PNP 2022-024, Request for Exemption from 10 CFR 140.11(a)(4) Concerning Primary and Secondary Liability Insurance
| ML22299A059 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 10/26/2022 |
| From: | Fleming J Holtec Decommissioning International |
| To: | Office of Nuclear Material Safety and Safeguards, Office of Nuclear Reactor Regulation, Document Control Desk |
| Shared Package | |
| ML22299A059 | List: |
| References | |
| HDI PNP 2022-024 | |
| Download: ML22299A059 (1) | |
Text
Krishna P. Singh Technology Campus, 1 Holtec Blvd., Camden, NJ 08104 Telephone (856) 797-0900 Fax (856) 797-0909 10 CFR 140.8 10 CFR 140.11(a)(4)
HDI PNP 2022-024 October 2, 2022 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Palisades Nuclear Plant Docket Nos. 50-255 and 72-007 Renewed Facility Operating License No. DPR-20
Subject:
Request for Exemption from 10 CFR 140.11(a)(4) Concerning Primary and Secondary Liability Insurance
References:
- 1. Letter from Entergy Nuclear Operations, Inc. to U.S. Nuclear Regulatory Commission, Certifications of Permanent Cessation of Power Operations and Permanent Removal of Fuel from the Reactor Vessel, (ADAMS Accession No. ML22164A067), dated June 13, 2022 2.
Holtec Decommissioning International, LLC (HDI) letter to U.S. Nuclear Regulatory Commission, Request for Exemptions from Certain Emergency Planning Requirements of 10 CFR 50.47(b); 10 CFR 50.47(c)(2); and 10 CFR Part 50, Appendix E, (ADAMS Accession No. ML22192A134), dated July 11, 2022 In accordance with Title 10 of the Code of Federal Regulations (10 CFR) Part 140, Section 140.8, "Specific exemptions," (10 CFR 140.8) Holtec Decommissioning International, LLC (HDI),
on behalf of Holtec Palisades, LLC (Holtec Palisades), requests authorization for a permanent exemption from 10 CFR 140.11, Amounts of financial protection for certain reactors, paragraph (a)(4) for Palisades Nuclear Plant (PNP). The provisions of 10 CFR 140.11(a)(4) require the licensee to have and maintain two levels of financial protection against offsite liability for each nuclear reactor which is licensed to operate, designed for the production of electrical energy, and has a rated capacity of 100,000 kilowatts electric (kWe) or more. The two levels of financial protection are as follows:
x Primary insurance coverage of $450,000,000 from private sources (referred to as "primary offsite liability insurance"); and x
Secondary financial protection in the form of private liability insurance available under an industry retrospective rating plan (referred to as "secondary financial protection").
HOLTEC DECOMM I SS ION I NG I NTFRNAT I ONAL
HDI PNP 2022-024 Page 2 of 2 HDI is requesting an exemption from 10 CFR 140.11(a)(4) for PNP to (1) reduce the required level of primary offsite liability insurance to $100,000,000 and (2) eliminate the requirement to carry secondary financial protection for PNP. The exemption request is provided in the Enclosure to this letter.
In Reference 1, Entergy certified to the NRC, in accordance with 10 CFR 50.82, Termination of license, paragraph (a)(1)(i), that power operations ceased at PNP on May 20, 2022. In addition, Entergy certified in accordance with 10 CFR 50.82 (a)(1)(ii), that the fuel was permanently removed from the PNP reactor vessel and placed in the PNP Spent Fuel Pool on June 10, 2022.
The underlying purpose of 10 CFR 140.11(a)(4) is to require sufficient liability insurance to ensure adequate funding of any claims resulting from a potential nuclear incident or precautionary evacuation associated with an individual power reactor. However, the regulation does not take into consideration the reduced potential for, and consequences of, such nuclear incidents at permanently shutdown facilities. The proposed exemption would allow a reduction in the level of offsite insurance coverage for the PNP site to a level that is commensurate with the permanently shutdown and defueled status of the PNP reactor, while still meeting the underlying purpose of 10 CFR 140.11(a)(4).
Holtec International, has performed analyses showing that approximately 12 months after the shutdown of PNP, the spent fuel stored in the Spent Fuel Pool (SFP) will have decayed sufficiently such that there is a significant reduction in risk from a theoretical SFP drain down event. This reduction in risk supports the basis for the proposed exemption from 10 CFR 140.11(a)(4) provided in the Enclosure to this letter. The analyses establishing an approximate 12-month spent fuel decay time was provided to the NRC in Reference 2.
The approximate 12-month spent fuel decay period for PNP will be reached on May 31, 2023.
Therefore, HDI requests NRC approval of this exemption request by May 31, 2023.
This letter contains no new or revised regulatory commitments.
Should you have any questions or require additional information, please contact Jim Miksa Regulatory Assurance Engineer at (269) 764-2945.
Sincerely, Jean A. Fleming Vice President of Licensing, Regulatory Affairs & PSA Holtec International
Enclosure:
Request for Exemption from 10 CFR 140.11(a)(4) cc:
NRC Region III Regional Administrator NRC Senior Resident Inspector - Palisades Nuclear Plant NRC Project Manager - Palisades Nuclear Plant Designated Michigan State Official Jean A. Fleming Digitally signed by Jean A. Fleming Date: 2022.10.26 08:47:38 -04'00'
Enclosure HDI PNP 2022-024 Request for Exemption from 10 CFR 140.11(a)(4)
Enclosure HDI PNP 2022-024 Page 1 of 18 TABLE OF CONTENTS I.
PROPOSED EXEMPTION 2
II.
BACKGROUND 2
III.
DETAILED DESCRIPTION 2
IV.
BASIS FOR EXEMPTION 3
V.
TECHNICAL EVALUATION 5
VI.
JUSTIFICATION FOR EXEMPTION...
13 VII.
PRECEDENT 13 VIII. ENVIRONMENTAL ASSESSMENT...
14 IX.
CONCLUSION 16 X.
REFERENCES 16
Enclosure HDI PNP 2022-024 Page 2 of 18 I.
