L-2022-143, Subsequent License Renewal Application - Aging Management Requests for Additional Information Set 1A Response

Subsequent License Renewal Application - Aging Management Requests for Additional Information Set 1A Response

ML22251A202
Person / Time
Site:	Saint Lucie
Issue date:	09/08/2022
From:	Maher W Florida Power & Light Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
L-2022-143
Download: ML22251A202 (45)

Text

September 08, 2022

L-2022-143 10 CFR 54.17

U.S. Nuclear Regulatory Commission Attn: Document Control Desk 11545 Rockville Pike One White Flint North Rockville, MD 20852-2746

St. Lucie Nuclear Plant Units 1 and 2 Dockets 50-335 and 50-389 Renewed Facility Operating Licenses DPR-67 and NPF-16

SUBSEQUENT LICENSE RENEWAL APPLICATION - AGING MANAGEMENT REQUESTS FOR ADDITIONAL INFORMATION (RAI) SET 1A RESPONSE

References:

1. FPL Letter L-2021-192 dated October 12, 2021 - Subsequent License Renewal Application -

Revision 1 (ADAMS Accession No. ML21285A107) 2. FPL Letter L-2022-043 dated April 7, 2022 - Subsequent License Renewal Application Revision 1 - Supplement 1 (ADAMS Accession No. ML22097A202) 3. FPL Letter L-2022-044 dated April 13, 2022 - Subsequent License Renewal Application Revision 1 - Supplement 2 (ADAMS Accession No. ML22103A014) 4. FPL Letter L-2022-071 dated May 19, 2022 - Subsequent License Renewal Application Revision 1 - Supplement 3 (ADAMS Accession No. ML22139A083) 5. NRC Email and Attachment dated July 11, 2022, St. Lucie SLRA RAI Safety Set 3 Final (ADAMS Accession Nos. ML22193A086, ML22193A087) 6. FPL Letter L-2022-108 dated July 11, 2022 - Subsequent License Renewal Application -

Aging Management Requests for Additional Information (RAI) Set 2 Response 7. NRC Email and Attachment dated August 4, 2022, St. Lucie SLRA RAI (Second Round) 1a

Florida Power & Light Company (FPL), owner and licensee for St. Lucie Nuclear Plant (PSL) Units 1 and 2, has submitted a revised and supplemented subsequent license renewal application (SLRA) for the Facility Operating Licenses for PSL Units 1 and 2 (References 1-4). Based on the NRCs review of the SLRA, the NRC issued its Set 1a RAIs to FPL (Reference 7). Attachments 1-6 to this letter provide the response to those information requests. In addition, Attachment 6 to this letter provides a response to RAI B.2.3.27-1a that supersedes the previous Set 1a, Attachment 14 response (Reference 6). Attachment 7 to this letter supersedes the previously submitted SLRA Revision 1, Supplement 1, Attachment 18 submittal (Reference 2).

Florida Power & Light Company

 

15430 Endeavor Drive, Jupiter, FL 33478 St. Lucie Nuclear Plant Units 1 and 2 Dockets 50-335 and 50-389 L-2022-143 l Page 2 of 3

Certain attachments include associated revisions to the SLRA (Enclosure 3 Attachment 1 of Reference 1, as supplemented by References 2 - 4) denoted by strikethrough (deletion) and/or bold red underline (insertion) text. Previous SLRA revisions are denoted by bold black text. SLRA table revisions are included as excerpts from each affected table.

Should you have any questions regarding this submittal, please contact me at (561) 304-6256 or William.Maher@fpl.com.

I declare under penalty of perjury that the foregoing is true and correct.

Executed on the 8th day of September 2022.

