TXX-2402, (CPNPP) - 2023 Annual Radiological Effluents Release Report

(CPNPP) - 2023 Annual Radiological Effluents Release Report

ML24109A196
Person / Time
Site:	Comanche Peak
Issue date:	04/18/2024
From:	Hicks J Vistra Operations Company
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
TXX-24023, CP-202400106
Download: ML24109A196 (1)

Text

Comanche Peak Nuclear Power Plant

Manager, P.O Box 1002 6322 North FM 56 Glen Rose, TX 76043

CP-202400106 TXX-24023 April, 2024

U.S. Nuclear Regulatory Commission Ref 10CFR 50.36(a)

ATTN: Document Control Desk TS 5.6.3 Washington, DC 20555-0001

Subject:

Comanche Peak Nuclear Power Plant (CPNPP)

Docket Nos. 50-445 and 50-446 2023 Annual Radiological Effluents Release Report

Dear Sir or Madam:

Vistra Operations Company LLC (Vistra OpCo) hereby submits the Comanche Peak Nuclear Power Plant (CPNPP) 2023 Annual Radioa ctive Effluents Release Report. The enclosed report is provided pu rsuant to 10 CFR 50.36a and CPNPP Technical Specification 5.6.3. The report covers the period from January 1, 2023 to December 31, 2023.

This letter contains no new regulatory commitments for CPNPP Unit 1 and Unit 2.

If you have any questions regarding this submittal, please contact Kassie Mandrell at (254) 897-6987 or Kassie.Mandrell@luminant.com.

Sincerely,

Enclosure:

CPNPP 2023 Annual Radioactive Effluent Release Report

c (email) - John Monninger, Region IV [John.Monninger@nrc.gov]

Samson Lee, NRR [Samson.Lee@nrc.gov]

John Ellegood, Senior Resident Inspector, CPNPP [John.Ellegood@nrc.gov]

Henry Strittmatter, Resident Inspector, CPNPP [Henry.Strittmatter@nrc.gov]

TXX-24023 Enclosure Page 1 of 57

2023 A NNUAL RA DIOLOGIC AL EFFLUENTS RELEASE REPORT

January 1, 2023 - December 31, 2023

Preparer: Donald E. Rebstock Date: 3/18/2024 Reviewer: Garrick Kinchen Date: 3/20/2024 Approver: Kerry Cooper Date: 3/20/2024 Chemistry Manager TXX-24023 Enclosure Page 2 of 57

TABLE OF CONTENTS

ACRONYMS AND ABBREVIATIONS

1.0 INTRODUCTION

1.1 Executive Summary

1.2 Historical Trend Graphs

2.0 SUPPLEMENTAL INFORMATION

2.1 Regulatory Limits

2.2 Effluent Concentration Limits

2.3 Measurements and Approximations of Total Radioactivity

2.4 Batch Releases

2.5 Abnormal (Unplanned) Releases

3.0 GASEOUS EFFLUENTS

4.0 LIQUID EFFLUENTS

5.0 SOLID WASTES

6.0 RADIOLOGICAL IMPACT ON MAN

6.1 Dose Due to Liquid Effluents

6.2 Dose Due to Gaseous Effluents

6.3 Dose Due to Radioiodines, Tritium, and Particulates

6.4 40CFR190 Dose Evaluation

6.5 Dose to a Member of the Public from Activities inside the Site Boundary

7.0 METEROLOGICAL DATA

7.1 Meteorological Monitoring Program

8.0 RELATED INFORMATION

8.1 Operability of Liquid and Gaseous Monitoring Instrumentation

8.2 Changes to the Offsite Dose Calculation Manual

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TABLE OF CONTENTS

8.3 New Locations for Dose Calculations or Environmental Monitoring

8.4 Liquid Holdup and Gas Storage Tanks

8.5 Noncompliance with Radiological Effluent Control Requirements

8.6 Resin Releases to the Low Volume Waste (LVW) Pond

8.7 Changes to the Liquid, Gaseous, and Solid Waste Treatment Systems

8.8 Groundwater Tritium Monitoring Program

8.9 Independent Spent Fuel Storage Installation (ISFSI)

9.0 EFFLUENT TABLES

9.1 Liquid and Gaseous Batch Release Summary

9.2 Abnormal Liquid and Gaseous Batch Release Summary

9.3 Gaseous Effluents - Summation of All Releases

9.4 Gaseous Effluents - Ground Level Releases

9.5 Liquid Effluents - Summation of All Releases

9.6 Liquid Effluents

9.7 Dose Due to Liquid Releases

9.8 Air Dose Due to Gaseous Releases

9.9 Dose Due to Radioiodines, Particulates, Tritium, and Carbon-14 in Gaseous Releases

9.10 Solid Radwaste and Irradiated Fuel Shipments

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10.0 ATTACHMENTS

10.1 Meteorological Joint Frequency Distribution Tables

10.2 Atmospheric Dispersion (X/Q) and Deposition (D/Q) Calculation Methodology Discussion

10.3 Carbon-14 Supplemental Information

10.4 Putting Radiation Dose in Context

10.5 Errata from Previous Annual Radioactive Effluent Release Reports

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ACRONYMS AND ABBREVIATIONS

AREOR Annual Radiological Environmental Operating Report CFR Code of Federal Regulations CPNPP Comanche Peak Nuclear Power Plant ECL Effluent Concentration Limit HIC High Integrity Containers ISFSI Independent Spent Fuel Storage Installation LDCR Licensing Document Change Request LHMT Laundry Holdup and Monitor Tanks LVW Low Volume Waste ODCM Offsite Dose Calculation Manual OOS Out of Service PET Primary Effluent Tanks pCi Pico-Curie REC Radiological Effluent Control SORC Station Operations Review Committee Ci Micro-Curie WMT Waste Monitor Tanks WWHT Waste Water Holdup Tanks

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1.0 Introduction

This Radioactive Effluent Release Report, for Comanche Peak Nuclear Power Plant (CPNPP) Unit 1 and Unit 2, is submitted as required by Technical Specification 5.6.3 and Offsite Dose Calculation Manual (ODCM) Administrative Control 6.9.1.4 for the period January 1, 2023 through December 31, 2023. Data in this report were calculated in accordance with the CPNPP ODCM using the OpenEMS software.

1.1 Executive Summary

The radioactive effluent monitoring program for 2023 was conducted as described in the following report. Results of the monitoring program indicate continued effort to maintain the release of radioactive effluents to the environment as low as reasonably achievable (ALARA).

In June 2009, the NRC provided revised guidance in Regulatory Guide 1.21, Measuring, Evaluating and Reporting Radioactive Material in Liquid and Gaseous Effluents and Solid Waste, Revision 2, establishing an updated approach for identifying principal radionuclides. Because the overall quantity of radioactive releases has steadily decreased due to improvements in power plant operations, Carbon-14 (C-14) now qualifies as a principal radionuclide (anything greater than one percent of overall radioactivity in effluents) under federal regulations at many plants. In other words, C-14 has not increased and C-14 is not a new nuclear plant emission. Rather, improvements in the mitigation of other isotopes have made C-14 more prominent. Attachment 10.3 provides more detail about C-14.

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1.1 Executive Summary (continued)

Gaseous Effluents:

Two-year summary of all the radioactive gaseous releases to the environment:

Gaseous Waste 2022 2023 Comments Tritium (Ci) 31.5 45.6 1 C-14 (Ci) 25.3 25.0 2 Total Fission and Activation Products (Ci) 0.41 0.51 Total Particulate (Ci) 0 0 3 Gross Alpha (Ci) 0 0 3 Iodine (Ci) 0 0 3 Calculated Gamma Air Dose (mRad) 3.62E-04 4.25E-04 4 Calculated Beta Air Dos e (mRad) 1.32E-04 1.59E-04 4 Total Body Dose (mRem) 0.08 0.103 5

Comments:

1. The major contributor to gaseous tritium activity is evaporation from the spent fuel pools.

Factors contributing to the tritium activity in the pools are related to the type of fuel used (i.e., 18-month fuel) the core life, power output, and number of core cycles. Two refueling outages occurred in 2023 which increased gaseous tritium released. Additionally, extreme Summer temperatures increased the evaporation rate of the spent fuel pools which also contributed to the tritium increase over the previo us year.

2. C-14 activity released from the site is estimated using reactor power in acco rdance with EPRI document "Estimation of Carbon-14 in Nuclear Power Plant Gaseous Effl uents".

3. No detectable particulate, gross alpha, or iodine activity was released during 2022 and 2023.

4. Calculated air dose will change from year to year based on the nuclides and their quantities being released. Each nuclide has a different dose factor. Therefore, annual air dose varies based on the nuclide mix and activity.

