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| {{#Wiki_filter:April 19, 2022 Ms. Patricia L. Skibbee Board President C-10 Research and Education Foundation 11 Chestnut Street Amesbury, MA 01913 | | {{#Wiki_filter:April 19, 2022 |
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| | Ms. Patricia L. Skibbee Board President C-10 Research and Education Foundation 11 Chestnut Street Amesbury, MA 01913 |
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| ==Dear Ms. Skibbee:== | | ==Dear Ms. Skibbee:== |
| | On behalf of the U.S. Nuclear Regulatory Commission (NRC), I am responding to your |
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| | email to the Seabrook Senior Resident Inspector on March 9, 2022, in which you requested |
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| | responses to several questions and concerns regarding the fourth quarter 2021 integr ated |
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| | inspection report (ADAMS Accession Num ber ML22040A204). Responses to the specific |
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| | questions are enclosed. |
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| | Sincerely, |
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| On behalf of the U.S. Nuclear Regulatory Commission (NRC), I am responding to your email to the Seabrook Senior Resident Inspector on March 9, 2022, in which you requested responses to several questions and concerns regarding the fourth quarter 2021 integrated inspection report (ADAMS Accession Number ML22040A204). Responses to the specific questions are enclosed.
| | Matt R. Young, Chief Projects B ran ch 2 Division of Operating Reactor Safety |
| Sincerely, Digitally signed by Matthew R.
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| Matthew R. Young Date: 2022.04.19 09:35:22 Young -04'00' Matt R. Young, Chief Projects Branch 2 Division of Operating Reactor Safety
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| ==Enclosure:== | | ==Enclosure:== |
| | As stated |
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| As stated
| | ML22109A034 |
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| | x Non-Sensitive x Publicly Available x SUNSI Review Sensitive Non-Publicly Available |
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| | OFFICE RI/ORA RI/DORS RI/DORS NAME DScrenci CNewport MYoung DATE 4/18/22 4/18/22 4/18/22 |
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| | U.S. Nuclear Regulatory Commission Response to Questions in the March 9, 2022, memorandum and email |
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| ML22109A034 x Non-Sensitive x Publicly Available x SUNSI Review Sensitive Non-Publicly Available OFFICE RI/ORA RI/DORS RI/DORS NAME DScrenci CNewport MYoung DATE 4/18/22 4/18/22 4/18/22 U.S. Nuclear Regulatory Commission Response to Questions in the March 9, 2022, memorandum and email As you requested, we are responding in writing to eight of the 17 questions you submitted to us.
| | As you requested, we are responding in writing to eight of the 17 questions you submitted to us. |
| We discussed the others during a telephone conversation on April 7. | | We discussed the others during a telephone conversation on April 7. |
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| Q1a. Was the cause of the initial failure ever determined? Was it an electrical issue due to faulty wiring? Was faulty wiring due to moisture penetration due to ASR? Was the cause an equipment failure? Are vendor(s) on call for repairing/replacing this system? | | Q1a. Was the cause of the initial failure ever determined? Was it an electrical issue due to faulty wiring? Was faulty wiring due to moisture penetration due to ASR? Was the cause an equipment failure? Are vendor(s) on call for repairing/replacing this system? |
| The cause of the initial failure was a failing voltage regulating module for the specific fire zone (RHR pump room, Zone #3) which consists of two smoke detectors. The RHR vaults contain one control panel with 10 zones (5 zones per vault). Each zone has a voltage regulating module that supplies 240 Volts of direct current (Vdc) to the associated detectors. Upon troubleshooting, the output voltage for the regulating module was found to be less than 45 Vdc. | | |
| | The cause of the initial failure was a failing voltage regulating module for the specific fire zone (RHR pump room, Zone #3) which consists of two smoke detectors. The RHR vaults contain one control panel with 10 zones (5 zones per vault). Each zone has a voltage regulating module that supplies 240 Volts of direct current (Vdc) to th e associated detectors. Upon troubleshooting, the output voltage for the regulating module was found to be less than 45 Vdc. |
| The fire detection system is a supervised system meaning that when the voltage module failed a trouble alarm was generated which provided trouble indication to the control room. The cause of the failed voltage regulating module was most likely due to normal component aging. The failure was not due to faulty wiring or water penetration into wiring. | | The fire detection system is a supervised system meaning that when the voltage module failed a trouble alarm was generated which provided trouble indication to the control room. The cause of the failed voltage regulating module was most likely due to normal component aging. The failure was not due to faulty wiring or water penetration into wiring. |
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| The station does have vendor contacts and routinely works with various vendors for fire detector and system upgrades. Plant maintenance technicians are also trained and qualified to perform preventive and corrective maintenance and testing on the fire detection systems at Seabrook. | | The station does have vendor contacts and routinely works with various vendors for fire detector and system upgrades. Plant maintenance technicians are also trained and qualified to perform preventive and corrective maintenance and testing on the fire detection systems at Seabrook. |
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| Q1d. How advanced is ASR in the RHR system and how has the fire protection program been modified for this factor? | | Q1d. How advanced is ASR in the RHR system and how has the fire protection program been modified for this factor? |
| The licensee has previously analyzed the impacts of ASR and ASR-related building deformation on the RHR vaults in a formal structural evaluation. In accordance with the structures monitoring program, Seabrook personnel conduct routine formal walkdowns of the RHR vaults inspecting for equipment impacts. Additionally, the NRC resident inspectors routinely conduct plant status walkdowns of both vaults. To date, there have not been any ASR-related impacts identified in any component of the fire protection systems in the RHR vaults. No modifications to the fire protection systems in the RHR vaults have been needed. | | |
| | The licensee has previously analyzed the impacts of ASR and ASR -related building deformation on the RHR vaults in a formal structural evaluation. In accordance with the structures monitoring program, Seabrook personnel conduct routine formal walkdowns of the RHR vaults inspecting for equipment impacts. Additionally, the NRC resident inspectors routinely conduct plant status walkdowns of both vaul ts. To date, there have not been any ASR -related im pacts identified in any component of the fire protection systems in the RHR vaults. No modifications to the fire protection systems in the RHR vaults have been needed. |
