ML20066E040

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Supplemental Information Associated with the License Amendment Request to Add a One-Time Note for Use of Alternate Residual Heat Removal Methods
ML20066E040
Person / Time
Site: Ginna Constellation icon.png
Issue date: 03/05/2020
From: Rafferty-Czincila S
Exelon Generation Co
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML20066E040 (16)
v • d • e


Text

Exelon Generation ~

200 Exelon Way Kennett Square. PA 19348 www.exeloncorp.com 10 CFR 50.90 March 5, 2020 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 R. E. Ginna Nuclear Power Plant Renewed Facility Operating License No. DPR-18 NRC Docket No. 50-244

Subject:

Supplemental Information Associated with the License Amendment Request to Add a One-Time Note for Use of Alternate Residual Heat Removal Methods Reference 1. Letter from S. Rafferty-Czincila (Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, "License Amendment Request to Add a One-Time Note for Use of Alternate Residual Heat Removal Methods," dated February 25, 2020 In the Reference 1 letter, Exelon Generation Company, LLC (EGC) requested changes to the Technical Specifications (TS) of the R. E. Ginna Nuclear Power Plant (Ginna). EGC proposed to revise TS 3.4. 7 ("RCS Loops - MODE 5, Loops Filled"), TS 3.4.8 ("RCS Loops

- MODE 5, Loops Not Filled"), TS 3.9.4 ("Residual Heat Removal (RHR) and Coolant Circulation - Water Level <:!: 23 Ft"), and TS 3.9.5 ("Residual Heat Removal (RHR) and Coolant Circulation - Water Level < 23 Ft") to add an asterisk to allow the use of alternate means for residual heat removal. Detailed descriptions of the alternatives were provided in the Technical Evaluation. This one-time change was requested to support the station in the shutdown of the reactor during the upcoming refueling outage scheduled to start in April 2020.

In a March 2, 2020 public meeting with the U.S. Nuclear Regulatory Commission (Attachment 1 contains the EGC meeting participants), EGC was requested to supplement the Reference 1 submittal with additional information. Attachment 2 contains our response to this request. Attachment 3 contains revised Technical Specification pages.

EGC has reviewed the information supporting a finding of no significant hazards consideration, and the environmental consideration, that were previously provided to the NRC in the Reference 1 letter. The supplemental information provided in this response does not affect the bases for concluding that the proposed license amendment does not involve a significant hazards consideration under the standards set forth in 10 CFR 50.92. In addition, EGC has concluded that the information provided in this supplemental response does not affect the bases for concluding that neither an environmental impact statement nor an environmental assessment needs to be prepared in connection with the proposed amendment.

Supplemental Information Associated with the License Amendment Request to Add a One-Time Note for Use of Alternate Residual Heat Removal Methods March 5, 2020 Page 2 There are no regulatory commitments contained in this submittal. Should you have any questions concerning this submittal, please contact Tom Loomis at (610) 765-5510.

I declare under penalty of perjury that the foregoing is true and correct. This statement was executed on the Slh day of March 2020.

Respectfully, Attachments: 1. List of Public Meeting Attendees

2. Supplemental Information
3. Revised Markup of Proposed Technical Specifications Pages cc: NRC Regional Administrator, Region I NRC Senior Resident Inspector, Ginna NRC Project Manager, Ginna A. L. Peterson, NYSERDA

Attachment 1 List of Public Meeting Attendees Page 1 Attachment 1 List of Public Meeting Attendees Exelon Generation Company, LLC Participants Paul Swift, Site Vice President Daren Blankenship, Plant Manager Mark Geckle, Director, Organizational Performance and Regulatory Assurance Jarred Jackson, Ginna Senior Manager Engineering Justin Knowles, Senior Manager Operations Support & Services Damon Peters, Senior Staff Engineer James Breunig, Manager Engineering George Wrobel, Regulatory Assurance Manager Tom Loomis, Principle Regulatory Engineer Jessie Hodge, Senior Regulatory Engineer Antoinette Walter, Senior Regulatory Engineer

Attachment 2 Supplemental Information

Supplemental Information Page 1 Question:

"1. Consider realigning the

  • and note to ensure changes in upward Modes are not allowed."