5. Total body dose increase due to higher noble gas and tritium activity released during the calendar year 2023. Two refueling outages took place during the year.

Overall the gaseous radioactivity releases from CPNPP are well controlled and maintained ALARA. CPNPP is well below all applicable limits for gaseous releases. Neither unit had any fuel defects during the year of this report.

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1.1 Executive Summary (continued)

Liquid Effluents:

Two-year summary of all the radioactive liquid releases to the environment:

Liquid Waste 2022 2023 Comments Total Activity Excluding Tritium (Ci) 3.73E-04 7.70E-04 2 Tritium Activity (Ci) 1,550 1,840 1, 3 Total Body Dose (mRem) 0.14 0.13 2 Total Volume Released (Gallons) 642,008 787,233

Comments:

1. Tritium released values may vary significantly from year to year due to fuel burnup characteristics which affects reactor coolant tritium production. Tritium activity increases following reactor startup, then plateaus mid-cycle, and begins to decline towards the end of cycle due to required dilutions. Its activity is also dependent upon how many unit outages there were during a calendar year. More liquid waste is processed and released during outages.

2. Total body dose is dependent upon the nuclide mix within the liquid releases. Some nuclides contribute to lower doses even though their activities may be higher.

3. Tritium released was higher due to two refueling outages during 2023.

Meteorological Data

During 2023, the CPNPP meteorological system achieved a 97.3% mean recoverable data rate for the joint frequency parameters required by Regulatory Guide 1.23 for wind speed, wind direction and delta temperature. See Section 7.1 for the actual recovery percentages.

Monitors OOS >30 Days

During 2023, there was one Technical Specification/ODCM effluent radiation monitor out of service (OOS) for greater than 30 days. The Auxiliary Building to LVW Pond Radiation Monitor, XRE-5251A was OOS for more than 30 days due to troubleshooting, acquiring replacement parts, and the availability of qualified personnel. The monitor was declared OOS in late December 2023 and exceeded the 30 day OOS period in late January 2024. The monitor was returned to service on 2/21/2024. (CR-2024-000493).

ODCM Changes

There were no revisions to the ODCM during 2023.

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1.1 Executive Summary (continued)

Solid Waste

Two-year summary of th e solid waste production:

Total Waste 2022 2023 % Error Shipped (m3) 486 271 +/-25%

Shipped (Ci) 1410 318 +/-25%

Buried (m3) 325 247 +/-25%

Buried (Ci) 1410 325 +/-25%

Comments:

Volume: In 2023, the shipped waste volume decrease over the previous year was due to an extensive shipping campaign to reduce onsite waste inventory in 2022 and a large amount of our backlogged waste was shipped offsite. Additionally, 2023 was a two refueling outage year so having available resources limited the extensive shipping campaign.

Activity: In 2023, the activity shipped was lower for the same reason as the volume decrease above.

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Groundwater Tritium

Water wells used to monitor CPNPP for tritium leaks into groundwater all had results that were less than the minimum detectable activity (MDA), with the exception of Monitoring Well 11 (MW-11) during 2023 as indicated in Table 1. MW-11 rendered positive results for the last three quarters of 2022. Tracking Report TR-2022-004991 was initiated due to the second quarter result of 2180 pCi/L on Monitoring Well No. 11. One follow-up sample was analyzed to verify the elevated result. No concl usive determination could be made based on investigation. Sample was in an area that was affected by a leak the prior year and an active leak of lake water (containing elevated tritium levels). The third and fourth quarter results were attributed to the same unknown plume. All of these sample results were much less than the drinking water limit of 20,000 pCi/L.

See Section 8.8 for details.

Conclusion

During 2023, the radiological effluent monitoring program was conducted in an appropriate manner to ensure the activity released and associated dose to the public has been maintained as low as reasonably achievable (ALARA).

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1.2 Historical Trend Graphs

Year Total Gaseous Fission and Activation Activity Released Comments All Total activity released in gaseouseffluents can vary year to year depending on the number of refueling and maintenance outages, as well as other factors.

2020 2020 radioactive noble gaseous activity released was higher than 2019 due to more Argon-41 (Ar-41) gas activity released. Ar-41 is the major constituent of the total radioactive gas released from the site. Non-radioactive argon gas is routinely added to the Reactor Coolant System (RCS) and then activated to radioactive Ar-41 to enhance detection of primary to secondary leakage. Leaks in each units argon injection system were found and repaired late 2019. The repairs resulted in higher Ar-41 activity released in 2020 compared to the 2019 activity released (CR-2019-007553).

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Year Total Gaseous Tritium Released Comments All A major contributor to gaseous tritium activity is evaporation from the spent fuel pools.

Variables contributing to the tritium activity in the pools are based on the type of fuel used (i.e., 18-month fuel), the core life, power output, and number of core cycles.

2023 Increase due to two refueling outages and increased evaporation from the spent fuel pool.

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Year Total Body Dose due to Gaseous Activity Released Comments 2023 Increase due to higher noble gas and tritium activity released during 2023.

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Year Total Volume Liquid Effluents Released Comments All Total volume of liquid effluents released can vary significantly from year to year depending on the number of refueling and maintenance outages. More liquid waste is processed and released during these outages.

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Year Total Activity (Excluding Tritium) Released in Liquid Effluents Comments All Total activity released in liquid effluents can v ary year to year depending on the number of refueling and maintenance outages, as well as other factors.

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Year Total Curies of Tritium Released in Liquid Effluents Comments All Tritium released values can vary significantly from year to year based on a couple of reasons. First, reactor coolant tritium production changes based on fuel burnup characteristics. Tritium activity increases following reactor startup, then plateaus mid-cycle, and begins to decline towards the end of cycle. Second, the tritium released value is dependent upon on how many outages there were during a calendar year. More liquid waste is processed and released during unit outages.

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Year Total Body Dose Due to Liquid Effluents Released Comments N/A No comments.

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Total Volume of Solid Radwaste Buried Comments Year 2017 2017 was a multi-outage year which led to a higher volume of solid waste shipped and buried.

2018 Shipments of waste during 2018 were based on a one outage year since the last Unit 2 outage carried over into 2019. Additionally, the efficiency methods in place have reduced the shipped/buried volume of waste during the last few years.

2019 The waste volume increase over the previous year was due to an effort to reduce onsite waste inventory. The spent resin inventory was near capacity and a resin shipping campaign was undertaken shipping 5 HICs offsite to make space to support interim resin storage for planned plant operational needs. Additionally, we had several Energy Solutions Sea Land containers stored onsite containing Dry Active Waste (DAW). To avoid continuing to pay rental costs on these containers and to reduce waste inventory, 10 Sea Lands were returned to Energy Solutions in a DAW shipping campaign.

2020 In 2020, the decrease in shipped and buriedwaste volume was due to making only two DAW shipments compared to five in 2019. Additionally, only three High Integrity Containers of spent resins were shipped in 2020 as compared to five in 2019.

2021 and The increase in waste volume buried during these years is due to an effort to reduce our backlog of 2022 radwaste stored on site. A significant radwaste backlog has accumulated over the past few years and the station has implemented a multi-year plan to reduce and ultimately eliminate this backlog.

2023 Solid radwaste backlog volume reduction continued through 2023.

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Year Total Curies of Solid Radwaste Buried Comments 2017 Lower total activity buried was due to solid waste having lower activity.

2018 During 2018, CPNPP shipped off 5 High Integrity Containers (HICs) containing high activity resin in order to make room for future resin transfers and filter changes. These shipments were necessary to ensure the expected volume of resin transferred from the plant during 2019 could be properly stored on site. These shipments led to higher values for Curies shipped and buried for 2018.

2019 The majority of waste shipped offsite was Dry Active Waste (DAW) with low activity. While the total volume buried increased significantly over the previous years (refer to Total Volume of Solid Radwaste Buried histogram on next page), the Curies buried was much lower.

2020 The shipped and buried total activity was more than double the activity shipped in 2019. One of the High Integrity Containers shipped in 2020 was a Waste Class C shipment which by itself had an activity level 30% greater than the total sum of all activity shipped in 2019.

2021 No comments 2022 The spent resin inventory was near the capacity of the shielded vaults and a resin shipping campaign was undertaken. 15 High Integrity Containers were shipped offsite to make space to support resin and filter storage capacity for planned plant operational needs. Seven of the 15 High Integrity Containers shipped were waste Class B and C which have much higher activity than waste Class A containers.

This significantly added to the total shipped activity from previous years.

2023 No comments

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2.0 SUPPLEMENTAL INFORMATION

2.1 Regulatory Limits

The ODCM Radiological Effluent Control limits applicable to the release of radioactive material in liquid and gaseous effluents are described in the following sections.