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| Q2a. Although the most likely source of the water was the refueling cavity and based upon the high pH, the observed surface corrosion did not have unacceptable effect on the structural integrity of the containment, in fact, no genuine assessment has yet taken place. This issue from the Spring refueling outage 2020 was pushed to Fall 2021 and now is further deferred to Spring 2023 (OR22). At what point in time will the NRC require a valid assessment? | | Q2a. Although the most likely source of the water was the refueling cavity and based upon the high pH, the observed surface corrosion did not have unacceptable effect on the structural integrity of the containment, in fact, no genuine assessment has yet taken place. This issue from the Spring refueling outage 2020 was pushed to Fall 2021 and now is further deferred to Spring 2023 (OR22). At what point in time will the NRC require a valid assessment? |
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| The characterization of a deferral of assessments is not borne out by our inspection results. | | The characterization of a deferral of assessments is not borne out by our inspection results. |
| The licensee performed technical assessments in both the spring 2020 and fall 2021 refueling outages, which we then inspected and documented in NRC inspection reports. The assessment in the fall 2021 refueling outage was updated with new information collected as a result of corrective actions planned and completed by the licensee from the spring 2020 outage. | | The licensee performed technical assessments in both the spring 2020 and fall 2021 refueling outages, which we then inspected and documented in NRC inspection reports. The assessment in the fall 2021 refueling outage was updated with new information collected as a result of corrective actions planned and completed by the licensee from the s pring 2020 outage. |
| The licensee has further plans to remove the caps of the containment leak chase liner system during the performance of the planned 15-year containment integrated leak rate test planned for Enclosure | | The licensee has further plans to remove the caps of the containment leak chase liner system during the performance of the planned 15-year containment integrated leak rate test planned for |
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| | Enclosure the next refueling outage in s pring 2023. NRC inspectors continue to verify that the licensee follows the requirements described in the NRC regulations and ASME Code. |
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| the next refueling outage in spring 2023. NRC inspectors continue to verify that the licensee follows the requirements described in the NRC regulations and ASME Code.
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| Q2b. If, as noted, the surface corrosion of the containment liner is deemed to NOT be due to water most likely leaking from the refueling cavity, then what IS causing the observed surface corrosion of the liner and on what basis did the NRC determine that corrosion did not affect the integrity of the liner? | | Q2b. If, as noted, the surface corrosion of the containment liner is deemed to NOT be due to water most likely leaking from the refueling cavity, then what IS causing the observed surface corrosion of the liner and on what basis did the NRC determine that corrosion did not affect the integrity of the liner? |
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| NRC inspectors reviewed a sample of the licensees visual inspections via borescope through the leak chase channel test connections as well as the licensees documented corrosion analysis. The inspectors confirmed by inspection activities that there is water in the containment leak chase cavity system. The identified corrosion was limited to the surface of the metal and did not show any significant loss of material. The corrosion analysis supported this visual evidence and provided a reasonable basis for integrity of the metal liner. In reaching conclusions related to the adequacy of the licensees assessment of integrity of the leak chases, the inspectors considered the results of their interviews with plant staff, their independent review of plant records showing visual examination results of portions of the leak chases, and water chemistry sample results. As stated in our inspection report, the inspectors considered, in particular, the chemistry results showing high water pH which would preclude significant corrosion of the liner metal. Additionally, the inspectors noted that continued augmented monitoring by NextEra staff was an appropriate corrective action to verify their conclusions that the source of the water was from the refueling cavity. | | NRC inspectors reviewed a sample of the licensees visual inspections via borescope through the leak chase channel test connections as well as the licensees documented corrosion analysis. The inspectors confirmed by inspection activities that there is water in the containment leak chase cavity system. The identified corrosion was limited to the surface of the metal and did not show any significant loss of material. The corrosion analysis supported this visual evidence and provided a reasonable basis for integrity of the metal liner. In reaching conclusions related to the adequacy of the licensees assessment of integrity of the leak chases, the inspectors considered the results of their interviews with plant staff, their independent review of plant records showing visual examination results of portions of the leak chases, and water chemistry sample results. As stated in our inspection report, the inspectors considered, in particular, the chemistry results showing high water pH which would preclude significant corrosion of the liner metal. Additionally, the inspectors noted that continued augmented monitoring by NextEra staff was an appropriate corrective action to verify their conclusions that the source of the water was from the refueling cavity. |
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| Q3b. After the myriad of measuring and reporting failures by NextEra noted above, did the NRC staff complete their own 2021 data measurements on the CIS and compare them directly to NextEras 2021 data results? | | Q3b. After the myriad of measuring and reporting failures by NextEra noted above, did the NRC staff complete their own 2021 data measurements on the CIS and compare them directly to NextEras 2021 data results? |
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| NRC inspection activities documented in our fourth quarter 2021 NRC inspection report identified an instance where structural monitoring measurements of the Seabrook containment internal structure were not properly evaluated in accordance with the licensees structural monitoring program. During the spring 2021 refueling outage, NRC inspectors conducted independent walkdowns of the containment internal structure area of containment. As part of this walkdown the inspectors independently took photographs and measurements of multiple areas of the structure. The inspectors measurements were consistent with the licensees documented data measurements. | | NRC inspection activities documented in our fourth quarter 2021 NRC inspection report identified an instance where structural monitoring measurements of the Seabrook containment internal structure were not properly evaluated in accordance with the licensees structural monitoring program. During the spring 2021 refueling outage, NRC inspectors conducted independent walkdowns of the containment internal structure area of containment. As part of this walkdown the inspectors independently took photographs and measurements of multiple areas of the structure. The inspectors measurements were consistent with the licensees documented data measurements. |
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| Q3e. Please define/quantify both a reasonable ASR expansion and the indications observed as noted above? Please provide the results of the more detailed finite element analysis conducted? | | Q3e. Please define/quantify both a reasonable ASR expansion and the indications observed as noted above? Please provide the results of the more detailed finite element analysis conducted? |
