ML24366A028

Audit Summary - RCI and RAI Enclosure v2.23clean

ML24366A028
Person / Time
Site:	Dresden
Issue date:	12/21/2024
From:	Office of Nuclear Material Safety and Safeguards
To:
References
Download: ML24366A028 (31)

Text

DRAFT 12/21/2024 DRESDEN POWER STATION, UNITS 2 & 3 INITIAL LICENSE RENEWAL APPLICATION ENVIRONMENTAL REVIEW REQUESTS FOR CONFIRMATION OF INFORMATION w/Track changes

DRESDEN POWER STATION, UNITS 2 & 3 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 September 23, 2024 (Agencywide Documents Access and Management System ML24253A094), contained an audit plan for Dresden Nuclear Power Station (Dresden), 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)

AQN-01 Please confirm that DNPS conducts firefighting training for its personnel to manage potential emergencies. The open burn permit is to have the ability to train firefighters in controlled situations.

2)

AQN-02 Please confirm that ER Table 3.3-10 accounts for all the emission sources listed in Table 3.3-9 of the ER. Additionally, please confirm that 2023 annual air emissions are as follows:

Particulate Matter: 23.50 tons Particulate Matter less than 10 microns: 22.18 tons Sulfur Dioxide: 0.01 tons Nitrogen Oxides: 7.79 tons Carbon Monoxide: 3.29 tons Volatile Organic Matter: 0.35 tons

3)

AQN-03 Please confirm that Constellation has not received any notices of violation or non-compliances associated with DNPSs Federally Enforceable State Operation Permit from 2023 to October 2024.

4)

AQN-04 Confirm the following information provided in response to document need AQN-4:

On March 31, 2024, Constellation submitted an application to the Illinois Environmental Protection Agency for the renewal of DNPSs Federally Enforceable State Operation Permit (FESOP) Number 73020783.

Dresdens FESOP No. 73020783 is administratively extended and currently being reviewed by the Illinois Environmental Protection Agency.

The March 31, 2024 renewal application requested removal of exempt emission units from FESOP No. 73020783 including the small diesel-powered emergency

generators (1,500 horsepower each or smaller) and the gasoline storage and handling.

The March 31, 2024 renewal application did not request additional sources be added to Dresdens FESOP No. 73020783.

The open burn permit was renewed and issued on February 23, 2024. Permit allows a maximum of 350 gallons of gasoline, 100 gallons of propane, 1,000 pounds of wood/straw, 250 gallons of #1 and #2 distillate oil/kerosene, 100 pounds of paper per session for fire fighting training.

5)

NOI-01 Section 3.4 of the ER states that in 2017, DNPS completed a two-phase noise evaluation which found that cooling tower noise levels were 58 dBA at the nearest residence and exceeded Illinois nighttime limits of 51 dBA for residential receivers. The ER also identifies that Constellation will support the planting of 150 evergreen trees to mitigate noise to offsite residences. As discussed during the Noise break out session and in response to information need NOI-1, please confirm:

in 2016, Constellation installed sound absorbing filters at the south/southeast areas of the hot canal cooling tower # 3 to reduce noise from falling water; the week of September 16, 2024, Constellation planted 150 black hill evergreen trees; the planted trees are located between the hot and cold canal and Dresden Road to mitigate noise beyond the hot/cold canal; the initial size of the trees is 4-5 ft tall and 1-2 ft wide, but are expected to grow to 40

+ ft and 20+ ft wide at a rate of 6-12 inches per year.

Constellation has a Noise Exceedance Mitigation Action Plan in place to implement actions to achieve and maintain compliance with state noise pollution regulations, which consists of:

o Constellation will conduct noise surveys/evaluations after the trees reach sufficient maturity to ensure compliance with applicable state noise pollution regulations; Based on the planting date, initial tree size, and the minimum expected growth rate of approximately 6 inches per year, Constellation estimates a 5-year growth period is recommended prior to performing noise surveys/evaluations; o When possible, operation of the cooling towers will be limited to daytime hours (7 am to 10 pm).

Constellation has not received a notice of violation or non-compliance from the Pollution Control Board with respect to noise levels because of operations at Dresden.

6)

NOI-02 Confirm that noise surveys were not conducted prior to installing the cooling towers in 1999, 2000, or 2003.

7)

NOI-03 Confirm that Constellation has not received any noise complaints since 2022 through October 2024 with respect to Dresden operations.

8)

GE-02 As described in the subsurface exploration report for the ISFSI expansion site, borings at the site included rock coring in five boreholes. A minimum of 25 ft of rock coring was performed at each of these borings. Boring logs describe the sandstone encountered as highly to moderately weathered and fractured. Boring logs describe the limestone encountered as moderately fractured. In some boreholes, the upper approximately 1 ft of sandstone was described as more weathered and fractured than the underlying sandstone rock. Please confirm the above summary is accurate.

9)

SW-01 During the audit, the NRC staff reviewed the 2023 surface water withdrawal data. Please confirm that the 2023 monthly surface withdrawal volumes in Table 1 and the 2023 annual surface water withdrawal volume in Table 2 are correct.

10)

SW-04 Please confirm that DNPS does not contribute to any of the water quality impairments listed in DNPS SLR ER Section 3.6.4.1 because DNPS does not discharge any constituents that could contribute to these impairments.

11)

SW-05 Please confirm the following statements regarding tritium concentrations measured in surface water via the DNPS REMP.

CEG is aware that Braidwood Station routinely discharges radioactive effluent, including tritium, into the Kankakee River upstream of DNPS.

CEG does not have a documented analysis to confirm that the routine radioactive effluent discharges from Braidwood are the source of tritium detections at DNPS REMP sampling location D-57, which is located upstream of DNPS on the Kankakee River.

12)

SW-06 Please confirm that discharge of tritiated groundwater from recovery well RW DN-100S to NPDES Outfall 002 is accounted for in the Annual Radioactive Effluent Release Reports (ARERRs) as a continuous release in the Liquid Effluents Continuous Mode tables for Units 2 and 3 (e.g., Tables 32 and 34 of the 2023 ARERR) and that quarters with no continuous release data indicate that there was no pumping from the recovery well and that measured CBG well tritium concentrations were below the detection limit.

13)

SW-08 Please confirm that stormwater tritium loading reported in the ARERRs was calculated based on the following procedures:

• The monthly volume of stormwater discharge was calculated as: precipitation depth (inches)

• assumed runoff fraction of 30%

• contributing surface area of 100,000 square feet. Months where tritium concentrations measured at the CBG Well were below the detection limit do not contribute to the annual stormwater volumes reported in the ARERRs. Precipitation depths were obtained from the Goose Lake weather station (https://gooselakeweather.com/).

• The monthly tritium loading was calculated by multiplying the monthly stormwater discharge volume by the measured tritium concentration at the CBG Well. Months when tritium concentrations were below the detection limit did not contribute to the tritium loading calculations.