2.1.1 Fission and Activation Gases (Noble Gases)

The dose rate due to radioactive materi als released in gaseous effluents from the site to areas at and beyond the site boundary shall be limited to less than or equal to 500 mRem/yr to the whole body and less than or equal to 3000 mRem/yr to the skin.

The air dose due to noble gases released in gaseous effluents, from each unit, to areas at and beyond the site boundary shall be limited to the following:

a. During any calendar quarter: Less than or equal to 5 mRad for gamma radiation and less than or equal to 10 mRad for beta radiation, and

b. During any calendar year: Less than or equal to 10 mRad for gamma radiation and less than or equal to 20 mRad for beta radiation.

2.1.2 Iodine-131, Iodine-133, Tritium and Radioactive Material in Particulate Form

The dose rate due to iodine-131, iodine-133, tritium, and all radionuclides in particulate form with half-lives greater than 8 days, released in gaseous effluents from the site to areas at and beyond the site boundary, shall be limited to less than or equal to 1500 mRem/yr to any organ.

The dose to a MEMBER OF THE PUBLIC from iodine-131, iodine-133, tritium and all radionuclides in particulate form with half-lives greater than 8 days, in gaseous effluents released, from each unit, to areas at and beyond the site boundary, shall be limited to the following:

a. During any calendar quarter: Less than or equal to 7.5 mRem to any organ, and

b. During any calendar year: Less than or equal to 15 mRem to any organ.

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2.1.3 Liquid Effluents

The concentration of radioactive material released in liquid effluents to unrestricted areas shall be limited to 10 times the concentrations specified in 10 CFR Part 20, Appendix B, Table 2, Column 2 for radionuclides other than dissolved or entrained noble gases. For dissolved or entrained noble gases, the concentration shall be limited to 2.0E-L total activity.

The dose or dose commitment to a MEMBER OF THE PUBLIC from radioactive materials in liquid effluents released, from each unit, to unrestricted areas shall be limited:

a. During any calendar quarter to less than or equal to 1.5 mRem to the whole body and to less than or equal to 5 mRem to any organ, and

b. During any calendar year to less than or equal to 3 mRem to the whole body and to less than or equal to 10 mRem to any organ.

2.1.4 LVW Pond Resin Inventory

The quantity of radioactive material contained in resins transferred to the LVW pond shall be limited by the following expression:

(264/V) j Aj/Cj < 1.0

excluding tritium, dissolved or entrained noble gases and radionuclides with less than an 8-day half-life, where:

Aj = pond inventory limit for a single radionuclide j (Curies),

Cj = 10CFR20, Appendix B, Table 2 Column 2, concentration for a single L),

V = volume of resins in the pond (gallons), and

264 = conversion factor (Ci/Ci per mL/gal)

This expression limits the total quantity of radioactive materials in resins discharged to the LVW Pond to a value such that the average concentration in the resins, calculated over the total volume of resins in the pond, will not exceed one times the Effluent Concentration Limits specified in 10 CFR 20, Appendix B, Table 2, Column 2.

2.1.5 Total Dose

The annual (calendar year) dose or dose commitment to any MEMBER OF THE PUBLIC due to releases of radioactivity and to radiation from uranium fuel cycle sources shall be limited to less than or equal to 25 mRem to the whole body or any organ, except the thyroid, which shall be limited to less than or equal to 75 mRem.

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2.2 Effluent Concentration Limits

2.2.1 Gaseous Effluents

For gaseous effluents, effluent concentration limits (ECL) values are not directly used in release rate calculations since the applicable limits are expressed in terms of dose rate at the site boundary.

2.2.2 Liquid Effluents

The values specified in 10 CFR Part 20, Appendix B, Table 2, Column 2 are used as the ECL for liquid radioactive effluents released to unrestricted areas. A value of 2.0E-L is used as the ECL for dissolved and entrained noble gases in liquid effluents.

2.3 Measurements and Approximations of Total Radioactivity

Measurements of total radioactivity in liquid and gaseous radioactive effluents were accomplished in accordance with the sampling and analysis requirements of Tables 4.11-1 and 4.11-2, respectively, of the CPNPP ODCM.

2.3.1 Liquid Radioactive Effluents

Each batch release was sampled and analyzed for gamma emitting radionuclides using gamma spectroscopy. Composite samples were analyzed monthly and quarterly for the Primary Effluent Tanks (PET), Waste Monitor Tanks (WMT), Laundry Holdup and Monitor Tanks (LHMT), and Waste Water Holdup Tanks (WWHT). Composite samples were analyzed monthly for tritium and gross alpha radioactivity in the onsite laboratory using liquid scintillation and gas flow proportional counting techniques, respectively. Composite samples were analyzed quarterly for Sr-89, Sr-90, Fe-55, and Ni-63 by a contract laboratory. The results of the composite analyses from the previous month or quarter were used to estimate the quantities of these radionuclides in liquid effluents during the current month or quarter. The total radioactivity in liquid effluent releases was determined from the measured and estimated concentrations of each radionuclide present and the total volume of the effluent released during periods of discharge.

For batch releases of powdex resin to the LVW pond, samples were analyzed for gamma emitting radionuclides, using gamma spectroscopy techniques. Composite samples were analyzed quarterly for Sr-89 and Sr-90 by a contract laboratory.

For continuous releases to the Circulating Water Discharge from the LVW pond, daily grab samples were obtained over the period of pond discharge. These samples were composited and analyzed for gamma emitting radionuclides, using gamma spectroscopy techniques. Composite samples were also analyzed for tritium and gross alpha radioactivity using liquid scintillation and gas flow proportional counting techniques, respectively. Composite samples were analyzed quarterly for Sr-89, Sr-90, Fe-55, and Ni-63 by a contract laboratory.

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2.3.2 Gaseous Radioactive Effluents

Each gaseous batch release was sampled and analyzed for radioactivity prior to release. Waste Gas Decay Tank samples were analyzed for gamma emitting radionuclides. Containment Building charcoal (iodine), particulate, noble gas, and tritium grab samples were also analyzed for radioactivity prior to each release. The results of the analyses and the total volume of effluent released were used to determine the total amount of radioactivity released in the batch mode.

For continuous effluent release pathways, noble gas and tritium grab samples were collected and analyzed weekly. Samples were analyzed for gamma emitting radionuclides by gamma spectroscopy and liquid scintillation counting techniques. Continuous release pathways were continuously sampled using radioiodine adsorbers and particulate filters. The radioiodine adsorbers and particulate filters were analyzed weekly for I-131 and gamma emitting radionuclides using gamma spectroscopy. Results of the noble gas and tritium grab samples, radioiodine adsorber and particulate filter analyses from the current week, and the average effluent flow rate for the previous week were used to determine the total amount of radioactivity released in the continuous mode. Monthly composites of particulate filters were analyzed for gross alpha activity, in the onsite laboratory using the gas flow proportional counting technique. Quarterly composites of particulate filters were analyzed for Sr-89 and Sr-90 by a contract laboratory.

C-14 was estimated in accordance with the methodology in the EPRI report Estimation of Carbon-14 in Nuclear Power Plant Gaseous Effluents. EPRI, Palo Alto, CA: 2010, 1021106. See Attachment 10.3 for more information on C-14.

2.4 Batch Releases

A summary of information for liquid and gaseous batch releases is included in Table 9.1.

2.5 Abnormal (Unplanned) Releases

Abnormal releases are defined as unplanned or uncontrolled releases of radioactive material from the site boundary. There were no abnormal (unplanned) liquid or gaseous radioactive effluent releases during 2023.

3.0 GASEOUS EFFLUENTS

The quantities of radioactive material released in gaseous effluents are summarized in Tables 9.3 and 9.4. All releases of radioactive material in gaseous form are considered to be ground level releases.

4.0 LIQUID EFFLUENTS

The quantities of radioactive material released in liquid effluents are summarized in Tables 9.5 and 9.6.

5.0 SOLID WASTES

The quantities of radioactive material released as solid wastes are summarized in Table 9.10.

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6.0 RADIOLOGICAL IMPACT ON MAN

6.1 Dose Due to Liquid Effluents

Dose to an adult from the fish and cow-m eat consumption pathways from Squaw Creek Reservoir was calculated in accordance with the methodology and parameters in the ODCM. Results of the calculations are summarized on a quarterly and annual basis in Table 9.7.

6.2 Dose Due to Gaseous Effluents

Air doses due to gaseous effluent gamma and beta emissions were calculated using the highest annual average atmospheric dispersion factor at the Site Boundary location, in accordance with the methodology and parameters in the ODCM. Results of the calculations are summarized on a quarterly and annual basis in Table 9.8.