Sincerely, Digitally signed by William Maher William DN: cn=William Maher, o=Nuclear, ou=Nuclear Licensing Projects, email=william.maher@fpl.com, Maher c=US Date: 2022.09.08 10:30:22 -04'00' William D. Maher Licensing Director - Nuclear Licensing Projects Florida Power & Light Company

Attachment:

PSL Response to NRC RAI No. B.2.3.27-1a

Cc: Regional Administrator, USNRC, Region II Senior Resident Inspector, USNRC, St. Lucie Plant Chief, USNRC, Division of New and Renewed Licenses Senior Project Manager, USNRC, Division of New and Renewed Licenses Chief, Bureau of Radiation Control, Florida Department of Health











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St. Lucie Units 1 and 2 Dockets 50-335 and 50-389 PSL Response to NRC RAI No. B.2.3.27-1a L-2022-143 Attachment 1 Page 1 of 42

Buried and Underground Piping and Tanks AMP

RAI B.2.3.27-1a

Regulatory Basis

Section 54.21(a)(3) of Title 10 of the Code of Federal Regulations (10 CFR) requires an applicant to demonstrate that the effects of aging for structures and components will be adequately managed so that the intended function(s) will be maintained consistent with the current licensing basis for the period of extended operation. One of the findings that the U.S.

Nuclear Regulatory Commission (NRC) staff must make to issue a renewed license (10 CFR 54.29(a)) is that actions have been identified and have been or will be taken with respect to managing the effects of aging during the period of extended operation on the functionality of structures and components that have been identified to require review under 10 CFR 54.21, such that there is reasonable assurance that the activities authorized by the renewed license will continue to be conducted in accordance with the current licensing basis. In order to complete its review and enable making a finding under 10 CFR 54.29(a), the staff requires additional information in regard to the matters described below.

=

Background===

SLRA Section B.2.3.27, Buried and Underground Piping and Tanks, states [t]he number of inspections for each 10-year inspection period, commencing 10 years prior to the start of SPEO, are based on the inspection quantities noted in NUREG-2191, Table XI.M41-2, adjusted for a 2-Unit plant site.

GALL-SLR Report Table XI.M41-1, Preventive Actions for Buried and Underground Piping and Tanks, recommends that buried stainless steel piping is externally coated in accordance with the preventive actions program element of GALL-SLR Report AMP XI.M41, Buried and Underground Piping and Tanks.

In addition, GALL-SLR Report AMP XI.M41 states the following:

x [a]dditional inspections, beyond those in Table XI.M41-2, Inspection of Buried and Underground Piping and Tanks, may be appropriate if exceptions are taken to program element 2, preventive actions, or in response to plant-specific operating experience.

x [t]here are no recommended preventive actions [e.g., external coatings] for titanium alloy, super austenitic stainless steels, and nickel alloy materials.

By letter dated June 13, 2022 (ADAMS Accession No. ML22164A802), the applicant stated the following in response to RAIs B.2.3.27-1 and B.2.3.21-2 (respectively):

x [a] portion of the Unit 1 auxiliary feedwater (AFW) and condensate system (AFW pump suction) is buried stainless steel piping in sand beneath the turbine building. No coating was identified, however, due to the location beneath the turbine building, this buried piping is not susceptible to wetting.

St. Lucie Units 1 and 2 Dockets 50-335 and 50-389 PSL Response to NRC RAI No. B.2.3.27-1a L-2022-143 Attachment 1 Page 2 of 42

x [t]he table [referring to the soil corrosivity sampling results table] does not include an outlier soil sample associated with a Unit 2 intake cooling water (ICW) line, since that sample had been impacted by local saltwater foaming from the ICW discharge overflow/standpipe. The caulking between the standpipe and the concrete decking was weathered and porous, allowing saltwater foam to permeate into the soil.

In response to RAI B.2.3.21-2, the applicant provided results from seven soil corrosivity samples which included the following parameters: pH, soil resistivity, moisture, chlorides, sulfates, redox potential, and microbiology. Based on its review of this data, the staff noted that the soil can be considered appreciably corrosive (using average values) or severely corrosive (using least conservative values) to stainless steel when scoring in accordance with Table 9-4, Soil Corrosivity Index from BPWORKS, of Electric Power Research Institute (EPRI) Report 3002005294, Soil Sampling and Testing Methods to Evaluate the Corrosivity of the Environment for Buried Piping and Tanks at Nuclear Power Plants.

Issue

The basis provided by the applicant for having uncoated buried stainless steel (i.e., an exception to GALL-SLR AMP XI.M41 guidance) is that the piping is not exposed to significant amounts of moisture (i.e., wetting). However, the staff notes that soil parameters beyond moisture (i.e., pH, soil resistivity, chlorides, sulfates, redox potential, and microbiology) impact the susceptibility of buried stainless steel to external corrosion. Based on the soil corrosivity data provided in the response to RAI B.2.3.21-2, the environment at St. Lucie can be considered corrosive to buried stainless steel. In addition, based on its review of the response to RAI B.2.3.21-2, the staff notes that there has been at least one incident of saltwater intrusion into the soil. Based on its review of Table 9-4 of EPRI Report 3002005294, the staff also notes buried stainless is more sensitive to the effects of chlorides than any other material type.