During the audit, the NRC staff reviewed 2020 through 2023 tritium monitoring data for the CBG Well. Please confirm that the tritium concentrations for the CBG Well presented in the table below are correct.

14)

SW-11 Please confirm the following statements about surface water losses reported in Section 3.6.3.1 of the ER:

Estimated water losses reported in Section 3.6.3.1 of the ER were derived by calculating the difference between monthly diversions (closed cycle) or withdrawals (open cycle) and monthly discharge, as reported in Energy Information Administration (EIA) reports for DNPS.

Consumptive losses due to MDCT operation are based on hours of operation during a given time period (i.e., quarterly, or annually).

Estimated losses from cooling pond evaporation and seepage are based on differencing estimated MDCT losses from total losses.

Storm Sewer Manhole CBG Date uCi/mL Flag 1/29/2020 1.26E-06 2/26/2020 1.10E-06 4/14/2020 2.09E-06 5/20/2020 1.51E-06 6/17/2020 1.50E-06 7/21/2020 1.38E-06 8/19/2020 1.42E-06 9/29/2020 1.76E-06 10/20/2020 1.15E-06 11/11/2020 1.13E-06 12/8/2020 2.33E-06 1/19/2021 2.98E-06 2/23/2021 1.54E-06 3/10/2021 1.77E-06 4/13/2021 9.82E-07 5/6/2021 9.48E-07 6/9/2021 1.03E-06 7/21/2021 9.48E-07 8/10/2021 1.28E-06 9/22/2021 1.60E-06 10/19/2021 9.82E-07 11/10/2021 9.48E-07 12/8/2021 1.13E-06 1/14/2022 1.00E-06 2/8/2022 9.48E-07 3/16/2022 1.47E-06 4/18/2022 9.48E-07 5/23/2022 9.48E-07 6/7/2022 1.77E-06 7/26/2022 1.99E-06 8/16/2022 1.99E-06 9/26/2022 1.99E-06 10/24/2022 1.74E-06 11/15/2022 1.82E-06 12/5/2022 2.23E-06 1/18/2023 1.74E-06 2/8/2023 1.74E-06 3/15/2023 1.99E-06 4/17/2023 1.99E-06 6/21/2023 1.74E-06 7/18/2023 1.74E-06 8/15/2023 1.74E-06 9/21/2023 1.74E-06 10/18/2023 1.74E-06 11/14/2023 1.94E-06 12/5/2023 1.68E-06

Additionally, please confirm the following information provided in Dresdens annual air emission reports regarding operation of the 54 cooling tower cells and discussed during the water resources break out session:

In 2019, the total combined hours of operation were 90,057 hrs and the percent throughput for the months of March through May was 11.88%; June through August was 87.64%; and September through November was 0.48 percent.

In 2020, the total combined hours of operation were 64,440 hrs and the percent throughput for the months of June through August was 99.73% and for September through November 0.27%

In 2021, the total combined hours of operation were 70,164 hrs and the percent throughput for the months of June through August was 95.48% and for September through November was 4.52%

In 2022, the total combined hours of operation were 80,792 hrs and the percent throughput for the months of June through August was 71.77%, March through May was 4.91%, and September through November was 23.03%.

In 2023, the total combined hours of operation were 145,198 hrs the percent throughput for the months of March through May was 10.07%; June through August was 60.54%;

and September through November was 16.52%

Operation of the mechanical draft cooling towers is determined based on-site procedures, which include predictive modeling tools.

15)

SW-12 Please confirm that average monthly values of 2,538.6 and 45,024.4 million gallons per month for closed and open cycle operational modes, reported in Section 3.6.3.1, Page 3-103, correspond to surface water withdrawal volumes, not consumptive use.

16)

SW-14 Please confirm that reported "withdrawals" and "diversions" both describe the volume of surface water abstracted from the Kankakee/Des Plaines Rivers via the Unit 2/3 Intake Canal, and that "withdrawal" is used to describe abstractions during open-cycle mode while "diversion" is used to describe abstractions during close-cycle mode, per guidance from Energy Information Administration as described in the document located at:

https://www.eia.gov/survey/form/eia_923/instructions_schedule8d.pdf.

17)

SW-15 Please confirm the following statements about DNPS's SWPPP:

SWPPP inspections are conducted quarterly and at least once per year a SWPPP inspection is conducted when stormwater discharge is occurring.

The SWPPP will be revised if there is a change in construction operation or maintenance that may affect the discharge of significant quantities of pollutants, a quarterly or annual inspection identifies the need for an amendment, or a discharge violates a condition in the NPDES permit.

18)

SW-16 Please confirm the following statements about the SPCC plan for DNP:

Constellation is required to review and evaluate the SPCC plan at least once every five

years or immediately after a reportable quantity oil spill event.

Additionally, the SPCC plan will be amended within 6 months of a change in facility design, construction, operation, or maintenance occurs that may significantly affect the facilitys potential for offsite discharge of oil.

The SPCC plan outlines procedures for the assessment, reporting, and management for hazardous material spills.

The SPCC plan for DNPS covers procedures and controls for hazardous spill prevention, routine inspection procedures, and training programs for site personnel.

19)

SW-17 Please confirm that DNPS operates, inspects, and maintains the Dresden Nuclear Station Cooling Pond 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.

20)

GW-01 During the May 2023 annual cooling lake and circulating water canal examination, water surface elevations were reported to be about 522 ft in the cooling lake at the spillway, 506.25 ft in the hot canal, and 510.50 ft in the cold canal (both canal elevations at the Dresden Road bridge over the canals). Elevations in the piezometers located around the cooling lake ranged from 506.4 to 520.9 ft during the May 2023 examination. Please confirm this information is accurate.

21)

GW-04.

35 IAC 1010.200 (eff. May 2, 2008) requires licensees to report unpermitted releases of station-generated liquids that result in tritium concentrations of 200 pCi/L or more outside of the licensee-controlled area, which is the DNPS property boundary. Monitoring under the RGPP and the REMP are used to ensure this requirement is met. An internal procedure is also maintained for reporting unpermitted releases of radionuclides in accordance with 35 IAC 1010.200 requirements. Please confirm this information is accurate.

22)

TER-01 As discussed during the environmental audit and in response to information need TER-1, DPNS has four total cooling towers, three for the hot canal and one for the cold canal. All the cooling towers onsite are equipped with drift eliminators. Please confirm if the above summary is accurate.

23)

TER-03 As discussed during the environmental audit and in response to information need TER-3, the MET tower is 418 feet above ground level (AGL) with two sets of red lights on the structure. The top lights are solid, while lights in the middle are blinking. Please confirm if the above summary is accurate.

24)

TER-04 As discussed during the environmental audit and in response to information need TER-4, there are eight structures onsite that are 100 feet or more above ground level. Within the FAA database, there are three registered buildings/structures: Unit 1 Chimney Unit 2/3 Chimney and

MET Tower. The following are the eight structures 100 ft or above AGL and the corresponding heights:

MET tower 418 ft.