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| A reasonable ASR expansion refers to the NRCs assessment that NextEra assumed an appropriate amount of expansion for the listed structures based on the identified indications of ASR to conclude the structures remained capable of performing as intended. Indications observed refers to two horizontal cracks (~1/8 at their widest points) in the reactor cavity pit East keyway cavity opening, a series of small horizontal cracks (~0.01) on the East wall of the North extension area, and bowing of a floor deck grating with spalling of adjacent cover concrete of the floor slab perpendicular to the East wall of the North extension area. | | A reasonable ASR expansion refers to the NRCs assessment that NextEra assumed an appropriate amount of expansion for the listed structures based on the identified indications of ASR to conclude the structures remained capable of performing as intended. Indications observed refers to two horizontal cracks (~1/8 at their widest points) in the reactor cavity pit East keyway cavity opening, a series of small horizontal cracks (~0.01) on the East wall of the North extension area, and bowing of a floor deck grating with spalling of adjacent cover concrete of the floor slab perpendicular to the East wall of the North extension area. |
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| A more detailed finite element analysis (Stage 2 building deformation analysis) is currently being completed by the licensee and its engineering contractor. The NRC will perform a detailed review of this analysis and any associated corrective actions when completed. The results of our review will be documented in a future inspection report. | | 2 A more detailed finite element analysis (Stage 2 building deformation analysis) is currently being completed by the licensee and its engineering contractor. The NRC will perform a detailed review of this analysis and any associated corrective actions when completed. The results of our review will be documented in a future inspection report. |
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| Q4a. Why were NextEras October 4, 2021 general area dose rates up to 150 mrem/hr (usually 6-8 mrem/hr) two days after the plant shutdown on October 2, 2021? | | Q4a. Why were NextEras October 4, 2021 general area dose rates up to 150 mrem/hr (usually 6-8 mrem/hr) two days after the plant shutdown on October 2, 2021? |
| A large portion of the components of both trains of the RHR system are housed within the RHR vaults. In addition to use as an emergency core cooling system during a large break loss of coolant accident to inject water into the core, the RHR system is used during outages in the shutdown cooling mode to circulate water through the reactor coolant system and remove decay heat from the fuel. During this mode of operation, activated wear products found within the reactor coolant system circulate through the piping and valves within the RHR vaults and increase the dose rates in the general vicinity. | | |
| | A large portion of the components of both trains of the RHR system are housed within the RHR vaults. In addition to use as an e mergency core cooling system during a large break loss of coolant accident to inject water into the core, the RHR system is used during outages in the shutdown cooling mode to circulate water through the reactor coolant system and remove decay heat from the fuel. During this mode of operation, activated wear products found within the reactor coolant system circulate through the piping and valves within the RHR vaults and increase the dose rates in the general vicinity. |
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| Q4b. What are the details for NextEras Radiation Work permit 0101 for the A and B RHR vaults that were to be performed by the individual exposed to high radiation levels on October 5, 2021? | | Q4b. What are the details for NextEras Radiation Work permit 0101 for the A and B RHR vaults that were to be performed by the individual exposed to high radiation levels on October 5, 2021? |
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| Radiation Work Permit (RWP) 0101 is used for general management and inspector walkdowns during outages. Task 20 of the RWP, used by the individual on October 5, 2021, allows access to radiation and high radiation areas for inspector walkdowns, but cannot be used to perform physical work. The alarm setpoints associated with Task 20 were 10 mrem dose and 50 mrem/hr dose rate. The individual that is mentioned in the report was an NRC inspector performing walkdowns of the RHR system and upon exiting the area noted that they had received 4.2 mrem of dose with a maximum dose rate of 47 mrem/hr. | | Radiation Work Permit (RWP) 0101 is used for general management and inspector walkdowns during outages. Task 20 of the RWP, used by the individual on October 5, 2021, allows access to radiation and high radiation areas for inspector walkdowns, but cannot be used to perform physical work. The alarm setpoints associated with Task 20 were 10 mrem dose and 50 mrem/hr dose rate. The individual that is mentioned in the report was an NRC inspector performing walkdowns of the RHR system and upon exiting the area noted that they had received 4.2 mrem of dose with a maximum dose rate of 47 mrem/hr. |
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Category:Letter
MONTHYEARIR 05000443/20240032024-10-30030 October 2024
Integrated Inspection Report 05000443/2024003
L-2024-176, Annual 10 CFR 140.21 Licensee Guarantees of Payment of Deferred Premiums2024-10-30030 October 2024
Annual 10 CFR 140.21 Licensee Guarantees of Payment of Deferred Premiums
ML24303A0352024-10-29029 October 2024
Operator Licensing Examination Approval
IR 05000443/20244022024-10-17017 October 2024
Material Control and Accounting Program Inspection Report 05000443/2024402 (Cover Letter Only)
L-2024-159, Core Operating Limits Report for Reload Cycle 242024-10-15015 October 2024
Core Operating Limits Report for Reload Cycle 24
L-2024-169, Supplement to License Amendment Request to Adopt Common Emergency Plan with Site- Specific Annexes2024-10-15015 October 2024
Supplement to License Amendment Request to Adopt Common Emergency Plan with Site- Specific Annexes
ML24254A2552024-09-25025 September 2024
Alternative Request No. 4A-01 for the Fourth 10-Year Inservice Inspection Interval
L-2024-158, Supplemental Information to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes2024-09-25025 September 2024
Supplemental Information to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes
ML24239A5382024-09-20020 September 2024
Issuance of Amendment No. 175 One-Time Allowable Outage Time Extension to the Technical Specification 3.8.1.1, A.C. Sources – Operating, Limiting Condition for Operation
L-2024-136, Supplement to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes2024-09-16016 September 2024
Supplement to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes
IR 05000443/20240052024-08-29029 August 2024
Updated Inspection Plan for Seabrook Station (Report 05000443/2024005)
ML24232A1142024-08-21021 August 2024
Correction to Amendment No. 174 to Update the Period of Applicability (Poa) for the Pressure-Temperature Limits (PTL) and Low Temperature Overpressure Protection (LTOP) Curves
L-2024-141, Third Supplement to NextEra Energy Seabrook, LLC, Letter L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent Circuit2024-08-15015 August 2024
Third Supplement to NextEra Energy Seabrook, LLC, Letter L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent Circuit Be
L-2024-137, Second Supplement to NextEra Energy Seabrook, LLC, Letter L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent .2024-08-12012 August 2024
Second Supplement to NextEra Energy Seabrook, LLC, Letter L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent .
IR 05000443/20240022024-08-0606 August 2024
Integrated Inspection Report 05000443/2024002 and Independent Spent Fuel Storage Installation Inspection Report 07200063/2024001
L-2024-127, Supplement to Letter L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent2024-08-0505 August 2024
Supplement to Letter L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent
ML24163A0012024-08-0505 August 2024
LTR-24-0119-1-1 Response to Nh Letter Regarding Review of NextEras Emergency Preparedness Amendment Review
L-2024-125, Notice of Intent to Provide Supplemental Information to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes2024-07-24024 July 2024
Notice of Intent to Provide Supplemental Information to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes
L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent Circuit Between the Offsite.2024-07-16016 July 2024
Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent Circuit Between the Offsite.
ML24193A2432024-07-12012 July 2024
– Interim Audit Summary Report in Support of Review of License Amendment Requests Regarding Fleet Emergency Plan
L-2024-114, Quality Assurance Topical Report (FPL-1 Revision 31 Annual Submittal2024-07-10010 July 2024
Quality Assurance Topical Report (FPL-1 Revision 31 Annual Submittal
L-2024-102, Official Service List Update2024-06-19019 June 2024
Official Service List Update
ML24149A2862024-06-12012 June 2024
NextEra Fleet - Proposed Alternative Frr 23-01 to Use ASME Code Case N-752-1, Risk-Informed Categorization and Treatment for Repair/Replacement Activities in Class 2 and 3 Systems Section X1, Division 1 (EPID L-2023-LLR-0009) - Letter
L-2024-098, Preparation and Scheduling of Operator Licensing Examinations2024-06-12012 June 2024
Preparation and Scheduling of Operator Licensing Examinations
L-2024-084, Relief Request 4A-01, Rev 1 - Revision to Relief Request for Examination of Control Rod Drive Mechanism (Rod) Housing H-4 Canopy Seal Weld2024-05-30030 May 2024
Relief Request 4A-01, Rev 1 - Revision to Relief Request for Examination of Control Rod Drive Mechanism (Rod) Housing H-4 Canopy Seal Weld
IR 05000443/20240102024-05-29029 May 2024
Biennial Problem Identification and Resolution Inspection Report 05000443/2024010
IR 05000443/20240112024-05-24024 May 2024
Age-Related Degradation Inspection Report 05000443/2024011
IR 05000443/20240012024-05-13013 May 2024
Integrated Inspection Report 05000443/2024001
L-2024-061, NextEra Energy Seabrook, LLC, License Amendment Request - One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent Circuit Between the Offsite Transmission Network and the Onsite Class 1E Distribut2024-05-10010 May 2024
NextEra Energy Seabrook, LLC, License Amendment Request - One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent Circuit Between the Offsite Transmission Network and the Onsite Class 1E Distributio
ML24046A0512024-05-0707 May 2024
Issuance of Amendment No. 174 to Update the Period of Applicability (Poa) for the Pressure-Temperature Limits (PTL) and Low Temperature Overpressure Protection (LTOP) Curves
ML24127A0632024-05-0606 May 2024
Supplemental Information to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes
L-2024-078, 2023 Annual Radioactive Effluent Release Report2024-05-0101 May 2024
2023 Annual Radioactive Effluent Release Report
L-2024-077, 2023 Annual Radiological Environmental Operating Report2024-04-30030 April 2024
2023 Annual Radiological Environmental Operating Report
IR 05000443/20245012024-04-22022 April 2024
Emergency Preparedness Biennial Exercise Inspection Report 05000443/2024501
05000443/LER-2024-001, Condition Prohibited by Technical Specifications - Transformer Bushing Failure - Offsite AC Sources2024-04-19019 April 2024
Condition Prohibited by Technical Specifications - Transformer Bushing Failure - Offsite AC Sources
SBK-L-24030, 2023 Annual Environmental Operating Report2024-04-12012 April 2024
2023 Annual Environmental Operating Report
L-2024-011, And Point Beach, Units 1 and 2 - 10 CFR 50.46 Annual Reporting of Changes to, or Errors in Emergency Core Cooling System Models or Applications2024-03-13013 March 2024
And Point Beach, Units 1 and 2 - 10 CFR 50.46 Annual Reporting of Changes to, or Errors in Emergency Core Cooling System Models or Applications
L-2024-038, To Seabrook Emergency License Amendment Request - One Time Extension to Technical Specifications (TS) 3/4.8.1 Action a.3 Allowed Outage Time for an Inoperable Offsite Source2024-03-0808 March 2024
To Seabrook Emergency License Amendment Request - One Time Extension to Technical Specifications (TS) 3/4.8.1 Action a.3 Allowed Outage Time for an Inoperable Offsite Source
ML24067A2622024-03-0808 March 2024
Issuance of Amendment No. 173 Revise Technical Specification 3/4.8.1 to Allow Replacement of Reserve Auxiliary Transformer (Emergency Circumstances)
L-2024-037, To Seabrook Emergency License Amendment Request - One Time Extension to Technical Specifications (TS) 3/4.8.1 Action a.3 Allowed Outage Time for an Inoperable Offsite Source2024-03-0606 March 2024
To Seabrook Emergency License Amendment Request - One Time Extension to Technical Specifications (TS) 3/4.8.1 Action a.3 Allowed Outage Time for an Inoperable Offsite Source
ML24065A2522024-03-0505 March 2024
Notice of Enforcement Discretion for Seabrook Station, Unit No. 1 (EPID: L-2024-033)
L-2024-035, Supplement to Seabrook Emergency License Amendment Request - One Time Extension to Technical Specifications (TS) 3/4.8.1 Action a.3 Allowed Outage Time for an Inoperable Offsite Source2024-03-0505 March 2024
Supplement to Seabrook Emergency License Amendment Request - One Time Extension to Technical Specifications (TS) 3/4.8.1 Action a.3 Allowed Outage Time for an Inoperable Offsite Source
L-2024-033, Request for Enforcement Discretion - Technical Specification (TS) 3/4.8.1.1 Ac. Sources Required Action Completion Time to Replace ED-X-3-B2024-03-0404 March 2024
Request for Enforcement Discretion - Technical Specification (TS) 3/4.8.1.1 Ac. Sources Required Action Completion Time to Replace ED-X-3-B
L-2024-032, Emergency License Amendment Request- One Time Extension to Technical Specifications (TS) 3/4.8.1 Action a.3 Allowed Outage Time for an Inoperable Offsite Source2024-03-0404 March 2024
Emergency License Amendment Request- One Time Extension to Technical Specifications (TS) 3/4.8.1 Action a.3 Allowed Outage Time for an Inoperable Offsite Source
IR 05000443/20230062024-02-28028 February 2024
Annual Assessment Letter for Seabrook Station (Report 05000443/2023006)
L-2024-019, Relief Request 4A-01- Request for an Alternative to the Requirements of the ASME Code for Examination of Control Rod Drive Mechanism (Rod) Housing H-4 Canopy Seal Weld2024-02-28028 February 2024