Request

1. State the approximate length of uncoated in-scope buried stainless steel piping.

2. State the basis for why the inspection quantities in GALL-SLR Report Table XI.M41-2 are appropriate for buried stainless steel piping. The technical basis could include (but is not limited to) discussion of the following: results of soil corrosivity testing in the vicinity of the subject piping, results of inspections of buried uncoated stainless steel piping, and type(s) of in-scope stainless steel (e.g., super austenitic) piping utilized in uncoated buried applications, etc.

References.

x EPRI. EPRI 3002005294, Soil Sampling and Testing Methods to Evaluate the Corrosivity of the Environment for Buried Piping and Tanks at Nuclear Power Plants.

Palo Alto, California: Electric Power Research Institute. Novem ber 6, 2015.

St. Lucie Units 1 and 2 Dockets 50-335 and 50-389 PSL Response to NRC RAI No. B.2.3.27-1a L-2022-143 Attachment 1 Page 3 of 42

PSL Response:

The only buried stainless steel piping at St. Lucie, which could not be confirmed as coated or encased in concrete, is comprised of the Unit 1 auxiliary feedwater (AFW) pump recirculation piping and condensate system (AFW pump suction) piping. Therefore, this piping is conservatively assumed to be uncoated. This grade 316 stainless steel piping traverses beneath the Unit 1 turbine building and has a total length of approximately 520 ft.

At St. Lucie, the application of external coatings on safety-related piping is a design feature and is controlled by engineering specifications and design drawings, as appropriate. The St. Lucie Unit 1 design specifications and drawings for buried stainless steel piping do not specify the application of a coating material.

NUREG-2191, Table XI.M41-1 identifies coatings and backfill as preventative actions for buried stainless steel piping. The Unit 1 buried grade 316 stainless steel piping meets the backfill preventive action in Table XI.M41-1. The soil environment in contact with this buried stainless steel piping is composed of backfill in accordance with the applicable plant specification, which is available on the ePortal and summarized as follows:

x Material to be used as compacted backfill for Unit 1 shall be a selected sand and be free of muddy material, organic matter, rubbish, debris, or other unsuitable materials. The moisture content of the sand shall be within the limits required to obtain the specified compaction. Dredged material shall be stockpiled so as to facilitate drainage. No limerock shall be used for fill. This meets and exceeds the NACE SP0169-2007 (Reference 1), Section 5.2.3.4 backfill recommendation from NUREG-2191.

x Backfill material designated as Class I material for Unit 1 shall have no more than 12%

silt content (finer than No. 200 sieve), be free of clay balls, and no rock fragments larger than 6 inches shall be used for the fill except in areas where hand compaction is required wherein the maximum rock fragment size shall not exceed 3 inches. Sieve analyses are performed in accordance with ASTM D422 or D1140. Only Class I backfill is used at St. Lucie. This meets and exceeds the ASTM D 448-08 (Reference 2) size recommendation from NUREG-2191.

Although stainless steel is susceptible to attack by chlorides, such attacks are primarily catalyzed when moisture breaks the chloride molecules ionic bonds freeing chlorine ions to attack the stainless steel piping. The concrete floor slab associated with the turbine building shields the piping from rainwater, saltwater, and other moisture or chloride intrusion. Even if moisture intrusion occurred, sand is known to have relatively good drainage properties, so stagnant moisture leading to a continued chloride attack would not occur. Additionally, as identified in the response to Set 1 RAI B.2.3.21-2, the majority of the soil samples listed had chloride and sulfate readings below the threshold of detection. The two exceptions to this were at soil samples near the intake cooling water (ICW) piping on the intake side of the plant, which measured 205 mg/kg dry chlorides and 149 mg/kg dry sulfates, and the outlier sample near the discharge structure where saltwater intrusion had occurred (Reference 3). Neither of the two outlier sample locations are near any of the subject grade 316 stainless steel piping.