PROPOSED EXEMPTION In accordance with Title 10 of the Code of Federal Regulations (10 CFR) Part 140, Section 140.8, Specific exemptions, (10 CFR 140.8) Holtec Decommissioning International, LLC (HDI),
on behalf of Holtec Palisades, LLC (Holtec Palisades), requests authorization for a permanent exemption from 10 CFR 140.11, Amounts of financial protection for certain reactors, paragraph (a)(4) for Palisades Nuclear Plant (PNP). The provisions of 10 CFR 140.11(a)(4) require the licensee to have and maintain two levels of financial protection against offsite liability for each nuclear reactor which is licensed to operate, designed for the production of electrical energy, and has a rated capacity of 100,000 kilowatts electric (kWe) or more. The two levels of financial protection are as follows:
x Primary insurance coverage of $450,000,000 from private sources (referred to as "primary offsite liability insurance"); and x
Secondary financial protection in the form of private liability insurance available under an industry retrospective rating plan (referred to as "secondary financial protection").
HDI is requesting an exemption from 10 CFR 140.11(a)(4) for PNP to (1) reduce the required level of primary offsite liability insurance to $100,000,000 and (2) eliminate the requirement to carry secondary financial protection for PNP.
II.
BACKGROUND The Palisades Nuclear Plant is a single reactor unit facility located on property owned by Holtec Palisades, LLC on the eastern shore of Lake Michigan approximately four and one-half miles south of the southern city limits of South Haven, Michigan. There are approximately 469 acres within the site boundary.
By letter dated June 13, 2022, Entergy Nuclear Operations, Inc. (Entergy) certified to the U.S.
Nuclear Regulatory Commission (NRC) that power operations ceased at PNP on May 20, 2022, and that the fuel was permanently removed from the reactor vessel and placed in the PNP spent fuel pool (SFP) on June 10, 2022, in accordance with 10 CFR 50.82, Termination of License, paragraphs (a)(1)(i) and (a)(1)(ii) (Reference 1).
Since the PNP reactor is in a permanently defueled condition, the operational focus is with the spent fuel and the SFP cooling systems. In this condition, the spectrum of credible accidents is much smaller than for an operational plant. Further, with the PNP certifications of permanent shutdown and defuel, in accordance with 10 CFR 50.82(a)(1)(i) and (ii), the 10 CFR Part 50 license for PNP no longer authorizes operation of the PNP reactor or emplacement or retention of fuel in the reactor vessel. As such, the majority of the design basis accident (DBA) scenarios previously postulated in the safety analyses for the plant are no longer possible and were removed from the Updated Final Safety Analysis Report (UFSAR) under the provisions of 10 CFR 50.59, Changes, tests and experiments.
III.
DETAILED DESCRIPTION In accordance with 10 CFR 140.8, HDI requests a permanent exemption from 10 CFR 140.11(a)(4) for PNP. The provisions of 10 CFR 140.11(a)(4) require licensees to have
Enclosure HDI PNP 2022-024 Page 3 of 18 and maintain two levels of financial protection against offsite liability for each nuclear reactor which is licensed to operate, designed for the production of electrical energy, and has a rated capacity of 100,000 kilowatt electric (kWe) or more. The two levels of financial protection are as follows:
x Primary insurance coverage of $450,000,000 from private sources (referred to as "primary offsite liability insurance"); and x
Secondary financial protection in the form of private liability insurance available under an industry retrospective rating plan (referred to as "secondary financial protection").
HDI is requesting an exemption from 10 CFR 140.11(a)(4) for PNP to (1) reduce the required level of primary offsite liability insurance to $100,000,000 and (2) eliminate the requirement to carry secondary insurance coverage for PNP.
10 CFR 140.11(a)(4) reads as follows:
"(a) Each licensee is required to have and maintain financial protection:
[]
(4) In an amount equal to the sum of $450,000,000 and the amount available as secondary financial protection (in the form of private liability insurance available under an industry retrospective rating plan providing for deferred premium charges equal to the pro rata share of the aggregate public liability claims and costs, excluding costs payment of which is not authorized by section 170o.(1)(D) of the Act, in excess of that covered by primary financial protection) for each nuclear reactor which is licensed to operate and which is designed for the production of electrical energy and has a rated capacity of 100,000 electrical kilowatts or more: Provided, however, that under such a plan for deferred premium charges for each nuclear reactor that is licensed to operate, no more than $131,056,000 with respect to any nuclear incident (plus any surcharge assessed under subsection 170o.(1)(E) of the Act) and no more than $20,496,000 per incident within one calendar year shall be charged.
Holtec International, has performed analyses showing that approximately 12 months after PNPs shutdown, the spent fuel stored in the SFP will have decayed sufficiently such that there is a significant reduction in risk from a theoretical SFP drain down event. This reduction in risk supports the basis for the proposed exemption from 10 CFR 140.11(a)(4). These analyses were provided in a previously submitted HDI letter to the NRC, Request for Exemptions from Certain Emergency Planning Requirements of 10 CFR 50.47(b);
10 CFR 50.47(c)(2); and 10 CFR Part 50, Appendix E (Reference 2).
IV.
BASIS FOR EXEMPTION The underlying purpose of 10 CFR 140.11(a)(4) is to require sufficient liability insurance to ensure adequate funding of any claims resulting from a potential nuclear incident or precautionary evacuation associated with an individual power reactor. The financial protection
Enclosure HDI PNP 2022-024 Page 4 of 18 limits of 10 CFR 140.11(a)(4) were established to require that licensees maintain sufficient insurance to cover the costs of a nuclear incident at an operating reactor site.
This regulation does not take into consideration the reduced potential for and consequences of such nuclear incidents at permanently shutdown facilities. PNP is a single unit reactor site, which has been permanently shutdown and defueled. The proposed exemption would allow a reduction in the level of offsite insurance coverage to a level that is commensurate with the permanently shutdown and defueled status of the onsite reactor, while maintaining the underlying purpose of 10 CFR 140.11(a)(4).