Relief Request 4A-01- Request for an Alternative to the Requirements of the ASME Code for Examination of Control Rod Drive Mechanism (Rod) Housing H-4 Canopy Seal Weld
L-2024-016, Radiological Emergency Plan (Ssrep), Revision 822024-02-13013 February 2024
Radiological Emergency Plan (Ssrep), Revision 82
IR 05000443/20230042024-02-12012 February 2024
Integrated Inspection Report 05000443/2023004
ML24009A1152024-01-29029 January 2024
– Exemption from Select Requirements of 10 CFR Part 73 (EPID L 2023 LLE-0043 (Security Notifications, Reports, and Recordkeeping and Suspicious Activity Reporting))
L-2024-010, Point Units 3 and 4, Seabrook, Duane Arnold, and Point Beach Units 1 and 2, Nuclear Property Insurance - 10 CFR 50.54(w)(3)2024-01-25025 January 2024
Point Units 3 and 4, Seabrook, Duane Arnold, and Point Beach Units 1 and 2, Nuclear Property Insurance - 10 CFR 50.54(w)(3)
2024-09-25
[Table view]
Category:Response to Request for Additional Information (RAI)
MONTHYEARL-2024-136, Supplement to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes2024-09-16016 September 2024
Supplement to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes
L-2024-141, Third Supplement to NextEra Energy Seabrook, LLC, Letter L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent Circuit2024-08-15015 August 2024
Third Supplement to NextEra Energy Seabrook, LLC, Letter L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent Circuit Be
L-2024-137, Second Supplement to NextEra Energy Seabrook, LLC, Letter L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent .2024-08-12012 August 2024
Second Supplement to NextEra Energy Seabrook, LLC, Letter L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent .
L-2024-108, Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent Circuit Between the Offsite.2024-07-16016 July 2024
Response to Request for Additional Information (RAI) Regarding One Time Extension to Technical Specification 3.8.1.1.a, Allowed Outage Time with One Independent Circuit Between the Offsite.
ML24127A0632024-05-0606 May 2024
Supplemental Information to License Amendment Request to Adopt Common Emergency Plan with Site-Specific Annexes
L-2023-155, Supplement to Response to Request for Additional Information, Revised NextEra Common Emergency Plan, and Revised Site-Specific Emergency Plan Annexes Regarding License Amendment Request for Common Emergency Plan Consistent with NUREG-06542023-11-28028 November 2023
Supplement to Response to Request for Additional Information, Revised NextEra Common Emergency Plan, and Revised Site-Specific Emergency Plan Annexes Regarding License Amendment Request for Common Emergency Plan Consistent with NUREG-0654,
L-2023-098, And Point Beach Units 1 and 2 - Response to Request for Additional Information Regarding License Amendment Request for Common Emergency Plan Consistent with NUREG-0654, Revision 22023-08-0707 August 2023
And Point Beach Units 1 and 2 - Response to Request for Additional Information Regarding License Amendment Request for Common Emergency Plan Consistent with NUREG-0654, Revision 2
L-2023-005, Response to Request for Additional Information for Seabrook Relief Request 4RA-22-0012023-01-26026 January 2023
Response to Request for Additional Information for Seabrook Relief Request 4RA-22-001
ML22307A1682022-11-0303 November 2022
Cover Memo and Response to C-10 Questions Regarding 2Q2022 Inspection Report - Corrected
L-2022-157, Response to Request for Additional Information Regarding Seabrook Steam Generator Tube Inspection Report2022-09-28028 September 2022
Response to Request for Additional Information Regarding Seabrook Steam Generator Tube Inspection Report
L-2022-106, Revised Response to Request for Additional Information (RAI) Regarding License Amendment Request 21-01, Revise 120-Volt AC Vital Instrument Panel Requirements2022-06-27027 June 2022
Revised Response to Request for Additional Information (RAI) Regarding License Amendment Request 21-01, Revise 120-Volt AC Vital Instrument Panel Requirements
ML22109A0342022-04-19019 April 2022
Cover Memo and Response to C-10 Questions Regarding 4Q2021 Inspection Report
SBK-L-22024, Response to Request for Additional Information (Raj) Regarding License Amendment Request 21-01, Revise 120-Volt AC Vital Instrument Panel Requirements2022-03-0707 March 2022
Response to Request for Additional Information (Raj) Regarding License Amendment Request 21-01, Revise 120-Volt AC Vital Instrument Panel Requirements
ML21280A2622021-10-0707 October 2021
Response Letter to N. Treat (C-10 Research and Education Foundation) Regarding 2Q 2021 Integrated Inspection Report Questions
SBK-L-21049, Revision to Updated Final Response to NRC Generic Letter 2004-022021-06-24024 June 2021
Revision to Updated Final Response to NRC Generic Letter 2004-02
SBK-L-21056, Response to Request for Additional Information Regarding Seabrook Steam Generator Tube Inspection Report Review References:2021-05-20020 May 2021
Response to Request for Additional Information Regarding Seabrook Steam Generator Tube Inspection Report Review References:
SBK-L-21033, Response to Request for Additional Information (RAI) Regarding License Amendment Request (LAR) 20-02, Resolve Non-Conservative Heat Flux Hot Channel Factor (Fo(Z)) Requirements2021-03-24024 March 2021
Response to Request for Additional Information (RAI) Regarding License Amendment Request (LAR) 20-02, Resolve Non-Conservative Heat Flux Hot Channel Factor (Fo(Z)) Requirements
SBK-L-20149, Response to Request for Additional Information in Respect to One-Time Exemption from 10 CFR 73, Appendix B, Section VI, Subsection C.3.(I)(1) Regarding Annual Force-on-Force (FOF) Exercises, Due to Covid 19 Pandemic2020-12-0808 December 2020
Response to Request for Additional Information in Respect to One-Time Exemption from 10 CFR 73, Appendix B, Section VI, Subsection C.3.(I)(1) Regarding Annual Force-on-Force (FOF) Exercises, Due to Covid 19 Pandemic
SBK-L-20117, Response to Request for Additional Information Regarding Technical Specification 3/4.8.1 for a One-Time Extension of Allowed Outage Time License Amendment Request2020-09-23023 September 2020
Response to Request for Additional Information Regarding Technical Specification 3/4.8.1 for a One-Time Extension of Allowed Outage Time License Amendment Request
SBK-L-20092, Response to Request for Additional Information Regarding License Amendment Requests to Adopt TSTF-411 and TSTF-4182020-07-13013 July 2020
Response to Request for Additional Information Regarding License Amendment Requests to Adopt TSTF-411 and TSTF-418
SBK-L-20057, Response to Request for Additional Information Regarding Degraded Voltage Time Delay Setpoint License Amendment Request2020-05-20020 May 2020