St. Lucie Units 1 and 2 Dockets 50-335 and 50-389 PSL Response to NRC RAI No. B.2.3.27-1a L-2022-143 Attachment 1 Page 4 of 42

An operating experience (OE) search of the 10-year action request (AR) database and component database (NAMS) did not identify any aging-related degradation for the Unit 1 stainless steel AFW and condensate system piping buried beneath the Unit 1 turbine building nor was age-related degradation identified for any other buried stainless steel piping at the site.

Due to the low number of chlorides within the soil, the low likelihood of stagnant moisture due to the concrete floor slab shielding, good soil/backfill drainage, and no history of negative OE, an exception to the NUREG-2191 recommendation of coating buried stainless steel piping as a preventive action is reasonable and will be taken with respect to the Unit 1 stainless steel AFW pump recirculation piping and condensate system (AFW pump suction) piping buried beneath the Unit 1 turbine building. Additionally, for the same reasoning, the inspection quantities listed in NUREG-2191 Table XI.M41-2 are adequate for providing reasonable assurance that the uncoated buried stainless piping at St. Lucie will maintain its pressure boundary function throughout the SPEO.

Due to the new exception for buried stainless steel piping coatings, the following SLRA tables and sections are impacted:

x Table 3.3-1, Summary of Aging Management Evaluations for the Auxiliary Systems x Table 3.3.2-4, Diesel Generators and Support Systems - Summary of Aging Management Evaluation x Table 3.3.2-5, Fire Protection / Service Water - Summary of Aging Management Evaluation x Table 3.3.2-8, Intake Cooling Water / Emergency Cooling Canal - Summary of Aging Management Evaluation x Table 3.3.2-9, Primary Makeup Water - Summary of Aging Management Evaluation x Table 3.3.2-12, Ventilation - Summary of Aging Management Evaluation x Table 3.4-1, Summary of Aging Management Evaluations for the Steam and Power Conversion Systems

x Table 3.4.2-3, Auxiliary Feedwater and Condensate - Summary of Aging Management Evaluation

x Table B-4, PSL Aging Management Program Consistency with NUREG-2191

x Section B.1.1, Overview

x Section B.2.3.27, Buried and Underground Piping and Tanks

Several of the impacted pages associated with the above tables and sections were also impacted by previous SLRA Supplements and RAI responses (References 3, 4, and 5).

St. Lucie Units 1 and 2 Dockets 50-335 and 50-389 PSL Response to NRC RAI No. B.2.3.27-1a L-2022-143 Attachment 1 Page 5 of 42

References:

1. NACE. Standard Practice SP0169-2007, Control of External Corrosion on Underground or Submerged Metallic Piping Systems. Houston, Texas: NACE International. 2007.

2. ASTM. ASTM D 448-08, Classification for Sizes of Aggregate for Road and Bridge Construction. West Conshohocken, Pennsylvania: ASTM International. 2008.

3. Florida Power and Light Company (FPL) Letter to NRC L-2022-075 dated June 13, 2022, [St. Lucie Units 1 and 2] Subsequent License Renewal Application - Aging Management Requests for Additional Information (RAI) Set 1A Response and Request for Confirmation of Information (RCI) Set 1 Response, ADAMS Accession No. ML22164A802

4. Florida Power and Light Company (FPL) Letter to NRC L-2022-043 dated April 7, 2022,

[St. Lucie Units 1 and 2] Subsequent License Renewal Application Revision 1 -

Supplement 1, ADAMS Accession No. ML22097A202

5. Florida Power and Light Company (FPL) Letter to NRC L-2022-115 dated August 9, 2022, [St. Lucie Units 1 and 2] Subsequent License Renewal Application - Aging Management Requests for Additional Information (RAI) Set 3 Response and Submittal of Superseded Response for One Set 2 RAI and One Supplement 1 Attachment, ADAMS Accession No. ML22221A134

St. Lucie Units 1 and 2 Dockets 50-335 and 50-389 PSL Response to NRC RAI No. B.2.3.27-1a L-2022-143 Attachment 1 Page 38 of 42