Unit 1 Chimney 300 ft.

Unit 2/3 Chimney 300ft Unit 2/3 Turbine Building Stack 159.38 ft.

Unit 1 Reactor Building 151 ft.

Unit 2/3 Reactor Building 141.54 ft.

Unit 2/3 Turbine Building 105.5 ft.

Heating boiler stack 100.5 ft.

Please confirm if the above summary is accurate.

25)

TER-06 As discussed during the environmental audit and in response to information need TER-06, the seven osprey platforms were installed by the Illinois and Kankakee rivers, sixteen blue bird nest boxes were installed by the Dresden cooling pond, and purple martin gourd house structures were relocated south of the training buildings in 2020. Please confirm if the above summary is accurate.

26)

TER-08 As discussed during the environmental audit and in response to information need TER-8, no bat mortalities occurred during the past five years (2018-2023). Please confirm if the above summary is accurate.

27)

TER-10 As discussed during the environmental audit and in response to information need TER-10, if injured or dead avian or wildlife species are found onsite, onsite environmental personnel and USFWS, the State Game Commission, or Department of Natural Resources conservation warden are notified, as applicable. Photos may be taken to help with identification. For injured wildlife or avian species, records are kept of pertinent details of the responding wildlife professional. For bird nests on equipment or structures, personnel will determine if nest is active and what species it belongs to. If the nest is non-active and non-protected species, the nest removal may occur and a deterrent may be placed. Please confirm if the above summary is accurate.

28)

TER-11 As discussed during the environmental audit and in response to information need TER-11, DNPS has osprey, purple martin, blue bird, bats, invasive species removal, living lands and water plantings, and pollinator management projects onsite. There is approximately 430 acres of grassland habitat onsite, which includes 12 acres dedicated to milkweed plantings and management, and 4 acres for native nut bearing hardwoods species restoration. Onsite there is approximately 7 acres of active invasive species prevention and monitoring, which includes mowing targeted invasive species and applying herbicide. Purple martins are using an average of 31 gourds for nesting since 2012 and bluebirds are using approximately 8-12 boxes since 2019. Please confirm if the above summary is accurate.

29)

TER-14 As discussed during the environmental audit and in response to information need TER-14, DNPS has invasive species present throughout the site from near the roadway to the old fields and grasslands to the canals. Management of invasive species includes mechanical removal, herbicide application, and burning. The management technique depends on the density of the invasive species population, species present, and environment. Please confirm if the above summary is accurate.

30)

AQU-02 Please confirm that bathymetric surveys of the intake canal are performed during every fueling outage, and on the discharge canals every four refueling outages. Please confirm that maintenance dredging would be required, and that the appropriate permitting would be acquired, if sediment accumulates to levels that reduce the Ultimate Heat Sink (UHS) volume below 1,800,000 gallons. Finally, please confirm that no dredging has occurred, to date, in the UHS.

31)

AQU-03 Please confirm that potential future construction and maintenance activities would follow CEG protocol to include CEGs Environmental Review Procedure, Environmental Screening Checklist, Environmental Evaluation Guidance, and the Excavation, Trenching, and Shoring Procedure.

32)

AQU-07 Please confirm that in 2018, the estimated impingement of the Kankakee River was over five times higher than those recorded in 2017. Additionally, please confirm that Constellation believes this increase correlates with a marked reduction in later summer river flow, compared to 2017, which likely led to higher concentrations of fish in localized areas, increasing their susceptibility to impingement and thus contributing to the elevated impingement results for 2018.

33)

AQU-08 Please confirm that no aquatic surveys or studies have been conducted regarding Outfall 004 related to thermal effluent and that a collective decision was made between coordinating agencies and CEG that surveys and/or studies were not necessary due to the short annual operation of Outfall 004 and no anticipated effects on aquatic resources. Additionally, please confirm the following regarding the Cooling Lake Siphon Line(s): 1) the siphon will not operate past March 15th each year to avoid interference with fish spawning, 2) the maximum amount of thermal effluent allowed is 0.5 billion BTU per hour, 3) if pond temperature is less than or equal to 47.5 degrees Fahrenheit (F) all three pipes may run, 4) if pond temperature is greater than 47.5 degrees F and less than or equal to 54.5 degree F only two pipes may run, 5) if pond temperature is greater than 54.5 degrees F and less than or equal to 77 degrees F only one pipe may run, 6) the diameter of each pipe is 3 feet and the pipes run along the bottom of the Kankakee river stretching across its width containing holes to release thermal effluent, 7) the siphons draw water from the cooling pond at a rate of 50 cubic feet per second per pipe, 8) that fishing nets are used to prevent cooling lake fish from travelling from the cooling lake, through

the siphon, to the Kankakee river, 9) the plant operates in closed cycle when the siphons are in operation; and 10.) the siphon lines create small vortexes in the cooling lake that can be heard at the road nearby (Cottage Rd).

34)

FPE-02 Please confirm that no surveys have been conducted to identify suitable roosting trees for listed bats, including the Indiana bat (Myotis sodalis), northern long-eared bat (Myotis septentrionalis),

and tricolored bat (Perimyotis subflavus). Additionally, please confirm that all forested portions of the site are considered potentially suitable habitat for the Indiana bat, northern long-eared bat, and tricolored bat.

35)

FPE-08 Please confirm that no targeted surveys have been conducted to identify the presence of the federally threatened eastern fringed prairie orchid (Platanthera leucophaea) and that neither the eastern fringed prairie orchid nor any species of violet have been observed on site, including during the 2018 invasive species survey.

36)

FPE-09 Please confirm that the DNPS Facilities Maintenance mows the following locations: 1) the grass parcels surrounding the training building; 2) the grass parcels between the contractor lot and Dresden Road; 3) the grass parcel in front of the administrative building; 4) the grass parcel in front of the Technical Support Center; 5) the grass parcel just east of the motorcycle pad; and 6) the grass parcel east of the contractor parking lot. Additionally, please confirm that if milkweed is identified on site, Facilities Maintenance are instructed to avoid mowing in the area immediately around the milkweed plant.

37)

FPE-10 Please confirm that there are no current known areas prone to erosion. Additionally, please confirm that if erosion does develop, several best management practices (BMPs) and control measures would be implemented from the Stormwater Pollution Prevention Plan (SWPPP) and Spill, Prevention, Control, and Countermeasure (SPCC) to include: 1) seeding; 2) mulching; 3) sodding; and 4) structural controls.

38)

FPE-14 Please confirm that bats have not been observed or detected during the emergence surveys conducted each spring, summer, and fall since the installation of the six bat boxes in the spring of 2022.