Response to Request for Additional Information Regarding Degraded Voltage Time Delay Setpoint License Amendment Request
SBK-L-19120, Response to Request for Additional Information Related to Seabrook Inverter Amendment2019-10-30030 October 2019
Response to Request for Additional Information Related to Seabrook Inverter Amendment
SBK-L-18106, Response to Requests for Additional Information Related to License Renewal Application Environmental Review2018-06-14014 June 2018
Response to Requests for Additional Information Related to License Renewal Application Environmental Review
SBK-L-18074, Response to Request for Additional Information Regarding License Amendment Request 16-032018-06-0707 June 2018
Response to Request for Additional Information Regarding License Amendment Request 16-03
L-2018-068, Florida Power and Light Co. - Response to Request for Additional Information Re Decommissioning Funding Plan Updates for Independent Spent Fuel Storage Installations2018-04-0303 April 2018
Florida Power and Light Co. - Response to Request for Additional Information Re Decommissioning Funding Plan Updates for Independent Spent Fuel Storage Installations
SBK-L-18028, 0 - Response to Final Requests for Additional Information for the Safety Review of the Seabrook Station License Renewal Application - ASME Section XI, Subsection Iwl Program2018-02-28028 February 2018
0 - Response to Final Requests for Additional Information for the Safety Review of the Seabrook Station License Renewal Application - ASME Section XI, Subsection Iwl Program
SBK-L-18027, Supplement 59 - Response to Final Requests for Additional Information for the Safety Review of the Seabrook Station License Renewal Application - 10 CFR 50 Appendix J Program2018-02-28028 February 2018
Supplement 59 - Response to Final Requests for Additional Information for the Safety Review of the Seabrook Station License Renewal Application - 10 CFR 50 Appendix J Program
SBK-L-17202, Response to Seabrook Station, Unit No. 1 - Supplemental Information Needed for Acceptance of Requested Licensing Action Amendment to Delete Operator Action and Request for Exemption2017-12-14014 December 2017
Response to Seabrook Station, Unit No. 1 - Supplemental Information Needed for Acceptance of Requested Licensing Action Amendment to Delete Operator Action and Request for Exemption
SBK-L-17204, Response to Request for Additional Information Regarding License Amendment Request Related to Alkali-Silica Reaction (CAC No. MF8260; EPID L-2016-LLA-0007)2017-12-11011 December 2017
Response to Request for Additional Information Regarding License Amendment Request Related to Alkali-Silica Reaction (CAC No. MF8260; EPID L-2016-LLA-0007)
SBK-L-17180, Supplement 58, Revised Alkali-Silica Reaction Aging Management Program2017-11-0303 November 2017
Supplement 58, Revised Alkali-Silica Reaction Aging Management Program
SBK-L-17169, Supplement 58 - Non-Proprietary Enclosure 1 to SBK-L-171552017-10-17017 October 2017
Supplement 58 - Non-Proprietary Enclosure 1 to SBK-L-17155
SBK-L-17170, Non-Proprietary Enclosure 1 to SBK-L-171562017-10-17017 October 2017
Non-Proprietary Enclosure 1 to SBK-L-17156
SBK-L-17156, Response to Request for Additional Information Regarding License Amendment Request 16-03 Related to Alkali-Silica Reaction2017-10-0303 October 2017
Response to Request for Additional Information Regarding License Amendment Request 16-03 Related to Alkali-Silica Reaction
SBK-L-17155, Supplement 58 - Response to Request for Additional Information for the Review of the License Renewal Application - Building Deformation Analyses Related to Concrete Alkali-Silica Reaction2017-10-0303 October 2017
Supplement 58 - Response to Request for Additional Information for the Review of the License Renewal Application - Building Deformation Analyses Related to Concrete Alkali-Silica Reaction
SBK-L-17133, Clarification to Supplement 55 - Response to Request for Additional Information for the Review of the Seabrook Station License Renewal Application - Bolting Integrity Program2017-08-11011 August 2017
Clarification to Supplement 55 - Response to Request for Additional Information for the Review of the Seabrook Station License Renewal Application - Bolting Integrity Program
SBK-L-17103, Supplement 55 - Response to Request for Additional Information for the Review of the License Renewal Application - Bolting Integrity Program2017-06-20020 June 2017
Supplement 55 - Response to Request for Additional Information for the Review of the License Renewal Application - Bolting Integrity Program
SBK-L-17087, Supplement 53 - Response to Request for Additional Information for the Review of the Seabrook Station License Renewal Application - LR-ISG-2016-01 - Changes to Aging Management Guidance for Various Steam Generator Components2017-05-25025 May 2017
Supplement 53 - Response to Request for Additional Information for the Review of the Seabrook Station License Renewal Application - LR-ISG-2016-01 - Changes to Aging Management Guidance for Various Steam Generator Components
SBK-L-17082, Response to Request for Additional Information for the Review of the Seabrook Station License Renewal Application - LR-ISG-2016-01 -Changes to Aging Management Guidance for Various Steam Generator Components2017-05-19019 May 2017
Response to Request for Additional Information for the Review of the Seabrook Station License Renewal Application - LR-ISG-2016-01 -Changes to Aging Management Guidance for Various Steam Generator Components
SBK-L-17063, Response to Request for Additional Information Regarding License Amendment Request 17-01 One-Time Exigent Change to the Seabrook Licensing Basis Regarding Service Water Cooling Tower Functionality2017-04-0808 April 2017
Response to Request for Additional Information Regarding License Amendment Request 17-01 One-Time Exigent Change to the Seabrook Licensing Basis Regarding Service Water Cooling Tower Functionality
SBK-L-16205, Response to Request for Supplemental Information Regarding License Amendment Request 16-01, Request to Extend Containment Leakage Test Frequency and EMCB-RAI-22016-12-30030 December 2016
Response to Request for Supplemental Information Regarding License Amendment Request 16-01, Request to Extend Containment Leakage Test Frequency and EMCB-RAI-2
SBK-L-16196, Response to Request for Supplemental Information Regarding License Amendment Request 15-02, Adoption of Emergency Action Level Schemes Pursuant to NEI 99-01, Revision 6, Development of Emergency Action Levels for Non-Passive...2016-12-15015 December 2016
Response to Request for Supplemental Information Regarding License Amendment Request 15-02, Adoption of Emergency Action Level Schemes Pursuant to NEI 99-01, Revision 6, Development of Emergency Action Levels for Non-Passive...
