RS-25-027, Drensden Nuclear Power Station, Units 2 & 3 and Quad Citiies Nuclear Power Station, Units 1 & 2 - Request Exemptions from 10 CFR 50.55a(a)(3)(iii), Which Incorporates by Reference Regulatory Guide 1.147, Revision 21, for Code Case N-921, a
| ML25045A177 | |
| Person / Time | |
|---|---|
| Site: | Dresden, Quad Cities  |
| Issue date: | 02/14/2025 |
| From: | Knowles J Constellation Energy Generation |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| RS-25-027 | |
| Download: ML25045A177 (1) | |
Text
200 Energy Way Kennett Square, PA 19348 www.ConstellationEnergy.com 10 CFR 50.12 RS-25-027 February 14, 2025 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 Dresden Nuclear Power Station, Units 2 and 3 Renewed Facility Operating License Nos. DPR-19 and DPR-25 NRC Docket Nos. 50-237 and 50-249 Quad Cities Nuclear Power Station, Units 1 and 2 Renewed Facility Operating License No. DPR-29 and DPR-30 NRC Docket Nos. 50-254 and 50-265
Subject:
Request for Exemptions from 10 CFR 50.55a(a)(3)(ii), which incorporates by reference Regulatory Guide 1.147, Revision 21, for Code Case N-921, and 10 CFR 50.55a(y)
In accordance with 10 CFR 50.12, Specific exemptions, Constellation Energy Generation, LLC (CEG), is requesting U.S. Nuclear Regulatory Commission (NRC) approval of exemptions from 10 CFR 50.55a(a)(3)(ii), which incorporates by reference Regulatory Guide 1.147, Revision 21, Table 2, including a condition that limits the use of the American Society of Mechanical Engineers (ASME) Code Case N-921 to the beginning of the Inservice Inspection (ISI) interval. CEGs exemption request also extends to the definition of Inservice Inspection Interval of 10 CFR 50.55a(y). These exemptions are being submitted at the recommendation of the NRC, as documented in the Final Rule noticed in the Federal Register adopting Code Case N-921. CEG requests exemptions for Dresden Nuclear Power Station Units 2 and 3 and Quad Cities Nuclear Power Station Units 1 and 2, because Code Case N-921 was not applied at the beginning of the current ISI interval that started prior to issuance of Regulatory Guide 1.147, Rev 21. Exemptions are requested for the remainder of each plants extended ISI interval. The details of the 10 CFR 50.12 request are attached.
CEG requests your review and approval of this request by August 30, 2025.
There are no regulatory commitments contained in this letter.
Request for Exemptions from 10 CFR 50.55a(a)(3)(ii), which incorporates by reference Regulatory Guide 1.147, Revision 21, for Code Case N-921, and 10 CFR 50.55a(y)
February 14, 2025 Page 2 If you have any questions concerning this letter, please contact Jesse Brown at 267-533-6355 Respectfully, Justin Knowles Sr. Manager - Licensing Constellation Energy Generation, LLC Attachments: 1) Request for Exemptions from Regulatory Guide 1.147, Revision 21, Condition (2) for Code Case N-921
- 2) Dresden Unit 2 & 3 - Assessment of Previously Approved Alternatives
- 3) Quad Cities Unit 1 & 2 - Assessment of Previously Approved Alternatives cc:
Regional Administrator - NRC Region III NRC Senior Resident Inspector - Dresden Nuclear Power Station NRC Senior Resident Inspector - Quad Cities Nuclear Power Station NRC Project Manager - Dresden Nuclear Power Station NRC Project Manager - Quad Cities Nuclear Power Station Illinois Emergency Management Agency - Division of Nuclear Safety
Request for Exemptions from 10 CFR 50.55a(a)(3)(ii), which incorporates by reference Regulatory Guide 1.147, Revision 21, for Code Case N-921, and 10 CFR 50.55a(y)
February 14, 2025 Page 3 bcc:
Site Vice President, Dresden Nuclear Power Station Site Vice President, Quad Cities Nuclear Power Station Regulatory Assurance Manager, Dresden Nuclear Power Station Regulatory Assurance Manager, Quad Cities Nuclear Power Station Licensing Manager - KSA/CAN Licensing Records - KSA
ATTACHMENT 1 Dresden Nuclear Power Station, Units 2 and 3 Quad Cities Nuclear Power Station, Units 1 and 2 Request for Exemptions from 10 CFR 50.55a(a)(3)(ii), incorporating by reference Regulatory Guide 1.147, Revision 21, Condition (2) for Code Case N-921, and 10 CFR 50.55a(y)
Request for Exemptions from Regulatory Guide 1.147, Revision 21, Condition (2) for Code Case N-921 Page 1 of 11 I.
Description In accordance with 10 CFR 50.12, Specific exemptions, Constellation Energy Generation, LLC (CEG), is requesting NRC approval of exemptions from 10 CFR 50.55a(y) and 10 CFR 50.55a(a)(3)(ii), which incorporates by reference Code Case N-921 from Regulatory Guide 1.147, Revision 21. The exemption request, if granted, would allow Dresden Nuclear Power Station (Dresden) Units 2 and 3 and Quad Cities Nuclear Power Station (Quad Cities) Units 1 and 2 to implement American Society of Mechanical Engineers (ASME) Code Case N-921 during the current Inservice Inspection (ISI) interval.