39)

FPE-15 Please confirm that herbicide application does not occur in any areas except the banks of the cooling lake, the banks of the water canals, and the portions of the DNPS site that are maintained by mowing. Please also confirm that all herbicide application is targeted and used for the purpose of invasive plant management.

40)

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:

Site preparation for Unit 1 began November 28, 1956 and construction was completed September 23, 1959 Unit 2 construction permit is dated December 29, 1965, and listed an estimated completion date from August 1, 1968 to June 1, 1969 For Unit 3, the Construction Permit Application was submitted February 10, 1966, and listed an estimated completion date between August 1, 1969, and June 1, 1970.

41)

HCR-02 As discussed during the environmental audits Historic and Cultural Resources breakout session and in response to information need HCR-4, confirm that the acreage of the built facility area within the Extended Area Boundary (EAB) is approximately 343 acres. The only facilities outside of the EAB are the meteorology tower and the cooling canals/lakes, which date back to DNPS' original construction phases ranging from the late 1950s to 1970.

42)

HCR-03 As discussed during the environmental audits Historic and Cultural Resources breakout session and in response to information need HCR-3, confirm the following:

The Pokagon Band of Potawatomi Indian lands are approximately 34 miles outside of the DNPS 50-mile radius.

After NRCs acceptance of CEGs ER, the Prairie Band Potawatomi Nation received federal recognition, becoming the first federally recognized Tribe in Illinois. Consistent with its earlier engagement with Federally recognized Tribes, CEG sent a letter to the Prairie Band Potawatomi Nation in February 2023 informing them about the SLR. To date, CEG has not received a response from the Tribe.

43)

HCR-04 During the environmental audits Historic and Cultural Resources breakout session and in the follow-up response to information need HCR-4, confirm that for the construction of the independent spent fuel storage installation (ISFSI) expansion project, CEG staff implemented its procedures and determined that monitoring by archaeologists or Tribal monitors was not required because the area is considered to be previously disturbed from construction of DNPS.

Confirm that CEG notified the IL SHPO by letter dated February 6, 2020, about the expansion but did not receive a reply.

44)

HCR-05 As discussed during the environmental audits Historic and Cultural Resources breakout session and in response to information need HCR-5, confirm the following information:

CEG owns the easement where two potentially National Register eligible archaeological sites are located. Commonwealth Edison (ComEd) owns, operates, and maintains the transmission lines on CEG property.

Should ComEd need to perform ground disturbing activities within the DNPS transmission line corridor, ComEd would notify CEG. CEG would then follow existing protocols and procedures to engage with ComEd and outline the responsibilities and work activities prior to any work being performed. Any ground disturbing or maintenance activities conducted onsite would also follow CEGs environmental protocols and procedures for identifying and protecting historic and cultural resources.

45)

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

No additional archaeological or architectural surveys were completed in support of the SLR.

CEG has not received any responses from the notification letters sent to federally recognized Tribes identifying any Traditional Cultural Properties within the APE.

46)

HCR-09 As discussed during the environmental audits Historic and Cultural Resources breakout session and in response to information need HCR-9, confirm that if erosion is observed, CEG would follow their protocol as identified in HCR-11.

47)

HCR-10 As discussed during the environmental audits Historic and Cultural Resources breakout session and in response to information need HCR-10, confirm that Exelon/CEG cultural resources information is kept within DNPS electronic data management system. If CEG is performing excavations, their procedure Excavation, Trenching, and Shoring (SA-AA-117) instructs CEG staff to review previously performed cultural, historical and paleontological resources and previous surveys to make sure excavation does not disturb identified resources. Prior to starting a project that requires land disturbance in a previously undisturbed area, CEG staff would contact the Illinois State Historic Preservation Office to perform a review, regardless of whether or not a previous cultural resources survey has been performed in the area.

48)

HCR-11 As discussed during the environmental audits Historic and Cultural Resources breakout session and in response to information need HCR-11, confirm that CEG does not have a specific inadvertent discovery plan for human remains. Their procedure Excavation, Trenching, and Shoring (SA-AA-117) includes definitions on cultural, historical and paleontological resources. If human remains are discovered, work would be stopped immediately and site security would be notified, who would then contact local law enforcement. Law enforcement would report the discovery to the county coroner. The coroner would determine if further investigation were needed. If the coroner determines that the remains are over 100 years old, the Illinois Historic Preservation Agency (IHPA) would take over jurisdiction. If the remains are believed to be less

than 100 years old, the coroner would maintain jurisdiction.

In Illinois, the Human Skeletal Remains Protection Act protects burials, burial markers (including Native American mounds), and burial artifacts from disturbance, including vandalism, defacement, destruction, sale, exchange, excavation, or removal. CEG commits to uphold state law and cooperate in investigations and subsequent recommended actions.

49)

HCR-12 As discussed during the environmental audits Historic and Cultural Resources breakout session and in response to information need HCR-12, confirm that there are no planned ground-disturbing approved projects for DNPS at this time.

50)

HCR-13 As discussed during the environmental audits Historic and Cultural Resources breakout session and in response to information need HCR-13, confirm that 150 trees were planted along the east side of the hot canal in September 2024. Prior to engaging in ground disturbing activities, the project went through CEGs environmental screening process. No cultural resource surveys were conducted prior to the plantings, as the area is considered previously disturbed associated with construction of the hot canal. The tree planting location is over 1,750 meters from the Illinois and Michigan Canal NRHP District and over 1,800 meters southwest of the Dresden Island Lock and Dam NRHP District. CEG considers that the trees would not visually impact the two Districts owing to topography and existing land cover.

Additionally, confirm that no further tree plantings are planned at this time.

51)

HCR-16 As discussed during the environmental audits Historic and Cultural Resources breakout session and in response to information need HCR-16, confirm that CEGs Excavation, Trenching, and Shoring (SA-AA-117) outlines work practices for excavation, trenching and shoring and includes CEGs Excavation Permit. Section 3.8.3 of the procedure states that if cultural resources are identified during excavation, then Environmental Personnel COORDINATE actions involving the salvage and/or disposition of the resources, and RELEASE the excavation site to resume work once these activities are completed. Section 4.1.2 states that if work is being done in an area previously surveyed, requires them to review the previous survey to make sure excavation does not disturb identified resources (CM-7).

52)

HCR-17 As discussed during the environmental audits Historic and Cultural Resources breakout session and in response to information need HCR-17, confirm that CEGs procedure EN-AA-103-0001, Rev 009, Environmental Evaluations, outlines the requirements for Cultural, Historic and Paleontological (CHP) resource evaluation.

53)

SOC-01 As discussed during the environmental audit and in response to information need SOC-01, please provide an update to the ERs Table 3.9-2 to include 2023 payments.

54)

SOC-02 As discussed during the environmental audit and in response to information need SOC-02, please confirm annual grant payments of $3,800,000 ($1.9M per reactor) to the IEMAOHS from 2021-2023.

