ML24283A166

Enclosure 2 Clinton Audit Summary RCI and RAIs

ML24283A166
Person / Time
Site:	Clinton
Issue date:	10/23/2024
From:	Ashley Waldron NRC/NMSS/DREFS/EPMB1
To:	Wilson C Constellation Energy Generation
Shared Package
ML24283A161	List: ML24283A164 ML24283A165 ML24283A166
References
Download: ML24283A166 (1)

Text

Enclosure 2 CLINTON POWER STATION, UNIT 1 INITIAL LICENSE RENEWAL APPLICATION ENVIRONMENTAL REVIEW REQUESTS FOR CONFIRMATION OF INFORMATION Regulatory Basis Licensees are required by Title 10 of the Code of Federal Regulations (10 CFR) Part 51.53(c)(1) to submit with its application a separate document entitled Applicant's Environmental ReportOperating License Renewal Stage. The U.S. Nuclear Regulatory Commissions (NRC) regulations at 10 CFR Part 51, which implement section 102(2) of the National Environmental Policy Act of 1969, as amended (NEPA),

include requirements for applicants to provide information as may be useful in aiding the NRC staff in complying with NEPA. As part of its review, the NRC staff is required to prepare a supplemental environmental impact statement (SEIS). Review guidance for the staff is provided in NUREG-1555, Supplement 1, Revision 2, Standard Review Plans for Environmental Reviews for Nuclear Power Plants: Supplement 1 - Operating License Renewal.

Requests for Confirmation of Information (RCIs)

The letter to Christopher D. Wilson, Director, License Renewal at Constellation Energy Generation, LLC (Constellation), dated August 2, 2024 (Agencywide Documents Access and Management System ML24212A221), contained an audit plan for Clinton Power Station (CPS),

which included a list of information needs with unique identifiers. During the environmental audit, the NRC staff reviewed documents that were made available on the applicants electronic information portal in response to the staff audit needs. The staff also participated in breakout sessions with applicant personnel for certain resource areas to gather information that will likely be in the SEIS. To the best of the staffs knowledge, this information on the applicants electronic information portal and discussed in breakout sessions is not currently on the docket or publicly accessible. The NRC staff requests that the applicant submits confirmation that the information gathered from the audit and listed below is correct or provides the associated corrected information.

1)

RCI ALT-1 Confirm the response to Replacement Energy Alternatives, Audit Need, ALT-1. CPS LR ER Section 7.2.2.4 discusses discrete wind as an unreasonable alternative and introduces the wind farm boundaries metric of 85 acres per MW that is found in the cited ER reference DOE 2015.

Because this metric encompasses land beyond what would be required for appropriate spacing of turbines and more respective of legal boundaries rather than minimal space required for spacing on single-owner contiguous land parcels, this metric is not applicable for the wind component of the CPS Renewable and Natural Gas Combination Alternative and not used in the Section 7.2.3.2.1 discussion. The Department of Energy (DOE) metric for the construction footprint of the wind farm, 2.47 acres per MW, accounts for roads, turbine foundation pads, and electrical infrastructure as well as laydown yards for receiving the wind turbines and towers, crane pads, and electrical cable trenching (DOE 2015), pages 103 and 214). Therefore, the 85 acres per megawatt factor leading to the 55,400 acres of land is not applicable and no offsite or adjacent land use impacts are expected.

2 2)

RCI AQN-01 As discussed during the environmental audit and in response to information need AQN-1, confirm that Constellation has not received any notices of violation or non-compliances associated with air emissions from 2022 to date.

3)

RCI AQN-02 As discussed during the environmental audit and in response to information need AQN-2, please confirm the emissions presented in Table 3.3-10 of the Environmental Report (ER)

(ML24045A279) for particulate matter less than 2.5 microns and particulate matter less than 10 microns are reported conservatively using particulate matter calculations.

4)

RCI AQN-03 As discussed during the environmental audit and in response to information need AQN-3, please confirm that the air emissions presented in Table 3.3-10 of the ER (ML24045A279) accounts for all the emissions sources listed in ER Table 3.3-9.

5)

RCI AQN-04 As discussed during the environmental audit and in response to information need AQN-4, please confirm that Constellation estimates annual particulate matter emissions for the cooling towers to be 4.75 tons and this estimate is based on 34 cooling tower cells, a design flow rate of 10,000 gallons per minute per cell, a total design water flow rate of 340,000 gallons per minute, 0.008 percent drift, 190 parts per million total dissolved solids, and 3,672 hours0.00778 days <br />0.187 hours <br />0.00111 weeks <br />2.55696e-4 months <br /> of operation.

6)

RCI AQN-05 As discussed during the environmental audit, in association with document request AQN-5, confirm the following emissions for 2023: carbon monoxide: 1.55 ton; nitrogen oxides: 6.02 tons; particulate matter: 0.23 tons; sulfur dioxide: 0.07 tons; volatile organic matter: 0.26 tons.

7)

RCI AQN-06 As discussed during the environmental audit in association with information need AQN-6, confirm:

Constellation submitted an application to the Illinois Environmental Protection Agency (IEPA) for the renewal of CPSs Federally Enforceable State Operating Permit (FESOP)

No. 07100046 on April 10, 2024 CPSs FESOP No. 07100046 is administratively extended and currently being reviewed by the IEPA The April 10, 2024 renewal application requested removal of exempt emission units from FESOP No. 07100046, including: 755 horsepower (hp) diesel-powered generating set; 380 hp diesel-powered fire pump; 340 hp diesel-powered fire pump; 240 hp diesel-powered pump; 255 hp diesel-powered generating set; 68 hp diesel-powered generating set; 47 hp diesel powered generating set; 1,500 gallon gasoline above ground storage tank, 15,000 gallon dirty turbine oil storage tank; 18,000 gallon oil separator; 13,000 gallon oil separator; (3) part washers The April 10, 2024, renewal application did not request additional sources be added to CPSs FESOP Permit No. 07100046.

3 8)

RCI SW-01 Confirm that there have been no notices of violation (NOVs) associated with wastewater discharges issued to CPS since 2022. Two NPDES permit non-compliance issues occurred in 2023. On July 18, 2023, chlorination occurred at Outfall 002, but a sample was collected for total residual chlorine (TRC) analysis 22 minutes outside of the required sampling timeframe.

The TRC result for the sample collected was <0.05 parts per million. This permit non-compliance issue was reported in the discharge monitoring report (DMR) for July 2023.

Constellation revised internal procedures to prevent recurrence.

CPS was shut down during a refueling outage in September 2023. Special Condition 22 of the National Pollutant Discharge Elimination System (NPDES) Permit No. IL0036919 requires notifying the Illinois Department of Natural Resources (IDNR) Region III Office and the IEPA Champaign Regional Office of planned shutdown due to refueling 1 week prior to the shutdown.

Notifications were made to these agencies less than 1 week prior to September 2023 refueling shutdown. There are not reporting requirements associated with the untimely notification.

Constellation updated a model work order for plant outage shutdown in include a task to notify IDNR and IEPA of the planned shutdown for refueling 1 week prior to the planned shutdown.

9)

RCI SW-03 Confirm the 2023 CPS surface water withdrawal values in the table below.

Monthly Average (MGM)

Monthly Minimum (MGM)

Monthly Maximum (MGM)

Yearly Total (MGY) 21,963.69 12,667.34 28,975.82 263,564 MGM = million gallons per month MGY = million gallons per year 10)

RCI SW-06 Confirm that while the NPDES permit renewal application is still under development, material changes from the current permit are not anticipated in the future renewed NPDES permit.

11)

RCI SW-07 Confirm that the elevations reported in ER Section 3.6 are based on mean sea level (MSL).

12)

RCI SW-08 Confirm that there have been two down powers (on September 2, 2022, and September 9, 2024) due to thermal limits, since the mechanical draft cooling towers (MDCTs) were installed.

Both down powers occurred to maintain the thermal discharge temperature below 99°F to ensure that the number of days greater than 99°F is within NPDES permit requirements.

Per 35 Illinois Administrative Code (IAC) 309.202(c)(6), a construction permit was not required for the helper cooling towers installation, although a courtesy notification was made to the IEPA Bureau of Water on August 1, 2018.

4 13)

RCI SW-10 Confirm that, per the State of Illinois Water Use Act of 1983, CPS does not have an explicit annual limit on water withdrawals from Clinton Lake.

14)

RCI SW-11 Confirm that the equipment used to measure cooling water discharge temperatures presented in ER Figure 3.6-4 was changed in June 2021 and that this equipment change revealed that the post-June 2021 equipment provides accurate temperature measurements, and the pre-June 2021 data presented in ER Figure 3.6-4 are biased high.

15)

RCI SW-13 Confirm that the following statements are accurate regarding the CPS Spill Prevention, Control, and Countermeasures (SPCC) Plan, dated December 2021 prepared pursuant to 40 CFR Part 112:

CPS is required to review and evaluate the plan at least once every 5 years.

The plan will be amended with 6 months of a change that materially affects the facilitys potential for discharge.

USEPA may require that the plan be amended following reportable spills.

16)

RCI SW-18 Confirm that CPS operates, inspects, and maintains the Clinton Lake Dam and its appurtenances in accordance with approved plans and in accordance with the latest edition of the Rules for Construction and Maintenance of Dams adopted by the Illinois Department of Transportation.

17)

RCI SW-19 Please confirm the 2019 through 2023 stormwater inspection reports conducted in accordance with Special Condition Number 14.R of NPDES Permit No. IL0036919 found the following:

No new evidence of erosion was observed.

No spills or leaks were identified to have occurred in the Outfall 011 drainage area.

No indications of deterioration or off-normal results were observed at Outfall 011.

No changes to the stormwater pollution prevention practices or Stormwater Pollution Prevention Plan (SWPPP) were determined to be necessary, and the facility was determined to be operating in compliance with the SWPPP. In 2023, some additional enhancements were recognized and captured in the CPS Corrective Action Program.

18)

RCI GW-01 Confirm the following statements:

The 2006 evaluation program for groundwater impacts was an initial hydrogeologic investigation report prepared as part of Exelon's fleetwide program to determine whether groundwater had been adversely impacted by any radionuclides releases at its power plants. This report is updated every 5 years, and the most recent update was completed in 2023.