SBK-L-16186, Supplement 50, Response to Request for Additional Information for the Review of License Renewal Application Providing Changes to Buried and Underground Piping and Tank Recommendations2016-11-23023 November 2016
Supplement 50, Response to Request for Additional Information for the Review of License Renewal Application Providing Changes to Buried and Underground Piping and Tank Recommendations
SBK-L-16190, Response to Request for Supplemental Information Regarding License Amendment Request 16-01, Request to Extend Containment Leakage Test Frequency2016-11-17017 November 2016
Response to Request for Supplemental Information Regarding License Amendment Request 16-01, Request to Extend Containment Leakage Test Frequency
ML16314D4272016-11-0707 November 2016
Response to NRC 10 CFR 50.54(f) Request for Information Regarding Near-Term Task Force Recommendation 2.1, Flooding - Submittal of Flooding Hazards Reevaluation Report, Revision 1
L-2016-188, Response to Generic Letter 2016-01, Monitoring of Neutron Absorbing Materials in Spent Fuel Pools, Response to NRC Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f)2016-11-0303 November 2016
Response to Generic Letter 2016-01, Monitoring of Neutron Absorbing Materials in Spent Fuel Pools, Response to NRC Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f)
SBK-L-16162, Response to Request for Additional Information Regarding License Amendment Request 15-02, Adoption of Emergency Action Level Schemes Pursuant to NEI 99-01, Revision 6, Development of Emergency Action Levels for Non-Passive Reactors2016-10-27027 October 2016
Response to Request for Additional Information Regarding License Amendment Request 15-02, Adoption of Emergency Action Level Schemes Pursuant to NEI 99-01, Revision 6, Development of Emergency Action Levels for Non-Passive Reactors
SBK-L-16170, Response to Request for Additional Information for the 04/22/2016 Steam Generator Tube Inspection Report2016-10-27027 October 2016
Response to Request for Additional Information for the 04/22/2016 Steam Generator Tube Inspection Report
SBK-L-16165, Response to RAI Regarding License Amendment Request 16-01, Request to Extend Containment Leakage Test Frequency2016-10-27027 October 2016
Response to RAI Regarding License Amendment Request 16-01, Request to Extend Containment Leakage Test Frequency
SBK-L-16156, Response to Issuance of LR-ISG-2015-01 Changes to Buried and Underground Piping and Tank Recommendations2016-10-0707 October 2016
Response to Issuance of LR-ISG-2015-01 Changes to Buried and Underground Piping and Tank Recommendations
SBK-L-16134, Response to RAI Related to Severe Accident Mitigation Alternatives License Renewal Application2016-09-0606 September 2016
Response to RAI Related to Severe Accident Mitigation Alternatives License Renewal Application
2024-09-16
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Text
April 19, 2022
Ms. Patricia L. Skibbee Board President C-10 Research and Education Foundation 11 Chestnut Street Amesbury, MA 01913
Dear Ms. Skibbee:
On behalf of the U.S. Nuclear Regulatory Commission (NRC), I am responding to your
email to the Seabrook Senior Resident Inspector on March 9, 2022, in which you requested
responses to several questions and concerns regarding the fourth quarter 2021 integr ated
inspection report (ADAMS Accession Num ber ML22040A204). Responses to the specific
questions are enclosed.
Sincerely,
Matt R. Young, Chief Projects B ran ch 2 Division of Operating Reactor Safety
Enclosure:
As stated
ML22109A034
x Non-Sensitive x Publicly Available x SUNSI Review Sensitive Non-Publicly Available
OFFICE RI/ORA RI/DORS RI/DORS NAME DScrenci CNewport MYoung DATE 4/18/22 4/18/22 4/18/22
U.S. Nuclear Regulatory Commission Response to Questions in the March 9, 2022, memorandum and email
As you requested, we are responding in writing to eight of the 17 questions you submitted to us.
We discussed the others during a telephone conversation on April 7.
Q1a. Was the cause of the initial failure ever determined? Was it an electrical issue due to faulty wiring? Was faulty wiring due to moisture penetration due to ASR? Was the cause an equipment failure? Are vendor(s) on call for repairing/replacing this system?
The cause of the initial failure was a failing voltage regulating module for the specific fire zone (RHR pump room, Zone #3) which consists of two smoke detectors. The RHR vaults contain one control panel with 10 zones (5 zones per vault). Each zone has a voltage regulating module that supplies 240 Volts of direct current (Vdc) to th e associated detectors. Upon troubleshooting, the output voltage for the regulating module was found to be less than 45 Vdc.
