consequences shall be designed, fabricated, and erected to performance standards that will enable the facility to withstand, without loss of the capability to protect the public, the additional forces that might be imposed by natural phenomena such as earthquakes, tornadoes, flooding conditions, winds, ice, and other local site effects. [TMI UFSAR, Section 1.4.2, "Criterion 2 -

Performance Standards (Category A)"]

10 CFR Part 50, Appendix A, GDC 35, "Emergency Core Cooling," which states:

A system to provide abundant emergency core cooling shall be provided. The system safety function shall be to transfer heat from the reactor core following any loss of reactor coolant at a rate such that (1) fuel and clad damage that could interfere with continued effective core cooling is prevented and (2) clad metal-water reaction is limited to negligible amounts.

GDC 35 is similar to TMl's AEC GDC Criterion 44:

At least two emergency core cooling systems, preferably of different design principles, each with a capability for accomplishing abundant emergency core cooling, shall be provided. Each emergency core cooling system and the core shall be designed to prevent fuel and clad damage that would interfere with the emergency core cooling function and to limit the clad metal-water reaction to negligible amounts for all sizes of breaks in the reactor coolant pressure boundary, including the double-ended rupture of the largest pipe. [TMI UFSAR, Section 1.4.44, "Criterion 44 - Emergency Core Cooling Systems Capability (Category A)"]

In this review, and to maintain consistency with the NRC staff's standard review plans, the NRC staff cites the 10 CFR 50, Appendix A GDC, rather than the AEC GDC.

The NRC staff issued IN 2012-01 on January 26, 2012, to inform licensees to consider actions, as appropriate, to address seismic concerns at their sites.

3.1 Mechanical and Civil Engineering Evaluation 3.1.1 Regulatory Evaluation - Mechanical and Civil Engineering As previously stated, the LAR proposes to allow for the temporary connection of the BWST to seismic Class II piping for cleanup and recirculation. The staff's concern is that the BWST may not have enough water to perform its safety function due to degraded seismic Class II piping after a seismic event. Section 5.4.4 of the TMI UFSAR describes piping design criteria and the allowable piping stress for seismic conditions.

The NRC staff's assessment of the LAR in the areas of mechanical and civil engineering considered the regulatory requirements of GDC 2 as described above. As such, the NRC staff's review primarily focused on verifying the design and licensing requirements related to the structural and pressure boundary integrity of SSCs affected by the proposed LAR. This, in turn, provides reasonable assurance that continued compliance with the applicable regulations will be maintained.

3.1.2 Technical Evaluation - Mechanical and Civil Engineering The NRC staff's review in the areas of mechanical and civil engineering covers the structural and pressure boundary integrity of the BWST to seismic Class II piping connection systems.

Specifically, the review is focused on the licensee's piping and component stress analysis performed under safe-shutdown earthquake (SSE) conditions.

The staff reviewed the licensee's assessment listed in Attachment 4, "Technical Evaluation to Assess BWST Cleanup Path Pipe Stress," of the LAR. The licensee's analysis of the BWST cleanup piping included all design inputs, references, assumptions, method of analysis, analysis results (including maximum stresses), valve accelerations, seismic displacement, and support loads.

The licensee performed the piping analysis for deadweight, pressure, and SSE loading conditions.

The staff confirmed that the SSE stresses and loads are combined in accordance with Section 5.4.4, "Piping Design Criteria," of the TMI UFSAR. The staff also confirmed that the licensee's SSE response spectra analysis used American Society of Mechanical Engineers Boiler & Pressure Vessel Code Case N-411-1 damping values that are consistent with Section 5.2.1.2.11, "Earthquake Load," of the TMI UFSAR.

The stress analysis showed that all piping stresses are below allowable values and are acceptable. Based on the results and analysis method, the staff confirmed that the seismic evaluation concluded that the cleanup and recirculation seismic Class II piping paths would maintain pressure boundary integrity during an SSE. Also, as an additional defense-in-depth (DID) action, the licensee will implement administrative controls using proceduralized operator manual action during a seismic event. The manual action can take the BWST off the cleanup and recirculation operation to isolate it from seismic Class II piping.