The corporate radiological groundwater protection program (RGPP) described in ER

5 Section 3.6.2.4 was developed to better align the groundwater monitoring programs at Constellation plants with the objectives of the voluntary Groundwater Protection Initiative (GPI) in Nuclear Energy Institute (NEI) 07-07.

19)

RCI GW-02 Confirm the following statements:

There are cable vaults on site in the vicinity of the north-west corner of the turbine building.

The vaults can be accessed via manholes with sumps that collect groundwater.

The vaults are capped with concrete.

The elevation of the top and base of the vaults is approximately 735 ft msl and 725 ft msl, respectively.

The reporting level for Tritium in cable vault water is 2,000 pCi/L. Tritium concentrations greater than 2,000 pCi/L were detected in vault water in February 2013.

Tritium was also detected for the first time in MW-CL-12l (345 pCi/L) in February 2013.

Tritium has been detected above lower limits of detection in MW-CL-21 during sampling events from May 2018 to October 21, 2024.

Cable vault water, collected as a grab sample, is sampled quarterly for tritium as part of the site-specific Potentially Contaminated System Controls Program.

20)

RCI GW-03 Confirm the following statements:

Prior to the installation of 14 monitoring wells in 2006, there were seven groundwater monitoring wells (MW-1 through MW-7) and three piezometers (B-1 through B-3) on the CPS site (note, MW-1 is also known as ML-CL-1 and MW-2 is also known as ML-CL-2).

The 14 monitoring wells installed in 2006 and three of the monitoring locations that were already onsite prior to 2006 are included in the current RGPP, which consists of 17 monitoring locations.

Monitoring wells MW-3 through MW-7 and piezometers B1 and B2 are idle (e.g., not sampled), but it is unknown if these locations were plugged and abandoned or are still in place.

21)

RCI GW-06 Per information provided during the audit, please confirm the following statements:

The passive drainage system of the Unit 2 Pit serves as a continual collection point for shallow groundwater and stormwater.

Groundwater and stormwater collected in the Unit 2 passive drainage system is discharged to Clinton Lake via piping immediately south of the screenhouse. The outfall of the pipe is above the surface of the lake.

There are no samples collected or flow measurements taken at the Unit 2 outfall or within the Unit 2 passive drainage system.

An average flow rate of 47.2 gallons per minute and a total flow of 6,370 gallons during a 135-minute storm event on October 30, 1991, from Outfall 013 (Unit 2 Pit Stormwater Drain) were reported in the Illinois Power Submission of Application for Authorization to

6 Discharge Currently Unpermitted Stormwaters from the Clinton Power Station to Clinton Lake (dated October 1, 1992) provided during the virtual audit.

Illinois Power requested the Unit 2 passive drainage system to be a NPDES-permitted outfall in 1992 (referred to as Outfall 013). In 2011, Exelon then issued a letter to the IEPA requesting Outfall 013 (among others) be exempt from Special Condition 14 -

Stormwater Pollution Prevention Plan. The exemption request was made on the basis that CPS certified there were no discharges of stormwater contaminated by exposure to industrial activities or material from the industrial facility for the drainage area of Outfall 013 (e.g., the Unit 2 Pit). In 2011, the IEPA issued NPDES Permit No. IL0036916 with no monitoring requirements for the Unit 2 Pit passive drainage system.

The current NPDES Permit (No. IL0036919) does not require monitoring of the water that enters the Unit 2 passive drainage system because it is not an area contributing to stormwater discharge associated with industrial activity.

Per station procedure CY-CL-170-2110, potable water withdrawn from Lake Clinton via the Screen House is sampled at the Service Building water compositor quarterly for tritium and monthly for isotopic activity. Isotopic activity has not been detected in samples and tritium concentration has been measured below 2,000 picocuries per liter (pCi/L) for the last 5 years.

22)

RCI GW-08 Confirm the following:

There have been no unplanned radiological releases to date in 2024.

The maximum detected tritium concentration in on-site groundwater samples reported between September 2018 and March 2023 was 1,500 pCi/L, sampled in March 2021.

Tritium concentrations have been sampled below 1,500 pCi/L in onsite groundwater since March 2021.

23)

RCI TER-01 From the information gathered during the audit, please confirm the characteristics of each meteorological evaluation towers (MET) as follows: 1) the primary MET is 205 feet above ground level (AGL), guyed, and lighted with strobing white lights, 2) the backup MET is 250 feet AGL, guyed, and lighted with strobing white lights.

24)

RCI TER-02 From the information gathered during the audit, please confirm the height above ground level (rounded to the nearest foot) for the five following buildings or structures on the CPS site:

Containment/Reactor Building - 92 feet Containment Dome/Gas Control Boundary - 191 feet (tallest building at CPS site)

Aux/Fuel Buildings - 64 feet Control Building - 112 feet Turbine Building - 137 feet

7 25)

RCI TER-03 From the information gathered during the audit, please confirm the following about the osprey nest located on the CPS site: 1) an osprey nest is located on the primary MET, 2) since the nest was first observed in August 2021, no young have been observed, 3) Constellation has no current plans to remove nest.

26)

RCI TER-04 From the information gathered during the audit, please confirm the following about Constellations grassland restoration project under transmission rights-of-way: 1) the project has been on-going since 2016 and covers approximately 65 acres; 2) in-scope transmission lines are mostly over impervious surfaces and are not part of the grassland restoration; 3) the objective of the grassland restoration project is to create an area to contain grassland plants that attract pollinators; 4) pollinator signage exists within the grassland restoration area; 5) the grassland restoration project is in partnership with the U.S. Fish and Wildlife Service (FWS) and that an agreement exists with guidelines on best management practices, herbicide mixing and application, and other procedures to benefit pollinators; 6) that milkweeds (Asclepias spp.) are present within the grassland restoration area and licensed area; and 7) there are no observations of violets (Viola spp.) within the grassland area and licensed area.

27)

RCI TER-05 From the information gathered during the audit, please confirm the following about deterring Canada goose nesting: 1) Although Agrilaser systems were purchased in 2020 to deter nesting, they were never installed because of potential worker safety concerns and 2) To deter nesting, Constellation uses an external vendor with a valid migratory bird permit for handling geese and their nests.

28)

RCI TER-06 From the information gathered during the audit, please confirm the following information regarding migratory birds protected under the Migratory Bird Treaty Act (50 CFR Part 10 and

20) and the Endangered Species Act (16 USC 1531): 1) NRC staff have been provided Constellations proprietary Avian and Wildlife Management Plan for review; 2) Constellations Avian and Wildlife Management Plan contains measures, precautions, and guidance to handle the discovery of dead or injured wildlife; 3) Constellation coordinates with FWS and state agencies regarding management of federally listed species, state listed species, and migratory birds; and 4) Constellation contracts with vendors who have migratory bird permits to handle migratory birds and their nests.

29)

RCI TER-07 From the information gathered during the audit, please confirm the following: 1) Constellation provided the NRC staff its proprietary Pesticide Management Plan for review and 2)

Constellations Pesticide Management Plan contains measures, precautions, and guidance on pesticide and herbicide application, safety, and maintenance.

30)

RCI AQU-01 From the information gathered during the environmental site audit, please confirm that there

8 were no instances prior to the installation of the MDCTs where discharge temperatures exceeded NPDES permit limits.

31)

RCI AQU-02 From the information gathered during the environmental site audit, please confirm that the MDCTs can be run 153 days each year and that the thermal discharge has been greater than 99°F for 54 days as of August 6, 2024, and was greater than 99°F for 82 days in 2023, 86 days in 2022, 85 days in 2021, and 82 days in 2020.

32)

RCI AQU-03 From the information gathered during the environmental site audit, please confirm that the MDCTs are capable of decreasing the discharge temperature by 5.4°F.

33)

RCI AQU-07 From the information gathered during the environmental site audit, please confirm that the last intake inspection was conducted in 2003, and, at that time, no live Corbicula or zebra mussels were observed. Additionally, confirm that no live or dead salamander mussels were observed.

34)

RCI AQU-10 From the information gathered during the environmental site audit, please confirm the following:

From April 5, 2005, to March 29, 2007, Strategic Environmental Actions Inc. collected weekly impingement samples for Exelon Nuclear at the CPS intake structure. Impingement at the intake structure was characterized by large numbers of gizzard shad during cooler months and low numbers of all species in the summer months. Almost all the fish were dead or moribund. The five most frequently impinged speciesgizzard shad (91.8% year 1, 99.99% year 2), freshwater drum, bluegill, white bass, and black crappiemade up more than 99% of the samples. The total number of fish impinged in year 1 was 615,278, while in year 2 it rose to 16,575,647 due to a large increase in gizzard shad. The number of fish impinged per million gallons of intake flow was 2.56 fish in year 1 and 71.9 fish in year 2. Impingement rates appeared to be inversely related to intake flow, with the lowest impingement rates in summer during the highest flow rates and the highest impingement rates in cooler months when flow rates are lowest. Confirm there is a correlation with increased impingement and cooler water temperatures, with the highest impingement rates in March when water temperatures were the lowest.

35)

RCI AQU-13 From the information gathered during the environmental site audit, please confirm that the UHS is inspected yearly to determine if dredging is needed based on current sediment levels. At the last inspection (fall 2023) the UHS level was 896-acre feet and the dredging action level is 849 acre feet. The UHS was last dredged in 1991, and the applicant anticipates the UHS will need to be dredged during the LR period.

9 36)

RCI AQU-14 From the information gathered during the environmental site audit, please confirm that following discussions between CPS and the IDNR State Fish Chief regarding the fish kills that occurred in the early 2000s, additional precautions were taken during plant shutdowns to prevent future fish kills related to cold shock.

37)

RCI FPE-02 Confirm that no surveys have been conducted to identify suitable roosting trees for listed bats to include the Indiana bat (Myotis sodalist), northern long-eared bat (Myotis septentrionalis), and tricolored bat (Perimyotis subflavus).

38)

RCI FPE-06 Confirm that the salamander mussel was not observed or identified during cooling water intake structure (CWIS) monitoring or any other aquatic survey. Additionally, please confirm the salamander mussels only known host for reproduction, the mudpuppy (Necturus maculosus),

has not been observed during any aquatic survey.