55)

HH-01 As discussed during the environmental audit and in response to information need HH-01, please confirm CEG has not observed algae blooms in the area surrounding DNPS discharge to the Illinois river encountered elevated levels of fecal coliform or been notified by any local state or federal agencies of algae blooms or waterborne diseases in relation to DNPS. Also confirm that temperatures are monitored for triggering cooling tower operation but not within the cooling lake and that the entire cooling lake perimeter is fenced to deny access to members of the public.

56)

HH-02 As discussed during the environmental audit and in response to information need HH-02, please confirm there have been no OSHA recordable injuries since the end of 2022 and the submission of the ER.

57)

HH-03 As discussed during the environmental audit and in response to information need HH-03, please confirm that there has been a lack of public health concerns in the receiving waters of DNPS by the IDPH and that CEG and the IEPA have an ongoing relationship in regards to NPDES discharges.

58)

HH-04 Based on information discussed in the HH-4 audit regarding Constellations corporate electrical safety program procedures, confirm that Constellation ensures that Dresden's in-scope transmission lines satisfy NESC standards through adherence to station electrical safety procedures.

59)

HH-05 As discussed during the environmental audit and in response to information need HH-05, please confirm that CEGs fleet safety procedure complies with the Illinois Administrative Code Title 83 Section 305.20 that a) apply to electric utilities and those telecommunications carriers subject to Section 8-505 of the Public Utilities Act [220 ILCS 5/8-505] and b), which follows portions of the 2017 edition of the National Electrical Safety Code namely:

1. Section 2, Definitions of Special Terms;

2. Section 9, Grounding Methods of Electric Supply and Communications Facilities;

3. Part 2, Sections 20 to 27, Safety Rules for the Installation and Maintenance of Overhead Electric Supply and Communication Lines; and

4. Part 3, Sections 30 to 39, Safety Rules for the Installation and Maintenance of

Underground Electric Supply and Communication Lines.

60)

HH-06 N/A - Documents were provided in the electronic reading room for staff inspection.

61)

EJ-01 As discussed during the environmental audit and in response to information need EJ-01, please confirm that local communities participated in a survey conducted under the Consent-Based Siting Initiative and that no concerns were uncovered about the continued operation of DPNS.

62)

WM-01 The ER Section 2.2.6.1 discusses radioactive liquid waste management systems. As discussed during the audit, please confirm the following:

a) The ER Section 2.2.6.1 states that the processed wastewater may be discharged to the river through the discharge canal. As discussed during the audit, the plant has not had a routine (batch or continuous) radioactive liquid effluent discharge since 2009. The plant may discharge if needed, but since 2009, instead of being discharged as effluent, processed water from the equipment drain system and floor drain system has been recycled into the condensate system.

b) The ER Section 2.2.6.1 describes a maximum recycle system; however, this system is retired. Instead, the water from the equipment drain system is routed to a system referred to as advanced liquid processing (APL). After being processed by the APL, water is sampled and routed back to the Condensate Storage Tanks (CSTs) to be either discharged (if needed) or recycled into the condensate system.

c) The ER Section 2.2.6.1 describes portable waste treatment systems. As discussed during the audit, the portable waste treatment systems are only used when temporary waste treatment systems are needed in specific locations and are not part of the routine system.

63)

WM-02 Section 2.2.6.5 notes that Dresden provides onsite storage of mixed waste and Section 2.2.7 discusses hazardous and universal wastes. Please confirm the following:

a) There are no other wastes, besides mixed waste, stored in the mixed waste storage location.

b) There are no proposed upgrades or changes planned for the hazardous or mixed waste program during the SLR term.

c) The increased volume of nonhazardous waste disposed of in 2020 compared to other years in the period of 2018-2022 is due to housekeeping activities in preparation for potential decommissioning at that time.

64)

WM-03 Section 2.2.6.3 discusses the Radioactive Solid Waste Management Systems. As discussed during the audit, please confirm the following:

a) There are no proposed upgrades or changes to the solid LLW management program during the SLR term.

b) DNPS does not currently store any GTCC waste onsite.

c) There is sufficient storage space for GTCC waste should it need to be stored.

65)

WM-04 DNPS 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 2018-2023, there were no reportable releases that have triggered this notification requirement. As discussed during the audit, please confirm there have been no reportable releases to date which would trigger notification requirement to date since the ER submittal.

66)

WM-05 (Abnormal radioactive releases - TBD - depending on the licenses revised portal information)

67)

WM-06 As discussed during the audit, please confirm there have been no inadvertent releases or spills of nonradioactive contaminants to date that would trigger a notification requirement since the DNPS SLR ER submittal.

68)

WM-07 As discussed during the additional audit breakout session (on December 3, 2024), please confirm the following:

a) Although Section 3.6.4.2 of the DNPS SLR ER indicates that 6,000 cubic meters of soil were disposed of onsite, the actual volume of soil totaled approximately 3,820 cubic meters.

b) No sewage treatment drying bed waste was placed in this disposal area; therefore, no permits from the State of Illinois were required.

c) There are no plans to add materials in this disposal area.

d) Any material remaining from the disposal site at the time of license termination will be accounted for in demonstrating compliance with the criteria for decommissioning in 10 CFR 50.82 and 10 CFR part 20, subpart E.

69)

SNF-01 The ER Section 2.2.6.4 states that The station has two separate ISFSIs. The East ISFSI is comprised of two sections and has space for 10 additional casks. The West ISFSI is one pad and has space for 13 additional casks. As of November 2023, DNPS has completed construction on an expansion of the West ISFSI that will provide adequate storage to operate through the subsequent period of extended operation (SPEO) for Units 2 and 3. As discussed during the audit please confirm the following:

a) There are three ISFSIs on the site. The East ISFSI, the West ISFSI, and the South ISFSI (which is referred to as the West ISFSI expansion in the ER).

b) The West ISFSI second pad construction has been completed.

c) The South ISFSI has one completed pad that can accommodate fuel up until approximately 2031. Land immediately to the north and adjacent to the South pad is planned for future ISFSI expansion. This additional pad in the South ISFSI would have enough capacity to accommodate dry storage needs, but the pools would still be necessary for spent fuel storage accounting for this additional expansion that is planned. If further expansion is deemed necessary, there are locations within the site on previously disturbed land that could be available.

70)

GHG-CC-01 Confirm that the highest employee count from 2018 through 2022 was 800 employees and that the estimated greenhouse gas emissions from worker vehicles are 3,168 metric tons of carbon dioxide equivalent.

71)

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 circuit breakers.

Process CO2 is used in the emergency fire suppression system and main generator hydrogen purging during outages.

Constellation has procedures for performing of main condenser tube leak testing, control room tracer gas testing, and maintenance and inspections of the SF6 circuit breakers;.

Emissions calculations are based on emission factors from the Environmental Protection Agencys 2023 emission factors for greenhouse gas inventories table and hours of operation for combustion sources, sulfur hexafluoride usage and/or leaks, carbon dioxide gas usage, and fugitive emissions from refrigerants.