10 CFR 50.55a(y) defines the ISI interval as 10 years by reference to IWA-2431.
Regulatory Guide 1.147, Revision 21, Table 2 condition (2) limits initial implementation of ASME Code Case N-921 to the beginning of an ISI interval. 10 CFR 50.55a(a)(3)(ii) approves NRC Regulatory Guide 1.147, Revision 21, Inservice Inspection Code Case Acceptability, ASME Section XI, Division 1, issued March 2024, to be incorporated by reference into the regulation. Exemptions are requested for Dresden and Quad Cities because Code Case N-921 was not applied at the beginning of the current ISI interval.
Exemptions are requested for the remainder of each plants extended ISI interval. The proposed exemption request does not impact the Inservice Testing (IST) or snubber programs which are implemented as part of the ASME Operation and Maintenance Code.
The technical justification supporting implementing Code Case N-921 following the start of the ISI interval is provided in the following sections.
II.
Background.
On July 17, 2024, the NRC issued a final rule that included new approved code cases and update frequencies. (Reference 1) Amongst the modifications in the Final Rule were revisions to 10 CFR 50.55a(a)(3)(ii), which approves NRC Regulatory Guide 1.147, Revision 21, Inservice Inspection Code Case Acceptability, ASME Section XI, Division 1, issued March 2024 to be incorporated by reference into the regulation. Regulatory Guide 1.147, Revision 21, conditionally approved Code Case N-921. Code Case N-921 establishes a 12-year ISI interval for Inservice Inspection programs. The marginal extension from a 10-year to 12-year interval supports a minimum of two refueling outages per period and allows levelized distribution of examinations and tests across all inspection periods.
Code Case N-921 was approved subject to the following conditions:
(1) The licensees code of record for the ISI program must be the 2017 Edition of Section XI or later, in order to apply this code case.
(2) This code case can only be implemented at the beginning of an ISI interval as part of a routine update of the ISI program.
Request for Exemptions from Regulatory Guide 1.147, Revision 21, Condition (2) for Code Case N-921 Page 2 of 11 (3) This code case cannot be used to modify the examination schedules for augmented inspections under 10 CFR 50.55a(g)(6)(ii).
(4) The exceptions of IWB-2411(a), IWC-2411(a), and IWD-2411(a) also apply to Table 1 of this code case.
Condition (2) on N-921 was added to NRC Regulatory Guide 1.147, Revision 21 in response to an anonymous public comment (ML23235A158). The specific comment that led to the inclusion of Condition (2) is provided below for reference (ML23291A328).
B-6 Code Case N-921 Implementation Comment Summary B-6: A commenter suggested that the NRC add a condition to require implementation of Code Case N-921 at the beginning of an ISI interval. The commenter stated that implementing the code case mid-ISI interval could lead to extra burden for the NRC and the industry. Specifically, existing alternatives would likely need to be reauthorized by the NRC. The commenter suggested that the NRC should add a condition requiring that Code Case N-921 only be implemented at the start of a new interval, to eliminate these requests. The commenter stated that NRCs regulatory analysis did not provide or address the additional costs associated with updating to the code cases mid-interval for licensees submitting new alternative requests.
(13-2, 13-3)
NRC Response:
The NRC agrees with the commenter and has added a condition to only allow implementation of Code Case N-921 to occur at the beginning of an ISI interval, rather than allowing implementation during a mid-ISI interval. The NRC agrees that mid-ISI interval implementation of Code Case N-921 would create a significant burden for both the NRC and licensees because of the ongoing schedule for ISI activities and the need to resubmit requests for alternatives authorized based on a 10-year ISI interval. The NRC notes that the ASME BPV Code currently allows a 1-year extension of the 10-year ISI interval with certain conditions, which makes the necessary burden to achieve an extra 1-year ISI interval extension to be of questionable resource value. Licensees wishing to implement Code Case N-921 during a mid-ISI interval should submit an exemption request in accordance with 10 CFR 50.12, Specific exemptions, and should review all NRC-authorized alternative requests to determine whether they need to be resubmitted to the NRC for review and authorization.
As a result of this comment, the NRC added a condition to RG 1.147, Revision 21, to only allow implementation of Code Case N-921 at the beginning of a new ISI interval.
The NRC Final Rule noticed in the Federal Register reiterated the rational underlying N-921 Condition 2 (Reference 1):
There are complications associated with extending the ISI interval mid-interval. For instance, licensees wanting to extend the ISI interval mid-interval would need to evaluate all NRC-approved alternatives to determine if they should be resubmitted, especially considering that NRC may have granted the alternative assuming a 10-year ISI interval. Further, Code Case N-921 specifies requirements in terms of three 4-year periods, so licensees would need to reconcile their inspection schedules accordingly. Therefore, this final rule specifies that Code Case N-921 can only be
Request for Exemptions from Regulatory Guide 1.147, Revision 21, Condition (2) for Code Case N-921 Page 3 of 11 implemented following a routine update of the ISI program (i.e., cannot be implemented mid-interval) and requires the licensees ISI code of record to be the 2017 Edition, or later, of the BPV Code.