On the basis that the applicant's SSE analysis determined that the structural and pressure boundary integrity of the BWST will be maintained during cleanup and recirculation operation, the staff agrees that the BWST will remain operable throughout an SSE.

3.1.3 Conclusion - Mechanical and Civil Engineering Based on its review of the licensee's SSE evaluation results and the information presented in the LAR, the NRC staff concludes that the cleanup and recirculation seismic Class II piping paths would maintain the structural and pressure boundary integrity of the BWST during an SSE and that the design requirements of GDC 2 will not be impacted. Therefore, the staff

determines that temporary restoration of the BWST cleanup and recirculation operation is acceptable 3.2 Human Factors Evaluation 3.2.1 Regulatory Evaluation - Human Factors NRC human factors reviews address programs, procedures, training, plant design features, and operator manual actions related to operator performance during normal and accident conditions.

The NRC staff conducted a human factors evaluation to confirm that operator performance would not be adversely affected as a result of changes to the TMI TSs and the associated operator manual actions. The review was based on the following regulatory guidance:

  • NUREG-0800, "Standard Review Plan," Chapter 18, "Human Factors Engineering,"

Revision 2

  • NUREG-1764, "Guidance for the Review of Changes to Human Actions," Revision 1 3.2.2 Technical Evaluation - Human Factors The following sections evaluate the proposed operator actions described in the LAR, as well as relevant additional clarifications in the July, 28, 2015, supplement.

3.2.2.1 Description of Operator Actions and Their Safety Significance - Human Factors The licensee describes how operator actions are used to isolate seismic Class II portions of the BWST system in the case of a seismic event. Additionally, the licensee has performed analyses indicating that the BWST is capable of performing its safety-related functions in the case of an SSE without operator intervention (i.e., the seismic Class II piping pathways will maintain integrity during an SSE). Operator manual actions are used to add additional DID and are not relied upon to preserve the BWST safety functions.

Existing procedures direct operators to implement steps in OP-TM-AOP-003, "Earthquake,"

when ground motion is identified at the plant. (Note: Subsequent confirmation of an operating-basis earthquake (OBE) or SSE is not required before taking these actions, thus helping to ensure a timely response.) Procedure OP-TM-AOP-003 confirms that the seismic Class II pathways are isolated. If the seismic Class II pathways are in use, the procedure directs operators to close a series of valves and secure certain pumps, thus isolating the seismic Class II pathways (July 28, 2015, supplement (ADAMS Accession No. ML15209A960)).

Minor changes to procedures are identified as a result of this LAR, but the existing operator manual actions remain largely unchanged from what is current practice at the plant.

The operator actions described above were assessed by an NRC risk analyst according to Section 2.4, "Screening Process for Non-Risk-Informed Change Requests," of NUREG-1764.

This assessment indicated that the risk profile associated with this change is very low due to the low frequency of seismic activity occurring concurrently with the BWST cleanup or recirculation operation. The amount of time that the plant can be in the BWST cleanup or recirculation alignment is further limited by the allowable timeframes indicated by this amendment. In

addition, this risk assessment examined the consequence of operators failing to isolate the seismic Class II piping post-earthquake when the ECCS injection source is needed (ADAMS Accession No. ML15236A181 ). The conclusion of this assessment is that the operator actions described in this LAR are of negligible risk-significance, and are, therefore, found to be appropriate for a Level Ill review (the lowest of the graded reviews possible under the guidance in NUREG-1764).

3.2.2.2 General Deterministic Review - Human Factors Criterion 2 of NUREG-1764 ensures that the licensee does not reduce DID. The July 23, 2015, LAR indicates that seismic evaluations of the Class II piping paths will withstand the postulated SSE. The use of the manual actions described above are DID measures, which provide additional assurance that connection of the BWST to Class II piping paths will not result in a leak by isolating this path shortly after a seismic event. Section 3.0 of the LAR indicates that the use of formalized administrative controls provides additional assurance that these manual actions will be given "very high priority" by control room staff. These actions are otherwise unchanged; therefore, operators are already trained on the actions necessary to complete these procedures.

This treatment essentially maintains (or improves) the existing level of DID through analysis.