The fire detection system is a supervised system meaning that when the voltage module failed a trouble alarm was generated which provided trouble indication to the control room. The cause of the failed voltage regulating module was most likely due to normal component aging. The failure was not due to faulty wiring or water penetration into wiring.
The station does have vendor contacts and routinely works with various vendors for fire detector and system upgrades. Plant maintenance technicians are also trained and qualified to perform preventive and corrective maintenance and testing on the fire detection systems at Seabrook.
Q1d. How advanced is ASR in the RHR system and how has the fire protection program been modified for this factor?
The licensee has previously analyzed the impacts of ASR and ASR -related building deformation on the RHR vaults in a formal structural evaluation. In accordance with the structures monitoring program, Seabrook personnel conduct routine formal walkdowns of the RHR vaults inspecting for equipment impacts. Additionally, the NRC resident inspectors routinely conduct plant status walkdowns of both vaul ts. To date, there have not been any ASR -related im pacts identified in any component of the fire protection systems in the RHR vaults. No modifications to the fire protection systems in the RHR vaults have been needed.
Q2a. Although the most likely source of the water was the refueling cavity and based upon the high pH, the observed surface corrosion did not have unacceptable effect on the structural integrity of the containment, in fact, no genuine assessment has yet taken place. This issue from the Spring refueling outage 2020 was pushed to Fall 2021 and now is further deferred to Spring 2023 (OR22). At what point in time will the NRC require a valid assessment?
The characterization of a deferral of assessments is not borne out by our inspection results.
The licensee performed technical assessments in both the spring 2020 and fall 2021 refueling outages, which we then inspected and documented in NRC inspection reports. The assessment in the fall 2021 refueling outage was updated with new information collected as a result of corrective actions planned and completed by the licensee from the s pring 2020 outage.
The licensee has further plans to remove the caps of the containment leak chase liner system during the performance of the planned 15-year containment integrated leak rate test planned for
Enclosure the next refueling outage in s pring 2023. NRC inspectors continue to verify that the licensee follows the requirements described in the NRC regulations and ASME Code.
Q2b. If, as noted, the surface corrosion of the containment liner is deemed to NOT be due to water most likely leaking from the refueling cavity, then what IS causing the observed surface corrosion of the liner and on what basis did the NRC determine that corrosion did not affect the integrity of the liner?
NRC inspectors reviewed a sample of the licensees visual inspections via borescope through the leak chase channel test connections as well as the licensees documented corrosion analysis. The inspectors confirmed by inspection activities that there is water in the containment leak chase cavity system. The identified corrosion was limited to the surface of the metal and did not show any significant loss of material. The corrosion analysis supported this visual evidence and provided a reasonable basis for integrity of the metal liner. In reaching conclusions related to the adequacy of the licensees assessment of integrity of the leak chases, the inspectors considered the results of their interviews with plant staff, their independent review of plant records showing visual examination results of portions of the leak chases, and water chemistry sample results. As stated in our inspection report, the inspectors considered, in particular, the chemistry results showing high water pH which would preclude significant corrosion of the liner metal. Additionally, the inspectors noted that continued augmented monitoring by NextEra staff was an appropriate corrective action to verify their conclusions that the source of the water was from the refueling cavity.
Q3b. After the myriad of measuring and reporting failures by NextEra noted above, did the NRC staff complete their own 2021 data measurements on the CIS and compare them directly to NextEras 2021 data results?
NRC inspection activities documented in our fourth quarter 2021 NRC inspection report identified an instance where structural monitoring measurements of the Seabrook containment internal structure were not properly evaluated in accordance with the licensees structural monitoring program. During the spring 2021 refueling outage, NRC inspectors conducted independent walkdowns of the containment internal structure area of containment. As part of this walkdown the inspectors independently took photographs and measurements of multiple areas of the structure. The inspectors measurements were consistent with the licensees documented data measurements.
Q3e. Please define/quantify both a reasonable ASR expansion and the indications observed as noted above? Please provide the results of the more detailed finite element analysis conducted?
A reasonable ASR expansion refers to the NRCs assessment that NextEra assumed an appropriate amount of expansion for the listed structures based on the identified indications of ASR to conclude the structures remained capable of performing as intended. Indications observed refers to two horizontal cracks (~1/8 at their widest points) in the reactor cavity pit East keyway cavity opening, a series of small horizontal cracks (~0.01) on the East wall of the North extension area, and bowing of a floor deck grating with spalling of adjacent cover concrete of the floor slab perpendicular to the East wall of the North extension area.
2 A more detailed finite element analysis (Stage 2 building deformation analysis) is currently being completed by the licensee and its engineering contractor. The NRC will perform a detailed review of this analysis and any associated corrective actions when completed. The results of our review will be documented in a future inspection report.
Q4a. Why were NextEras October 4, 2021 general area dose rates up to 150 mrem/hr (usually 6-8 mrem/hr) two days after the plant shutdown on October 2, 2021?
A large portion of the components of both trains of the RHR system are housed within the RHR vaults. In addition to use as an e mergency core cooling system during a large break loss of coolant accident to inject water into the core, the RHR system is used during outages in the shutdown cooling mode to circulate water through the reactor coolant system and remove decay heat from the fuel. During this mode of operation, activated wear products found within the reactor coolant system circulate through the piping and valves within the RHR vaults and increase the dose rates in the general vicinity.
Q4b. What are the details for NextEras Radiation Work permit 0101 for the A and B RHR vaults that were to be performed by the individual exposed to high radiation levels on October 5, 2021?
Radiation Work Permit (RWP) 0101 is used for general management and inspector walkdowns during outages. Task 20 of the RWP, used by the individual on October 5, 2021, allows access to radiation and high radiation areas for inspector walkdowns, but cannot be used to perform physical work. The alarm setpoints associated with Task 20 were 10 mrem dose and 50 mrem/hr dose rate. The individual that is mentioned in the report was an NRC inspector performing walkdowns of the RHR system and upon exiting the area noted that they had received 4.2 mrem of dose with a maximum dose rate of 47 mrem/hr.
3