"2. Consider adding the word 'approved' in the

  • note before the term 'alternate means of RHR'."

Response

A revised markup of Technical Specification pages which includes these changes is provided in .

Question:

"3. Provide performance details for the alternate RHR flow."

Response

The following is supplemental information for Section "3.0 Technical Evaluation," which provides performance details for the alternate RHR flow.

The modification that would be installed to facilitate the Alternate RHR Cooling #1 (Figure 2 in the License Amendment Request dated February 25, 2020) includes the use of stainless steel hose between the tees that would be installed between 721 and 720, and between 700 and 701. This hose run is approximately 150 feet and is longer than the run that would be required to implement Alternate RHR Cooling #2 (Figure 3 of the License Amendment Request). By increasing the suction length and using stainless steel hose, the suction losses would be greater than the existing system. An evaluation was completed to demonstrate that adequate flow would still be achieved.

The limiting condition for RHR flow would be during Reactor Coolant System drain down following installation of the modification and cooldown. In this condition, the Reactor Coolant System is vented, and the Reactor Coolant Pump is shut off. The drain down is to reactor vessel flange level to facilitate the reactor head removal in preparation for refueling. At this level in the Reactor Coolant System, the RHR pump flow is limited by Net Positive Suction Head (NPSH) to ~2125 gpm. With both RHR and Component Cooling Water (CCW) heat exchangers aligned, the heat removal capability at a Reactor Coolant System temperature of 140°F has been calculated to be 45 MBTU/hr with the expected lake temperature conditions of ~45°F. This corresponds to a decay heat less than 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> post-shutdown (see decay heat table below). Since the modification would take several days to install, the decay heat would be reduced to a much lower value by the time the modification is installed.

Prior to shutting the Reactor Coolant Pump off, the Reactor Coolant System is pressurized above 220 psig to maintain the required Reactor Coolant Pump seal differential pressure. There is no concern with NPSH available to the RHR pumps with Reactor Coolant System pressure elevated above 220 psig. Previous evaluations performed for Ginnas extended power uprate (EPU) in 2006 used a minimum flow of 1500 gpm per pump under these conditions with a Reactor Coolant Pump running. This was determined to be more than enough for cooldown. The pumps would remain capable of exceeding 1500 gpm each when run in parallel with the RCS pressurized.

Supplemental Information Page 2 Decay Heat Table Time Decay after Heat Rate Shutdown (MBTU/hr)

(hours) 12 39.7 15 37.4 20 34.7 25 32.7 30 31.1 35 29.9 40 28.9 45 28.0 50 27.2 60 25.9 70 24.9 80 24.0 90 23.3 100 22.7 120 21.6 Question:

"4. Add a figure into the License Amendment Request Technical Evaluation for the solid Steam Generator cooldown flowpath, as well as a table comparing Reactor Coolant Pump and decay heat loads with the capacity of the condensate cooling method."

Response

The following is supplemental information for the Section "3.0 Technical Evaluation."

Figure 1 shows the water-solid Steam Generator cooldown flow path. The decay heat loads are shown above in the response to Question 3, and the heat addition due to a Reactor Coolant Pump running is 17.1 MBTU/hr. The condensate cooler was determined to be capable of removing 53.9 MBTU/hr at peak summer conditions (conservative for this evaluation due to higher assumed cooling water temperature) with the Reactor Coolant System at 300°F; therefore, the heat removal with a Reactor Coolant Pump running will match decay heat at approximately 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> post-shutdown.

This is the expected time that water-solid Steam Generator cooldown would be initiated.

Supplemental Information Page 3 Water Solid Steam Generator Cooldown Flowpath

Attachment 3 Revised Markup of Proposed Technical Specifications Pages TECHNICAL SPECIFICATIONS PAGES 3.4.7-1 3.4.7-2 (information only) 3.4.8-1 3.4.8-2 (information only) 3.9.4-1 3.9.4-2 (information only) 3.9.5-1 3.9.5-2 (information only)

RCS Loops - MODE 5, Loops Filled 3.4.7 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.7 RCS Loops - MODE 5, Loops Filled LCO 3.4.7 One residual heat removal (AHR) loop shall be OPERABLE and In operation, and either~ -----fl

a. Ona additional AHR loop shall be OPERABL~ -
b. The secondary side water level of at least one steam generator (SG) shall be~ 16%.