Previously, the seismic Class II piping was assumed to fail during an SSE. Based on the licensee evaluation, the DID increases as a result of this analysis without changing the physical equipment and without major changes to administrative controls or manual actions. Therefore, the staff finds this treatment acceptable. However, the LAR does not provide sufficient evidence to support crediting the operator manual actions as the sole method for protecting the seismic Class II piping. As stated in TIA 2015-01, manual actions are not an acceptable method to meet the design basis without proper NRC analysis. The evaluation of manual actions described in this safety evaluation is applicable only as a DID measure and cannot be credited in lieu of the NRC confirmation that the seismic Class II piping can withstand an SSE. If the licensee chooses to credit the operator actions, additional information will be necessary to validate that operator manual actions can be performed as described. The conclusions drawn here are based upon the qualification of the seismic Class II components being able to withstand an SSE.

3.2.2.3 Additional Considerations - Human Factors Section 3.0 of the LAR also describes several human factors processes that were implemented or considered that are beyond what is necessary for a NUREG-1764, Level Ill, review. These considerations add additional assurance that the manual actions reviewed here can be completed. These include:

  • An operating experience review was conducted. It identified that two other plants used only administrative controls for isolation of the RWST with no negative effects identified.
  • There are no changes to the assignment of automatic/manual actions. Therefore, there is no need to perform a functional requirement analysis or function allocation.
  • There are no changes to staffing levels, operator qualifications, or training as a result of this change.
  • Marked up procedures are provided (July 23, 2015, LAR Attachment 9; and July 28, 2015, supplement, Attachments 2, 3, and 4). The changes to these procedures are minimal and are unlikely to cause negative effects on operators.

3.2.3 Conclusion - Human Factors The NRC staff completed a review of the operator manual actions proposed by this LAR. Based on the information provided in the LAR and supplement, the actions were found to be in accordance with NUREG-1764.

The manual actions reviewed here increase DID but have not been validated to be feasible or reliable under the circumstances that may be encountered during a seismically initiated line break. Therefore, acceptance of the proposed change is based upon the capability of the seismic Class II piping paths to withstand an SSE, and the operator manual actions being considered a DID measure only.

3.3 Reactor Systems Evaluation 3.3.1 Regulatory Evaluation - Reactor Systems The reactor systems regulatory evaluation identified the following acceptance criteria:

3.3.2 Technical Evaluation - Reactor Systems 3.3.2.1 Summary of Technical Information Provided by Licensee - Reactor Systems The licensee states in the application that a seismic evaluation was performed re-analyzing the seismic response of the cleanup system. The reanalysis determined that the cleanup and recirculation seismic Class II piping paths would maintain pressure boundary integrity during an SSE, which translates to the seismic Class I BWST maintaining its safety functions during an SSE while connected to the cleanup or recirculation paths.

3.3.2.2 NRC Evaluation - Reactor Systems GDC 35 requires that ECCS be able to provide emergency core cooling. As indicated in Section 3.1 of this Safety Evaluation (SE), with the BWST structural and pressure boundary integrity being maintained, the BWST, when connected to the cleanup and recirculation piping, will remain operable throughout an SSE, and the ECCS will maintain the capability to perform its

intended safety functions. Therefore, the design requirements of GDC 35 will not be impacted in this plant configuration.

3.3.2.3 NRC Conclusion - Reactor Systems The NRC staff determined that the structural and pressure boundary integrity of the BWST will be maintained during an SSE while connected to the cleanup and recirculation piping, which will allow ECCS to remain operable in the event of an SSE. Additionally, the NRC staff determined that the proposed changes to the existing operating procedures addressed in Section 3.2 of this SE provide DID in that the BWST can be isolated from the seismic Class II piping in the event of an SSE or OBE.

Based on the considerations discussed above, the NRC staff has determined that temporarily connecting the BWST to seismic Class II piping (i.e., the cleanup and recirculation piping) for a restricted amount of time is acceptable, and it does not compromise the ability of the plant to meet the requirements of GDC 35.

3.4 Technical Specifications Evaluation 3.4.1 Regulatory Evaluation - Technical Specifications The Commission's regulatory requirements related to the content of TSs are set forth in 10 CFR Section 50.36. This regulation requires that the TSs include items in five specific categories. These categories include (1) safety limits, limiting safety system settings, and limiting control settings; (2) LCOs; (3) surveillance requirements; (4) design features; and (5) administrative controls.