39)

RCI HCR-01 As discussed during the environmental audits Historic and Cultural Resources breakout session and in response to information need HCR-1, confirm the following information:

Surveys were conducted prior to the construction of Clinton Power Station and creation of the Lake Clinton. The Illinois CRM Report Archive shows that surveys total over 17,281 acres. Dates of surveys range over a 50-year period.

Based on this information, it is not clear which areas have been previously surveyed for archaeological and architectural resources in relation to the LRs 13,626-acre APE.

40)

RCI HCR-02 As discussed during the environmental audits Historic and Cultural Resources breakout session and in response to information need HCR-2, confirm that the acreage that Constellation owns and operates is 13,531 acres, not 13,626 acres.

41)

RCI HCR-04 As discussed during the environmental audits Historic and Cultural Resources breakout session and in response to information need HCR-4, confirm:

no ground-disturbing activities have occurred since 2008, hence why no archaeological surveys been performed since then the ISFSI will need to be expanded and that the new pad would be located in previously disturbed areas (to the east of the current location)

With respect to what is considered disturbed vs. undisturbed, confirm that because Constellation does not have cultural resources staff, Constellation consults with the Illinois

10 SHPO to determine if archaeological surveys should occur in undisturbed areas outside of the Protected Area within the Clinton site.

42)

RCI HCR-05 As discussed during the environmental audits Historic and Cultural Resources breakout session and in response to information need HCR-5, confirm that the Pabst site is within the vicinity of the Ultimate Heat Sink berm and if there were any remnants of the site still present, it would be underneath the berm. Confirm that dredging would not impact the berm or go beneath it.

43)

RCI HCR-06 As discussed during the environmental audits Historic and Cultural Resources breakout session and in response to information need HCR-6, confirm:

Constellation considers the entire 13,626 acres as previously surveyed (i.e., disturbed).

Constellation keeps a record of archaeological surveys in their electronic data management system. Older surveys completed prior to the transition of ownership from Ameren to Exelon/Constellation are not available, therefore not within their management system.

Any planned land disturbance greater than one acre or greater is governed under NPDES regulations and requires written authorization from the IEPA under their Construction Site Activities General NPDES permit. To obtain authorization, consultation with the IDNR and SHPO is required as documented by submittal of the notice of intent for coverage and a copy of Illinois SHPO concurring on the project.

Constellation defers to engagement with the Illinois SHPO on whether archaeological surveys should occur prior to ground disturbance.

Constellation contracts on a case-by-case basis with the Illinois State Museum to curate any artifacts collected during excavation. Additionally, Constellation has not collected artifacts during ground-disturbing activities.

44)

RCI HCR-07 During the environmental audits Historic and Cultural Resources breakout session and in the follow-up response to information need HCR-7, confirm that Constellation does not have a specific Inadvertent Discovery Plan regarding the discovery of human remains, but upon discovery, would engage their site security team, who would then engage with the local law enforcement. If remains are over 100 years old, the Illinois State Historic Preservation Office takes over jurisdiction. If remains are less than 100 years old, the coroner maintains jurisdiction.

In Illinois, human remains and associated burial artifacts are protected by the Human Skeletal Remains Protection Act.

45)

RCI SOC-01 Based on the ER and subsequent discussions with Constellation, confirm the tax revenues for DeWitt County as indicated in the table below. Of those other districts receiving tax revenue attributable to the CPS (column 5 of the table), confirm the Clinton Community Unit School District #15 receives the bulk of these funds. The source information underlying this summary

11 are the hundreds of individual tax payment receipts on the over 100 CPS-related parcels Constellation owns in DeWitt County.

Year DeWitt County Total General Revenue (USD)

DeWitt County Total Property Tax Paid by Constellation (USD)

% of County Total Property Tax Paid by Constellation Additional Amounts Distributed to Districts and Agencies in DeWitt County by Constellation (USD) 2018 6,813,000 1,776,000 26.1 10,953,000 2019 6,798,000 1,787,000 26.3 11,113,000 2020 6,770,000 1,792,000 26.5 10,960,000 2021 8,025,000 1,832,000 22.8 11,685,000 2022 9,054,000 1,855,000 20.5 12,084,000 2023 8,619,000 1,845,000 21.4 12,394,000 USD = U.S. dollars 46)

RCI HH-01 Confirm that program procedures, such as the radiation control program, are updated on as-needed basis and can be updated for system or equipment changes as well as from a self-assessment process. Also confirm there are no proposed changes or upgrades currently being considered for the radiation control program during the license renewal period.

47)

RCI HH-02 Confirm there have been no reported cases of waterborne diseases in the vicinity of the plant since the submission of the subsequent license renewal environmental report, including any updates from the Centers for Disease Control and Prevention (CDCs) National Outbreak Reporting System (NORS) Dashboard (now available in CDCs Bacteria, Enterics, Amoeba, and Mycotics [BEAM] Dashboard) and/or subsequent local information.

48)

RCI HH-03 Confirm that Constellations Cooling Tower Performance Monitoring Program procedure for CPSs two MDCTs includes processes for microbiological population control through the application of oxidizing or non-oxidizing biocides to address any potential for microorganisms such as bacteria, fungi, algae, and Legionella pneumophila.

49)

RCI WM-01 Liquid effluents may originate from two sources at CPS. The first is effluent from the Radioactive Waste Treatment System. The station is licensed to discharge liquid radwaste effluent should it need to do so, but as a matter of station management decisions it has not discharged through the liquid radwaste system since 1992. If the treated waste sample from the radwaste system indicates that the water quality is within limits required for recycling, it is sent to the cycled condensate storage tank for reuse. In the case that station water balance does not allow for recycling, the treated waste is either sent directly back to the Radioactive Waste Treatment

12 System for re-processing or sent to one of two excess water tanks for short-term storage. In the potential case that storage capacity does not develop in the cycle condensate storage system in a reasonable period of time, as determined by the waste accumulation rate, the site may schedule a discharge of liquid waste. If effluents were to be released through this system, sampling is conducted to ensure the releases would be within regulatory limits. The second source of liquid effluents is from potential heat exchanger leaks found in closed cooling water systems that service radioactively contaminated systems. This second source would be considered an abnormal release if it were to occur. The licensee has procedures for the sampling and analysis of the plant service water and shutdown service water effluents for gamma emitting radionuclides and tritium (H-3) as specified in Sections 2.2 and 2.3 of the Offsite Dose Calculation Manual (ODCM). Also, a radiation monitor in the component cooling water system would indicate leakage into this system from the potentially radioactive systems.

Please confirm that the quarterly tritium grab samples for the service water as specified in Sections 2.2 and 2.3 of the ODCM have been collected and analyzed since the site revised the procedures in 2022 and that the results have been below the Lower Limit of Detection (LLD) for tritium.

50)

RCI WM-02 ER Section 2.2.6.5 notes that CPS does not currently (at the time the ER was written) generate or store mixed waste on site. CPS effluent reports, Table 7, for the period of 2019 -2023 reflect mixed waste shipments in 2020 and 2022. ER Section 9.5.13.3 states that Constellation has a conditional exemption from IEPA for low-level mixed waste, in accordance with 40 CFR 266, Subpart N, in place for any mixed waste placed in storage at CPS storage units listed under the exemption. Under this exemption, mixed waste is excluded from the definition of and requirements for hazardous waste. However, mixed wastes that have lost their conditional exemptions or are otherwise not managed under 40 CFR 266, Subpart N, or corresponding state regulations, are immediately subject to the Resource Conservation and Recovery Act (RCRA) rules for hazardous waste. Please confirm that when mixed waste is stored, it is stored in the designated mixed waste drum cage in the Radwaste Building.

51)

RCI WM-03 ER Section 2.2.6.5 discusses low-level radioactive waste, including greater than Class C waste (GTCC). Please confirm there is currently no GTCC stored onsite and that there are no proposed changes or upgrades to the low-level waste program being considered during the license renewal term.

52)

RCI WM-04 CPS is subject to the reporting provisions of 40 CFR Part 110 as it relates to the discharge of oil in such quantities as may be harmful pursuant to Section 311(b)(4) of the Federal Water Pollution Control Act. In section 9.5.3.6 of the ER, the applicant discusses reportable spills and states that for the period of 2018-2022, there were no reportable releases at CPS that have triggered this notification requirement. Please confirm there have been no reportable releases which would trigger this notification requirement since the ER was written up thru when the audit was conducted on August 28, 2024.

13 53)

RCI WM-05 Confirm there have been no reportable unplanned releases of radioactive materials (unplanned/inadvertent radioactive liquid or gaseous releases) which would trigger a notification requirement since the ER was written thru when the audit was conducted on August 28, 2024.

54)

RCI WM-06 Confirm there has been one spill of nonradioactive material since the ER was written (40%

sodium bisulfite) which was discovered on September 18, 2023. The cause of the spill was traced to a burst pipe and approximately 1,450 to 3,390 gallons of material were released. The spill occurred in the flume detox building, on a concrete pad; however, the non-radioactive material flowed to the surrounding area which included a dirt surface and the discharge flume.

The Illinois Emergency Management Agency and Office Homeland Security (IEMA-OHS) was notified of the spill 11 minutes after discovery. The immediate response included: confirmation that associated pumps were no longer active, removal of non-essential personnel from the area, ventilation of the area, and use of absorbent to contain the material. Subsequently, the top layer of affected soil was removed, and the area was rinsed. All soil and wash water were collected for proper disposal. Five soil samples were collected in the affected area to confirm no remaining soil intrusion. The secondary response included a repair of pipe/connections, replacement pumps (as needed), and a leak check to ensure the issue was corrected. On September 22, 2023, a 5 day follow up report concerning this incident was delivered to the IEMA detailing the status of the recommended actions, which were followed. The event is documented and actions to eliminate or prevent reoccurrence are tracked in Constellations Corrective Action Program. As discussed during the audit, the site took corrective actions in response to this event. These actions include repairing the piping connections and replacing pumps as necessary. A Post Maintenance Test (PMT) leak check of piping will be performed prior to use to ensure the leak has been corrected.

55)

RCI SNF-01 Section 2.2.6.4 of the ER states that It is anticipated that the CPS Independent Spent Fuel Storage Installation (ISFSI) may need to be expanded during the LR period of extended operation if the DOE has not taken ownership of the spent nuclear fuel prior to the ISFSI reaching capacity. It is expected that there is enough previously disturbed land area available for this expansion within the site boundary. Please confirm that as discussed during the audit, there is adequate room for such expansion on previously disturbed land adjacent or almost adjacent to the ISFSI (e.g., to the southeast of the current ISFSI).