Although the likelihood of an accident at an operating reactor is small, the consequences can be large, in part due to the high temperatures and pressures of the reactor coolant system as well as the inventory of radionuclides. For a permanently shutdown and defueled reactor, such as PNP, nuclear accidents involving the reactor and the associated systems, structures, and components (SSCs) are no longer possible. Furthermore, reductions in the probability and consequences of non-operating reactor nuclear incidents are substantially reduced because:
- 1) the decay heat from the spent fuel decreases over time, which reduces the amount of cooling required to prevent the spent fuel from heating up to a temperature that could compromise the ability of the fuel cladding to retain fission products; and 2) the relatively short-lived radionuclides contained in the spent fuel, particularly volatile components like iodine and noble gasses, decay away, thus reducing the inventory of radioactive materials available for release.
Although the potential for, and consequences of, nuclear accidents decline substantially after a reactor is permanently defueled, they are not completely eliminated. There are potential onsite and offsite radiological consequences that could be associated with the onsite storage of the spent fuel in the SFP. In addition, a site with a permanently shutdown and defueled reactor, such as PNP, may contain an inventory of radioactive liquids, activated reactor components, and contaminated materials. For the purposes of modifying the amount of offsite insurance coverage maintained by a licensee for a permanently shutdown and defueled reactor, the potential radiological consequences of non-operating reactor nuclear incidents are appropriate to consider, despite their very low probability of occurrence.
The NRC has generically evaluated the legal, technical, and policy issues regarding the financial protection requirements for large nuclear power plants that have been permanently shutdown and recommended changes to the power reactor financial protection regulations that would allow licensees to lower offsite insurance levels to $100 million. The results of the NRC evaluations were summarized in SECY-96-256 (Reference 3) and the NRC recommended course of action was approved by the Commission in a Staff Requirements Memorandum (SRM) (Reference 4). These documents established the basis for the NRC exercising its discretionary authority to specify an appropriate level of offsite insurance coverage for permanently shutdown nuclear power reactors.
In SECY-00-145 (Reference 5) and SECY-01-0100 (Reference 6), the NRC discussed additional information concerning SFP zirconium fire risks at decommissioning reactors and associated implications for offsite property damage insurance. Analyzing when spent fuel stored in the SFP is capable of adequate air-cooling is one measure that demonstrates when the probability of a zirconium fire would be exceedingly low.
Enclosure HDI PNP 2022-024 Page 5 of 18 As discussed in the NRC response to a comment submitted by the Nuclear Energy Institute (NEI) in SECY-00-145 (see "NRC Staff Responses to NEI White Paper Comments on Improving Decommissioning Regulations," page 5, response to Comment 3):
" the staff believes that full insurance coverage must be maintained for 5 years or until a licensee can show by analysis that its spent fuel pool is no longer vulnerable to such a
[zirconium] fire."
In addition, as discussed in the NRC response to another NEI comment in SECY-00-145 (see "NRC Staff Responses to NEI White Paper Comments on Improving Decommissioning Regulations," page 6, response to Comment 4):
"Since the zirconium fire scenario would be possible for up to several years following shutdown, and since the consequences of such fire could be severe in terms of offsite health consequences, property damage, and land contamination, the staff position is that full offsite liability coverage (both primary and secondary levels) must be retained for five years or until analysis has indicated that a zirconium fire is no longer possible. At that point, primary coverage would be reduced from $200 million to $100 million and participation in the secondary retrospective rating pool would no longer be required" Note: the primary financial protection coverage specified in 10 CFR 140.11(a)(4) was increased from $200 million to $450 million (81 FR 96348) separate from the above quoted NEI comment response in SECY-00-145. The NRC's recommendation for a reduction in the required insurance coverage to $100 million and the supporting basis for the reduced coverage did not change.
V.
TECHNICAL EVALUATION By letter dated June 13, 2022, Entergy certified to the NRC that power operations ceased at PNP on May 20, 2022, and that the fuel was permanently removed from the reactor vessel and placed in the PNP spent fuel pool (SFP) on June 10, 2022 (Reference 1).
With the reactor in a permanently defueled condition, the operational focus is with the spent fuel and the spent fuel pool (SFP) cooling systems. In this condition, the spectrum of credible accidents is much smaller than for an operational plant. Further, with the PNP certifications of permanent shutdown and defuel, in accordance with 10 CFR 50.82(a)(1)(i) and (ii), the 10 CFR Part 50 license for PNP no longer authorizes operation of the PNP reactor or emplacement or retention of fuel in the reactor vessel. As such, the majority of the design basis accident (DBA) scenarios previously postulated in the safety analysis for the plant are no longer possible and were removed from the UFSAR under the provisions of 10 CFR 50.59, Changes, tests and experiments.
Accident Analysis Overview With the termination of reactor operations and permanent removal of fuel from the PNP reactor vessel, the postulated accidents involving failure or malfunction of the reactor and supporting systems, structures, and components (SSCs) are no longer applicable to the PNP facility.
The HDI submittal, Request for Exemptions from Certain Emergency Planning Requirements of
Enclosure HDI PNP 2022-024 Page 6 of 18 10 CFR 50.47(b); 10 CFR 50.47(c)(2); and 10 CFR 50, Appendix E, (Reference 2) provides information on the disposition of accidents no longer applicable and the remaining incidents of concern. The analyses of the remaining incidents are summarized in the following sections.
A. Consequences of Design Basis Accidents (DBA)
The NRC approved the PNP Permanently Defueled Technical Specifications (PDTS) on May 13, 2022, with the issuance of PNP License Amendment No. 272 (Reference 7). The license amendment included the statement that the applicable DBAs for PNP in the permanently defueled condition are: (1) the Fuel Handling Accident (FHA) in the Fuel Handling Building, (2) the Postulated Cask Drop Accident (3) the accidental release of waste gas, and (4) the accidental release of waste liquid.
(1) The Fuel Handling Accident (FHA) in the Fuel Handling Building (FHB)
An FHA may occur in the FHB during movement of a fuel assembly. The fuel assembly is moved under water and the accident is assumed to occur when the fuel assembly is damaged. The FHA analysis assumed 22.5 feet of water above the stored fuel, which resulted in an effective decontamination factor of 183.07 and an overall decontamination factor for elemental iodine of 252 (Reference 8). The FHA utilizes the Alternate Source Term (AST) methodology described in Regulatory Guide 1.183, "Alternative Radiological Source Terms for Evaluating Design Basis Accidents at Nuclear Power Reactors (Reference 9).