Additionally, 10 CFR 50.36(c)(2)(i), which the NRC staff evaluated the proposed TS amendment against, defines LCOs as the lowest functional capability or performance levels of equipment required for safe operation of the facility. When an LCO of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial action permitted by the TSs until the condition can be met.

3.4.2 Technical Evaluation - Technical Specifications The proposed TS amendment represents a relaxation from the TS 3.3.1.1 (a) requirements, which in their current form do not allow the BWST to connect to a seismic Class II system during the mode of applicability of the TS. The LAR proposed that two notes be added to TS 3.3.1.1 (a) to allow the BWST to be connected to seismic Class II piping (i.e., the cleanup and recirculation piping) for a limited time period and still meet the LCO requirements (i.e., the BWST remains operable when the reactor is critical). The limited times stipulated in Note 1 and Note 2 are reasonable to perform the BWST cleanup and surveillance testing.

In order to justify relaxing the requirements of TS 3.3.1.1 (a), the licensee performed a seismic evaluation, which demonstrated the ability of the existing cleanup and recirculation paths to maintain structural and pressure boundary integrity during an SSE. This seismic evaluation was deemed acceptable by the NRC staff, and it provides reasonable assurance that leakage will

not occur during BWST cleanup or recirculation operations in the event the site experiences an SSE.

As an additional measure, the licensee is implementing administrative controls via operating procedures that will remove the BWST from cleanup or recirculation operations if a seismic event should occur. The procedures require operators to manually isolate (i.e., double isolate) the BWST from the seismic Class II piping and equipment. These manual actions are considered DID measures, and they are not the basis for justifying the relaxation of TS 3.3.1.1 (a) requirements.

Also, the licensee submitted a proposed TS Bases page with the LAR that describes the proposed notes for TS 3.3.1.1 (a).

3.4.3 Conclusion - Technical Specifications The NRC staff determined that the licensee provided sufficient justification for the proposed TS amendment. As part of the LAR, the licensee submitted a seismic stress analysis that demonstrates the capability of the BWST to withstand an SSE when connected to seismic Class II piping during cleanup and recirculation operations. This analysis indicates that the BWST will meet its LCO requirements by retaining the ability to perform its intended safety functions in the event of an SSE while connected to the seismic Class II piping in question. Also, the proposed TS amendment limited the amount of time the licensee is permitted to connect the BWST to the cleanup and recirculation piping. Based on the seismic evaluation and time restrictions, the NRC staff determined that (1) the requirements of 10 CFR Section 50.36(c)(2)(i) are being met, and (2) the change is acceptable.

4.0 FINAL NO SIGNIFICANT HAZARDS CONSIDERATION

DETERMINATION The NRC's regulations in 10 CFR 50.92 state that the NRC may make a final determination that a license amendment involves no significant hazards consideration if operation of the facility, in accordance with the amendment, would not: (1) involve a significant increase in the probability or consequences of an accident previously evaluated; or (2) create the possibility of a new or different kind of accident from any accident previously evaluated; or (3) involve a significant reduction in a margin of safety.

As required by 10 CFR 50.91 (a), the licensee, in its letter dated July 28, 2015, provided its analysis of the issue of no significant hazards consideration, using the standards in 10 CFR 50.92. The licensee's evaluation is provided below.

First Standard Does the proposed amendment involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No.

The use of the Liquid Waste Disposal System (WDL) and the Spent Fuel Pool Cooling System (SF) to re-circulate and cleanup the BWST contents does not involve any physical changes or

modifications to the plant, or create any new interfaces with the reactor coolant system.

Therefore, the connection of the WDL and SF to the BWST would not affect the probability of Large and Small Break Loss of Coolant Accidents occurring. The WDL and the applicable components of the SF are not credited for safe shutdown of the plant or accident mitigation. A technical evaluation was performed to validate the seismic adequacy of the WDL piping to withstand a Safe Shutdown Earthquake (SSE). The evaluation determined sufficient margin exists in the installed piping and supports such that during an SSE, the WDL system and piping would not lose pressure boundary integrity. In addition, as additional defense-in-depth measure, administrative controls ensure that the BWST can be isolated from seismic Class II WDL piping following an SSE. Since the BWST will continue to perform its safety functions and overall system performance is not affected, the consequences of an accident are not increased.