56)

RCI GHG-CC-02 As discussed during the environmental audits Greenhouse Gas Emissions and Climate Change break-out session and in response to information need GHG-CC-2, confirm:

Sulfur hexafluoride (SF6) is used for main condenser tube leak testing, main control room tracer gas testing, and in two breakers. Pressure in the breakers is monitored as part of the periodic rounds and the breakers sound an alarm when the SF6 pressure is low; Process carbon dioxide (CO2) is used in the emergency diesel generator fire suppression system, for main generator hydrogen displacement during outages to remove hydrogen, and for hydrogen and water chemistry piping repairs; Constellation has procedures and training for performing of SF6 leak testing in place;

14 Emissions calculations are based on fuel usage for stationary combustion sources, SF6 usage and/or leaks, CO2 gas usage, and releases from refrigerants.

Annual emissions (in CO2 equivalents) are as follows:

Source 2023 2022 2021 2020 2019 Station Combustion Sources 262 285 189 368 219 SF6 0

0 259 16 357 CO2 34 25 40 64 11 Hydrofluorocarbons/perfluorocarbons (HFCs/PCFs) refrigerants 730 1,114 389 3,064 2,735 Ozone Depleting Chemicals Refrigerants 154 227 370 2,087 1,018 Total 1,179 1,651 1,246 5,599 4,339

15 CLINTON POWER STATION, UNIT 1 INITIAL LICENSE RENEWAL APPLICATION ENVIRONMENTAL REVIEW REQUESTS FOR ADDITIONAL INFORMATION 57)

RAI GEN-02 REQUIREMENT: 10 CFR Part 51.53(c)(iv) requires that environmental reports contain any new and significant information regarding the environmental impacts of license renewal of which the applicant is aware.

ISSUE: Appendix B of the draft SEIS will list the permits and licenses issued by Federal, State, and local authorities for activities at CPS, as identified in Table 9.1-1 of the ER, dated February 14, 2024 (ML24045A023). As part of the SEIS, the NRC staff must consider whether there have been any changes to operating permits or other requirements.

REQUEST: Provide the relevant updates to Table 9.1-1 that have occurred since the ER was submitted in February 2024. This includes any permits that have expired since submitting the license renewal application to the NRC. Please provide the status of those permits and or renewals.

58)

RAI NOI-01 REQUIREMENT: 10 CFR 51.45(b) requires that environmental reports, in part, contain a description of the environment affected.

ISSUE: During the environmental audit and in response to information needs NOI-1, NOI-2, and NOI-3, Constellation updated and rewrote portions the Noise affected environment (Section 3.4, Noise, of the ER).

REQUEST: Provide updated Section 3.4, Noise, for docketing.

59)

RAI SW-12 REQUIREMENT: 10 CFR 51.53(c)(3)(ii)(D) requires that if the applicant's plant utilizes cooling ponds, an assessment of the impact of the proposed action on groundwater quality must be provided.

ISSUE: As described in NUREG-1437, Clinton Lake meets the definition of a cooling pond. The ER does not provide an assessment of the impact of the proposed action on groundwater quality from the plants utilization of a cooling pond.

REQUEST: Provide an assessment of the impact of the proposed action on groundwater quality from plants utilization of a cooling pond as required by 10 CFR 51.53(c)(3)(ii)(D).

60)

RAI GW-02 REQUIREMENT: 10 CFR 52.45(b) and 52.53(c)(2) requires that the ER include a description of the affected environment.

ISSUE: Geological cross-sections were provided in the applicants ER as Figures 3.5-3a

16 through 3.5-3c. The figures are blurry. An additional cross-section depicting a cable-vault area was provided during the audit.

REQUEST: Provide higher resolution files of Figures 3.5-3a through 3.5-3c.

61)

RAI TER-03 REQUIREMENT: 10 CFR part 51.53(c)(iv) requires that environmental reports contain any new and significant information regarding the environmental impacts of license renewal of which the applicant is aware.

ISSUE: As part of the information needs provided to Constellation, TER-3 asked for a summary of bird mortality reports and individual incidents at the CPS site from 2013 to 2024. Constellation provided the summary of bird mortalities and individual incidents for NRC staff review.

REQUEST: Please provide the summary of 12 bird mortality incidents from 2013 to 2024, totaling 23 birds. Please provide a statement that there were no bird mortalities known from the CPS site in 2013, 2018, 2023, and 2024.

62)

RAI TER-04 REQUIREMENT: Regulatory Guide 4.2, Supp. 1, Rev. 2, Section 3.6, Ecological Resources, subsection Procedures and Protocols states the ER should [d]escribe any site or fleet-wide environmental procedures, wildlife management plans, best management practices, and conservation initiatives undertaken at the site and relevant to terrestrial resources. Relevant procedures and protocol may include landscape maintenance procedures, transmission line ROW maintenance procedures, stormwater management plans, site environmental review procedures that help workers identify and avoid impacts on the ecological environment when performing site activities, and management or conservation plans related to memberships with environmental stewardship councils. 10 CFR 51.53(c)(3)(ii)(E) states that all license renewal applicants shall assess the impact of refurbishment, continued operations, and other license renewal-related construction activities on important plant and animal habitats. Additionally, the applicant shall assess the impact of the proposed action on federally protected ecological resources in accordance with Federal laws protecting such resources, including but not limited to, the Endangered Species Act, the Magnuson-Stevens Fishery Conservation and Management Act, and the National Marine Sanctuaries Act. Additionally, 10 CFR 51.53(c)(3)(ii)(O): Applicants shall provide information about other past, present, and reasonably foreseeable actions occurring in the vicinity of the nuclear plant that may result in a cumulative effect.

ISSUE: During the in-person audit, NRC staff visited the grassland restoration project where signage was observed that indicated involvement with the FWS. Subsequently, the NRC staff reviewed an agreement between Constellation and the FWS concerning the grassland restoration project.

REQUEST: 1) Describe Constellations agreement with the FWS the onsite Grassland Restoration Project (Partners for Fish and Wildlife Program), including best management practices (BMPs), herbicide mixing/application protocols, etc. included in the plan; 2) Indicate whether Constellation will maintain this agreement for the duration of the proposed license renewal term; 3) Please submit with this response a copy of the agreement between Constellation and the FWS dated April 1, 2017.

17 63)

RAI AQU-09 REQUIREMENT: Impingement mortality and entrainment of aquatic organisms (plants with once-through cooling systems or cooling ponds), specifically 10 CFR 51.53(c)(3)(ii)(B).

If the NPDES permitting authority has made BTA determinations for the nuclear power plant pursuant to CWA Section 316(b) in accordance with the current regulations at 40 CFR Part 122 (Ref. 55) and 40 CFR Part 125 (Ref. 56), which were promulgated in 2014 (79 FR 48300) (Ref.

57), and the plant has implemented any associated requirements or those requirements would be implemented before the license renewal period, no additional analysis is required. In such cases, provide with the ER copies of the NPDES permit, CWA Section 316(b) BTA determinations, studies and information submitted to the NPDES permitting agency pursuant to 40 CFR 122.21(r), and relevant correspondence with the permitting agency. In cases where the NPDES permit has expired but has been administratively continued by the permitting authority because of timely renewal application submission (i.e., at least 180 days before the permit expiration date), provide a copy of the permit renewal application. If certain requirements associated with the CWA 316(b) determination have yet to be implemented, provide a timeline for such implementation.

ISSUE: During the environmental audit and in response to audit information needs AQU-09, AQU-11, AQU-24, AQU-26, AQU-31, and AQU-32, Constellation provided copies of aquatic surveys, permits, and studies not previously included in the ER.

REQUEST: Please provide copies of the following documents:

1.

As included in the audit information need response AQU-09, please provide a copy of:

URS Corporation. 2016. Exelon Generation Company, LLC, Clinton Power Station, Final Report. 40 CFR 122.21(r) NPDES APPLICATION REQUIREMENTS FOR FACILITIES WITH COOLING WATER INTAKE STRUCTURES.

2.

As included in the audit information need response AQU-11, please provide a copy of the NPDES permit renewal application.

3.

As included in the audit information need response AQU-24, please provide a copy of:

HDR Engineering, Inc. 2021. Exelon Generation Company, LLC, Clinton Power Station, Final Report. EXELON GENERATION COMPANY, LLC CLINTON POWER STATION 2019-2020 ENTRAINMENT ABUNDANCE CHARACTERIZATION STUDY. Mahwah, New Jersey.

4.

As included in the audit information need response AQU-26, please provide a copy of:

Strategic Environmental Actions Inc., n.d., Exelon Nuclear, Clinton Power Station, Final Draft. Clinton Power Station Impingement Mortality Characterization Study. Forsyth, Illinois.

5.

As included in the audit information need response AQU-31, please provide a copy of Henningson, Durham & Richardson. 2016. Exelon Generation Company, LLC, Clinton Power Station, Appendix B: Studies of the Fish Community in Clinton Lake. Mahwah, New Jersey.

6.

As included in the audit information need response AQU-32, please provide a copy of Illinois Environmental Protection Agency (IEPA). 2021. Clinton Power Station. Exelon Generation Company, LLC - Clinton Power Station, NPDES Permit No. IL0036919, Bureau ID# W0398040001, Final Modified Permit. Springfield, Illinois.

18 64)

RAI AQU-16 REQUIREMENT: Effects of Thermal Effluents on Aquatic Organisms (Plants with Once-Through Cooling Systems or Cooling Ponds), specifically, 10 CFR 51.53(c)(3)(ii)(B).

If the NPDES permitting authority has made a determination under CWA Section 316(a) that thermal effluent limits are sufficiently stringent to assure the protection and propagation of a balanced, indigenous population of shellfish, fish, and wildlife in and on the receiving body of water, and the nuclear power plant has implemented any associated requirements, no additional analysis is required. In such cases, provide with the ER copies of the NPDES permit, CWA Section 316(a) determination, CWA Section 316(a) demonstration studies and other information submitted to the NPDES permitting authority pursuant to CWA 316(a), and relevant correspondence with the permitting agency. In cases where the NPDES permit has expired but has been administratively continued by the permitting authority because of timely renewal application submission (i.e., at least 180 days before the permit expiration date), provide a copy of the permit renewal application. If certain requirements associated with the CWA 316(a) determination have yet to be implemented, provide a timeline for such implementation.