The analysis demonstrates that after a decay time of 60 days following permanent cessation of power operations of the PNP reactor, with no credit taken for the operability of mitigating structures, systems, or components (SSCs), that a FHA in the SFP results in a dose of 0.014 rem Total Effective Dose Equivalent (TEDE) at the exclusion area boundary (EAB), which is below the Environmental Protection Agencys (EPA) early phase Protective Action Guideline (PAG) criteria of 1 rem TEDE for recommended evacuation.
(2) The Postulated Cask Drop Accident The PNP Defueled Safety Analysis Report (DSAR) evaluates the postulated cask drop accidents. The analysis included a scenario in which a cask is dropped onto spent fuel which has decayed for 90 days. The scenario assumes the Fuel Handling Building (FHB) charcoal filter is not operating and all radiation is released unfiltered from the FHB. The accident results in a dose of 0.08 rem at the EAB which is below the EPAs early phase PAG criteria of 1 rem TEDE for recommended evacuation.
(3) The Accidental Release of Waste Gas The atmospheric dispersion coefficients and the source term for the FHA discussed above bound those of the design basis gas decay tank rupture (GDTR), and the volume control tank rupture accident is no longer applicable in the permanently defueled condition. Therefore, it can be concluded that the dose consequences of the FHA bound the dose consequences of the GDTR with the same decay period.
Enclosure HDI PNP 2022-024 Page 7 of 18 (4) The Accidental Release of Waste Liquid The accidental release of waste liquid incidents discussed in the DSAR include failure of the primary system makeup storage tank or the utility water storage tank, or an accidental discharge to the circulating water discharge canal. The primary system makeup storage tank and the utility water storage tank have administrative controls that maintain tank activity concentration such that 10 CFR Part 20, Standards for Protection Against Radiation, dose limits would not be exceeded in the event of a tank failure.
These concentration limits will be maintained in the permanently defueled condition. To prevent an accidental discharge to the circulating water discharge canal PNP has administrative controls and automatic interlocks, together with the fail-safe design of the instrumentation and control devices. These administrative and design features provide assurance against any discharge of liquid wastes that would exceed 10 CFR Part 20 limits and as such would not approach the EPA early phase PAG criteria of 1 rem TEDE after a 90-day fuel decay period.
HDI has concluded that the PNP design and administrative controls ensure that radioactive liquid leakage or spillage will be retained within the facility or within 10 CFR Part 20 dose limits.
B. Consequences of Beyond Design Basis Events (BDBE)
Spent Fuel Assembly Heat Up During a Theoretical Drain Down Event The analyses, provided in Enclosure Attachment 1 to Reference 2, compared the heat load limits for the hottest fuel assembly and for a 2X2 group of assemblies stored in the PNP SFP, to a criterion proposed in Commission Paper SECY-99-168, Improving Decommissioning Regulations for Nuclear Power Plants," (Reference 10) that is applicable to offsite emergency response for nuclear power reactors in the decommissioning process. This criterion considers the time for the hottest assembly to heat up from 30°C to 900°C adiabatically. A heat up time of 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> from tKHWLPHthe spent fuel is uncovered, was determined to be sufficient to take mitigating actions and, if necessary, offsite protective measures without offsite emergency preplanning addressing the facility.
The analysis for the PNP SFP for beyond design basis events demonstrates that approximately 12 months after shutdown, a minimum of 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> is available before the fuel cladding temperature of the hottest fuel assembly in the SFP reaches 900°C with a complete loss of SFP water inventory. As stated in NUREG-1738, Technical Study of Spent Fuel Pool Accident Risk at Decommissioning Nuclear Power Plants, (Reference 11), 900°C is an acceptable temperature to use for assessing the onset of fission product release under transient conditions (to establish the critical decay time for determining availability of 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> to evacuate) if fuel and cladding oxidation occurs in air. Based on the results of the analysis, in the unlikely event of a beyond design basis event, 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> is available to initiate appropriate mitigating actions to restore a means of heat removal to the spent fuel and, if governmental officials deem warranted, for authorities to implement offsite protective actions using a comprehensive approach to emergency planning to protect the health and safety of the public before the hottest fuel assembly reaches the rapid oxidation temperature.
Enclosure HDI PNP 2022-024 Page 8 of 18 Because of the time it would take for the adiabatic heat up to occur, there is ample time to respond to any partial drain down event that might cause such an occurrence by restoring cooling or makeup or providing spray to the PNP SFP. As a result, the likelihood that such a scenario would progress to a zirconium fire is not deemed credible.
C. Consequences of Other Analyzed Events Spent Fuel Pool Draindown Event NUREG-0586, Generic Environmental Impact Statement on Decommissioning of Nuclear Facilities, (Reference 12) Supplement 1, Section 4.3.9.2, identifies that a SFP drain down event is a beyond design basis event. The analyses provided in Reference 2 Enclosure demonstrates that, under adiabatic conditions, a significant release of radioactive material from the spent fuel is not possible within 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> from the time the spent fuel is uncovered after approximately 12 months following the permanent cessation of power operation. However, the potential exists for radiation exposure if shielding of the spent fuel in the PNP SFP is lost.
The SFP water and the concrete SFP structure serve as radiation shielding. As such, a loss of water shielding above the fuel could increase the offsite radiation levels because of the gamma rays streaming up out of the pool being scattered back to a receptor at the site boundary.
The radiological consequences of a postulated complete loss of PNP SFP water at the EAB and Control Room were analyzed. Based on the analysis, the dose rate to a receptor at the EAB and the limiting dose rate in the PNP Control Room one year after shutdown are less than 0.20 mrem/hour (hr) and 2.5 mrem/hr, respectively, which is less than the EPA PAGs (Reference 13).
Consequences of a Beyond-Design Basis Earthquake NUREG-1738 (Reference 11) identifies beyond design basis seismic events as the dominant contributor to events that could result in a loss of SFP coolant that uncovers fuel for plants in the Central and Eastern United States. Additionally, NUREG-1738 identifies a zirconium fire resulting from substantial loss-of-water inventory from the SFP, as the only postulated scenario at a decommissioning plant that could result in significant offsite radiological release. The scenarios that lead to this condition have very low frequencies of occurrence (i.e., on the order of one to tens of times in a million years) and are considered beyond design basis events because the SFP and attached systems are designed to prevent a substantial loss of coolant inventory under accident conditions. However, the consequences of such accidents could potentially lead to an offsite radiological dose in excess of the EPA PAGs (Reference 14) at the EAB.