In summary, the NRC identified two distinct concerns with allowing mid-cycle implementation of Code Case N-921:
licensees would need to evaluate all NRC-approved alternatives to determine if they should be resubmitted, and licensees would need to reconcile their inspection schedules to conform with the three 4-year periods specified in Code Case N-921.
Additionally, 10 CFR 50.55a(y) was also revised, adding a definition of Inservice Inspection Interval to state the inspection interval described in Article IWA-2432 of ASME BPV Code,Section XI, 1989 Edition with 1991 Addenda through the 2008 Addenda, or Article IWA-2431 of ASME BPV Code,Section XI, 2009 Addenda and later. This definition creates an inconsistency with application of Code Case N-921.
Dresden and Quad Cities current ISI intervals started in January 2023 and April 2023, respectively, prior to the incorporation of Regulatory Guide 1.147, Revision 21 into the regulation. CEG had intended to utilize Code Case N-921 when incorporated and took specific actions during the interval updates to facilitate use of the case. The addition of Condition 2 after the public comment period prevented CEG from obtaining the planned benefit of Code Case N-921.
Implementation of Code Case N-921 will allow Dresden and Quad Cities to gain the benefits of the Code Case without any significant burden on the NRC or CEG. During the most recent ISI interval update for each of the units listed in Table 1, CEG proactively acted based on the information publicly available, in anticipated implementation of Code Case N-921 in the new interval. This includes revision of the period start and end dates to accommodate outage schedules and adjusting examination schedules accordingly while maintaining compliance with periodic distribution requirements. For this reason, exemption is requested from Condition 2, thus allowing the plants listed in Table 1 to implement Code Case N-921. All other conditions associated with Code Case N-921 as specified in Regulatory Guide 1.147, Revision 21, Table 2 remain applicable.
Table 1 Notes:
- 1. ISI - Inservice Inspection; CISI - Containment Inservice Inspection
- 2. The Interval End Date is subject to change in accordance with -2430(c)(1) of Code Case N-921.
Plant/Unit(s)
Interval1 ASME Section XI Code Edition Current Interval Start Date Current Interval End Date Proposed 12-yr Interval End Date2 Dresden Nuclear Power Station, Units 2 & 3 Sixth - ISI Fourth - CISI 2017 Edition January 20, 2023 January 19, 2033 January 19, 2035 Quad Cities Nuclear Power Station, Units 1 and 2 Sixth - ISI Fourth - CISI 2017 Edition April 2, 2023 April 1, 2033 April 1, 2035
Request for Exemptions from Regulatory Guide 1.147, Revision 21, Condition (2) for Code Case N-921 Page 4 of 11 III.
Basis for Approval of Exemption Request In accordance with 10 CFR 50.12, the Commission may, upon application by any interested person or upon its own initiative, grant exemptions from the requirements of 10 CFR Part 50 which are authorized by law, will not present an undue risk to the public health and safety, and are consistent with the common defense and security. The Commission will not consider granting an exemption unless special circumstances are present.
As discussed below, this exemption request satisfies the provisions of 10 CFR 50.12.
a) Authorized by law These exemptions would allow CEG to implement ASME Code Case N-921 at Dresden and Quad Cities during current ISI intervals. The NRC acknowledged the appropriateness of submitting an exemption in its response to public comments noted above. Granting the proposed exemptions will not result in a violation of the Atomic Energy Act of 1954, as amended, and will not present an undue risk to the public health and safety and is consistent with the common defense and security. Therefore, the exemptions are authorized by law.
b) Will not present an undue risk to public health and safety The underlying purpose of condition (2) on Code Case N-921 was to prevent extra burden to the NRC and the Licensee regarding ISI program implementation, examination schedule revisions and re-submittal of previously approved Relief Requests. Any potential burden associated with implementing Code Case N-921 impacts time and resources for managing the ISI program and does not impact public health and safety. Therefore, these exemptions will not present an undue risk to public health and safety.
c) Consistent with the common defense and security The proposed exemptions would allow CEG to implement ASME Code Case N-921 at Dresden and Quad Cities during the current ISI intervals and has no relation to security.
The proposed exemptions will not adversely affect CEGs ability to physically secure the sites and facilities and to protect special nuclear material. Therefore, the common defense and security is not affected by these exemptions.
d) Special circumstances are present In accordance with 10 CFR 50.12(a)(2), the NRC will not consider granting an exemption to its regulations unless special circumstances are present.
Request for Exemptions from Regulatory Guide 1.147, Revision 21, Condition (2) for Code Case N-921 Page 5 of 11 (ii) Application of the regulation in the particular circumstances would not serve the underlying purpose of the rule or is not necessary to achieve the underlying purpose of the rule.
Generally speaking, the purpose of the 2024 rulemaking adopting the current provisions of 10 CFR 50.55a(a)(3)(ii) is for the NRC to identify new, revised, and reaffirmed ASME code cases that the NRC has determined are acceptable for use as voluntary alternatives to compliance with certain provisions of the ASME BPV Code currently incorporated by reference into the NRCs regulations. Specifically with respect to Section 50.55a(a)(3)(ii), the purpose was to incorporate by reference Regulatory Guide 1.147, Revision 21, which in turn conditionally approves Code Case N-921. The NRC Final Rule noticed in the Federal Register adopting 10 CFR 50.55a(a)(3)(ii) states that [t]he inservice inspection interval and the code of record update interval should be synchronized to promote order and predictability in licensee inservice inspection programs. (Reference 1)
As stated above, the NRCs conditional approval of Code Case N-921 includes a condition that This code case can only be implemented at the beginning of an ISI interval as part of a routine update of the ISI program with the NRC explaining that that mid-ISI interval implementation of Code Case N-921 would create a significant burden for both the NRC and licensees because of the ongoing schedule for ISI activities and the need to resubmit requests for alternatives authorized based on a 10-year ISI interval.