ISSUE: During the environmental audit and in response to audit information needs AQU-16 and AQU-22, Constellation provided copies of thermal surveys and studies not previously included in the ER.

REQUEST: Please provide copies of the following documents:

1.

As included in the audit information need response AQU-16, please provide a copy of:

Henningson, Durham & Richardson. 2016. Exelon Generation Company, LLC. Clinton Power Station. Appendix F: Modeling of the Thermal Discharge from Exelons Clinton Power Station on Clinton Lake. Mahwah, New Jersey.

2.

As included in the audit information need response AQU-22, please provide a copy of:

Henningson, Durham & Richardson. 2016. Exelon Generation Company, LLC. Clinton Power Station. Appendix A: Description of Clinton Lake. Mahwah, New Jersey.

65)

RAI FPE-01 REQUIREMENT: 10 CFR 51.53(c)(3)(ii)(E) requires the following: all license renewal applicants shall assess the impact of refurbishment, continued operations, and other license-renewal-related construction activities on important plant and animal habitats. Additionally, the applicant shall assess the impact of the proposed action on federally protected ecological resources in accordance with Federal laws protecting such resources, including but not limited to, the Endangered Species Act (ESA), the Magnuson-Stevens Fishery Conservation and Management Act, and the National Marine Sanctuaries Act. Additionally, the implementing regulations for Section 7(a)(2) of the ESA define action area as all areas affected directly or indirectly by the Federal action and not merely the immediate area involved 16 in the action (50 CFR 402.02). The action area effectively bounds the analysis of federally listed species and critical habitats because only species and habitats that occur within the action area may be affected by the Federal action.

ISSUE: The ER does not describe or define the ESA action area for the proposed Clinton license renewal.

19 REQUEST: Please describe the ESA action area for the proposed Clinton license renewal.

66)

RAI FPE-03 REQUIREMENT: 10 CFR 51.53(c)(3)(ii)(E) requires the following: all license renewal applicants shall assess the impact of refurbishment, continued operations, and other license-renewal-related construction activities on important plant and animal habitats. Additionally, the applicant shall assess the impact of the proposed action on federally protected ecological resources in accordance with Federal laws protecting such resources, including but not limited to, the Endangered Species Act, the Magnuson-Stevens Fishery Conservation and Management Act, and the National Marine Sanctuaries Act. 10 CFR Part 51.41 requires that licensees submit information that may be useful in aiding the Commission in complying with section 102(2) of NEPA with information in an environmental report that should contain sufficient data to aid the Commission in its development of an independent analysis [10 CFR 51.41(c)].

ISSUE: The FWS has developed a Northern Long-eared Bat Rangewide Determination Key (DKey). A DKey is a logically structured set of questions to assist a user in determining whether a proposed action qualifies for a predetermined consultation outcome based on FWS standing analysis. DKeys typically contain a series of yes/no questions concerning the proposed action.

The NRC staff requires more information to complete the DKey and determine the potential effects of the proposed Clinton license renewal on the northern long-eared bat.

REQUEST: Please provide a copy of responses to the Northern Long-eared Bat Rangewide DKey questions for continued operations of Clinton during the proposed license renewal term.

The Northern Long-eared Bat Rangewide DKey can be accessed on the FWSs Information for Planning and Consultation (IPaC) database at: https://ipac.ecosphere.fws.gov/. Supplementary information on the DKey can be obtained at: https://www.fws.gov/library/collections/northern-long-eared-bat-assisted-determination-key-supplementary-information.

67)

RAI FPE-04 REQUIREMENT: 10 CFR 51.53(c)(3)(ii)(E) requires the following: all license renewal applicants shall assess the impact of refurbishment, continued operations, and other license-renewal-related construction activities on important plant and animal habitats. Additionally, the applicant shall assess the impact of the proposed action on federally protected ecological resources in accordance with Federal laws protecting such resources, including but not limited to, the Endangered Species Act, the Magnuson-Stevens Fishery Conservation and Management Act, and the National Marine Sanctuaries Act. 10 CFR Part 51.41 requires that licensees submit information that may be useful in aiding the Commission in complying with section 102(2) of NEPA with information in an environmental report that should contain sufficient data to aid the Commission in its development of an independent analysis [10 CFR 51.41(c)].

ISSUE: The FWS published a proposed rule to list the tricolored bat (Perimyotis subflavus) as endangered under the Endangered Species Act on September 14, 2022 (87 FR 56381). This species range includes DeWitt County. The ER does not address this species.

REQUEST: Please provide an analysis of the potential impacts of the proposed license renewal on tricolored bat. This analysis should address (1) mortality or injury from collisions with plant structures and vehicles; (2) habitat loss, degradation, disturbance, or fragmentation, and associated effects; and (3) behavioral changes resulting from refurbishment or other site activities, among other impacts relevant to this species that Constellation may identify.

20 68)

RAI FPE-05 REQUIREMENT: 10 CFR 51.53(c)(3)(ii)(E) requires the following: all license renewal applicants shall assess the impact of refurbishment, continued operations, and other license-renewal-related construction activities on important plant and animal habitats. Additionally, the applicant shall assess the impact of the proposed action on federally protected ecological resources in accordance with Federal laws protecting such resources, including but not limited to, the Endangered Species Act, the Magnuson-Stevens Fishery Conservation and Management Act, and the National Marine Sanctuaries Act. 10 CFR Part 51.41 requires that licensees submit information that may be useful in aiding the Commission in complying with section 102(2) of NEPA with information in an environmental report that should contain sufficient data to aid the Commission in its development of an independent analysis [10 CFR 51.41(c)].

ISSUE: The FWS published a proposed rule to list the salamander mussel (Simpsonaias ambigua) as endangered under the Endangered Species Act and to designate critical habitat for this species on August 22, 2023 (88 FR 57223). This species range includes DeWitt County.

The ER does not address this species.

REQUEST: Please discuss whether any aquatic surveys in Lake Clinton have detected this species (including individuals not identified to the species level that may have been salamander mussels) and provide an analysis of the potential impacts of the proposed license renewal on the salamander mussel. This analysis should address (1) impingement of fish species that early life stages of salamander mussels use as hosts; (2) impacts related to water quality, including chemical and thermal effluents; and (3) dredging, among other impacts relevant to this species that Constellation may identify.

69)

RAI FPE-07 REQUIREMENT: 10 CFR 51.53(c)(3)(ii)(E) requires the following: all license renewal applicants shall assess the impact of refurbishment, continued operations, and other license-renewal-related construction activities on important plant and animal habitats. Additionally, the applicant shall assess the impact of the proposed action on federally protected ecological resources in accordance with Federal laws protecting such resources, including but not limited to, the Endangered Species Act, the Magnuson-Stevens Fishery Conservation and Management Act, and the National Marine Sanctuaries Act. 10 CFR Part 51.41 requires that licensees submit information that may be useful in aiding the Commission in complying with section 102(2) of NEPA with information in an environmental report that should contain sufficient data to aid the Commission in its development of an independent analysis [10 CFR 51.41(c)].

ISSUE: The FWSs IPaC database indicates that the whooping crane (Grus americanus) may occur in the action area. The ER does not address this species.

REQUEST: Please provide an analysis of the potential impacts of the proposed license renewal on whooping crane. This analysis should address (1) mortality or injury from collisions with plant structures and vehicles; (2) habitat loss, degradation, disturbance, or fragmentation, and associated effects; and (3) behavioral changes resulting from refurbishment or other site activities, among other impacts relevant to this species that Constellation may identify.

21 70)

RAI FPE-09 REQUIREMENT: 10 CFR 51.53(c)(3)(ii)(E) requires the following: all license renewal applicants shall assess the impact of refurbishment, continued operations, and other license-renewal-related construction activities on important plant and animal habitats. Additionally, the applicant shall assess the impact of the proposed action on federally protected ecological resources in accordance with Federal laws protecting such resources, including but not limited to, the Endangered Species Act, the Magnuson-Stevens Fishery Conservation and Management Act, and the National Marine Sanctuaries Act. Additionally, Regulatory Guide 4.2, Supplement 1, Revision 2, states that the ER should summarize the input of relevant Federal and State agencies with special expertise or jurisdiction over federally protected ecological resources, as applicable. The ER should include copies of correspondence with these agencies in an appendix to the ER.

ISSUE: Appendix C of the ER provides copies of correspondence to the FWS and Illinois Department of Natural Resources (IDNR) dated January 18, 2023, but the ER does not provide responses to these letters.

REQUEST: Please provide any additional correspondence between Constellation and Federal and State natural resource agencies concerning federally protected ecological resources and other important plant and animal species and habitats, including any agency responses to Constellations January 18, 2023, letters to the FWS and IDNR.

71)

RAI FPE-11 REQUIREMENT: 10 CFR 51.53(c)(3)(ii)(E) requires the following: all license renewal applicants shall assess the impact of refurbishment, continued operations, and other license-renewal-related construction activities on important plant and animal habitats. Additionally, the applicant shall assess the impact of the proposed action on federally protected ecological resources in accordance with Federal laws protecting such resources, including but not limited to, the Endangered Species Act, the Magnuson-Stevens Fishery Conservation and Management Act, and the National Marine Sanctuaries Act. Finally, 10 CFR Part 51.41 requires that licensees submit information that may be useful in aiding the Commission in complying with section 102(2) of NEPA with information in an environmental report that should contain sufficient data to aid the Commission in its development of an independent analysis [10 CFR 51.41(c)].

ISSUE: The FWS published a proposed rule to list the Western regal fritillary (Argynnis idalia occidentalis) as threatened under the Endangered Species Act on August 6, 2024 (89 FR 63888). This species range includes De Witt and Grundy counties.

REQUEST: Please provide an analysis of the potential impacts of the proposed license renewal on the Western regal fritillary. This analysis should address (1) habitat loss, degradation, disturbance, or fragmentation, and associated effects to include mowing; (2) herbicide application and management; and (3) behavioral changes resulting from refurbishment or other site activities, among other impacts relevant to this species that Constellation may identify.