The risk associated with zirconium cladding fire events decreases as the spent fuel ages. As the spent fuel ages, the decay time increases, the decay heat decreases, and the short-lived radionuclides decay away. As the decay time increases, the overall risk of zirconium cladding fire continues to decrease due to two factors: (1) the amount of time available for preventative actions increases, which reduces the probability that the actions would not be successful; and (2)the increased likelihood that the fuel is able to be cooled by air, which decreases the reliance
on actions to prevent a zirconium fire. The results of the research conducted for NUREG-1738
and NUREG-2161, "Consequence Study of a Beyond-Design-Basis Earthquake Affecting the
Enclosure HDI PNP 2022-024 Page 9 of 18 Spent Fuel Pool for a U.S. Mark I Boiling Water Reactor," (September 2014) (Reference 15) suggests that, while other radiological consequences can be extensive, a postulated accident scenario leading to a SFP zirconium fire, where the fuel has had significant decay time, will have little potential to cause offsite early fatalities due to dose, regardless of the type of offsite response.
The purpose of NUREG-2161 was to determine if accelerated transfer of older, colder spent fuel from the SFP at a reference plant to dry cask storage significantly reduces the risks to public health and safety. The study states that "this study's results are consistent with earlier research studies' conclusions that spent fuel pools are robust structures that are likely to withstand severe earthquakes without leaking cooling water." The study also shows that, in the event of a radiological release, public and environmental effects are generally the same or smaller than earlier studies.
In SECY-93-127, Financial Protection Required of Licensees of Large Nuclear Power Plants During Decommissioning (Reference 16), the NRC staff considered potential financial liability of a zirconium fire to determine that the overall risk at decommissioning plants does not justify the full insurance coverage once the spent fuel has sufficiently decayed. In its Staff Requirements Memorandum for SECY-93-127 (Reference 17), the Commission approved a policy that authorized reductions in commercial liability insurance coverage through the exemption process after the spent fuel had undergone an appropriate period of cooling, which the NRC staff defined as when the spent fuel could be air-cooled if the spent fuel pool was drained of water.
In NUREG/CR-6451 A Safety and Regulatory Assessment of Generic BWR and PWR Permanently Shutdown Nuclear Power Plants, (Reference 18) the representative PWR SFP was shown to be able to be air cooled. HDI has compiled data comparing the input parameters between this representative generic analysis and like data for PNP. This information is provided in Table 1 and Table 2.
Table 1 - Fuel Assembly Parameters Parameter NUREG/CR-6451 PNP Power 1130 MWe (Section 3.1.1) approx. 3330 MWt (Note 1) 2565.4 MWt (Note 2)
Assemblies 193 (Section 3.1.1) 204 MWt/Assembly 17.25 [§ 3330/193]
12.58 (calculated)
Fuel Design 17 x 17 (p. 3-5) 15 x 15 Burnup 60 GWd/MTU (Section 3.1.1) 52 GWd/MTU Decay Time approx. 17 months (Section 3.1.3) 519 days (Note 3) approx. 12 months 05/20/2022 to 5/31/2023 376 days Cladding Oxidation Temperature Limit 565°C (Section 3.1.3) 565°C
Enclosure HDI PNP 2022-024 Page 10 of 18 MTU/Fuel Assembly 0.461 (Note 4) 0.431 Operating Time 1604.5 days (Note 5) 1780.8 days (Note 5)
= (52) x (0.431) x ((204) / (2565.4) x (1000 MW / 1 GW)) (calculated)
Fuel Assembly Transverse Dimension 8.43 in. (Note 6) 8.117 in.
Rod Center-to-Center Pitch 0.496 in. (Note 7) 0.55 in.
Rod Outside Diameter 0.374 in (Note 7) 0.4155 in.
Active Fuel Height 144 in. (Note 7) 132.6 in.
Overall Fuel Rod Length 168 in. (Note 7)
(active + inactive length) 140.2 in.
Fuel Rods per Fuel Assembly 289 (Note 7)
(Fuel Rods + Non-Fuel Rods) 216 Active Volume (Note 8) 10,223.3 in3 (0.1677 m3) (Note 8) 8,736.2 in3 = (132.6 in) x (8.117 in)2 (0.1432 m3) (calculated) (Note 8)
Power Density (Note 9) 103 MWt/m3 (Note 9) 87.9 MWt/m3 (Note 9)
= ((2565.4) / (204)) / (0.1431)
(calculated)
Notes:
- 1)
The thermal power of the representative PWR in NUREG/CR-6451 is not provided; therefore, an approximate value, based on 34 percent thermal efficiency, is used.
- 2)
PNP RFOL power is 2565.4 MWt.
- 3)
The number of months were converted to days by the calculation (17 / 12) 366 days.
Since a longer decay period results in less decay heat and is more conservative for comparing to PNP with a shorter decay period.
- 4)
Refer to Table 2.2 of NUREG/CR-6441 (Reference 23).
- 5)
Operating time () is computed using the burnup (GWd/MTU), uranium mass per fuel assembly (MTU/FA), number of in the core fuel assemblies (FA), and plant thermal power (MWt).
1000 1
- 6)
The PWR example in NUREG/CR-6441 utilizes a 17 17 fuel assembly from a 193-fuel assembly core with a uranium mass of 0.461 MTU.
- 7)
Refer to Table A.3 of NUREG/CR-6441 (Reference 23).
- 8)
Active Volume = Active Fuel Height (Fuel Assembly Transverse Dimension)2
- 9)
Power Density = (MWt/Fuel Assembly) / Active Volume
Enclosure HDI PNP 2022-024 Page 11 of 18 Table 2 - Spent Fuel Rack Parameters Parameter NUREG/CR-6451 PNP (Note 1)
Design HD (Note 2)
Region 1 Region 2 M - Flux Trap C - Flux Trap B - HD Material SS (Note 2)
Region 1 Region 2 M - SS, NA (Note 3)
C - SS, NA (Note 4)
B - SS, NA (Note 5)
Pitch (Note 6) 10.40 in.