For 2023, direct emissions are 2,662 metric tons of carbon dioxide equivalents and 53,594 metric tons of carbon dioxide equivalents for purchased electricity.

For direct greenhouse gas emissions, the relative percentage of each source accounted are as follows:

2023 2022 2021 2020 2019 2018 Station Combustion Sources 98.05 90.85 99.21 89.78 75.99 89.75 SF6 0

0 0

5.59 21.02 0

CO2 0.21 0.71 0.14 0.24 0.33 0

Hydrofluorocarbons/perfluorocarbons (HFCs/PCFs) refrigerants 0

6.04 0

1.98 2.16 0

Ozone Depleting Chemicals Refrigerants 1.74 2.4 0.65 2.4 0.5 10.25

REQUESTS FOR ADDITIONAL INFORMATION (RAI)

72)

RAI GEN-01 REQUIREMENT:

ISSUE:

REQUEST:

73)

RAI NOI-01 REQUIREMENT: The regulations at 10 CFR 51.53(c)(3)(Q)(iv) states that the environmental report must contain any new and significant information regarding the environmental impacts of license renewal of which the applicant is aware.

ISSUE: The environmental report identified that the cooling towers are the primary contributing noise source from operations of Dresden to nearby recreation and residential receptors. Section 3.4 of the environmental report states that in 2017, DNPS completed a two-phase noise evaluation which found that cooling tower noise levels were 58 dBA at the nearest residence and exceeded Illinois nighttime limits of 51 dBA for residential receivers. The environmental report also identifies that Constellation will support the planting of 150 evergreen trees to mitigate noise to offsite residences. Section 4.3.4 of the environmental report provides concludes that the impacts from subsequent license renewal term would be SMALL. Section 4.3.4 of the environmental report, however, does not address the reduction in sound levels at the nearest resident during the subsequent license period anticipated as a result of the implemented mitigation measures. In response to information need NOI-1, Constellation stated that they have a noise exceedance mitigation action plan for Dresden. The action plan includes conducting noise measurements when the trees reach sufficient maturity, which is estimated to be 5 years from the planting date (September 2024), to ensure compliance with state noise pollution regulations. Additionally, documents provided in response to information need SW-5 identify that there are three siphon lines that draw water from the Dresden cooling lake to the Kankakee River and create small vortexes in the cooling lake that can sometimes be heard at the road. However, the ER did not identify this as a noise source.

REQUEST:

A. Provide a discussion that estimates quantitatively the sound level(s) at the nearest resident during the subsequent license renewal period that considers the planted trees.

As part of the discussion include a basis and assumptions for the estimate(s) provided.

B. Discuss if Constellation plans to update the noise exceedance mitigation action plan for Dresden, as needed, to ensure compliance with state noise pollution regulations after noise measurements are completed.

C. Provide a copy of the 2017 two-phase noise evaluation.

D. With respect to the vortexes that form in the cooling lake when the siphon line is in use, are sound levels at the road or residents located across the three siphon pipes available? If so, please provide this information.

74)

RAI SW-02 REQUIREMENT: 10 CFR 51.45(b) and 51.53(c)(2) require the that ER include a description of the affected environment.

ISSUE: The NRC staff is preparing a site-specific EIS that considers the site-specific environmental impacts of subsequent license renewal for DNPS. As part of preparing the site-specific EIS, the staff must be able to review the recent intake and discharge water temperature data as it is relevant to assessing surface water impacts.

REQUEST: Provide plots of average monthly intake and discharge temperatures over the 2018-2023 period.

75)

RAI-SW-03 REQUIREMENT: 10 CFR 51.45(b) and 51.53(c)(2) require that the ER include a description of the affected environment.

ISSUE: The NRC staff is preparing a site-specific EIS that considers the site-specific environmental impacts of subsequent license renewal for DNPS. As part of preparing the site-specific EIS, the staff must provide a description of the cooling water intake system pathway.

The ER does not include a figure that illustrates the cooling water intake system pathway.

REQUEST: Provide a figure that illustrates the cooling water intake system pathway as described in the ER and environmental audit.

76)

RAI TER-05 REQUIREMENT: 10 CFR 52.45(d) require the environmental report to include discussion of the status of compliance with applicable environmental quality standards imposed by Federal, State, regional and local agencies. In addition, 10 CFR 51.53(Q)(iv) require that the environmental report must contain any new and significant information regarding environmental impacts of license renewal of which the applicant is aware.

ISSUE: The NRC staff is preparing an EIS that considers the environmental impacts of subsequent license renewal for Dresden. As part of the preparing the EIS, the staff must consider whether the has been any new information related to terrestrial resources. During the October 2024 environmental audit and Terrestrial Resources breakout session, Constellation discussed avian injuries and mortalities onsite for the past 10 years.

REQUEST: Please provide a summary of bird mortalities or injuries (species, date, cause if known, associated structures or buildings, if any; final outcome) in chronological order from 2013-2024. If there are no bird mortalities or injuries observed at the DNPS site in a given a year, include a note in the summary or provide a statement regarding those years.

77)

RAI AQU-06 REQUIREMENT: The NRCs regulation at 10 CFR 51.53(c)(3)(ii)(B) requires that if the

applicants plant utilizes a once-through cooling or cooling pond water intake and discharge system, the applicant shall provide a copy of current Clean Water Act 316(b) Best Technology Available determinations and, if applicable, a 316(a) variance in accordance with 40 CFR part 125, or equivalent State permits and supporting documentation. If the applicant cannot provide these documents, it shall assess the impact of the proposed action on fish and shellfish resources resulting from impingement mortality and entrainment and thermal discharges.

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.

ISSUE: Because the Illinois Environmental Protection Agency has not yet made Clean Water Act 316(b) Best Technology Available determinations for Dresden, the NRC staff requires additional information in order to assess the impact of the proposed action on fish and shellfish resources resulting from impingement mortality and entrainment. The NRC staff also requires additional information concerning Dresdens Clean Water Act 316(a) variance in order to assess the impacts of thermal discharges on aquatic organisms.

REQUEST: Please provide copies of the following document(s):

1. 1991-2014 Long term Aquatic Monitoring Program

a. EA Engineering, Science, and Technology, Inc., PBC (EA). 2001. Dresden Nuclear Station Aquatic Monitoring 2000, RM 270.5-273.0. Report by EA to Exelon Nuclear Company, Dresden Nuclear Station, Morris, IL.

b. EA Engineering, Science, and Technology, Inc., PBC (EA). 2002. Dresden Nuclear Station Aquatic Monitoring 2001, RM 270.5-273.0. Report by EA to Exelon Nuclear Company, Dresden Nuclear Station, Morris, IL.

c. EA Engineering, Science, and Technology, Inc., PBC (EA). 2003. Dresden Nuclear Station Aquatic Monitoring 2002, RM 270.5-273.0. Report by EA to Exelon Nuclear Company, Dresden Nuclear Station, Morris, IL.

d. EA Engineering, Science, and Technology, Inc., PBC (EA). 2004. Dresden Nuclear Station Aquatic Monitoring 2003, RM 270.5-273.0. Report by EA to Exelon Nuclear Company, Dresden Nuclear Station, Morris, IL.

e. EA Engineering, Science, and Technology, Inc., PBC (EA). 2005. Dresden Nuclear Station Aquatic Monitoring 2004, RM 270.5-273.0. Report by EA to Exelon Nuclear Company, Dresden Nuclear Station, Morris, IL.

f.