Implementation of Code Case N-921 following the start of the current ISI interval does not inhibit the ability of CEG to comply with code required periodic distribution requirements and allows for a more efficient distribution of examinations and tests throughout the remainder of the extended interval. Currently ASME Section XI divides the 10-year ISI interval into (3) periods, with allowable adjustments described in IWA-2430. Code Case N-921 allows plants to establish consistent four-year periods over the course of a 12-year ISI interval. This will ensure that each inspection period during the 12-year interval will have at least two refueling outages. During the most recent ISI interval update for each of the plants listed in Table 1, CEG established the periods as a 4-4-2 year breakdown so the additional 2 years allowed by N-921 could be added to the third period. The specific period dates and proposed interval dates, with outages, are shown for each Unit in Tables 2 through 5 below
Request for Exemptions from Regulatory Guide 1.147, Revision 21, Condition (2) for Code Case N-921 Page 6 of 11 Table 2: Dresden Unit 2 - Sixth ISI Interval, Fourth CISI Interval Interval Periods Outages Start Date to End Date Start Date to End Date Outage Numbers 6th ISI Interval 4th CISI Interval 1/20/2023 to 1/19/2033 (current) 1/19/2035 (proposed)*
1st 1/20/2023 to 1/19/2027 D2R28 11/2023 D2R29 11/2025 2nd 1/20/2027 to 1/19/2031 D2R30 11/2027 D2R31 11/2029 3rd 1/20/2031 to 1/19/2033 (current) 1/19/2035 (proposed)*
D2R32 11/2031 D2R33**
11/2033 Table 3: Dresden Unit 3 - Sixth ISI Interval, Fourth CISI Interval Interval Periods Outages Start Date to End Date Start Date to End Date Outage Numbers 6th ISI Interval 4th CISI Interval 1/20/2023 to 1/19/2033 (current) 1/19/2035 (proposed)*
1st 1/20/2023 to 1/19/2027 D3R28 11/2024 D3R29 11/2026 2nd 1/20/2027 to 1/19/2031 D3R30 11/2028 D3R31 11/2030 3rd 1/20/2031 to 1/19/2033 (current) 1/19/2035 (proposed)*
D3R32 11/2032 D3R33**
11/2034 Notes:
- Proposed ISI interval end date for implementation of a 12-yr interval via N-921.
- Proposed last outage for implementation of a 12-yr interval via N-921.
Request for Exemptions from Regulatory Guide 1.147, Revision 21, Condition (2) for Code Case N-921 Page 7 of 11 Table 4: Quad Cities Unit 1 - Sixth ISI Interval, Fourth CISI Interval Interval Periods Outages Start Date to End Date Start Date to End Date Outage Numbers 6th ISI Interval 4th CISI Interval 4/2/2023 to 4/1/2033 (current) 4/1/2035 (proposed)*
1st 4/2/2023 to 4/1/2027 Q1R28 3/2025 Q1R29 3/2027 2nd 4/2/2027 to 4/1/2031 Q1R30 3/2029 Q1R31 3/2031 3rd 4/2/2031 to 4/1/2033 (current) 4/1/2035 (proposed)*
Q1R32 3/2033 Q1R33**
3/2035 Table 5: Quad Cities Unit 2 - Sixth ISI Interval, Fourth CISI Interval Interval Periods Outages Start Date to End Date Start Date to End Date Outage Numbers 6th ISI Interval 4th CISI Interval 4/2/2023 to 4/1/2033 (current) 4/1/2035 (proposed)*
1st 4/2/2023 to 4/1/2027 Q2R27 3/2024 Q2R28 3/2026 2nd 4/2/2027 to 4/1/2031 Q2R29 3/2028 Q2R30 3/2030 3rd 4/2/2031 to 4/1/2033 (current) 4/1/2035 (proposed)*
Q2R31 3/2032 Q2R32**
3/2034 Notes:
- Proposed ISI interval end date for implementation of a 12-yr interval via N-921.
- Proposed last outage for implementation of a 12-yr interval via N-921.
Request for Exemptions from Regulatory Guide 1.147, Revision 21, Condition (2) for Code Case N-921 Page 8 of 11 As outlined above, the NRC expressed concerns that allowing mid-cycle implementation of Code Case N-921 would result in a significant burden and identified two specific concerns underlying this assertion:
licensees would need to evaluate all NRC-approved alternatives to determine if they should be resubmitted, and licensees would need to reconcile their inspection schedules to conform with the three 4-year periods specified in Code Case N-921.
With respect to the need to evaluate previously approved alternates that were based on a 10-year ISI interval, this would not be a significant burden and in fact Constellation has already performed this evaluation. CEG performed a review of all previously authorized alternatives (relief requests) for Dresden and Quad Cities and assessed the impact of extending the interval by 2 years to implement Code Case N-921 on the technical basis supporting each alternative. The results of this assessment determined that there is no impact to the technical basis supporting any of the previously approved alternatives. The full assessment of each previously approved alternative and impact of transitioning to a 12-year interval on the supporting technical basis is included in Attachments 2 and 3 of this exemption request.