SLRA Section B.1.1, page B-6, as updated by Supplement 1 Attachments 10 and 18, is updated as follows:

x PSL Inspection of Internal Surfaces in Miscellaneous Piping and Ducting Components AMP (Section B.2.3.24),

x PSL Buried and Underground Piping and Tanks AMP (Section B.2.3.27),

x PSL Internal Coatings/Linings for In-Scope Piping, Piping Components, Heat Exchangers, and Tanks AMP (Section B.2.3.28),

x PSL Electrical Insulation for Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements used in Instrumentation Circuits AMP ( Section B.2.3.37),

x PSL Electrical Insulation for Inaccessible Medium-Voltage Power Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements AMP (Section B.2.3.38),

x PSL Electrical Insulation for Inaccessible Instrument and Control Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements AMP (Section B.2.3.39),

x PSL Electrical Insulation for Inaccessible Low-Voltage Power Cables Not Subject to 10 CFR 50.49 Environmental Qualification Requirements AMP (Section B.2.3.40),

x PSL Metal Enclosed Bus AMP (Section B.2.3.41),

x PSL Electrical Cable Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements AMP (Section B.2.3.42), and x PSL High-Voltage Insulators AMP (Section B.2.3.43).

These new AMPs will be consistent with the 10 elements of their respective NUREG-2191 AMPs.

The following programs each have exception(s) justified by technical data:

x PSL Reactor Head Closure Stud Bolting AMP (Section B.2.3.3),

x Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (Section B.2.3.6),

x PSL Steam Generators AMP (Section B.2.3.10),

x PSL Outdoor and Large Atmospheric Metallic Storage Tank AMP (Section B.2.3.17),

x PSL Fuel Oil Chemistry AMP (Section B.2.3.18),

x PSL Reactor Vessel Material Surveillance AMP (Section B.2.3.19),

x PSL Buried and Underground Piping and Tanks AMP (Section B.2.3.27),

x PSL ASME Section XI, Subsection IWF AMP (Section B.2.3.30), and x PSL Structures Monitoring AMP ( Section B.2.3.33)

B.1.2 Method of Discussion

For those PSL AMPs that are consistent with the AMP descriptions and assumptions made in Sections X and XI of NUREG-2191, or are consistent with exceptions or enhancements, each AMP discussion is presented in the following format:

x A Program Description abstract of the overall program form and function is provided. This Program Description also includes whether the program is existing (and if it replaces LR programs) or new for SLR.

St. Lucie Units 1 and 2 Dockets 50-335 and 50-389 PSL Response to NRC RAI No. B.2.3.27-1a L-2022-143 Attachment 1 Page 39 of 42

SLRA Table B-4, page B-21 is updated as follows:

Table B-4 PSL Aging Management Program Consistency with NUREG-2191 PSL Aging Section PSL NUREG-2191 Comparison Management Plant-Specific? NUREG-2191 Enhancements? Exceptions?

Program Section Fire Protection B.2.3.15 No XI.M26 Yes No Fire Water System B.2.3.16 No XI.M27 Yes No Outdoor and Large B.2.3.17 No XI.M29 Yes Yes Atmospheric Metallic Storage Tanks Fuel Oil Chemistry B.2.3.18 No XI.M30 Yes Yes Reactor Vessel B.2.3.19 No XI.M31 No Yes Material Surveillance One-Time Inspection B.2.3.20 No XI.M32 New No Selective Leaching B.2.3.21 No XI.M33 New No ASME Code Class 1 B.2.3.22 No XI.M35 No No Small-Bore Piping External Surfaces B.2.3.23 No XI.M36 Yes No Monitoring of Mechanical Components Inspection of Internal B.2.3.24 No XI.M38 New No Surfaces in Miscellaneous Piping and Ducting Components Lubricating Oil B.2.3.25 No XI.M39 Yes No Analysis Monitoring of B.2.3.26 No XI.M40 Yes No Neutron-Absorbing Materials Other Than Boraflex Buried and B.2.3.27 No XI.M41 New No Underground Piping Yes and Tanks Internal B.2.3.28 No XI.M42 New No Coatings/Linings for In-Scope Piping, Piping Components, Heat Exchangers, and Tanks ASME Section XI, B.2.3.29 No XI.S1 Yes No Subsection IWE ASME Section XI, B.2.3.30 No XI.S3 Yes Yes Subsection IWF 10 CFR Part 50, B.2.3.31 No XI.S4 No No Appendix J Masonry Walls B.2.3.32 No XI.S5 Yes No Structures B.2.3.33 No XI.S6 Yes Yes Monitoring

St. Lucie Units 1 and 2 Dockets 50-335 and 50-389 PSL Response to NRC RAI No. B.2.3.27-1a L-2022-143 Attachment 1 Page 40 of 42

SLRA Appendix B, Section B.2.3.27, page B-216, as updated by Supplement 1 Attachments 7 and 25, is updated as follows:

selected for buried steel piping after the cathodic protection system has been in service for approximately 10 years and annual effectiveness reviews are performed.