-NOTE-

1. The AHR pump of the loop in operation may be de-energized for

~ 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> per 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> period provided:

a. No operations are permitted that would cause introduction of coolant Into the ACS with boron concentration less than required to meet the SDM of LCO 3.1.1; and
b. Core outlet temperature is maintained at least 10°F below saturation temperature.
2. One required AHR loop may be inoperable for s; 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for surveillance testing provided that the other AHR loop is OPERABLE and in operation.
3. No reactor coolant pump shall be started with one or more ACS cold leg temperatures less than or equal to the LTOP enable temperature specified in the PTLA unless:
a. The secondary side water temperature of each SG Is s; 50°F above each of the RCS cold leg temperatures; or
b. The pressurizer water volume is< 324 cubic feet (38% level).
4. All AHR loops may be removed from operation during planned heatup to MODE 4 when at least one RCS loop is in operation.

APPLICABILITY: MODE 5 with RCS loops filled.

-

  • Beginning April 1, 2020, an alternate approved means of RHR may be provided until June 30, 2020.

No increase in Mode changes will be permitted while utilizing the alternate approved means of RHR.

R.E. Ginna Nuclear Power Plant 3.4.7-1 Amendment 118

RCS Loops - MODE 5, Loops Filled 3.4.7 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. OneRHRloop A.1 Initiate action to restore a Immediately inoperable. second RHR loop to OPERABLE status.

ANO OR Both SGs secondary side water levels not within A.2 Initiate action to restore Immediately limits. required SG secondary side water levels to within limits.

B. Both RHR loops B.1 Suspend operations that Immediately inoperable. would cause introduction of coolant into the RCS with OR boron concentration less than required to meet the No RHR loop In SOM of LCO 3.1.1.

operation.

AND 8.2 Initiate action to restore one Immediately RHR loop to OPERABLE status and operation.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR3.4.7.1 Verify one RHR loop is in operation. In accordance with lthe Surveillance Frequency Control Program SR3.4.7.2 Verify SG secondary side water level is ~ 16% in the In accordance with required SG. he Surveillance Frequency Control Program SR3.4.7.3 Verify correct breaker alignment and indicated power In accordance with are available to the required RHR pump that is not in ~he Surveillance Frequency Control operation.

Program SR 3.4.7.4 Verify required RHR loop locations susceptible to gas In accordance with accumulation are sufficiently filled with water. the Surveillance Frequency Control Program R.E. Ginna Nuclear Power Plant 3.4.7-2 Amendment No. 122

ACS Loops

-NOTE-

1. All AHR pumps may be de-energized for ~ 15 minutes when switching from one loop to another provided:
a. No operations are permitted that would cause introduction of coolant into the RCS with boron concentration less than required to meet the SOM of LCO 3.1.1; and
b. Core outlet temperature is maintained at least 10°F below saturation temperature; and
c. No draining operations to further reduce the RCS water volume are permitted.
2. One AHR loop may be Inoperable for 5i 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for surveillance testing provided that the other AHR loop is OPERABLE and in operation.

APPLICABILITY: MODE 5 with RCS loops not filled.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. One AHR loop A.1 Initiate action to restore Immediately inoperable. AHR loop to OPERABLE status.

B. Both AHR loops B.1 Suspend operations that Immediately inoperable. would cause introduction of coolant into the RCS with OR boron concentration less than required to meet the No AHR loop in SOM of LC03.1.1.

operation.

AND

  • Beginning April 1, 2020, an alternate approved means of RHR may be provided until June 30, 2020.

No increase in Mode changes will be permitted while utilizing the alternate approved means of RHR.

R.E. Ginna Nuclear Power Plant Amendment 11 B

RCS Loops - MODE 5, Loops Not Filled 3.4.8 CONDITION REQUIRED ACTION COMPLETION TIME 8.2 Initiate action to restore one Immediately RHR loop to OPERABLE status and operation.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY

~n accordance with SR3.4.8.1 Verify one RHR loop is in operation.

he Surveillance Frequency Control Program Verify correct breaker alignment and indicated power In accordance with SR3.4.8.2 he Surveillance are available to the RHR pump that is not in Frequency Control operation.