The proposed exemptions will allow implementation of Code Case N-921 for the remainder of the current ISI interval for the plants listed in Table 1. All other conditions associated with Code Case N-921 apply as specified in Regulatory Guide 1.147, Revision 21. The proposed exemptions do not include an alternative to the ASME Section XI requirements to distribute examinations among the three inspection periods and there is no impact on the technical basis supporting previously approved relief requests applicable to the current ISI interval as provided in Attachment 2 and Regarding the second concern that significant burden would result from licensees needing to reconcile their inspection schedules to conform with the three 4 year periods specified in Code Case N-921, this also does not create any particular challenge. CEG regularly revises the ISI examination schedule mid-interval. Reasons for revising the ISI examination schedule mid-interval include, but are not limited to, dose, availability of examination equipment and personnel, availability of personnel for required support tasks (e.g. insulation, scaffold, weld preparation), outage schedules, outage duration, changes in operating strategy, etc. Maintaining the ISI examination schedule, including mid-interval changes, is core business for ISI program owners and implementation of Code Case N-921 mid-interval does not result in a significant burden, contrary to the commenters assertion. As previously mentioned, during the most recent ISI interval update, CEG took specific actions in anticipation of implementation of Code Case N-921 in the new interval. This includes revision of the period start and end dates and adjusting examination schedules accordingly.
Therefore, because the concerns identified by the NRC in establishing Condition 2 for Code Case N-921 are not applicable to Constellation or can be easily mitigated, the underlying purpose of the rule would continue to be achieved when allowing implementation of Code Case N-921 during the current ISI interval, the special circumstance of 10 CFR 50.12(a)(2)(ii) is present.
Request for Exemptions from Regulatory Guide 1.147, Revision 21, Condition (2) for Code Case N-921 Page 9 of 11 (iii) Compliance would result in undue hardship or other costs that are significantly in excess of those contemplated when the regulation was adopted, or that are significantly in excess of those incurred by others similarly situated.
The Commission has explained that the application of Criterion iii, undue hardship, is narrow. As the Commission stated in the 1985 rule adopting the current exemption criteria, this special circumstance was intended to provide equitable treatment to applicants or licensees who, because of some unusual circumstance, are affected in a manner different than that of other similarly situated licensees or applicants.
(Reference 3) Here, however, Constellation will, in fact, be subjected to an undue hardship as a result of the application of Condition 2 to Code Case N-921. Specifically, limiting Constellation from being able to adopt N-921 for Dresden and Quad Cities would result in inequitable treatment because it would be done on a basis that does not apply to these facilities. As explained above, none of the concerns regarding midcycle adoption of N-921 that underlie Condition 2 are applicable to Constellation or can be easily mitigated. Therefore, it would be fundamentally unfair to preclude Constellations ability to implement the useful improvements to ISI inspections otherwise permitted by N-921.
Therefore, compliance with Section 50.55a(a)(3)(ii) and the related condition imposed on the implementation of Code Case N-921 would result in undue hardship and Special Circumstance 50.12(a)(2)(iii) is present.
(vi) There is present any other material circumstance not considered when the regulation was adopted for which it would be in the public interest to grant an exemption.
There are material circumstances that are present and not considered when the NRC modified 10 CFR 50.55a(a)(3)(ii) and adopted the related Condition 2 for implementation of Code Case N-921. Specifically, the NRC adopted Condition 2 based on a single comment without an opportunity for the industry to provide additional input on whether, in fact, mid-cycle implementation of Code Case N-921 would result in the significant burden asserted. Had such input been provided, the NRC would have understood a mid-cycle implementation of Code Case N-921 would not create the significant burden that it anticipated. As explained in this exemption request, the concerns underlying this condition do not exist for CEG.
Therefore, there are material circumstances that are present and not considered when the NRC modified 10 CFR 50.55a(a)(3)(ii) and adopted the related Condition 2 for implementation of Code Case N-921 and Special Circumstance 50.12(a)(2)(vi) is present.
IV.
Environmental Consideration CEG has determined that the requested exemptions meet the categorical exclusion provision in 10 CFR 51.22(c)(25), as the requested licensing action is an exemption from the requirements of the Commission's regulation and (i) there is no significant hazards consideration; (ii) there is no significant changes in the types or significant increase in the
Request for Exemptions from Regulatory Guide 1.147, Revision 21, Condition (2) for Code Case N-921 Page 10 of 11 amounts of any effluents that may be released offsite; (iii) there is no significant increase in individual or cumulative public or occupational radiation exposure; (iv) there is no significant construction impact; (v) there is no significant increase in the potential for or consequences from radiological accidents; and (vi) the requirements from which an exemption is sought involve inspections, scheduling and administrative requirements.
Therefore, in accordance with 10 CFR 51.22(b), no environmental assessment or environmental impact statement needs to be prepared in connection with the proposed exemption request.
V.