Region 1 Region 2 M - 10.25 in. x 10.25 in.
C - 10.69 in. x 11.25 in.
B - 9.17 in. x 9.17 in.
Bottom Orifice 5 in. dia.
Region 1 Region 2 M - 5.5 in. dia.
C - 5 in. dia.
B - 4 in. dia.
Opening per Cell 8.75 in. x 8.75 in.
Region 1 Region 2 M - 8.75 in. x 8.75 in.
C - 9.0 in. x 9.0 in.
B - 9.0 in. x 9.0 in.
Cell Wall Thickness 0.185 in.
Region 1 Region 2 M - 0.232 in.
C - 0.50 in.
B - 0.137 in. (Note 7)
Neutron Absorber Not Specified M - MetamicTM C - CarborundumTM B - BoraflexTM (Notes 3,4 and 5)
Downcomer Width 3 in.
1.04 in. to 5.63 in. (Note 8)
Plenum Height Under Racks 6 in.
Region 1 Region 2 M - 12.625 in.
C - 11.63 in.
B - 6.79 in.
SFP Perimeter 128 ft.
159 ft (Note 9)
Downcomer Area 29.75 ft2 (2.764 m2) 111.3 ft2 (10.337 m2) (Note 10)
Fuel Assemblies in SFP 1460 892 available locations 703 assemblies (Note 11)
Enclosure HDI PNP 2022-024 Page 12 of 18 Notes:
1)
The PNP SFP has two fuel storage rack regions with three rack types BoraflexTM (B),
CarborundumTM (C), MetamicTM (M) (Region 1 and Region 2).
2)
Abbreviations: HD = high density; SS = stainless steel 3)
MetamicTM racks have a boron carbide/aluminum neutron absorber (NA) incorporated into the fuel racks and are credited in SFP criticality analysis.
4)
CarborundumTM racks have a boron carbide neutron absorber (NA) incorporated into the fuel racks but are not credited in SFP criticality analysis.
5)
BoraflexTM racks have a BoraflexTM neutron absorber (NA) incorporated into the fuel racks but are not credited in SFP criticality analysis.
6)
Pitch = center to center distance from cell to cell 7)
Includes thickness of inner cell wall, Neutron Absorber channel and outer cell wall/sleeve 8)
Width of downcomer varies depending on local geometry and proximity of SFP racks to wall.
9)
SFP perimeter is the sum of wall lengths of both the Main Pool and the North Tilt Pit (NTP).
- 10) Includes 71.8 ft2 downcomer area from the removed 11x11 rack in cask loading area in the northeast corner of the main pool and 9.5 ft2 downcomer area from the NTP.
- 11) The number of fuel assemblies in the SFP are as of the final core offload. This number will not change until the fuel is offloaded from the SFP to dry casks, which is currently planned for 2024.
A comparison of the fuel design parameters for fuel assembly power, and power density of the 15 x 15 fuel assemblies from PNP found that they are the same or conservative when compared to those for the 17 x 17 fuel assemblies modeled in NUREG/CR-6451. It can therefore be concluded that the analytical results for the NUREG/CR 6451 model fuel assembly can be conservatively applied to the PNP fuel assemblies.
The NUREG/CR-6451 SFP storage rack design and configuration were also compared to those for the PNP SFP. Based on this comparison, it was found that the PNP fuel storage rack Region 2 cell pitch and cell bottom orifice dimensions are smaller than the values modeled in the NUREG. However, these differences are considered to be conservatively offset by the lower power density of the PNP fuel assemblies, substantially larger downcomer areas for improved buoyancy driven air flow and natural circulation, and the fewer number of fuel assemblies that are stored in the fuel racks as compared to the NUREG/CR-6451 PWR model.
A PNP analysis demonstrates that the risk of a SFP seismically induced structural failure and rapid loss of inventory is less than the generic bounding estimates provided in NUREG-1738 (1 x 10-5 per year including non-seismic events). The analyses were provided to the NRC in Reference 2, Enclosure Attachment 4.
Conclusion The Holtec Spent Fuel Pool Heat Up Calculations submitted to the NRC in Reference 2 for PNP demonstrates that a minimum of 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> is available before the fuel cladding temperature of the hottest fuel assembly in the SFP reaches the zirconium fire temperature of 900 degrees Celsius (°C) with a beyond design basis complete loss of SFP water inventory. In addition, the PNP spent fuel and SFP conditions were determined to be bounded by the NUREG/CR-6451 benchmark. Thus demonstrating that spent fuel would be air coolable at approximately
Enclosure HDI PNP 2022-024 Page 13 of 18 12 months after permanent shutdown. Regarding the dose consequences, as described above, the dose for the remaining DBA and BDBE would be below the regulatory requirements.
VI.
JUSTIFICATION FOR EXEMPTION AND SPECIAL CIRCUMSTANCES As stated in 10 CFR 140.8, the Commission may, upon application by any interested person or upon its own initiative, grant such exemptions from the requirements of the regulations in this part as it determines are authorized by law and are otherwise in the public interest.
As discussed below, this exemption request satisfies the provisions of 10 CFR 140.8.
A.
The exemption is authorized by law The proposed exemption is consistent with the requirements of the Atomic Energy Act of 1954, as amended (Price-Anderson Act), which requires that power reactor licensees maintain some level of public liability financial protection. The NRC has granted exemptions to other licensees for insurance reductions of the same regulation being requested here by HDI and have been previously determined to be authorized by law and granted (see Section VII of this Enclosure).
In addition, as discussed in an NRC letter to Dominion Nuclear Connecticut, Inc.
(Reference 19), post-shutdown insurance requirements for nuclear power plants undergoing decommissioning were addressed in a letter from the NRC Executive Director for Operations to the Chairman of the Advisory Committee on Reactor Safeguards (ACRS), dated September 17, 2001. The NRC staff and the ACRS agreed that onsite and offsite insurance coverage can be substantially reduced shortly after a facility permanently shuts down. The ACRS also accepted the NRC staff's assessment that the primary offsite liability can be reduced to $100 million and that decommissioning licensees can be released from participation in the secondary insurance pool. Therefore, the exemptions are authorized by law B.