6.3 Dose Due to Radioiodines, Tritium, and Particulates in Gaseous Releases

Dose to an adult, teen, child, and infant from radioiodines and particulates, for the pathways listed in Part II, Table 2.4 of the ODCM, were calculated using the highest dispersion and deposition factors, as appropriate, in accordance with the methodology and parameters in the ODCM. The results of the calculations are summarized on a quarterly and annual basis in Table 9.9. Because of pathway similarity, C-14 dose is included in this table.

6.4 40CFR190 Dose Evaluation

ODCM Radiological Effluent Control 3.11.4 requires dose evaluations to demonstrate compliance with 40 CFR Part 190 only if the calculated quarterly or yearly dose exceed two times the applicable quarterly or annual dose limits. At no time during 2023 were any of these limits exceeded; therefore, no evaluations are required.

6.5 Dose to a Member of the Public from Activities Inside the Site Boundary

Dose to a Member of the Public from activities inside the site boundary was evaluated. The highest dose resulted from recreational fishing on Squaw Creek Reservoir. A dose of 3.48E-03 mRem/yr was calculated based on an individual fishing twice a week, five hours each day, six months per year. Pathways included in the calculation were gaseous inhalation and submersion.

Liquid pathways are not considered since all doses are calculated at the point of circulation water discharge into the reservoir.

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7.0 METEROLOGICAL DATA

7.1 Meteorological Monitoring Program

In accordance with ODCM Administrative Control 6.9.1.4, a summary of hourly meteorological data, collected during 2023 is retained onsite. These data are available for review by the NRC upon request. Joint Frequency Tables are included in Attachment 10.1. During the year of this report, the goal of > 90% joint data recovery was met. The individual percent recoveries are listed below:

Meteorological Data Recovery Channel % Recovery 10 m Wind Speed 98.7 10 m Wind Direction 99.9 Delta Temperature A 92.0 Delta Temperature B 98.4

8.0 RELATED INFORMATION

8.1 Operability of Liquid and Gaseous Monitoring Instrumentation

ODCM Radiological Effluent Controls 3.3.3.4 and 3.3.3.5 require an explanation of why designated inoperable liquid and gaseous monitoring instrumentation was not restored to operable status within 30 days.

During 2023, there was one Technical Specification/ODCM effluent radiation monitor out of service (OOS) for greater than 30 days. The Auxiliary Building to LVW Pond Radiation Monitor, XRE-5251A was OOS for more than 30 days due to troubleshooting, acquiring replacement parts, and the availability of qualified personnel. The monitor was declared OOS in late December 2023 and exceeded the 30 day OOS period in late January 2024. The monitor was returned to service on 2/21/2024. (CR-2024-000493).

8.2 Changes to the Offsite Dose Calculation Manual

No changes were made to the ODCM during 2023.

8.3 New Locations for Dose Calculations or Environmental Monitoring

ODCM Administrative Control 6.9.1.4 requires any new locations for dose calculations and/or environmental monitoring, identified by the Land Use Census, to be included in the Radioactive Effluent Release Report. Based on the 2023 Land Use Census, no new receptor locations were identified which resulted in changes requiring a revision in current environmental sample locations. Values for the current nearest resident, milk animal, garden, X/Q and D/Q values in all sectors surrounding CPNPP were included in the 2023 Land Use Census.

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8.4 Liquid Holdup and Gas Storage Tanks

ODCM Administrative Control 6.9.1.4 requires a description of the events leading to liquid holdup or gas storage tanks exceeding the limits required to be established by Technical Specification 5.5.12. Technical Requirements Manual 13.10.33 limits the quantity of radioactive material contained in each unprotected outdoor tank to less than or equal to 10 Curies, excluding tritium and dissolved or entrained noble gases. Technical Requirements Manual 13.10.32 limits the quantity of radioactive material contained in each gas storage tank to less than or equal to 200,000 Curies of noble gases (considered as Xe-133 equivalent). These limits were not exceeded during the period covered by this report.

8.5 Noncompliance with Radiological Effluent Control Requirements

This section provides a listing and description of Abnormal Releases, issues that did not comply with the applicable requirements of the Radiological Effluents Controls given in Part I of the CPNPP ODCM and/or issues that did not comply with associated Administrative Controls and that failed to meet CPNPP expectations regarding Station Radioactive Effluent Controls. Detailed documentation concerning evaluations of these events and corrective actions is maintained onsite.

8.5.1 Abnormal (Unplanned) Gaseous Effluent Release

No abnormal (unplanned) gaseous effluent releases occurred during 2023.

8.5.2 Abnormal (Unplanned) Liquid Effluent Releases

No abnormal (unplanned) liquid effluent releases occurred during 2023.

Page 26 of 57 TXX-24023 Enclosure Page 27 of 57

8.6 Resin Releases to the Low Volume Waste (LVW) Pond

A total of 128 ft3 of powdex resin was transferred to the LVW pond during 2023. The cumulative activity deposited in the LVW pond since operations began through the end of 2023 is 1.76E-03 Curies, consisting of Co-58, Co-60, Cs-134, Cs-137, I-131, Sr-90 and Sb-125.

8.7 Changes to the Liquid, Gaseous, and Solid Waste Treatment Systems

In accordance with the C PNPP Process Control Program, Section 6.2.6.2, changes to the Radwaste Treatment Systems (liquid, gaseous, and solid) should be summarized and reported to the Commission in the Radioactive Effluent Release Report if the changes implemented required a 10CFR50.59 safety evaluation.

During 2023, no changes to the Radwaste Treatment Systems occurred meeting the reporting criteria of the Process Control Program.

8.8 Groundwater Tritium Monitoring Program

The monitoring well network at CPNPP includes 12 wells completed in the un-weathered and weathered portions of the Glen Rose Formation. Two monitoring wells are located near the Refueling Water Storage Tank (one at each RWST). Three wells are near or down-gradient of the fuel building (East Side). Four other wells are situated on the periphery North, South and West of the Power Block. Three monitoring wells were placed along the wastewater management system underground piping. Each of the wells are sampled on a quarterly frequency to test for contamination via gamma spectroscopy and Liquid Scintillation.

Water wells used to monitor CPNPP for tritium leaks into groundwater all had results that were less than the minimum detectable activity (MDA), except for Monitoring Well 11 (MW-11) during 2023 as indicated in Table 1. MW-11 rendered positive results for the first three quarters of 2023. From the 1st quarter of 2022 to the 3rd quarter of 2023 MW-11 has consistently rendered positive results that ranged from 2,180 to 3,080 pCi/L. MW-11 is in an area that was affected by a leak in 2021 (documented in TR-2021-007547), and a persistent leak of lake water (containing elevated tritium levels), through the end of 2022. Tracking Report TR-2022-004991 was initiated in 2022 due to the initial positive result. An investigation could not conclusively distinguish whether the likelihood of positive samples was from the historical leak, a leak of lake water or from another source. All these sample results were much less than the drinking water limit of 20,000 pCi/L.

A Hydrogeology study performed by Golder Associates, Inc., described that CPNPP has perched water above an impermeable layer of bedrock. The 160- to 270-foot-thick Glen Rose Formation (the top layer) is not considered a source of useful groundwater in the vicinity of CPNPP as it carries very little water and is unreliable in times of drought. The thickness and mostly impermeable nature of the Glen Rose Formation prevents migration of potentially contaminated groundwater to the underlying Twin Mountains Formation.

Continued monitoring of perched water sample points will occur as part of the Groundwater Monitoring Program (STA-654). Any new sources of tritium or increase in the activity will be evaluated and remediated as necessary.

Page 27 of 57 TXX-24023 Enclosure Page 28 of 57

Table 1 2023 Perched Groundwater Tritium Samples in PicoCuries Per Liter

MW 3/23/2023 6/28/2023 9/25/2023 12/12/2023*

Location 9 <1090 <1030 <1040 <1000 - 2070 10 <1090 <1030 <1040 <1000 - 2070 11 <2130 2180 2400 <1000 - 2070 12 <1090 <1030 <1040 <1000 - 2070 14 <1090 <1030 <1040 <1000 - 2070 15 <1090 <1030 <1040 <1000 - 2070 16 <1090 <1030 <1040 <1000 - 2070 19 <1090 <1030 <1040 <1000 - 2070 25 <1090 <1030 <1040 <1000 - 2070 CP-A <1090 <1030 <1040 <1000 - 2070 CP-B <1090 <1030 <1040 <1000 - 2070 CP-C <1090 <1030 <1040 <1000 - 2070

• Results for 12/12/23 encountered a change in background results which required a restart of counting some samples. Due to this background fluctuation some Minimum Detectable Activities were 1,000 pCi/L while others were 2,070 pCi/L. the required Minimum Detectable Activity for non-drinking water samples is 3,000 pCi/L.