72)

RAI HCR-3 REQUIREMENT: 10 CFR 51.45(b) and 10 CFR 51.53(c)(3)(K) requires that environmental reports, in part, contain a description of the environment affected.

22 ISSUE: During the environmental site audit, CEG took photographs in the direction of the location of the Pabst archaeological site which was subject to salvage excavations in the mid-1970s.

REQUEST: Provide the six photographs taken of the general location of the former Pabst archaeological site as observed during the site audit to support the NRCs NHPA Section 106 consultations with Illinois SHPO.

73)

RAI HH-4 REQUIREMENT: 10 CFR 51.53(c)(3)(ii)(H) states that if the applicant's transmission lines that were constructed for the specific purpose of connecting the plant to the transmission system do not meet the recommendations of the National Electric Safety Code (NESC) for preventing electric shock from induced currents, an assessment of the impact of the proposed action on the potential shock hazard from the transmission lines must be provided.

ISSUE: Section 3.10.2 of the ER states that the NESC clearance standards and the 5mA threshold for induced shock are not applicable to the in-scope transmission lines because the licensee states they are part of the electrical supply station. However, this is not consistent with the NESC definitions for electrical supply station, generating station, or substation.

NESC defines electric supply station as:

any building, room, or separate space within which electric supply equipment is located and the interior of which is accessible, as a rule, only to qualified persons. This includes generating stations and substations, including their associated generator, storage battery, transformer, and switchgear rooms or enclosures, but does not include facilities such as pad-mounted equipment and installations in manholes and vaults.

Because the transmission lines are pad-mounted, the NRC does not view in-scope transmission lines as falling within this NESC definition of electrical supply station.

NESC defines generating station as:

a plant wherein electric energy is produced by conversion from some other form of energy (e.g., fossil fuel, chemical, nuclear, solar, mechanical, wind, or hydraulic) by means of suitable apparatus. This includes all generating station auxiliaries and other associated equipment required for the operation of the plant. Not included are stations producing power exclusively for use with communications systems.

NESC defines substation as:

an enclosed assemblage of equipment, e.g., switches, circuit breakers, buses, and transformers, under the control of qualified persons, through which electric energy is passed for the purpose of switching or modifying its characteristics to increase or decrease voltage or control frequency or other characteristics.

Therefore, the NRC does not view the in-scope transmission lines as a part of generating stations because they are not a plant wherein electric energy is produced, nor does NRC view the in-scope transmission lines as part of a substation since they are not enclosed.

23 The ER, Section 3.10.2 also states:

The in-scope transmission lines were designed to meet the requirements of the NESC in effect at the time of construction. Per Section 0.13.B.2 of the current (2017) NESC, existing installations, including maintenance and replacement that currently comply with prior editions of the code, need not be modified to comply with these rules except as may be required for safety reasons by administrative authority.

In this regard, the ER also states that the in-scope transmission lines were designed to meet the NESC provisions at the time construction (circa 1987 or before).

The ER, Section 3.10.2 further states:

The fleet electrical safety procedure was developed to comply with the National Fire Protection Associations electrical safety in the workplace standard and applicable NESC standards.

Please clarify if the electrical safety procedure was developed to comply with applicable NESC standards and the procedure itself points to NESC clearance requirements. Constellations fleet electrical safety procedure, SA-AA-129, Section 4.5.4, Safe Work Practices for Working near Energized Equipment, states that guards are required around all live parts at more than 150 volts to ground unless there is sufficient horizontal or vertical or a combination of these clearances to minimize the possibility of accidental employee contact, where the NESC is then referenced for these clearances. Additionally, the NESC reference in this procedure does not provide a version year and, in discussing the audit need during the audit, Constellation staff indicated that this reference would be for the 2023 version of the NESC. Clearances in the 2023 version of the NESC are provided in Part 2, Section 23, Clearances. NESC clearance standards are part of Constellations own electrical safety procedure and therefore, it appears that Part 2 of the NESC should apply.

The in-scope transmission lines include the 345-kV lines between the nuclear power block and the 345-kV switchyard, which connects the generating unit to the regional grid owned and operated by Ameren and the 138-kV line. During the audit, Constellation stated that the 138-kV line does not need to meet the 5mA threshold because the line had an ac(phase)-to-ground voltage of less than 98-kV per NESC. However, it appears that the 345-kV lines should still be subject to the 5mA NESC provisions and both the 138-kV and the 345-kV lines should be subject to the NESC clearance provisions.

REQUEST: As per 10 CFR 51.53(c)(3)(ii)(H) for the Category 2 issue of electrical shock, please provide either: 1) information showing that the in-scope transmission lines meet the recommendations of the National Electric Safety Code for preventing electric shock from induced currents, or 2) an assessment of the impact of the proposed action on the potential shock hazard from the in-scope transmission lines.

74)

RAI GHG-CC-01 REQUIREMENT: 10 CFR 51.53(c)(3)(ii)(Q) states that applicants shall include an assessment of the effects of any observed and projected changes in climate on environmental resource areas that are affected by license renewal.

24 ISSUE: ER Section 2.2.3.1 states that MDCTs were installed along the discharge flume in 2018 and 2019 to provide additional seasonal cooling to ensure compliance with NPDES permit temperature limits. The ER, however, did not provide changes in climate parameters including changes in or trends of surface water temperatures.

REQUEST: As included in response to audit information need GHG-CC-1, provide a time series figure of the monthly average intake cooling water temperatures and average monthly seasonal intake temperatures for the available period of record. Additionally, provide a discussion and any relevant information as to whether a warming trend has been observed in Clinton Lake.

25 Severe Accident Mitigation Alternatives (SAMA) Analysis Request for Confirmation of Information (RCI)

1) RCI SAMA-1 [Info Need SAMA-1.b.i through 1.b.iv] Section 2.5 of Addendum 2 to Attachment F of the CPS ER summarizes self-assessments and peer reviews underwent by the CPS PRA. It is indicated that for the Internal Events PRAs, an independent review was conducted in December 2018 and November 2019 on the resolutions to all Facts and Observations (F&Os) from the October 2009 peer review. This same closure review also addressed resolutions to F&Os generated from the April 2018 Fire PRA peer review.

Address the following with respect to the F&O closure process:

a.

Confirm that the F&O closure reviews were conducted in accordance with NRC letter dated May 1, 2017, U.S. Nuclear Regulatory Commission Staff Expectations for an Industry Facts and Observations Independent Assessment Process (ML17121A271),

and NRC letter dated May 3, 2017, U.S. Nuclear Regulatory Commission Acceptance on Nuclear Energy Institute Appendix X to Guidance 05-04, 07-12, and 12-13, Close-Out of Facts and Observations (ML17079A427).

b.

Confirm that the scope of the F&O closure reviews included all finding-level F&Os (for the internal events and fire PRAs), including those finding-level F&Os that are associated with Met Supporting Requirements, from the October 2009 and April 2018 peer reviews.

c.

Confirm that the closure review team for each review was provided with a written assessment and justification of whether the resolution of each F&O, within the scope of the independent assessment, constitutes a PRA upgrade or maintenance update, as defined in ASME/ANS RA-Sa-2009, Addenda to ASME/ANS RA-S-2008, Standard for Level 1/Large Early Release Frequency Probabilistic Risk Assessment for Nuclear Power Plant Applications, as qualified by Regulatory Guide 1.200, Revision 2, An Approach for Determining the Technical Adequacy of Probabilistic Risk Assessment Results for Risk-Informed Activities, (ML090410014).

d.

Confirm that the CPS PRA (CL122A/CL122AF0) used in the SAMA analysis in Addendum 2 to Attachment F of the CPS ER incorporates the dispositions to all the formally closed F&Os.

2) RCI SAMA-2 [Info Need SAMA-3.a] Confirm that the freeze date" for the CPS Fire PRA (CL122AF0) used for the SAMA analysis in Addendum 2 to Attachment F of the CPS ER, that is, the date which corresponds to the CPS design and operation incorporated into the CPS Fire PRA, is December 31, 2021, the date referenced in Section 2.1 of Addendum 2 to Attachment F of the CPS ER.

3) RCI SAMA-3 [Info Need SAMA-3.b] Confirm that the basis of the Seismic CDF estimate presented in Section 4.1.2 of Addendum 2 to Attachment F of the CPS ER is the same as that presented in Section 3.2.4.1.3 of the NRC staff safety evaluation of the license amendment request (LAR) for CPS to adopt Technical Specifications Task Force (TSTF)

Traveler TSTF-505 (ADAMS Accession Number ML21132A288).

26 Severe Accident Mitigation Alternatives (SAMA) Analysis Requests for Additional Information (RAI)

4) RAI SAMA-1 REQUIREMENT: Applicants for license renewal are required by 10 CFR 51.53(c)(3)(ii)(L) to consider SAMAs if not previously considered in an environmental impact assessment, related supplement, or environmental assessment for the plant. As part of its review of the CPS SAMA analysis, NRC staff evaluates the applicants treatment of internal events and calculation of core damage frequency in the Level 1 PRA model.

ISSUE: The requested information is needed in order for the NRC staff to reach a conclusion on the sufficiency of the applicants Level 1 PRA model for supporting the SAMA evaluation.

REQUEST: Provide the following information regarding the Level 1 PRA used for the SAMA analysis.

Attachment F of the ER states that the NEI 05-01-A guidance was used in developing the SAMA analysis. Section 3.1 of NEI 05-01-A specifies the information that is to be provided in the ER regarding the Level 1 PRA model and analysis. Some of this information is not provided in the ER. Provide the following information relative to the Level 1 PRA analysis. The requested information is needed for the NRC staff to reach a conclusion on the adequacy of the applicants Level 1 PRA model for supporting the SAMA evaluation.

a.

[Info Need SAMA-1.a] Discuss any major plant modifications or plant changes made since the release of the CPS PRA (CL122A/CL122AF0) used in the SAMA analysis in Addendum 2 to Attachment F of the CPS ER and the impact of these modifications/changes on the SAMA analysis. Also, clarify if there are any planned major plant modifications or changes that could adversely impact the SAMA analysis, and assess the impact of these modification/changes on the results of the SAMA analysis.

b.