The exemption is otherwise in the public interest Approval of the exemption request would result in more efficient use of funds in the HDI decommissioning trust funds. The reduction in offsite protection for PNP from $450 million to $100 million and elimination of the requirement to participate in the secondary insurance pool would continue to require a level of financial protection commensurate with the underlying purpose of 10 CFR 140.11(a)(4) while eliminating an unnecessary financial burden. Therefore, the proposed exemption is otherwise in the public interest.
VII.
PRECEDENT The exemption request for 10 CFR 140.11(a)(4) is consistent with exemption requests that recently have been issued by the NRC for other nuclear power reactor facilities beginning decommissioning. Specifically, the NRC granted similar exemptions to Holtec Decommissioning International, LLC, for Pilgrim Nuclear Power Station (Reference 20); Exelon Generation Company, LLC, for Three Mile Island Nuclear Station (Reference 21); and Florida Power & Light for NextEra Energy Duane Arnold (Reference 22).
Enclosure HDI PNP 2022-024 Page 14 of 18 Similar to the current request, these precedents each resulted in exemptions from the requirements in 10 CFR 140.11(a)(4). For the same reasons that the NRC recently issued these exemptions, HDI seeks approval of the exemptions proposed in this exemption request.
VIII. ENVIRONMENTAL ASSESSMENT The proposed exemption meets the eligibility criterion of categorical exclusion set forth in 10 CFR 51.22(c)(25) because the proposed exemption involves: (i) no significant hazards consideration; (ii) no significant change in the types or significant increase in the amounts of any effluents that may be released offsite; (iii) no significant increase in individual or cumulative public or occupational radiation exposure; (iv) no significant construction impact; (v) no significant increase in the potential for or consequences from radiological accidents; and (vi) the requirements from which the exemption is sought involve surety, insurance, or indemnity requirements. Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed exemption.
L
No Significant Hazards Consideration Determination HDI has evaluated the proposed exemption from 10 CFR 140.11(a)(4) for PNP to
determine whether or not a significant hazards consideration is involved by focusing
on the three standards set forth in 10 CFR 50.92 as discussed below:
Does the proposed exemption involve a significant increase in the probability or
consequences of an accident previously evaluated?
The proposed exemption has no effect on structures, systems, and components
(SSCs) and is unrelated to the capability of any plant SSC to perform its design
function. The proposed exemption would not increase the likelihood of the
malfunction of any plant SSC.
When the exemption becomes effective, there will be no credible events that
would result in doses to the public beyond the exclusion area boundary (EAB)
that would exceed the Environmental Protection Agency (EPA) Protective Action
Guidelines (PAGs). The probability of occurrence of previously evaluated
accidents is not increased, since most previously analyzed accidents will no
longer be possible and the probability and consequences of the remaining design
basis accidents (DBAs) are not adversely affected by the proposed exemption.
Therefore, the proposed exemption does not involve a significant increase in the
probability or consequences of an accident previously evaluated.
Does the proposed exemption create the possibility of a new or different kind of
accident from any accident previously evaluated?
The proposed exemption does not involve a physical alteration of the PNP plant.
No new or different type of equipment will be installed and there are no physical
modifications to existing equipment associated with the proposed exemption.
Similarly, the proposed exemption will not physically change any SSCs involved
in the mitigation of any accidents. Thus, no new initiators or precursors of a new
Enclosure HDI PNP 2022-024 Page 15 of 18 or different kind of accident are created. Furthermore, the proposed exemption does not create the possibility of a new accident as a result of new failure modes associated with any equipment or personnel failures. No changes are being made to parameters within which the plants are normally operated, or in setpoints which initiate protective or mitigative actions, and no new failure modes are being introduced.
Therefore, the proposed exemption does not create the possibility of a new or different kind of accident from any accident previously evaluated.
3.
Does the proposed exemption involve a significant reduction in a margin of safety?
The proposed exemption does not alter the design basis or any safety limits for the PNP plant. The proposed exemption does not impact facility operation or any plant SSC that is relied upon for accident mitigation.
Therefore, the proposed exemption does not involve a significant reduction in a margin of safety.
Based on the above, HDI concludes that the proposed exemption presents no significant hazards consideration, and, accordingly, a finding of "no significant hazards consideration" is justified.
(ii)
There is no significant change in the types or significant increase in the amounts of any effluents that may be released offsite.
There are no expected changes in the types, characteristics, or quantities of effluents discharged to the environment associated with the proposed exemption. There are no materials or chemicals introduced into the PNP plant that could affect the characteristics of types of effluents released offsite. In addition, the method of operation of waste processing systems will not be affected by the exemption. The proposed exemption will not result in changes to the design basis requirements of SSCs that function to limit or monitor the release of effluents. All the SSCs associated with limiting the release of effluents will continue to be able to perform their functions. Therefore, the proposed exemption will result in no significant change to the types or significant increase in the amounts of any effluents that may be released offsite.
(iii)
There is no significant increase in individual or cumulative public or occupational radiation exposure.
The proposed exemption does not involve any physical alterations to the configuration of the plants or any changes to operation of the facility that could lead to a significant increase in individual or cumulative occupational radiation exposure to either the workforce or the public.
Enclosure HDI PNP 2022-024 Page 16 of 18 (iv) There is no significant construction impact.
No construction activities are associated with the proposed exemption.
(v)
There is no significant increase in the potential for or consequences from radiological accidents.
See the no significant hazards considerations discussion in Item (i)(1) above.
(vi) The requirements from which exemption is sought involve surety, insurance or indemnity requirements.
The requirements from which the exemption is sought involve financial protection and for the indemnification and limitation of liability in accordance with Section 170 of the Atomic Energy Action of 1954, as amended, and 10 CFR 140.11(a)(4).
IX.
CONCLUSION In accordance with 10 CFR 140.8, HDI is requesting a permanent exemption from 10 CFR 140.11(a)(4) for the PNP site. Based on the considerations discussed above, the requested exemption is authorized by law and is otherwise in the public interest.
X.