Conclusion Based on current ISI examination and testing requirements, the exemptions requested will allow CEG to better levelize distribution of the remaining examinations and tests across future outages and inspection periods within the 12-year ISI interval while still meeting the underlying purpose of the rule. CEG will continue to meet the ASME Section XI requirements to distribute examinations among the three inspection periods. The added flexibility of Code Case N-921 allows CEG to better align periodic examinations and tests with scheduled outages and maintenance work windows, while ensuring a continuous stream of examination data throughout the remainder of the extended ISI interval.
As demonstrated above, CEG considers that this exemption request is in accordance with the criteria of 10 CFR 50.12. Specifically, the requested exemptions are authorized by law, will not present an undue risk to the public health and safety, and is consistent with the common defense and security. Additionally, special circumstances are present as previously described. Based on the nature of this exemption request, CEG has concluded that granting these exemptions would not have an effect on the quality of human health or the environment.
VI.
Reference
- 1. Final Rule, American Society of Mechanical Engineers Code Cases and Update Frequency, 89 Fed. Reg. 58039 (July 17, 2024).
- 2. Final Rule, American Society of Mechanical Engineers 2021-2022 Code Editions, 89 Fed. Reg. 70449 (Aug. 30, 2024).
- 3. Final Rule, Specific Exemptions; Clarification of Standards, 50 Fed. Reg. 50764 (Dec.
12, 1985).
- 4. U.S. NRC Regulatory Guide 1.147, Revision 21, Inservice Inspection Code Case Acceptability, ASME Code Section XI, Division 1, dated March 2024.
- 5. ASME Section XI, Division 1, Code Case N-921, Alternative 12-yr Inspection Interval Duration dated September 28, 2021.
- 6. America Society of Mechanical Engineers, Boiler and Pressure Vessel Code,Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components, 2017 Edition.
Request for Exemptions from Regulatory Guide 1.147, Revision 21, Condition (2) for Code Case N-921 Page 11 of 11
- 7. America Society of Mechanical Engineers, Boiler and Pressure Vessel Code,Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components, 2019 Edition.
- 8. American Society of Mechanical Engineers Code Case and Update Frequency, dated June 14, 2023. (ML23235A158).
- 9. NRC Responses to Public Comments, Final Rule: American Society of Mechanical Engineers Code Cases and Update Frequency, dated March 2024. (ML23291A328).
ATTACHMENT 2 Dresden Nuclear Power Station, Units 2 and 3 - Assessment of Previously Approved Alternatives Page 1 Dresden Unit 2 & 3 - 6th ISI Interval and 4th CISI Interval Assessment of Previously Approved Alternatives Relief Request Number Description Unit(s)
Affected Submittal Date (Reference)
Approval Date (Reference)
Duration of Approval Impact of 12-yr Interval on Technical Basis Supporting Previous Approval I6R-01 Relief for Inspection of Standby Liquid Control Nozzle Inner Radius 2 & 3 3/25/2022 ML22084A615 12/20/2022 ML22335A544 Alternative is authorized for current duration of the sixth ISI Interval.
No Impact - Geometric configuration of SBLC nozzle results in hardship to perform Code required UT examination. Alternative is to perform a VT-2 examination every refueling outage and maintain compliance with tech spec surveillance for RCPB leakage. Since hardship is due to component configuration and VT-2 examination is required each refueling outage the length of the ISI Interval does not impact the technical basis supporting the proposed alternative.
Page 2 Dresden Unit 2 & 3 - 6th ISI Interval and 4th CISI Interval Assessment of Previously Approved Alternatives Relief Request Number Description Unit(s)
Affected Submittal Date (Reference)
Approval Date (Reference)
Duration of Approval Impact of 12-yr Interval on Technical Basis Supporting Previous Approval I6R-02 Alternative for Testing Frequency for Isolation Condenser Shell Side and Associated Piping 2 & 3 3/25/2022 ML22084A615 11/29/2022 ML22298A280 Alternative is authorized for current duration of the sixth ISI Interval.
No Impact - configuration of the isolation condenser (IC) system results in a hardship to perform Code required system leakage testing each inspection period. Alternative is to perform Code required system leakage testing and VT-2 of the upper and lower portions of the IC shell in conjunction with the tech spec required IC System Heat Removal Capability Verification Test once every 10 years. The frequency of the heat transfer test is determined by Tech Spec surveillance requirement 3.5.3.4 and is not determined by the length of the ISI Interval. In periods the Tech Spec surveillance is not performed, a VT-2 is performed with the IC shell side water level at the normal standby level. A 12-year interval will create three equal 4 year periods and does not impact the technical basis supporting the approved alternative.
Page 3 Dresden Unit 2 & 3 - 6th ISI Interval and 4th CISI Interval Assessment of Previously Approved Alternatives Relief Request Number Description Unit(s)
Affected Submittal Date (Reference)
Approval Date (Reference)
Duration of Approval Impact of 12-yr Interval on Technical Basis Supporting Previous Approval I6R-03 (I4R-10)
Extension of Relief for Alternative Reactor Pressure Vessel Circumferential Weld Examinations for Additional License Operating Period 2 & 3 2/23/2004 ML040620661 3/23/2005 ML050620359 Alternative is authorized for the 20 year period of extended operation which expires on 12/22/2029 for Unit 2 and 1/12/2031 for Unit
- 3.
Not Applicable - Alternative is authorized for the 20 year period of extended operation. Continued use of the alternative beyond the end of the period of extended operation requires resubmittal to the NRC regardless of the length of the ISI Interval.