[Info Need SAMA-1.b.v] Section 2.5.2 of Addendum 2 to Attachment F of the CPS ER indicates that two F&Os related to the IEPRA were not fully resolved by the December 2018 and November 2019 F&O closure reviews. Additionally, one Fire PRA F&O remains open from the 2022 focused-scope peer review, which was performed after the F&O closure reviews. Address the following:

i.

While the CPS ER dispositions these F&Os in Tables 2.5-1 and 2.5-2 of Addendum 2 to Attachment F, formatting issues prevent information within these tables, as presented within the applicants submitted ER (ADAMS Accession Number ML24045A279), from being fully viewed. Provide re-formatted tables such that the information within these tables is fully visible.

ii.

F&Os 1-32 and 1-34 within Tables 2.5-1 and 2.5-2 of Addendum 2 to Attachment F indicate that a significant underestimation of risk may result from the existing process and solution method used to identify combinations of operator actions for purposes of the HRA dependency analysis. The Independent Review Teams assessment of these F&Os within these tables further highlighted the need to demonstrate that risk-significant combinations of Human Failure Events (HFEs) were adequately captured, suggesting process improvements and confirmatory

27 sensitivity studies. CEG, in its assessment of the impact of these F&Os on the SAMA analysis, performed a review of cutsets and HFE combinations, identifying legitimate dependent combinations that would impact overall risk results but not substantially. However, the scope and degree of the applicants review is not clear. Clarify the approach used to demonstrate that all risk-significant combinations of HFEs are captured by the dependency analysis and justify that the approach used is reasonable for the SAMA analysis (e.g., does not underestimate the estimated benefits of SAMAs).

c.

[Info Need SAMA-1.c] Various sections within Addendum 2 to Attachment F of the CPS ER refer to Diverse and Flexible Mitigation Capability (FLEX) strategies credited within the CPS PRA (e.g., Section 6.0). In an NRC memorandum dated May 30, 2017 (ML17031A269), the NRC staffs positions and conclusions are provided regarding use of guidance in NEI 16-06, Crediting Mitigating Strategies in Risk-Informed Decision Making. In an NRC memorandum dated May 6, 2022, Updated Assessment of Industry Guidance for Crediting Mitigating Strategies in Probabilistic Risk Assessments (ML22014A084), the NRC staff identified challenges and strategies for incorporating FLEX equipment into a PRA model in support of risk-informed decision-making when using additional industry guidance issued after NEI 16-06. Specifically, over-crediting FLEX in the PRA model could underestimate the potential benefit of SAMAs. Address the following:

i.

Describe the FLEX strategies that were credited in the CPS PRA model (inclusive of internal events and fire) used to support the SAMA analysis. Include identification of discussion of the FLEX equipment that was credited and whether that equipment is portable or permanently installed and identification of the operator actions that are credited.

ii.

Clarify the guidance used to model FLEX strategies within the CPS PRA model, identify the NRC memorandum that is applicable to the modeling of FLEX in the CPS PRA model, and explain how each of the 13 NRC staff conclusions are addressed in the PRA.

iii.

If the FLEX modeling is not in accordance with the applicable NRC memorandum, assess the impact on the SAMA analysis.

5) RAI SAMA-2 REQUIREMENT: Applicants for license renewal are required by 10 CFR 51.53(c)(3)(ii)(L) to consider SAMAs if not previously considered in an environmental impact assessment, related supplement, or environmental assessment for the plant. As part of its review of the CPS SAMA analysis, NRC staff evaluates the applicants treatment of accident propagation and radionuclide release in the Level 2 PRA model.

ISSUE: The requested information is needed in order for the NRC staff to reach a conclusion on the adequacy of the applicants Level 2 PRA model for supporting the SAMA evaluation.

REQUEST: Provide the following information relative to the Level 2 PRA analysis.

Attachment F of the ER state that the NEI 05-01-A guidance was used in developing the SAMA analysis. Section 3.2 of NEI 05-01-A specifies the information that is to be provided in the ER

28 regarding the Level 2 PRA model and analysis. Some of this information is not provided in the ER. Provide the following information relative to the Level 2 PRA analysis. The requested information is needed for the NRC staff to reach a conclusion on the adequacy of the applicants Level 2 PRA model for supporting the SAMA evaluation.

[Info Need SAMA-2.a] Section 2.5 of Addendum 2 to Attachment F of the CPS ER summarizes the PRA model development and peer review process, which for the Level 2 analysis only addresses (partially) large early release. In Section 2.3.2, the ER provides only a high-level description of the Level 2 analysis that was developed and applied to produce the results for the containment event tree (CET) end points or source term categories and release categories reported in the ER. Address the following:

i.

Explain how the Level 2 post-core damage accident response analysis is linked to the Level 1 PRA model, including addressing how the Level 1 core damage sequences were binned into plant damage states (PDSs), describing each of the PDSs, and providing the results of this binning process.

ii.

Summarize the CET(s) developed to produce results for each of the CET end states or source term categories (STCs) reported in the ER and the process for progressing each PDS through the CET(s). Include in the response a description of the modeled branch points (both system failures and phenomenological).

iii.

Describe the logic and criteria used in the selection of the representative MAAP case for each release category, or source term category, and provide justification that the selected cases are reasonable for the SAMA analysis (e.g., does not underestimate the estimated benefits of SAMAs).

iv.

Summarize any independent and/or peer reviews performed to provide confidence in the Level 2 analysis, the results of these reviews, the qualifications and expertise of reviewers, and any unresolved independent/peer review comments and their impact on the SAMA analysis.

v.

Sections 2.3.2 and 2.4.2 of Addendum 2 to Attachment F of the CPS ER report LERF estimates of 7.31E-08/year and 2.40E-06/year for the Internal Events and Fire PRA models used in the SAMA analysis. As a comparison, Table 3-1 reports a lower frequency of 8.74E-07/year for ST2 (High/Early) from the Level 2 analysis developed for the SAMA analysis. Explain the reasons for this difference and the extent to which other release categories (e.g., High/Late) may be impacted. Also, provide an assessment of the impact of any differences on the SAMA analysis, including, as applicable, on the population dose risk (PDR) and the offsite economic cost risk (OECR).

b.

[Info Need SAMA-2.b] Section 2.3.2.3 of Addendum 2 to Attachment F of the CPS ER indicates that Table 2.3.2-1 provides a frequency matrix of the radionuclide release categories and the Level 1 accident classes. However, formatting issues prevent information within this table, as presented within the applicants submitted ER (ADAMS Accession Number ML24045A279), from being fully viewed. Similar issues also apply to Table F.2.3.2-1. Provide re-formatted tables such that the information within these tables is fully visible.

29 6)

RAI SAMA-3 REQUIREMENT: Applicants for license renewal are required by 10 CFR 51.53(c)(3)(ii)(L) to consider SAMAs if not previously considered in an environmental impact assessment, related supplement, or environmental assessment for the plant. As part of its review of the CPS SAMA analysis, NRC staff evaluates the applicants treatment of external events in the PRA models.

ISSUE: The requested information is needed in order for the NRC staff to reach a conclusion on the sufficiency of the applicants PRA models for supporting the SAMA evaluation.

REQUEST: Provide the following information with regard to the treatment and inclusion of external events in the SAMA analysis.

Attachment F of the ER state that the NEI 05-01-A guidance was used in developing the SAMA analysis. Section 3.1.2 of NEI 05-01-A specifies the information that is to be provided in the ER regarding the treatment and inclusion of external events in the SAMA analysis. Some of this information is not provided in the ER. Provide the following information relative to the treatment and inclusion of external events in the SAMA analysis. The requested information is needed for the NRC staff to reach a conclusion on the adequacy of the applicants analyses that support the SAMA evaluation.

a.

[Info Need SAMA-3.c] NRC Regulatory Issue Summary (RIS) 2015-06, while not requiring regulatory action, identified several instances in which nuclear power plants were determined to not conform with their tornado-generated missile licensing basis.

Discuss any changes to the CPS site or surrounding environment or to CPS that would change the conclusions of the IPEEE regarding tornado-generated missiles and which could impact the SAMA analysis.

b.

[Info Need SAMA-3.d] Section 4.1.2 of Addendum 2 to Attachment F of the CPS ER explains that other external events, apart from seismic events, were assessed in 2020 using a progressive screening approach. However, related hazards appear to be screened based on an assumption that reflects considerations that are unstated in the ER and were made in support of referenced LARs, specifically 10 CFR 50.69 (ADAMS Accession Number ML21090A193) and TSTF-505 (ADAMS Accession Number ML21132A288). Summarize the screening assessment that was used to address these other external hazards and that forms the basis for the ER conclusion. In the response, discuss the screening criteria used and their applicability to the SAMA analysis, and, specifically, whether changes to the plant, the plant site, or the area surrounding the plant site made since the IPEEE have impacted the conclusions of the IPEEE.

c.

[Info Need SAMA-3.e] Section 2.5.2 of Addendum 2 to Attachment F of the ER indicates that a focused-scope peer review was performed on the Fire Scenario Selection technical element; however, the standard and process guidelines applied are not discussed. Clarify the standard and process guidelines used and justify that the peer review is reasonable for the SAMA analysis.

7)

RAI SAMA-4 REQUIREMENT: Applicants for license renewal are required by 10 CFR 51.53(c)(3)(ii)(L) to consider SAMAs, if not previously considered, in an environmental impact assessment, related supplement, or environmental assessment for the plant. As part of its review of the CPS SAMA

30 analyses, NRC staff evaluates the applicant's analysis of accident consequences in the Level 3 PRA.

ISSUE: The requested information is needed in order for the NRC staff to reach a conclusion on the sufficiency of the applicant's Level 3 PRA model for supporting the SAMA evaluations.

REQUEST: Please provide the following information regarding the Level 3 PRA used in the SAMA analysis.

Attachment F of the ER state that the NEI 05-01-A guidance was used in developing the SAMA analysis. Section 3.4 of NEI 05-01-A specifies the information that is to be provided in the ER regarding the Level 3 PRA model and analysis. Some of this information is not provided in the ER. Provide the following information relative to the Level 3 PRA analysis. The requested information is needed for the NRC staff to reach a conclusion on the adequacy of the applicants Level 3 PRA model for supporting the SAMA evaluation.

a.