REFERENCES
- 1. Letter from Entergy Nuclear Operations, Inc. to U.S. Nuclear Regulatory Commission, Certifications of Permanent Cessation of Power Operations and Permanent Removal of Fuel from the Reactor Vessel, (ADAMS Accession No. ML22164A067), dated June 13, 2022
- 2. Holtec Decommissioning International, LLC (HDI) letter to U.S. Nuclear Regulatory Commission, Request for Exemptions from Certain emergency Planning Requirements of 10 CFR 50.47(b); 10 CFR 50.47(c)(2); and 10 CFR Part 50, Appendix E, (ADAMS Accession No. ML22192A134), dated July 11, 2022
- 3. U.S. NRC Commission Paper, SECY-96-256, Changes to the Financial Protection Requirements for Permanently Shutdown Nuclear Power Reactors, 10 CFR 50.54(w) and 10 CFR 140.11, (ADAMS Accession No. ML15062A483), dated December 17, 1996
- 4. Staff Requirements Memorandum, "Re: SECY-96-256, Changes to Financial Protection Requirements for Permanently Shutdown Nuclear Power Reactors, (ADAMS Accession No. ML15062A454), dated January 28, 1997
- 5. U.S. NRC Commission Paper, SECY-00-145, Integrated Rulemaking Plan for Nuclear Power Plant Decommissioning, (ADAMS Accession No. ML003721626), dated June 28, 2000
Enclosure HDI PNP 2022-024 Page 17 of 18
- 6. U.S. NRC Commission Paper, SECY-01-0100, Policy Issues Related to Safeguards, Insurance, and Emergency Preparedness Regulations at Decommissioning Nuclear Power Plants Storing Fuel in Spent Fuel Pools, (ADAMS Accession No. ML011450420), dated June 4, 2001
- 7. U.S. Nuclear Regulatory Commission letter to Entergy Nuclear Operations, Inc.,
Palisades Nuclear Plant - Issuance of Amendment No. 272 Re: Permanently Defueled Technical Specifications (EPID L-2021-LLA-0099), (ADAMS Accession No. ML22039A198), dated May 13, 2022
- 8. Entergy Nuclear Operations, Inc. letter to U.S. Nuclear Regulatory Commission, License Amendment Request to Revise Renewed Facility Operating License and Technical Specifications for Permanently Defueled Condition, (ADAMS Accession Package No. ML21152A108), dated June 1, 2021
- 9. NRC Regulatory Guide 1.183, Alternative Radiological Source Terms for Evaluating Design Basis Accidents at Nuclear Power Reactors, (ADAMS Accession No. ML003716792), dated July 31, 2000
- 10. U.S. NRC Commission Paper, SECY-99-168, Improving Decommissioning Regulations for Nuclear Power Plants, (ADAMS Accession No. ML992800087), dated June 30, 1999
- 11. U.S. NRC NUREG-1738, Technical Study of Spent Fuel Pool Accident Risk at Decommissioning Nuclear Power Plants, (ADAMS Accession No. ML010430066),
dated February 2001
- 12. U.S. NRC NUREG-0586, Generic Environmental Impact Statement on Decommissioning of Nuclear Facilities, (ADAMS Accession Package Nos.
ML023470327 and ML023500228), dated November 2002
- 13. EC-92900, Clarify Applicability of EA-EC72870-01 to May 2022 Shutdown
- 14. U.S. Environmental Protection Agency, Protective Action Guides and Planning Guidance for Radiological Incidents, EPA-400/R-17-001, (EPA PAG Manual), (ADAMS Accession No. ML17044A073), dated January 2017
- 15. U.S. NRC NUREG-2161, Consequence Study of a Beyond-Design-Basis Earthquake Affecting the Spent Fuel Pool for a U.S. Mark I Boiling Water Reactor, (ADAMS Accession No. 14255A365), dated September 2014
- 16. SECY-93-127, Financial Protection Required of Licensees of Large Nuclear Power Plants During Decommissioning, (ADAMS Accession No. ML12257A628), dated May 10, 1993
- 17. Staff Requirements Memorandum, SECY-93-127 - Financial Protection Required of Licensees of Large Nuclear Power Plants During Decommissioning, (ADAMS Accession No. ML003760936), dated July 13, 1993
Enclosure HDI PNP 2022-024 Page 18 of 18
- 18. U.S. NRC NUREG/CR-6451, A Safety and Regulatory Assessment of Generic BWR and PWR Permanently Shutdown Nuclear Power Plants, (ADAMS Accession No. ML082260098), dated August 1997
- 19. Letter from U.S. NRC to Dominion Nuclear Connecticut, Inc., Millstone Power Station, Unit 1 - Exemption from Certain Requirements of 10 CFR Part 140, (ADAMS Accession No. ML040890981), dated March 30, 2004
- 20. Letter from NRC to Holtec Decommissioning International, LLC, Pilgrim Nuclear Power Station - Exemption from the Requirements of 10 CFR 140.11(a)(4)
Concerning Offsite Primary and Secondary Liability Insurance and Amendment No. 14 to Indemnity Agreement No. B-48 (EPID L-2019-LLE-0005), (ADAMS Accession No. ML19282A192), dated January 6, 2020
- 21. Letter from NRC to Exelon Generation Company, LLC, Three Mile Island Nuclear Station, Units 1 and 2 - Approval of Exemptions from the Requirements of 10 CFR 140.11(a)(4) Concerning Offsite Primary and Secondary Liability Insurance (EPID L-2020-LLE-0002), (ADAMS Accession No. ML21040A269), dated March 9, 2021
- 22. Letter from U.S. NRC to Florida Power & Light Company, Duane Arnold Energy Center
- Exemption from the Requirements of 10 CFR 140.11(a)(4) Concerning Offsite Primary and Secondary Liability Insurance and Amendment No. 15 To Indemnity Agreement No. B-68 (EPID L-2020-LLE-0115), (ADAMS Accession Nos ML21070A092 and ML21070A093), dated May 11, 2021
- 23. U.S. NRC NUREG/CR-6441 (BNL-NUREG-52494), "Analysis of Spent Fuel Heatup Following Loss of Water in a Spent Fuel Pool," (ADAMS Accession No. ML021050336), dated March 2002