Program Verify RHR loop locations susceptible to gas In accordance with SR 3.4.8.3 he Surveillance accumulation are sufficiently filled with water.

Frequency Control Program R.E. Ginna Nuclear Power Plant 3.4.8-2 Amendment No. 122

AHA and Coolant Circulation - Water Level<: 23 Ft 3.9.4 n 3.9 REFUELING OPERATIONS 3.9.4 Residual Heat Removal (AHR) and Coolant Circulation - Water Level ~ 23 Ft LCO 3.9.4 One AHR loop shall be OPERABLE and in operation.~

-NOTE-The required AHR loop may be removed from operation for :5 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> per 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> period, provided no operations are permitted that would cause introduction of coolant into the Reactor Coolant System (RCS) with boron concentration less than that required to meet the minimum required boron concentration of LCO 3.9.1.

APPLICABILITY: MODE 6 with the water level <:: 23 ft above the top of reactor vessel flange.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. AHR loop requirements A.1 Suspend operations that Immediately not met. would cause introduction of coolant into the RCS with boron concentration less than required to meet the boron concentration of LCO 3.9.1.

A.2 Suspend loading irradiated Immediately fuel assemblies in the core.

A.3 Initiate action to satisfy AHR Immediately loop requirements.

  • Beginning April 1, 2020, an alternate approved means of RHR may be provided until June 30, 2020.

No increase in Mode changes will be permitted while utilizing the alternate approved means of RHR.

R.E. Ginna Nuclear Power Plant 3.9.4-1 Amendment 118

RHR and Coolant Circulation - Water Level ;::: 23 Ft 3.9.4 CONDITION REQUIRED ACTION COMPLETION TIME

':)

A.4 Close all containment 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> penetrations providing direct access from containment atmosphere to outside atmosphere.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR3.9.4.1 Verify one RHR loop is in operation and circulating In accordance with

~he Surveillance reactor coolant.

Frequency Control Program SR 3.9.4.2 Verify required RHR loop locations susceptible to In accordance with gas accumulation are sufficiently filled with water. the Surveillance Frequency Control Program

')

R.E. Ginna Nuclear Power Plant 3.9.4-2 Amendment No.122

RHR and Coolant Circulation* Water Level< 23 Ft 3.9.5 3.9 REFUELING OPERATIONS 3.9.5 Residual Heat Removal (RHR) and Coolant Circulation - Water Level < 23 Ft LCO 3.9.5 Two RHA loops shall be OPERABLE, and one AHR loop shall be in operation.~

APPLICABILITY: MODE 6 with the water level < 23 ft above the top of reactor vessel flange.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. Less than the required A.1 Initiate action to restore Immediately number of AHR loops RHR loop(s) to OPERABLE OPERABLE. status.

OR A.2 Initiate action to establish Immediately

~ 23 ft of water above the top of reactor vessel flange.

B. No AHR loop in B.1 Suspend operations that Immediately operation. would cause introduction of coolant into the RCS with boron concentration less than required to meet the boron concentration of LCO 3.9.1.

AND B.2 Initiate action to restore one Immediately RHA loop to operation.

AND B.3 Close all containment 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> penetrations providing direct access from containment to outside atmosphere.

  • Beginning April 1, 2020, an alternate approved means of RHR may be provided until June 30, 2020.

No increase in Mode changes will be permitted while utilizing the alternate approved means of RHR.

R.E. Ginna Nuclear Power Plant 3.9.5*1 Amendment 118

RHR and Coolant Circulation - Water Level < 23 Ft 3.9.5 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR3.9.5.1 Verify one RHR loop is in operation and circulating In accordance with reactor coolant. the Surveillance Frequency Control Program In accordance with SR3.9.5.2 Verify correct breaker alignment and indicated power

~he Surveillance available to the required RHR pump that is not in Frequency Control operation.

Program In accordance with SR 3.9.5.3 Verify RHR loop locations susceptible to gas

~he Surveillance accumulation are sufficiently filled with water.

Frequency Control Program

()

R.E. Ginna Nuclear Power Plant 3.9.5-2 Amendment No. 122

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