I6R-04 Proposed alternative was cancelled, number not used.
n/a n/a n/a n/a n/a I6R-05 (I5R-08)
Alternative to Nozzle to Vessel Weld and Inner Radius Examinations
[ASME Code Case N-702]
2 & 3 6/30/2016 ML16187A295 6/28/2017 ML17073A121 Alternative is authorized for the 20 year period of extended operation which expires on 12/22/2029 for Unit 2 and 1/12/2031 for Unit
- 3.
Not Applicable - Alternative is authorized for the 20 year period of extended operation. Continued use of the alternative beyond the end of the period of extended operation requires resubmittal to the NRC regardless of the length of the ISI Interval.
Page 4 Dresden Unit 2 & 3 - 6th ISI Interval and 4th CISI Interval Assessment of Previously Approved Alternatives Relief Request Number Description Unit(s)
Affected Submittal Date (Reference)
Approval Date (Reference)
Duration of Approval Impact of 12-yr Interval on Technical Basis Supporting Previous Approval I6R-06 Alternative Concerning ASME Section XI Repair/Replacement Documentation for Replacement of Pressure Retaining Bolting.
2 & 3 5/18/2021 ML21138A839 12/13/2021 ML21267A317 Alternative is authorized for current duration of the sixth ISI Interval.
No Impact - Alternative eliminates certain R&R documentation requirements for replacement of pressure retaining bolting. This is an administrative requirement and the technical basis supporting the proposed alternative is not impacted by the duration of the ISI Interval.
I6R-07 Proposed Alternative Associated with One-Cycle Reactor Pressure Vessel Water Level Instrumentation Partial Penetration Nozzle Repairs 2 & 3 8/12/2021 ML21224A123 4/15/2022 ML22094A001 Alternative is a contingent repair method if a leaking RPV instrument nozzle is identified.
Alternative is authorized for the operating cycle in which an indication is identified and is currently authorized for the duration of the sixth 10-year ISI Interval.
No Impact - To date, Dresden Unit 2 or 3 have not utilized I6R-07 during the current ISI Interval. Acceptability of the alternative is for a single cycle when an indication is identified and is not impacted by the duration of the ISI Interval.
I6R-08 Proposed Alternative was withdrawn, number not used.
n/a n/a n/a n/a n/a Page 5 Dresden Unit 2 & 3 - 6th ISI Interval and 4th CISI Interval Assessment of Previously Approved Alternatives Relief Request Number Description Unit(s)
Affected Submittal Date (Reference)
Approval Date (Reference)
Duration of Approval Impact of 12-yr Interval on Technical Basis Supporting Previous Approval I6R-09 Synchronization of the CISI Interval for Class MC Components and their Integral Attachments to Coincide with the ISI Interval for Class 1, 2, and 3 Components and their Supports.
2 & 3 7/19/2022 ML22200A258 1/12/2023 ML23003A178 Alternative is authorized to end 3rd CISI interval on January 19, 2023.
Not Applicable - Alternative ended the 3rd CISI Interval for Dresden Unit 2
& 3 on January 19, 2023, which permitted the start of the 4th CISI Interval to coincide with the start of the 6th ISI Interval on January 20, 2023. This alternative is maintained in the ISI Program for historic reference only.
I6R-10 Alternative to Permit Continued Application of Certain ASME Section XI 2013 Edition NDE Requirements for Short Term Fleet Consistency 2 & 3 7/19/2022 ML22200A258 1/6/2022 ML23004A171 Alternative is authorized to use ASME Section XI 2013 Edition for NDE requirements through the end of the first inspection period which is 1/19/2027.
Not Applicable - Alternative is authorized through the end of the first inspection period only. Extension of the ISI Interval end date does not impact this alternative.
ATTACHMENT 3 Quad Cities Nuclear Power Station, Units 1 and 2 - Assessment of Previously Approved Alternatives Page 1 Quad Cities Unit 1 & 2 - 6th ISI Interval and 4th CISI Interval Assessment of Previously Approved Alternatives Relief Request Number Description Unit(s)
Affected Submittal Date (Reference)
Approval Date (Reference)
Duration of Approval Impact of 12-yr Interval on Technical Basis Supporting Previous Approval I5R-11 Relief for the Unit 2 Reactor Pressure Vessel Penetration N-11B Repair.
2 2/14/2017 ML17045A681 1/24/2018 ML18022A616 Alternative authorized until the end of QCNPS, Unit 2, Cycle 27 (spring 2024).
Not Applicable - Authorization has expired. Resubmitted under I6R-10, described below, for continued use beyond Cycle 27.
I6R-01 Relief for Inspection of Standby Liquid Control Nozzle Inner Radius 1 & 2 3/25/2022 ML22084A597 11/30/2022 ML22327A263 Alternative is authorized for current duration of the sixth ISI Interval.
No Impact - Geometric configuration of SBLC nozzle results in hardship to perform Code required UT examination. Alternative is to perform a VT-2 examination every refueling outage and maintain compliance with tech spec surveillance for RCPB leakage. Since hardship is due to component configuration and VT-2 examination is required each refueling outage the length of the ISI Interval does not impact the technical basis supporting proposed alternative.