Page 28 of 57

TXX-24023 Enclosure Page 30 of 57

8.9 Independent Spent Fuel Storage Installation (ISFSI)

There are no radiological effluents released from the ISFSI. Direct dose from this installation is monitored using the normal environmental direct dose program and reported in the Annual Radiological Environmental Operating Report (AREOR).

Page 30 of 57 TXX-24023 Enclosure Page 31 of 57

SECTION 9.0 EFFLUENT TABLE S

Page 31 of 57

TXX-24023 Enclosure Page 34 of 57 Table 9.3 Gaseous Effluents - Summation of All Releases

Type of Effluent Units Quarter Quarter Quarter Quarter 1 2 3 4 Total A. Fission and Activation Gases

1. Total Release Curies 1.08E-01 1.40E-01 1.09E-01 1.54E-01 4.06E-01

2. Average Release rate for period 1.39E-02 1.78E-02 1.38E-02 1.94E-02 1.62E-02

3. Percent of Applicable Limit % * * * *

• B. Radioiodines

1. Total Iodine-131 Curies 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

2. Average Release rate for period 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

3. Percent of Applicable Limit % * * * *

• C. Particulates

1. Particulates (Half-Lives > 8 Curies 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 Days)

2. Average Release rate for period 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

3. Percent of Applicable Limit % * * * *

• D. Tritium

1. H-3 Release Curies 6.34E+00 1.22E+01 1.78E+01 9.34E+00 4.56E+01

2. Average Release rate for period 8.15E-01 1.55E+00 2.23E+00 1.18E+00 1.45E+00

3. Percent of Applicable Limit % * * * *

• E. Carbon-14

1. C-14 Release Curies 6.82E+00 5.36E+00 6.97E+00 5.83E+00 2.50E+01

2. Average Release rate for period 8.77E-01 6.81E-01 8.73E-01 7.37E-01 7.92E-01

3. Percent of Applicable Limit % * * * *

• F. Gross Alpha

1. Total Release Curies 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

• Applicable limits are expressed in terms of dose.

Estimated Total Error for All Values Reported Is < 1.0%

Page 34 of 57 TXX-24023 Enclosure Page 35 of 57 Table 9.4 Gaseous Effluents - Ground Level Releases

Continuous Mode Nuclides Released Units Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total

Fission Gases No Nuclides Found Curies 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

Iodines No Nuclides Found Curies 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

Particulates No Nuclides Found Curies 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

Tritium H-3 Curies 6.28E+00 1.21E+01 1.77E+01 9.30E+00 4.54E+01

Carbon-14 C-14 Curies 4.77E+00 3.75E+00 4.88E+00 4.08E+00 1.75E+01

Gross Alpha No Nuclides Found Curies 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

If Not Detected, Nuclide is Not reported.

Zeros in this table indicate that no radioactivity was present at detectable levels.

Page 35 of 57 TXX-24023 Enclosure Page 36 of 57 Table 9.4 (continued)

Gaseous Effluents - Ground Level Releases

Batch Mode Nuclides Released Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total

Fission Gases Ar-41 Curies 9.59E-02 1.12E-01 9.70E-02 1.27E-01 4.32E-01 Kr-85m Curies 0.00E+00 4.74E-05 0.00E+00 4.97E-05 9.71E-05 Kr-85 Curies 0.00E+00 6.90E-05 0.00E+00 0.00E+00 6.90E-05 Xe-131m Curies 0.00E+00 1.17E-05 0.00E+00 0.00E+00 1.17E-05 Xe-133m Curies 0.00E+00 1.02E-04 0.00E+00 1.59E-04 2.61E-04 Xe-133 Curies 1.25E-02 2.21E-02 1.25E-02 2.10E-02 6.80E-02 Xe-135m Curies 0.00E+00 6.79E-04 0.00E+00 1.42E-05 6.93E-04 Xe-135 Curies 0.00E+00 4.60E-03 0.00E+00 6.09E-03 1.07E-02 Total for Period Curies 1.08E-01 1.40E-01 1.09E-01 1.54E-01 5.12E-01

Iodines No Nuclides Found Curies 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

Particulates No Nuclides Found Curies 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

Tritium H-3 Curies 5.55E-02 7.24E-02 4.08E-02 3.76E-02 2.06E-01

Carbon-14 C-14 Curies2.05E+001.61E+002.09E+00 1.75E+00 7.50E+00

Gross Alpha No Nuclides Found Curies 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

If Not Detected, Nuclide is Not reported.

Zeros in this table indicate that no radioactivity was present at detectable levels.

Page 36 of 57

TXX-24023 Enclosure Page 38 of 57 Table 9.6 Liquid Effluents

Continuous Mode Nuclides Released Units Quarter 1 Quarter 2 Quarter 3 Quarter 4 Annual Fission and Activation Products No Nuclides Found Curies 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

Tritium H-3 Curies 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

Dissolved and Entrained Gases No Nuclides Found Curies 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

Gross Alpha Radioactivity Curies 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

Batch Mode Nuclides Released Units Quarter 1 Quarter 2 Quarter 3 Quarter 4 Annual

A. Fission and Activation Products

Cr-51 Curies 0.00E+00 4.06E-05 5.22E-05 6.58E-05 1.59E-04 Co-58 Curies 0.00E+00 6.54E-05 1.25E-04 2.13E-04 4.04E-04 Co-60 Curies 2.37E-05 3.33E-05 4.86E-05 6.79E-05 1.73E-04 As-76 Curies 0.00E+00 1.56E-05 0.00E+00 0.00E+00 1.56E-05 Nb-95 Curies0.00E+003.37E-06 6.34E-06 9.34E-06 1.90E-05 Total for Period Curies2.37E-05 1.58E-04 2.32E-04 3.56E-04 7.70E-04

B. Tritium H-3 Curies 5.87E+02 6.77E+02 2.91E+02 2.89E+02 1.84E+03

C. Dissolved and Entrained Gases Xe-133 Curies 1.57E-04 3.04E-04 6.39E-05 2.14E-04 7.38E-04 Xe-135 Curies 0.00E+00 1.48E-06 0.00E+00 0.00E+00 1.48E-06 Total for Period Curies1.57E-04 3.05E-04 6.39E-05 2.14E-04 7.40E-04

D. Gross Alpha Activity No Nuclides Found Curies 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

If Not Detected, Nuclide is Not reported.

Zeros in this table indicate that no radioactivity was present at detectable levels.

Page 38 of 57 TXX-24023 Enclosure Page 39 of 57 Table 9.7 Dose Due to Liquid Releases

Organ Dose Units Quarter 1 Quarter 2 Quarter 3 Quarter 4 Annual

Bone mRem 0.00E+00 6.68E-09 1.26E-08 1.85E-08 3.78E-08 Limit mRem 5 5 5 5 10 Percent of Limit %0 0 0 0 0

Liver mRem 2.87E-02 3.08E-02 3.50E-02 3.88E-02 1.33E-01 Limit mRem 5 5 5 5 10 Percent of Limit % 0.575 0.616 0.700 0.777 1.334

Total Body mRem 2.87E-02 3.08E-02 3.50E-02 3.88E-02 1.33E-01 Limit mRem 1.5 1.5 1.5 1.5 3 Percent of Limit % 1.917 2.054 2.332 2.589 4.446

Thyroid mRem 2.87E-02 3.08E-02 3.50E-02 3.88E-02 1.33E-01 Limit mRem 5 5 5 5 10 Percent of Limit % 0.575 0.616 0.700 0.777 1.334

Kidney mRem 2.87E-02 3.08E-02 3.50E-02 3.88E-02 1.33E-01 Limit mRem 5 5 5 5 10 Percent of Limit % 0.575 0.616 0.700 0.777 1.334

Lung mRem 2.87E-02 3.08E-02 3.50E-02 3.88E-02 1.33E-01 Limit mRem 5 5 5 5 10 Percent of Limit % 0.575 0.616 0.700 0.777 1.334

GI-Lli mRem 2.87E-02 3.08E-02 3.50E-02 3.88E-02 1.33E-01 Limit mRem 5 5 5 5 10 Percent of Limit % 0.575 0.616 0.700 0.777 1.334

Page 39 of 57 TXX-24023 Enclosure Page 40 of 57 Table 9.8 Air Dose Due To Gaseous Releases

NG Dose Units Quarter 1 Quarter 2 Quarter 3 Quarter 4 Annual Gamma Air mRad 1.15E-04 9.18E-05 7.50E-05 7.94E-05 3.62E-04 Limit mRad 5 5 5 5 10 Percent of Limit % 0.002 0.002 0.001 0.002 0.004