EA Engineering, Science, and Technology, Inc., PBC (EA). 2006. Dresden Nuclear Station Aquatic Monitoring 2005, RM 270.5-273.0. Report by EA to Exelon Nuclear Company, Dresden Nuclear Station, Morris, IL.

g. EA Engineering, Science, and Technology, Inc., PBC (EA). 2007. Dresden Nuclear Station Aquatic Monitoring 2006, RM 270.5-273.0. Report by EA to Exelon Nuclear Company, Dresden Nuclear Station, Morris, IL.

h. EA Engineering, Science, and Technology, Inc., PBC (EA). 2008. Dresden Nuclear Station Aquatic Monitoring 2007, RM 270.5-273.0. Report by EA to Exelon Nuclear Company, Dresden Nuclear Station, Morris, IL.

i.

EA Engineering, Science, and Technology, Inc., PBC (EA). 2010. Dresden Nuclear Station Aquatic Monitoring 2008, RM 270.5-273.0. Report by EA to Exelon Nuclear Company, Dresden Nuclear Station, Morris, IL.

j.

EA Engineering, Science, and Technology, Inc., PBC (EA). 2012. Dresden Nuclear Station Aquatic Monitoring 2011, RM 270.5-273.0. Report by EA to Exelon Nuclear Company, Dresden Nuclear Station, Morris, IL.

k. EA Engineering, Science, and Technology, Inc., PBC (EA). 2014. Dresden Nuclear Station Aquatic Monitoring 2013, RM 270.5-273.0. Report by EA to Exelon Nuclear Company, Dresden Nuclear Station, Morris, IL.

l.

EA Engineering, Science, and Technology, Inc., PBC (EA). 2015. Dresden Nuclear Station Aquatic Monitoring 2014, RM 270.5-273.0. Report by EA to Exelon Nuclear Company, Dresden Nuclear Station, Morris, IL.

2. Impingement and Entrainment Studies

a. EA Engineering, Science, and Technology, Inc., PBC (EA). 2015. Freshwater Mussel Survey in the Illinois River near the Dresden Nuclear Station (RM 271-272.5). Report by EA to Exelon Nuclear Company, Warrenville, IL.

b. EA Engineering, Science, and Technology, Inc., PBC (EA). 2007.

Impingement Mortality Characterization Study (2005-2007) Dresden Station.

Final Draft. November 2007. Report by EA to Exelon Nuclear Company, Warrenville, IL.

c. EA Engineering, Science, and Technology, Inc., PBC (EA). 2007.

Entrainment Characterization Study (2005-2007) Dresden Station. Final Draft. October 2007. Report by EA to Exelon Nuclear Company, Warrenville, IL.

d. EA Engineering, Science, and Technology, Inc., PBC (EA). 2019.

Impingement Characterization Report for Dresden Nuclear Power Station.

Report by EA to Exelon Generation Company, Dresden Nuclear Station, Morris, IL.

e. EA Engineering, Science, and Technology, Inc., PBC (EA). 2019.

Entrainment Characterization Report for Dresden Nuclear Power Station.

Report by EA to Exelon Generation company, Dresden Nuclear Station, Morris, IL.

3. NPDES/316(b) Demonstrations

a. AECOM. 2016. 40 CFR 122.21(r)(2-8) NPDES Application Requirements for Facilities with Cooling Water Intake Structures Exelon Generation Company, LLC, Dresden Nuclear Power Station, Morris, Illinois. May.

b. AECOM. 2019. 40 CFR 122.21(r)(10) NPDES Application Requirements for Facilities with Cooling Water Intake Structures. Report by AECOM to Exelon Generation Company, LLC, Dresden Generating Station, Morris, IL.

c. AECOM. 2019. 316(b) Executive Summary. Report by AECOM to Exelon Generating Company, LLC, Dresden Generating Station, Morris, IL.

4. Thermal Effluent Studies

a. Dresden Nuclear Station (DNS). 2015. Draft Dresden Nuclear Station 316(a)

Demonstration [including all appendices]. May 29, 2015.

78)

RAI AQU-08 REQUIREMENT: The NRCs regulation at 10 CFR 51.53(c)(3)(ii)(B) requires that if the applicants plant utilizes a once-through cooling or cooling pond water intake and discharge system, the applicant shall provide a copy if applicable, a 316(a) variance in accordance with 40 CFR Part 125, or equivalent State permits and supporting documentation. If the applicant cannot provide these documents, it shall assess the impacts of the proposed action on fish and shellfish resources resulting fromthermal discharges.

Additionally, 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: As of 13 December 2024, the U.S. Fish and Wildlife Service proposed critical habitat for the Sheepnose mussel in the Kankakee River. Outfall 004 discharges Cooling Lake thermal effluent into the Kankakee River for up to two, 14-day periods annually. The CWA 316(a) variance is only applicable to the primary discharge of DNPS, and not Outfall 004. With the new proposed designation of critical habitat in the Kankakee River, and the potential for mixing of thermal effluent into the Kankakee River, the NRC staff is seeking additional information for their review.

REQUEST: Please provide copies of the following studies/document(s):

5. Outfall 004 Siphon Run Reports

6. Will County Emergency Management Agency (WCEMA). 2024. Will County Kankakee River Ice Management Project Season Operating Report 2024. Report by WCEMA to Constellation. Will County, IL.

7. Constellation, LLC, (CEG). 2023. Siphon Line Report Dresden Nuclear Generating Station NPDES Permit Number IL0002224 PMLTR 23-0005. Report by Will County Emergency Management Agency for CEG to Illinois Environmental Protection Agency. Dresden Nuclear Station, Morris, IL.

8. Constellation, LLC. (CEG). 2022. Siphon Line Report Dresden Nuclear Generating Station NPDES Permit Number IL0002224 PMLTR 22-0008. Report by Will County Emergency Management Agency for CEG to Illinois Environmental Protection Agency. Dresden Nuclear Station, Morris, IL.

9. Constellation, LLC, (CEG). 2021. Siphon Line Report Dresden Nuclear Generating Station NPDES Permit Number IL0002224 PMLTR 21-0010. Report by Will County Emergency Management Agency for CEG to Illinois Environmental Protection Agency. Dresden Nuclear Station, Morris, IL.