[Info Need SAMA-4.a] Table F.3-19 of the CPS ER provides the base case mean Population Dose Risk (PDR) and Offsite Economic Cost Risk (OECR) results using the 2017 CPS PRA model (CL117B/CL117BF0). While Table 3-1 of Addendum 2 to Attachment F provides updated release category frequencies for the 2022 CPS PRA model (CL122A/CL122AF0), updated base case mean PDR and OECR results do not appear to be provided. Moreover, Section 3.0 of Addendum 2 to Attachment F summarizes the base case results for the 2022 CPS PRA model that are equivalent to the 2017 CPS PRA model (i.e., PDR of 68.1 person-rem/year and OECR of

$963,000/year), whereas the Phase 2 SAMA analysis in Section 6.0 makes use of different figures (i.e., PDR of 27.2 person-rem/year and OECR of $404,403/year).

Provide a breakdown of the base case mean PDR and OECR results by release category for the 2022 CPS PRA model, and address discrepancies, if any, that exist with the SAMA analysis performed in Addendum 2 to Attachment F.

b.

[Info Need SAMA-4.b] Section F.3.7 states that the 2020 meteorological data set was used to support the Level 3 model. However, atmospheric mixing height values appear to be based on historical values from a 1972 EPA publication. Explain why the selected data is reasonable for the SAMA analysis (e.g., does not underestimate the estimated benefits of SAMAs), or alternatively provide the results of a sensitivity analysis.

c.

[Info Need SAMA-4.c] Section 7.3.2 of Addendum 2 to Attachment F acknowledges that NUREG/CR-7270 provides updated technical bases for input parameters used in MACCS (MELCOR Accident Consequence Code System) modeling applications and provides a sensitivity study that was performed to assess the impact of this new information on decontamination modeling performed to support the SAMA analysis. This study showed an increase in the PDR of approximately 4% and an increase in OECR of approximately 61%. It is noted that for most of the parameters addressed as part of the sensitivity study and identified in Table 7.3-1 of Addendum 2 to Attachment F, the technical bases documented within NUREG/CR-7270 represent modeling choices that are considered reasonable generic choices and are expected to be applicable for most U.S. locations per Appendix C to NUREG/CR-7270. Given this, justify why the updated technical bases documented within NUREG/CR-7270 for parameters related to decontamination modeling should not be incorporated into the base case used to assess the maximum averted cost risk (MACR) and its contributors, support the SAMA cost-

31 benefit analysis, examine the impact of uncertainty, and support other documented sensitivity studies.

8)

RAI SAMA-5 REQUIREMENT: Applicants for license renewal are required by 10 CFR 51.53(c)(3)(ii)(L) to consider SAMAs if not previously considered in an environmental impact assessment, related supplement, or environmental assessment for the plant. As part of its review of the CPS SAMA analysis, NRC staff evaluates the applicants basis for the selection and screening Phase I SAMA candidates.

ISSUE: The requested information is needed in order for the NRC staff to reach a conclusion on the adequacy of the applicants Phase I SAMA selection and screening process for the SAMA evaluation.

REQUEST: Provide the following information with regard to the selection and screening of Phase I SAMA candidates.

Attachment F of the ER state that the NEI 05-01-A guidance was used in developing the SAMA analysis. Sections 5 and 6 of NEI 05-01-A specifies the information that is to be provided in the ER regarding the selection and screening of Phase I SAMA candidates. Some of this information is not provided in the ER. Provide the following information relative to the Phase I SAMA analysis. The requested information is needed for the NRC staff to reach a conclusion on the adequacy of the applicants analyses that support the SAMA evaluation.

a.

[Info Need SAMA-5.a] Sections F.5.1.1 and F.5.1.2 of the ER describes what cutoff values were assumed in determining dominant risk contributors within the Level 1 and Level 2 importance analyses, respectively. However, the rationale for the cutoff value applied (i.e., a Fussell-Vesely of 0.05) is not clear. For internal events risk, this cutoff value is correlated to an averted cost-risk of $29,000, but a similar comparison is not done to address other hazards (e.g., fire and seismic) and uncertainty. If such a comparison were made, the resulting averted cost-risk (i.e., 0.05 x $11,635,329, without uncertainty, or $35,836,813, with uncertainty) would appear to exceed the implementation costs of many SAMAs identified addressed in Addendum 2 to Attachment F, including those found to be potentially cost-beneficial in Section 8.0.

Justify the rationale for the cutoff value used to determine what is a dominant risk contributor in the context of the SAMA analysis. In doing so, explain why SAMAs identified for contributors below the applied cutoff values would be not cost-beneficial.

b.

[Info Need SAMA-5.b] Section F.6 provides only a brief description of the cost estimating process for determining the implementation cost for the various SAMAs, and some implementation costs within Table 5-3 of Addendum 2 to Attachment F simply reference non-CPS estimates without discussion as to the scope and applicability of the associated modifications/changes. Provide a more detailed description of the cost estimating process and bases used to develop the implementation cost estimate for SAMA candidates, including whom or what organization performed the estimate (or assessed the applicability thereof), what costs are included in the estimate (e.g.,

procurement, installation, long-term maintenance, surveillance, calibration, and training),

and conservatisms in the cost estimates, whether specific to CPS or not. Additionally, this description should speak to how the applicability of non-CPS-specific implementation costs was determined.

32 9)

RAI SAMA-6 REQUIREMENT: Applicants for license renewal are required by 10 CFR 51.53(c)(3)(ii)(L) to consider SAMAs if not previously considered in an environmental impact assessment, related supplement, or environmental assessment for the plant. As part of its review of the CPS Plant SAMA analysis, NRC staff evaluates the applicants cost-benefit analysis of Phase II SAMAs.

ISSUE: The requested information is needed in order for the NRC staff to reach a conclusion on the acceptability of the applicants cost estimations for individual SAMAs and cost-benefit evaluation.

REQUEST: Provide the following information with regard to the Phase II cost-benefit evaluations.

Attachment F of the ER state that the NEI 05-01-A guidance was used in developing the SAMA analysis. Sections 7 and 8 of NEI 05-01-A specifies the information that is to be provided in the ER regarding the Phase II cost-benefit and sensitivity evaluations. Some of this information is not provided in the ER. Provide the following information relative to the Phase II SAMA analysis and sensitivity evaluations. The requested information is needed for the NRC staff to reach a conclusion on the adequacy of the applicants analyses that support the SAMA evaluation.

a.

[Info Need SAMA-6.a] Section 6.2 of Addendum 2 to Attachment F of the CPS ER indicates that the benefit of SAMA 3 is at least partially derived from the RCIC (Reactor Core Isolation Cooling) storage tank being protected; however, it is not clear what this protection entails and how it addresses associated dominant contributors in Tables 5-1 and 5-2. Clarify what modifications/changes are being proposed to protect the RCIC storage tank and summarize how they serve to address identified dominant contributors.

b.

[Info Need SAMA-6.b] Section 6.4 of Addendum 2 to Attachment F of the CPS ER indicates that SAMA 5 is modeled by reducing the HEP (Human Error Probability) associated with bus realignment and that it is assumed that SAMA 5 reduces the execution time for bus realignment from 60 to 30 minutes. However, the cost estimate for SAMA 5 within Table 5-3 suggests that this SAMA would eliminate the need for local breaker manipulation and provide the main control room with remote alignment capability. Provide further justification for HEP-related modeling assumptions or demonstrate that such assumptions do not impact the results of the SAMA analysis.

c.

[Info Need SAMA-6.c] Section 6.25 of Addendum 2 to Attachment F of the CPS ER indicates that risk-significant conduits are re-routed from Fire Zone CB-5A to Fire Zone CB-1G but that these conduits are then assumed to be failed for all fires originating in Fire Zone CB-1G. Provide further justification for this modeling assumption or demonstrate that it does not impact the results of the SAMA analysis.

10)

RAI SAMA-7 REQUIREMENT: Applicants for license renewal are required by 10 CFR 51.53(c)(3)(ii)(L) to consider SAMAs if not previously considered in an environmental impact assessment, related supplement, or environmental assessment for the plant. As part of its review of the CPS SAMA analysis, NRC staff considers additional SAMAs that may be more effective or have lower implementation costs than the other SAMAs evaluated by the applicant.

33 ISSUE: The requested information is needed in order for the NRC staff to reach a conclusion on the adequacy of the applicants determination of cost-beneficial SAMAs.

REQUEST: For certain SAMAs considered in the CPS ER, there may be lower cost or more effective alternatives that could achieve much of the risk reduction. In this regard, provide an evaluation of the following SAMA.

Attachment F of the ER state that the NEI 05-01-A guidance was used in developing the SAMA analysis. Section 2 of NEI 05-01-A notes that potentially cost-beneficial SAMAs are most likely to be procedure changes and minimal hardware changes. As part of its review of the CPS SAMA analysis, the NRC staff considers additional SAMAs that may be more effective or have lower implementation costs than the other SAMAs evaluated by the applicant. The requested information is needed for the NRC staff to reach a conclusion on the adequacy of the applicants analyses that support the SAMA evaluation.

a.

[Info Need SAMA-7.a] Table 5-3 of Addendum 2 to Appendix F of the CPS ER cost estimate indicates that SAMA 5, which addresses the installation of an emergency tie line from the switchyard to an emergency bus, is based on an estimate developed for a potentially cost beneficial SAMA at Wolf Creek Generating Station (WCGS). It is noted that given the $400,000 cost estimate and scope of SAMA 5, the WCGS SAMA upon which the estimate is based appears to be SAMA 2 from the Supplement 32 to NUREG-1437 (ADAMS Accession Number ML081260608), which includes, among other changes, hardware modifications to allow the remote start and alignment of ten diesel generators at a local generating station. Confirm the WCGS SAMA upon which the SAMA 5 cost estimate is based and justify how its scope is appropriate for SAMA 5 (e.g.,

does not overestimate the implementation cost).

b.

[Info Need SAMA-7.b] Section 8.0 of Addendum 2 to Attachment F of the CPS ER identifies ten potentially cost-beneficial SAMAs based on the SAMA analysis using the 2022 CPS PRA model (CL122A/CL122AF0); however, there appears to be no discussion indicating whether these SAMA candidates will be formally evaluated for potential implementation at the plant. Clarify that all potentially cost-beneficial SAMAs will be formally evaluated for potential implementation at the plant.