However, if these conditions were to change, the Preventive Action Category would require reevaluation and could potentially change.

The number of inspections for each 10-year inspection period, beginning 10 years before the SPEO, are based on the inspection quantities noted in NUREG-2191, Table XI.M41-2, adjusted for a 2-Unit plant site.

Material No. of Inspections Notes Steel (buried) 11* prior to the SPEO Includes 2 additional inspections to (Category F) meet the requirements of NUREG-2191 4 in each 10-year period in the Section XI.M41, paragraph 4.e.i SPEO (Category C) regarding the aging effects associated with fire mains.

Steel 3 (underground)

Stainless steel Pressure testing per note Perform periodic pressure testing (underground) and blow-out testing (purging) with air or nitrogen of the annular volume between the underground stainless steel fuel oil piping and its respective guard piping to verify no leakage of guard pipe and no leakage from the fuel oil piping. This testing will be performed for at least 25 percent of the stainless steel fuel oil piping housed within guard piping at an interval not to exceed 5 years with the first occurrence prior to the SPEO. The annular volume between the fuel oil piping and guard piping will be pressurized to 110 percent of the design pressure of any component within the boundary (not to exceed the maximum allowable test pressure of any non-isolated components) with test pressure being held for a continuous eight hour interval.

Stainless steel 2 (buried)

St. Lucie Units 1 and 2 Dockets 50-335 and 50-389 PSL Response to NRC RAI No. B.2.3.27-1a L-2022-143 Attachment 1 Page 41 of 42

• If after five years of operation the cathodic protection system does not meet the effectiveness acceptance criteria defined by NUREG-2191, Tables XI.M41-2 and -3 (-850 mV relative to a CSE, instant off, for at least 80 percent of the time, and in o peration for at least 85 percent of the time), FPL commits to performing two additional buried steel piping inspections beyond the number required by Preventive Action Category F resulting in a total of thirteen (13) inspections being completed six months prior to the SPEO. The cathodic protection criterion listed above will continue to be used after five years through the end of the SPEO.

This AMP does not provide aging management of selective leaching. The PSL Selective Leaching of Materials (Section B.2.3.21) AMP is applied in addition to this program for applicable materials and environments.

The PSL Buried and Underground Piping and Tanks AMP requires the creation of new governing and inspection procedures consistent with NUREG-2191,Section XI.M41, as well as a new sampling plan and work orders to support the new inspections. A new cathodic protection system will also be installed, and an effectiveness review per Table XI.M41-2 of NUREG-2191,Section XI.M41 will be performed throughout each of the 10-year inspection periods. Initial inspections begin 10 years before to the SPEO and are completed no later than six months prior to entering the SPEO or no later than the last RFO prior to the SPEO.

NUREG-2191 Consistency

The PSL Buried and Underground Piping and Tanks AMP will be consistent without exception to the 10 elements of NUREG-2191,Section XI.M41, Buried and Underground Piping and Tanks.

Exceptions to NUREG-2191

None. An exception to the NUREG-2191 recommendation of coating buried stainless steel as a preventive action will be taken with respect to the Unit 1 stainless steel AFW pump recirculation piping and condensate system (AFW pump suction) piping buried beneath the Unit 1 turbine building. This exception is justified due to the low number of chlorides within the soil, the low likelihood of stagnant moisture due to the concrete floor slab shielding, good soil/backfill drainage, and no history of negative OE for buried stainless steel piping at St. Lucie.

St. Lucie Units 1 and 2 Dockets 50-335 and 50-389 PSL Response to NRC RAI No. B.2.3.27-1a L-2022-143 Attachment 1 Page 42 of 42

Associated

Enclosures:

None.