Beta Air mRad 4.11E-05 3.40E-05 2.74E-05 2.90E-05 1.32E-04 Limit mRad1010101020 Percent of Limit % 0 0 0 0 0.001

NG Total Body mRem 1.10E-04 8.72E-05 7.12E-05 7.54E-05 3.44E-04 Limit mRem 7.5 7.5 7.5 7.5 15 Percent of Limit % 0.001 0.001 0.001 0.001 0.002

NG Skin mRem 1.60E-04 1.28E-04 1.04E-04 1.11E-04 5.04E-04 Limit mRem 7.5 7.5 7.5 7.5 15 Percent of Limit % 0.002 0.002 0.001 0.001 0.003

Page 40 of 57 TXX-24023 Enclosure Page 41 of 57

Table 9.9 Dose Due to Radioiodines, Particulates, Tritium, and Carbon-14 in Gaseous Releases

Organ Dose Units Quarter 1 Quarter 2 Quarter 3 Quarter 4 Annual

Liver mRem 2.08E-02 2.10E-02 2.40E-02 1.78E-02 8.35E-02 Limit mRem 7.5 7.5 7.5 7.5 15 Percent of Limit % 0.277 0.280 0.319 0.237 0.557

Total Body mRem 2.08E-02 2.10E-02 2.40E-02 1.78E-02 8.35E-02 Limit mRem 7.5 7.5 7.5 7.5 145 Percent of Limit % 0.277 0.280 0.319 0.237 0.557

Thyroid mRem 2.08E-02 2.10E-02 2.40E-02 1.78E-02 8.35E-02 Limit mRem 7.5 7.5 7.5 7.5 15 Percent of Limit % 0.277 0.280 0.319 0.237 0.557

Kidney mRem 2.08E-02 2.10E-02 2.40E-02 1.78E-02 8.35E-02 Limit mRem 7.5 7.5 7.5 7.5 15 Percent of Limit % 0.277 0.280 0.319 0.237 0.557

Lung mRem 2.08E-02 2.10E-02 2.40E-02 1.78E-02 8.35E-02 Limit mRem 7.5 7.5 7.5 7.5 15 Percent of Limit % 0.277 0.280 0.319 0.237 0.557

GI-Lli mRem 2.08E-02 2.10E-02 2.40E-02 1.78E-02 8.35E-02 Limit mRem 7.5 7.5 7.5 7.5 15 Percent of Limit % 0.277 0.280 0.319 0.237 0.557

Bone mRem 5.43E-02 5.13E-02 5.58E-02 4.26E-02 2.04E-01 Limit mRem 7.5 7.5 7.5 7.5 15 Percent of Limit % 0.724 0.685 0.744 0.567 1.360

Page 41 of 57 TXX-24023 Enclosure Page 42 of 57

Table 9.10 Solid Radwaste and Irradiated Fuel Shipments

A. Solid Waste Shipped Offsite for Burial or Disposal (Not Irradiated Fuel)

1. Type of Waste ShippedBuried Percent m3 ShippedCim3 BuriedCiError

a. Spent resins/filters 1.02E+01 3.18E+02 1.02E+01 3.18E+02 +/- 25%

b. Dry active waste 2.61E+02 9.38E-02 2.37E+02 7.72E+00 +/- 25%

c. Irradiated components 0 0 0 0 N/A

d. Other (oil/miscellaneous liquids sent to 0 0 0 0 N/A processor for volume reduction)

TOTAL 2.71E+02 3.18E+02 2.47E+02 3.25E+02 +/- 25%

Note: Shipped volumes and curies are not always equal to the buried volumes and curies as a result of volume reducing processing, and some disposal occurs outside the twelve-month time period in which shipments occurred.

Dry active waste also includes some low-level radioactive resins, tank sediments, and filters that are handled and processed in a manner that is consistent with this waste stream.

2. Estimate of Major Nuclide Composition (by type of waste) Nuclide % Activity Abundance Ci

a. Spent resins/filters Ni-63 76.17 2.42E+02 Fe-55 13.29 4.22E+01 Co-60 8.68 2.75E+01 Ni-59 0.49 1.55E+00 Mn-54 0.38 1.21E+00 Sb-125 0.36 1.15E+00 Cs-137d 0.29 9.14E-01 C-14 0.22 6.84E-01 Co-57 0.06 1.81E-01 H-3 0.04 1.38E-01 Sr-90d 0.01 4.40E-02 Co-58 0.00 1.00E-02 Tc-99 0.00 4.25E-03 I-129 LLD Other (1) <0.01 <3.18E-02 Total 100.00 3.18E+02

b. Dry active waste Co-60 36.21 3.40E-02 Fe-55 30.97 2.90E-02 Ni-63 17.47 1.64E-02 Co-58 6.66 6.24E-03 Nb-95 2.23 2.09E-03 Cr-51 1.72 1.61E-03 Mn-54 1.53 1.44E-03 Zr-95 1.17 1.10E-03 Sb-125 1.15 1.08E-03 C-14 0.44 4.13E-04 Cs-137d 0.21 2.00E-04 Tc-99 0.08 7.49E-05 H-3 (LLD) I-129 (LLD) Other (2) <0.01 <9.38E-6 Total 100.00 9.38E-02

(1) Nuclides representing <1% of total shipped activity: Sb-125, Cs-137d, C-14, Co-57, H-3, Sr-90 and Tc-99.

(2) Nuclides representing <1% of total shipped activity: C-14, Cs-137d, Co-57 and Tc-99.

Page 42 of 57 TXX-24023 Enclosure Page 43 of 57

Table 9.10 (continued)

Solid Radwaste and Irradiated Fuel Shipments

3. Solid Waste Disposition (Mode of Transportation: Truck)

Waste Type WasteContainerNumber of Class Type Shipments Destination A Poly HIC* 0

B Poly HIC* 3 Waste Control

a. Resin/filters Specialists, C Poly HIC* 0 Andrews, TX

b. Dry active waste A General Design 5

• High Integrity Container

B. Irradiated Fuel Shipments (Disposition)

Number of Shipments Mode of Transportation Destination 0 N/A N/A

Page 43 of 57 TXX-24023 Enclosure Page 44 of 57

Attachment 10.1 Meteorological Joint Frequency Distribution Tables

Page 44 of 57 TXX-24023 Enclosure Page 45 of 57

Reg. Guide 1.21 Joint Frequency Table

CPNPP

HOURS AT EACH WIND SPEED AND DIRECTION

PERIOD OF RECORD: 1-JAN-2023 00:00 to 31-DEC-2023 23:59

STABILITY CLASS A

ELEVATION:

10 m

WIND Wind Speed (mph)

DIRECTION 1-3 4-7 8-12 13-18 19-24 >24 TOTAL N 0 3760016 NNE 0 12 23 3 0 0 38 NE 1 20 8 0 0 0 29 ENE 5291000044 E 1 32 17 4 0 0 54 ESE 0 52 77 1 0 0 130 SE 0 28 47 4 0 0 79 SSE 0 39 124 31 1 0 195 S 219852320131 SSW 0 13 33 13 0 0 59 SW 091610026 WSW 0 480001 2 W 0 6430013 WNW 0 10000 1 NW 0 149101 5 NNW 0 4 21 30 11 0 66 VARIABLE 0 687002 1 TOTAL 9 278 492 135 15 0 929

Page 45 of 57 TXX-24023 Enclosure Page 46 of 57

Reg. Guide 1.21 Joint Frequency Table

CPNPP

HOURS AT EACH WIND SPEED AND DIRECTION

PERIOD OF RECORD: 1-JAN-2023 00:00 to 31-DEC-2023 23:59

STABILITY CLASS B

ELEVATION:

10 m

WIND Wind Speed (mph)

DIRECTION 1-3 4-7 8-12 13-18 19-24 >24 TOTAL N 0313007 NNE1642001 3 NE2420008 ENE 0810009 E 0 11 4 1 0 0 16 ESE 1272220052 SE 0 21 27 4 0 0 52 SSE 0 19 31 16 1 0 67 S 01132268077 SSW1519141040 SW 07640017 WSW 0 6 5 2 0 0 13 W 0734001 4 WNW 0 1 1 0 0 0 2 NW0195101 6 NNW 0 7 18 14 6 0 45 VARIABLE 14320010 TOTAL 6 148 188 99 17 0 458

Page 46 of 57 TXX-24023 Enclosure Page 47 of 57

Reg. Guide 1.21 Joint Frequency Table

CPNPP

HOURS AT EACH WIND SPEED AND DIRECTION

PERIOD OF RECORD: 1-JAN-2023 00:00 to 31-DEC-2023 23:59

STABILITY CLASS C

ELEVATION:

10 m

WIND Wind Speed (mph)

DIRECTION 1-3 4-7 8-12 13-18 19-24 >24 TOTAL N 0 05200 7 NNE 1 984002 2 NE 3 9 6 1 0 0 19 ENE 4 8600018 E 52153003 4 ESE 3381400055 SE 3 23 15 3 0 0 44 SSE 4 20 35 23 3 0 85 S 21133317084 SSW 1 13 27 19 1 0 61 SW 01215141244 WSW 0 10 9 4 0 0 23 W 0 7330013 WNW 0 35100 9 NW 0 7 14 19 4 0 44 NNW 0916125446 VARIABLE 0 3530011 TOTAL 26 203 221 142 21 6 619

Page 47 of 57 TXX-24023 Enclosure Page 48 of 57

Reg. Guide 1.21 Joint Frequency Table

CPNPP

HOURS AT EACH WIND SPEED AND DIRECTION

PERIOD OF RECORD: 1-JAN-2023 00:00 to 31-DEC-2023 23:59

STABILITY CLASS D

ELEVATION:

10 m

WIND Wind Speed (mph)

DIRECTION 1-3 4-7 8-12 13-18 19-24 >24 TOTAL N 0 25 74 18 1 0 118 NNE 4 23 66 14 0 0 107 NE 14 41 42 9 0 1 107 ENE 9 38 37 1 0 0 85 E 20 133 55 2 0 0 210 ESE 19 208 66 0 0 0 293 SE 26 158 191 15 0 0 390 SSE 16 100 339 147 15 0 617 S 13 6826612815 0 490 SSW 11 4272402 0 167 SW 8 3534314 1 113 WSW 3 3522112 0 73 W 4 28 22 9 1 0 64 WNW 2 19 38 23 2 0 84 NW 7 285041134 143 NNW 5 42 110 134 20 0 311 VARIABLE 12 36 30 4 0 0 82 TOTAL 173 1059 1514 627 75 6 3454

Page 48 of 57 TXX-24023 Enclosure Page 49 of 57

Reg. Guide 1.21 Joint Frequency Table

CPNPP

HOURS AT EACH WIND SPEED AND DIRECTION

PERIOD OF RECORD: 1-JAN-2023 00:00 to 31-DEC-2023 23:59

STABILITY CLASS E

ELEVATION:

10 m

WIND Wind Speed (mph)

DIRECTION 1-3 4-7 8-12 13-18 19-24 >24 TOTAL N 1 610008 NNE 4 23 5 100 33 NE 1 730001 1 ENE 412410021 E25662000 93 ESE 6112380001 92 SE 49 350 115 1 00 515 SSE 33 185 226 7 1 0 452 S 28 87 56 5 0 0 176 SSW 29 47 45 10 20 133 SW 20 24 35 8 5 0 92 WSW 17 23 19 3 00 62 W 8211230044 WNW 12 39 16 4 00 71 NW 11 63 52 3 0 0 129 NNW 31980003 0 VARIABLE 23 14 1 1 0 039 TOTAL 329 1109 608 47 8 0 2101

Page 49 of 57 TXX-24023 Enclosure Page 50 of 57

Reg. Guide 1.21 Joint Frequency Table

CPNPP

HOURS AT EACH WIND SPEED AND DIRECTION

PERIOD OF RECORD: 1-JAN-2023 00:00 to 31-DEC-2023 23:59

STABILITY CLASS F

ELEVATION:

10 m

WIND Wind Speed (mph)

DIRECTION 1-3 4-7 8-12 13-18 19-24 >24 TOTAL N 000000 0 NNE 000000 0 NE 000000 0 ENE 000000 0 E10 0000 1 ESE 78100016 SE 14 73 3 0 0 090 SSE 121920003 3 S 222440005 0 SSW 29 33 13 0 0 0 75 SW 2318900050 WSW 24 22 8 0 0 054 W 1212400028 WNW 9 13 1 0 0 023 NW 6 23 5 0 0 0 34 NNW 000000 0 VARIABLE 171000 018 TOTAL 176 246 50 0 0 0 472

Page 50 of 57 TXX-24023 Enclosure Page 51 of 57

Reg. Guide 1.21 Joint Frequency Table

CPNPP

HOURS AT EACH WIND SPEED AND DIRECTION

PERIOD OF RECORD: 1-JAN-2023 00:00 to 31-DEC-2023 23:59

STABILITY CLASS G

ELEVATION:

10 m

WIND Wind Speed (mph)

DIRECTION 1-3 4-7 8-12 13-18 19-24 >24 TOTAL N 1 00000 1 NNE 0 00000 0 NE 0 00000 0 ENE 0 00000 0 E 0 00000 0 ESE 2 0 0 000 2 SE 6 3 0 000 9 SSE 3 20000 5 S 9 12 0 000 21 SSW 22 8 2 000 32 SW 21 26 7 000 54 WSW 16 33 16 000 65 W860 000 14 WNW 5 1 1 000 7 NW 0 40000 4 NNW 0 00000 0 VARIABLE 5 2 0 000 7 TOTAL 98 97 26 000 221

Page 51 of 57 TXX-24023 Enclosure Page 52 of 57

Reg. Guide 1.21 Joint Frequency Table

CPNPP

HOURS AT EACH WIND SPEED AND DIRECTION

PERIOD OF RECORD: 1-JAN-2023 00:00 to 31-DEC-2023 23:59

STABILITY CLASS ALL

ELEVATION:

10 m

WIND Wind Speed (mph)

DIRECTION 1-3 4-7 8-12 13-18 19-24 >24 TOTAL N 2 3788291 0 157 NNE 10 73 106 24 0 0 213 NE 21 81 61 10 0 1 174 ENE 22 95 58 2 0 0 177 E 52 263 83 10 0 0 408 ESE 93 456 188 3 0 0 740 SE 98 656 398 27 0 0 1179 SSE 68 384 757 224 21 0 1454 S 76 232 476 213 32 0 1029 SSW 93 161 211 96 6 0 567 SW 72 131 122 58 10 3 396 WSW 60 133 87 20 2 0 302 W 32 87 48 22 1 0 190 WNW 28 77 62 28 2 0 197 NW 24 127 134 77 19 4 385 NNW 8 81 173 190 42 4 498 VARIABLE 58 66 47 17 0 0 188 TOTAL 817 3140 3099 1050 136 12 8254 Periods of calm (hours): 2 Hours of missing data: 11

Page 52 of 57 TXX-24023 Enclosure Page 53 of 57

Wind Rose and Stability Class Graphs

Page 53 of 57 TXX-24023 Enclosure Page 54 of 57

Attachment 10.2 Atmospheric Dispersion (X/Q) and Deposition (D/Q)

Calculation Methodology Discussion

Introduction

CR-2014-001059 evaluated the atmospheric dispersion (X/Q) and deposition (D/Q) calculation methodology and frequency as they relate to the meteorological data to ensure they are up to date. The CPNPP ODCM does not require a re-evaluation on any frequency or specific criteria for comparison. The NRC guidance documents cited in the ODCM also do not provide any requirements for re-evaluation. Revision 2 of Regulatory Guide 1.21, to which we are not committed, recommends that 5 years of meteorological data be used to evaluate the dispersion factors and that variation in the factors be within 10% in the non-conservative direction. The evaluation of our meteorological data included 6 years of data and meets the criteria.

Discussion

Meteorological data collected for the original FSAR, the NuBuild FSAR and historical Radiological Effluent Reports were reviewed. The data list the predominant wind direction, as a percentage, averaged for all speeds and stability classes within the period. For periods not summarized and when the plant was operable (1990-2000) only 1990, 1995 and 1996 show the predominant wind direction to be from the SSE. This information was not included, however, since the data should include a summary of at least 5 years of data. The original dispersion and deposition factors were calculated based on meteorological data collected and summarized from 1972 through 1976 at Comanche Peak. Data show the predominant wind direction to be from the South but only slightly more than winds originating from the SSE. The historical data from 1957-1976 was included in the original FSAR for comparison and show more bias toward the southerl y direction but was collected from the Dallas-Fort Worth Airport location. Wind patterns for the DFW Airport were reviewed on the National Weather Service website for 1981-2010 and show that the prevailing wind direction remains from the South.

This accounts for the slight variation in prevailing winds between historical and current data collected on site.

During the New Build project for Units 3&4 and from OE 25286 the meteorological data were again summarized from 1997-2006, for Comanche Peak, and showed that the predominant wind direction shifted to the SSE. Using this data, new dispersion and deposition factors were calculated. The new factors were less conservative when compared to the original dispersion and deposition factors at the Exclusion Area Boundary (See Reference 3). The conclusion was to continue reporting offsite exposures based on the original values.