10. Constellation, LLC, (CEG). 2020. Siphon Line Report Dresden Nuclear Generating Station NPDES Permit Number IL0002224 PMLTR 20-0008. Report by Will County Emergency Management Agency for CEG to Illinois Environmental Protection Agency. Dresden Nuclear Station, Morris, IL.

11. Constellation, LLC, (CEG). 2019. Siphon Line Report Dresden Nuclear Generating Station NPDES Permit Number IL0002224 PMLTR 19-0010. Report by Will County Emergency Management Agency for CEG to Illinois Environmental Protection Agency. Dresden Nuclear Station, Morris, IL.

12. Constellation, LLC, (CEG). 2018. Siphon Line Report Dresden Nuclear Generating Station NPDES Permit Number IL0002224 PMLTR 18-0010. Report by Will County Emergency Management Agency for CEG to Illinois Environmental Protection Agency. Dresden Nuclear Station, Morris, IL.

13. Constellation, LLC, (CEG). 2017. Siphon Line Report Dresden Nuclear Generating Station NPDES Permit Number IL0002224 PMLTR 17-0014. Report by Will County Emergency Management Agency for CEG to Illinois Environmental Protection Agency. Dresden Nuclear Station, Morris, IL.

14. Constellation, LLC, (CEG). 2016. Siphon Line Report Dresden Nuclear Generating Station NPDES Permit Number IL0002224 PMLTR 16-0020. Report by Will County Emergency Management Agency for CEG to Illinois Environmental Protection Agency. Dresden Nuclear Station, Morris, IL.

15. Constellation, LLC, (CEG). 2015. Siphon Line Report Dresden Nuclear Generating Station NPDES Permit Number IL0002224 PMLTR 15-0031. Report by Will County Emergency Management Agency for CEG to Illinois Environmental Protection Agency. Dresden Nuclear Station, Morris, IL.

16. Constellation, LLC, (CEG). 2014. Siphon Line Report Dresden Nuclear Generating Station NPDES Permit Number IL0002224 PMLTR 14-0043. Report by Will County Emergency Management Agency for CEG to Illinois Environmental Protection Agency. Dresden Nuclear Station, Morris, IL.

17. US Army Corps of Engineers Initial Study on Siphon Lines

18. U.S. Army Corps of Engineers (USACE). 1993. River Ice Management Project Operations and Maintenance Manual. Will County Office of Emergency Services, Will County, IL.

79)

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. 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 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 Dresden subsequent license renewal.

REQUEST: Please describe the ESA action area for the proposed Dresden subsequent license renewal.

80)

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 released an updated Northern Long-eared Bat and Tricolored Bat Range-Wide Determination Key (DKey) on October 23, 2024. 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 Dresden subsequent license renewal on the northern long-eared and tricolored bats.

REQUEST: Please provide a copy of the responses to the latest version of the Northern Long-eared Bat and Tricolored Bat Range-Wide DKey that was released on November 7, 2024 for the continued operations of Dresden during the proposed license renewal term. The Northern Long-eared Bat and Tricolored Bat Range-Wide 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-and-tricolored-bat-range-wide-determination-key.

81)

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 ESA on September 14, 2022 (87 FR 56381). This species range includes Grundy County and may occur in the action area. The ER does not provide an analysis of the potential impacts on this species.

REQUEST: Please provide an analysis of the potential impacts of the proposed license renewal on the tricolored bat. 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 CEG may identify.

82)

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 ESA and to designate critical habitat for this species on August 22, 2023 (88 FR 57223). This species range includes Grundy County and may occur in the action area. The ER does not provide an analysis of the potential impacts on this species.

REQUEST: Please discuss whether any aquatic surveys 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 CEG may identify.

83)

RAI FPE-06 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 U.S. Fish and Wildlife Services Information for Planning and Conservation database (https://ipac.ecosphere.fws.gov/) 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 (Grus americanus). 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 CEG may identify.

84)

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. 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 ESA on August 6, 2024 (89 FR 63888). This species range includes Will and Grundy counties. The ER does not address this species.

REQUEST: Please provide an analysis of the potential impacts of the proposed license renewal

on the Western regal fritillary (Argynnis idalia occidentalis). 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 CEG may identify.

85)

RAI HCR-07 REQUIREMENT: Section 106 of the National Historic Preservation Act (NHPA [54 USC

§306108]) directs Federal agencies to take into account the effect of the undertaking on any district, site, building, structure, or object that is included in or eligible for the National Register of Historic Places within the area of potential effect (APE). NHPAs implementing regulations 36 CFR § 800.4(1) directs Federal agencies to identify historic properties, including background research, consultation, oral history interviews, sample field investigation, and field survey. In 36 CFR § 800.1(c), federal agencies must complete the Section 106 process prior to the issuance of any license. NRC regulations at 10 CFR 51.53(c)(3)(ii)(K) state that NRC may request that applicants provide information to the NRC to identify any potentially affected historic and cultural resources and historic properties to support the environmental review and associated NHPA Section 106 consultation.

ISSUE: ER Section 3.8.3 mentions that the structures within the DNPS property have not been surveyed, although many of them are over 50 years old. The buildings were not evaluated for potential listing on the National Register of Historic Places as required under 36 CFR 800.4.

NRC staff, in consultation with the IL SHPO, has determined that an architectural survey is necessary.

REQUEST: The NRC is requesting that CEG conduct an architectural survey of above-ground resources on the DNPS site (i.e., area of potential effect) 45 years or older that meet the standards set forth in 36 CFR 800.4(b), identify historic properties, and apply the National Register criteria as required in 36 CFR 800.4(c). Preliminary determination of eligibility for the site and/or facilities would need to be known prior to the publication of NRCs Final SEIS, currently planned for October 2025 publication, to support NRCs determination of effects from the proposed undertaking. Per 36 CFR 800.1(c), the NRC must complete the NHPA Section 106 process prior to the issuance of any license. The NRC requests that CEG provide an estimated timeframe for when this survey could be completed. If a preliminary determination is not completed by publication of the Final SEIS, a Section 106 agreement document or equivalent would need to be executed.

86)

RAI GHG-CC-04 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.

ISSUE: Figure 3.6-4 and Figure 3.6-5 of the ER present average monthly discharge temperatures and average monthly intake temperatures for 2018-2022. However, the ER does not discuss if a warming trend has been observed at these locations on the long-term available period of record.

REQUEST: As provided in response to audit information need GHG-CC-4, provide time series figures of:

monthly average intake cooling water temperatures; average monthly seasonal intake temperatures; monthly average of discharge water temperatures; and average monthly seasonal discharge temperatures.

As part of the response, explain:

the gaps in data for the intake temperatures in 2015 and 2021, and why discharge temperatures for 2010 through 2013 are higher than discharge temperatures for 2014 through 2023 and identify the location of temperature probes used to measure discharge temperatures.

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