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

Second Standard Does the proposed amendment create the possibility of a new or different kind of accident from any accident previously evaluated?

Response: No.

The design of the BWST, WDL and SF systems to allow recirculation and filtration I demineralization has not been altered. No new procedures are required to start or end BWST Cleanup or Recirculation operation. Proposed changes to the existing operating procedures will provide a higher priority and quicker response to isolate the BWST from seismic Class II piping paths, if operating in Cleanup or Recirculation modes, as an additional defense-in-depth administrative control during a seismic event. Since the seismic adequacy of the interconnected WDL system and piping has been evaluated for an SSE and validated by calculations to maintain pressure boundary integrity, the BWST safety functions are not affected.

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

Third Standard Does the proposed amendment involve a significant reduction in a margin of safety?

Response: No.

The WDL and applicable components of the SF are not credited for safe shutdown of the plant or accident mitigation. The seismic adequacy of the BWST is maintained. The seismic evaluation determined that sufficient margin exists in the installed piping and supports such that during an SSE, the seismic Class II WDL system and piping would not lose pressure boundary integrity. Maximum piping and piping support stresses are below their respective allowables, are acceptable, and no pipe leakage will occur.

Therefore, the proposed changes do not involve a significant reduction in a margin of safety.

The Commission previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (80 FR 47529; August 7, 2015). The NRC staff has reviewed the licensee's no significant hazards consideration analysis. Based on this review and on the NRC staff's SE of the underlying LAR, the NRC staff concludes that the three standards of 10 CFR 50.92(c) are satisfied. Therefore, the NRC staff has made a final determination that no significant hazards consideration is involved for the proposed amendment and that the amendment should be issued as allowed by the criteria contained in 10 CFR 50.91.

5.0 STATE CONSULTATION

In accordance with the Commission's regulations, the Pennsylvania State official was notified of the proposed issuance of the amendment. The State official had no comments.

6.0 ENVIRONMENTAL CONSIDERATION

The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has also determined that the amendment involves no significant hazards consideration. Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.

6.0 CONCLUSION

The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) there is reasonable assurance that such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

Principal Contributors: B. Green M. Hardgrove K. Hsu W. Satterfield R. Gladney Date: October 1, 2015

October 1, 2015 Mr. Bryan C. Hanson President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555

SUBJECT:

THREE MILE ISLAND NUCLEAR STATION, UNIT 1 - ISSUANCE OF AMENDMENT FOR TEMPORARY RESTORATION OF THE BORATED WATER STORAGE TANK CLEANUP AND RECIRCULATION OPERATION (TAC NO. 6504)

Dear Mr. Hanson:

The Commission has issued the enclosed Amendment No. 289 to Renewed Facility Operating License No. DPR-50 for Three Mile Island Nuclear Station, Unit 1 (TMI), in response to your application dated July 23, 2015, as supplemented by letters dated July 28, 2015, and August 25, 2015.

The amendment revises TMI Technical Specification 3.3.1.1, "Injection Systems," to allow for the temporary operation of the borated water storage tank under administrative and design controls while connected to seismic Class II piping. This change would support necessary cleanup and surveillance activities associated with the TMI Fall 2015 Refueling Outage and Fuel Cycle 21 operation.

A copy of the related safety evaluation is also enclosed. Notice of Issuance will be included in the Commission's Biweekly Federal Register Notice.

Sincerely, IRA/

Robert L. Gladney, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-289

Enclosures:

1. Amendment No. 289 to Renewed DPR-50
2. Safety Evaluation cc w/enclosures: Distribution via Listserv DISTRIBUTION:

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NAME LRonewicz RElliott TLupold CJackson GCasto RGladney (RPettis for) (EDavidson for)

DATE 9/29/15 9/10/15 9/14/15 9/11/15 9/14/15 9/14/15 OFFICE APHB/BC

  • OGC OGC LPL 1-2/BC LPL 1-2/PM NAME SWeerakody DRoth Jlindell RGladney (Final DBroaddus NHSC)

DATE 9/11/15 9/25/15 9/30/15 10/1/15 10/1/15