The last column of data in Table 1 is summarized for the purposes of this evaluation and includes meteorological data since the New Build evaluation through 2012. This data, like the NuBuild data, show the predominant wind directi on to be from the SSE.

Conclusion

Although the predominant wind direction frequency changes slightly from SSE to S when comparing the NuBuild Data to the original FSAR and Historical Data, the NuBuild calculations show that dispersion and deposition factors do not increase. Following the NuBuild evaluation, the wind direction remains the same and does not impact the calculation of the dispersion and deposition. Using the original factors would be conservative when calculating dose to the public.

TR-2024-001329 was initiated to document the evaluation of prevailing wind directions for all stability classes over the calendar year 2023. This evaluation is performed annually in accordance with Chemistry Guideline 25 to ensure the predominant wind direction has not changed based on the last 5 years of meteorological data including the current year. The 2023 predominant wind direction (SSE) and stability class category (Pasquill Class D) did not change when compared with the five year rolling average which includes 2023. No recalculations of X/Q or D/Q values are required at this time.

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Attachment 10.3 Carbon-14 Supplemental Information

Carbon-14 (C-14) is a naturally occurring isotope of carbon produced by interactions with cosmic radiation in the atmosphere with a half-life of 5730 years. Nuclear weapons testing in the 1950s and 1960s significantly increased the amount of C-14 in the atmosphere. C-14 is also produced in commercial nuclear reactors, but the amounts are much less than the amounts produced from natural formation or from weapons testing.

In June 2009, the NRC provided revised guidance in Regulatory Guide 1.21, Measuring, Evaluating and Reporting Radioactive Material in Liquid and Gaseous Effluents and Solid Waste, Revision 2, establishing an updated approach for identifying principal radionuclides. Because the overall quantity of radioactive releases has steadily decreased due to improvements in power plant operations, C-14 now qualifies as a principal radionuclide (anything greater than one percent of overall radioactivity in effluents) under federal regulations at many plants. In other words, C-14 has not increased and C-14 is not a new nuclear plant emission. Rather, the improvements in the mitigation of other isotopes have made C-14 more prominent.

The dose contribution of C-14 from liquid radioactive waste is essentially insignificant compared to that contributed by gaseous radioactive waste. Therefore, the evaluation of C-14 in liquid radioactive waste is not required by the new Reg. Guide 1.21, Rev. 2. The Reg. Guide 1.21, Rev. 2 also states that the quantity of gaseous C-14 released to the environment can be estimated by use of a C-14 source term production model.

A recent study produced by EPRI ( Estimation of Carbon-14 in Nuclear Power Plant Gaseous Effluents, EPRI, Palo Alto, CA: 2010, 1021106) developed a model for estimation of C-14 source production. This model was used by CPNPP for the 2010 Radioactive Effluent Release Report. Also in the CPNPP report, the assumption that 70% of the C-14 gaseous effluent is estimated to be from batch releases (e.g. WGDTs), and 30% of C-14 gaseous effluent is estimated to be from continuous releases through the unit vents (Ref. IAEA Technical Reports Series no. 421, "Management of Waste Containing Tritium and Carbon-14", 2004).

The C-14 released from PWRs is primarily a mix of organic carbon and carbon dioxide released from the waste gas system. The C-14 species initially produced are primarily in the organic form, such as methane. The C-14 in the primary coolant can be converted to an inorganic chemical form of primarily carbon dioxide t hrough a chemical transformation. Studies documented by the EPRI Report Characterization of Carbon-14 Generated by the Nuclear Power Industry, EPRI Palo Alto, CA: 1995, TR-105715, measured C-14 releases from PWRs indicating a range of 70% to 95% organic. The average value was indicated to be 80% organic with the remainder being carbon dioxide. As a result, a value of 80% organic C-14 is assumed by the CPNPP Radioactive Effluent Release Report methodology.

The public dose estimates from airborne C-14 in the CPNPP Effluent report are performed using dose models from NUREG-0133 and Regulatory Guide 1.109. The dose models and assumptions used for the dose estimates of C-14 are documented in the 2011 ODCM changes. The estimated C-14 dose impact on the maximum organ dose from airborne effluents released during 2011 is well below the 10CFR50, Appendix I, ALARA design objective of 15 mRem/yr per unit.

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Attachment 10.4 Putting Radiation Dose in Context

Humans are exposed to radiation every day. The majority comes from natural sources including the earth, food and water consumption, t he air, the s un and outer space. A smaller fraction radiation comes from man-made source suc h as X-rays, nuclear m edical treatments, building materials, nuclear power pl ants, smoke detec tors and televisions.

Radiati on is measu red in units called millirem (mRem). One mRem is a ver y small amount of exposure. On average, Americans receive 620 mRem of radiation dose every year. Approximately one-half of the dose comes from natural sources and the other half comes from medical procedures such as CAT scans.

The table below can help to give some perspective to dose from various sources.

Source Average Annual Dose Smoke detector in the home 0.008 mRem Live within 50 miles of a nuclear power plant 0.009 mRem Live within 50 miles of a coal-fired power plant* 0.03 mRem NRC guideline for keeping radiation dose from nuclear power plants as low as reasonably achievable (ALARA) 5 mRem Round trip flight from New York City to Los Angeles 5 mRem Medical X-ray 10 mRem EPA limit for dose to the public from the commercial nuclear fuel cycle 25 mRem Food and water consumed throughout the course of one year 30 mRem NRC limit for dose to the public from nuclear power plants 100 mRem Mammogram 100 mRem Average annual exposure for a nuclear power plant worker 120 mRem Average annual exposure from background radiation 300 mRem CT scan 1,000 mRem NRCs annual limit for occupational exposure 5,000 mRem Cardiac catheterization or coronary angiogram 5,000 mRem

• Coal is naturally radioactive.

Sources: U.S. Environmental Protection Agency, Health Physics Society.

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Attachment 10.5 Errata from Previous Annual Radioactive Effluent Release Reports

1. The 2015 ARERR has a typographical error in Table 9.4 on page 30. The t otal tritium for the year was shown as 1.64e+01. It should have read 1.64E-01 Tritium value for the dose calculations was the correct value. AI-TR-2017-009339

2. The 2016 ARERR has an incorrect title on page 13 in the comments section. The title reads: Total Body Dose due to Gaseous Activity Released Comments and should read Total Volume Liquid Effluents Released Comments Comments in the box regarding the graph on page 13 were correct. IR-2018-001484

3. 2017 ARERR: p. 9-CPNPP should be added to Water Plant to clarify that it is the Comanche Peak water plant and not a public facility; p. 18-Comments Table should read Total Volume of Solid Radwaste Buried rather than Total Body Dose due to Liquid Effluents Released; p. 26-Third paragraph needs to be reworded for clarification. The 2018 ARERR was updated with these comments from TR-2019-000972.

4. 2020 ARERR: Liquid Effluents Table 9.6 on page 38 contains liquid effluent data per Unit vice per Site (exactly one-half of the Site values). However, Table 9.5, Liquid Effluents, Summation of All Releases data on page 37 is correct. Since dose contributions from liquid effluents is calculated using the summation values, dose values for liquid effluents are correct. The reporting error was limited to Table 9.6 and the Executive Summary for liquid effluents on page 8.

5. 2020 and 2021 ARERRs: Several post-release gaseous effluent permits used estimated vs. actual plant vent stack flow rates during 2020 and 2021. Plant vent stack (PVS) flow rates were estimated using the number of fans in service and summing their corresponding flow rates. This is an acceptable practice.

Normally, actual PVS flow rates are derived from plant computer data. However, during these times, the actual values were unavailable when a part of the plant computer system was out of service. The impact to offsite calculated dose rates was insignificant since the only radioisotope released is usually tritium, and its activity is normally very low. This issue was documented in Comanche Peaks corrective action program (CR-2021-003323).

6. 2021 ARERR: During late 2022, plant vent stack flow rate typographical errors were found in two radiological gaseous effluent release permits generated and closed in 2021. These permits were reprocessed with the correct values and the affected tables were regenerated following the permit reprocessing. The corrections were evaluated to determine the impacts they had on gaseous tritium released and dose. Based on the evaluation, the corrections had only a minor impact on the amount of gaseous tritium released from the site during 2021 and revealed that total gaseous tritium released during 2021 was underreported by approximately 0.9%. However, the errors were not significant enough to change the dose contribution from tritium as reported in the 2021 ARERR. Therefore, the 2021 ARERR gaseous release dose values are correct (CR-2022-007381).

7. 2022 ARERR: At this time, no errata have been found in this report.

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