Page 2 Quad Cities Unit 1 & 2 - 6th ISI Interval and 4th CISI Interval Assessment of Previously Approved Alternatives Relief Request Number Description Unit(s)
Affected Submittal Date (Reference)
Approval Date (Reference)
Duration of Approval Impact of 12-yr Interval on Technical Basis Supporting Previous Approval I6R-02 (I4R-10)
Extension of Relief for Alternative Reactor Vessel Circumferential Weld Examinations for Additional License Operating Period.
1 & 2 2/23/2004 ML040620661 3/23/2005 ML050620359 Alternative is authorized for the 20 year period of extended operation which expires on 12/14/2032 for both Unit 1 and Unit 2.
Not Applicable - Alternative is authorized for the 20 year period of extended operation. Continued use of the alternative beyond the end of the period of extended operation requires resubmittal to the NRC regardless of the length of the ISI Interval.
I6R-03 Proposed alternative was cancelled, number not used.
n/a n/a n/a n/a n/a I6R-04 (I5R-07)
Alternative to Nozzle to Vessel Weld and Inner Radius Examinations
[ASME Code Case N-702]
1 & 2 12/19/2016 ML16354A749 8/25/2017 ML17221A264 Alternative is authorized for the 20 year period of extended operation which expires on 12/14/2032 for both Unit 1 and Unit 2.
Not Applicable - Alternative is authorized for the 20 year period of extended operation. Continued use of the alternative beyond the end of the period of extended operation requires resubmittal to the NRC regardless of the length of the ISI Interval.
I6R-05 Proposed alternative was cancelled, number not used.
n/a n/a n/a n/a n/a Page 3 Quad Cities Unit 1 & 2 - 6th ISI Interval and 4th CISI Interval Assessment of Previously Approved Alternatives Relief Request Number Description Unit(s)
Affected Submittal Date (Reference)
Approval Date (Reference)
Duration of Approval Impact of 12-yr Interval on Technical Basis Supporting Previous Approval I6R-06 Alternative Concerning ASME Section XI Repair/Replacement Documentation for Replacement of Pressure Retaining Bolting.
1& 2 5/18/2021 ML21138A839 12/13/2021 ML21267A317 Alternative is authorized for current duration of the sixth ISI Interval.
No Impact - Alternative eliminates certain R&R documentation requirements for replacement of pressure retaining bolting. This is an administrative requirement and the technical basis supporting the proposed alternative is not impacted by the duration of the ISI Interval.
I6R-07 Proposed Alternative Associated with One-Cycle Reactor Pressure Vessel Water Level Instrumentation Partial Penetration Nozzle Repairs 1 & 2 8/12/2021 ML21224A123 4/15/2022 ML22094A001 Alternative is a contingent repair method if a leaking RPV instrument nozzle is identified.
Alternative is authorized for the operating cycle in which an indication is identified and is currently authorized for the duration of the sixth 10-year ISI Interval.
No Impact - To date, Quad Cities Unit 1 or 2 have not utilized I6R-07 during the current ISI Interval.
Acceptability of the alternative is for a single cycle when an indication is identified and is not impacted by the duration of the ISI Interval.
Page 4 Quad Cities Unit 1 & 2 - 6th ISI Interval and 4th CISI Interval Assessment of Previously Approved Alternatives Relief Request Number Description Unit(s)
Affected Submittal Date (Reference)
Approval Date (Reference)
Duration of Approval Impact of 12-yr Interval on Technical Basis Supporting Previous Approval I6R-08 Proposed alternative was previously submitted but withdrawn, number not used n/a n/a n/a n/a n/a I6R-09 Alternative to Permit Continued Application of Certain ASME Section XI 2013 Edition NDE Requirements for Short Term Fleet Consistency 1 & 2 7/25/2022 ML22206A143 2/3/2023 ML23033A098 Alternative is authorized to use ASME Section XI 2013 Edition for NDE requirements through the end of the first inspection period which is 4/1/2027.
Not Applicable - Alternative is authorized through the end of the first inspection period only. Extension of the ISI Interval end date does not impact this alternative.
I6R-10 Relief for the Unit 2 Reactor Pressure Vessel Penetration N-11B Repair 2
12/14/2022 ML22348A205 9/21/2023 ML23206A038 Alternative authorized until the end of QCNPS, Unit 2, Cycle 30 (spring 2030).
Not Applicable - Authorization is only valid through the end of QCNPS, Unit 2, Cycle 30. Continued use of the alternative beyond this time requires resubmittal to the NRC regardless of the length of the ISI Interval.
Page 5 Quad Cities Unit 1 & 2 - 6th ISI Interval and 4th CISI Interval Assessment of Previously Approved Alternatives Relief Request Number Description Unit(s)
Affected Submittal Date (Reference)
Approval Date (Reference)
Duration of Approval Impact of 12-yr Interval on Technical Basis Supporting Previous Approval I6R-11 Proposed Alternative for Temper Bead Weld Repair of the Matting Surfaces of the Reactor Pressure Vessel Head and Shell Flanges 2
4/23/2023 ML23114A378 5/8/2023 ML23125A061 Alternative authorized for use during U2 forced maintenance outage Q2M30 (May 2023).
Not Applicable - Authorization was for contingent RPV flange repairs during Q2M30 (May 2023). Extension of the ISI Interval end date does not impact this alternative.