ML21118A832

Annual Radioactive Effluent Release Report (ARERR)

ML21118A832
Person / Time
Site:	Braidwood
Issue date:	05/01/2021
From:	Exelon Generation Co
To:	Office of Nuclear Material Safety and Safeguards, Office of Nuclear Reactor Regulation
Shared Package
ML21118A830	List: BW210028, CY-BR-170-301, Revision 11, Offsite Dose Calculation Manual (ODCM) ML21118A831 ML21118A832
References
BW210028
Download: ML21118A832 (95)

Text

2020 Braidwood Nuclear Power Station Annual Radioactive Effluent Release Report (ARERR)

UNIT 1 AND UNIT 2 (Docket Numbers 50-456 and 50-457)

ISFSI (Docket Number 72-73)

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

DOCUMENT INDEX Preface .....................................................................................................................................................2 Introduction................................................................................................................................................9 A. Supplemental Information ............................................................................................................9 B. Gaseous Effluents ........................................................................................................................16 C. Liquid Effluents .............................................................................................................................16 D. Radiological Impact on Man .........................................................................................................16 E. Meteorological Data .....................................................................................................................18 F. Offsite Ambient Radiation Measurements ...................................................................................18 G. Radioactive Solid Waste Disposal ...............................................................................................19 APPENDIX A: EFFLUENT AND WASTE DISPOSAL

SUMMARY

...........................................................20 APPENDIX B: SOLID WASTE AND IRRADIATED FUEL SHIPMENTS ..................................................30 APPENDIX C: WIND DIRECTION AND STABILITY CLASSES ..............................................................36 APPENDIX D: ERRATA ............................................................................................................................94 Page 1 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Preface The following sections of the preface are meant to help define key concepts, provide clarity, and give context to the readers of this report.

Annual Reports The Nuclear Regulatory Commission (NRC) is the federal agency who has the role to protect public health and safety through the development of regulations governing nuclear power reactors and ensuring their compliance. As part of the many commitments Nuclear Power Plants have to the NRC to ensure this safety, they provide two reports annually to specifically address how the stations operation impacts the environment of local communities. The NRC then reviews these reports and makes them available to the public. The names of the reports are the Annual Radioactive Effluent Release Report (ARERR) and the Annual Radiological Environmental Operating Report (AREOR).

The ARERR reports the results of the sampling from the effluent release paths at the station analyzed for radioactivity. An effluent is a liquid or gaseous waste containing plant-related radioactive material emitted at the boundary of the facility.

The AREOR reports the results of the samples obtained in the environment surrounding the station.

Environmental samples include air, water, vegetation, and other sample types that are identified as potential pathways radioactivity can reach humans.

Graphic 1. Examples of Gaseous and Liquid Effluent Pathways Graphic 1 demonstrates some potential exposure pathways from Braidwood Nuclear Power Station. The ARERR and AREOR together ensure Nuclear Power Plants are operating in a manner that is within established regulatory commitments meant to adequately protect the public.

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Understanding Radiation Generally radiation is defined as emitted energy in the form of waves or particles. If radiation has enough energy to displace electrons from an atom it is termed ionizing, otherwise it is non-ionizing. Non-Ionizing radiation includes light, heat given off from a stove, radiowaves and microwaves. Ionizing radiation occurs in atoms, particles too small for the eye to see. So, what are atoms and how does radiation come from them?

Graphic 2. Types of Radiation, from NASA Hubblesite An atom is the smallest part of an element that maintains the characteristics of that element. Atoms are made up of three parts: protons, neutrons, and electrons.

Graphic

3. Structure of an Atom The number of protons in an atom determines the element. For example, a hydrogen atom will always have one proton while an oxygen atom will always have eight protons. The protons are clustered with the neutrons forming the nucleus at the center of the atom. Orbiting around the nucleus are the relatively small electrons.

Isotopes are atoms that have the same number of protons but different numbers of neutrons. Different isotopes of an element will all have the same chemical properties and many isotopes are radioactive while other isotopes are not radioactive. A radioactive isotope can emit radiation because it contains excess energy in its nucleus.

Radioactive atoms and isotopes are also referred to as radionuclides and radioisotopes.

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There are two basic ways that radionuclides are produced at a nuclear power plant. The first is fission, which creates radionucides that are called fission products. Fission occurs when a very large atom, such as uranium-235 (U-235) or plutonium-239 (Pu-239), absorbs a neutron into its nucleus making the atom unstable. The unstable atom can then split into smaller atoms. When fission occurs there is a large amount of energy released, in the form of heat. A nuclear power plant uses the heat generated to boil water that spins turbines to produce electricity.

The second way a radionuclide is produced at a nuclear power plant is through a process called activation.

Radionuclides produced in this method are termed activation products. Pure water that passes over the fissioning atoms is used to cool the reactor and also produce steam to turn the turbines. Although this water is considered to be very pure, there are always some contaminants within the water from material used in the plants construction and operation. These contaminants are exposed to the fission process and may become activation products. The atoms in the water itself can also become activated and create radionuclides.

Over time, radioactive atoms will reach a stable state and no longer be radioactive. To do this they must release their excess energy. This release of excess energy is called radioactive decay. The time it takes for a radionuclide to become stable is measured in units called half-lives. A half-life is the amount of time it takes for half of the original radioactivity to decay. Each radionuclide has a specific half-life. Some half-lives can be very long and measured in years while others may be very short and measured in seconds.

Graphic 4. Radioactive Decay Half-Life In the annual reports you will see both man made and naturally ocurring radionuclides listed, for example potassium-40 (K-40, natural) and cobalt-60 (Co-60, man-made). We are mostly concerned about man-made radionuclides because they can be produced as by-products when generating electricity at a nuclear power plant. It is important to note that there are also other ways man-made radionuclides are produced, such as detonating nuclear weapons. Weapons testing has deposited some of the same man-made radionuclides into the environment as those generated by nuclear power, and some are still present today because of long half-lives.

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BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Measuring Radiation There are four different but interrelated units for measuring radioactivity, exposure, absorbed dose, and dose equivalent. Together, they are used to scientifically report the amount of radiation and its effects on humans.

• Radioactivity refers to the amount of ionizing radiation released by a material. The units of measure for radioactivity used within the AREOR and ARERR are the Curie (Ci). Small fractions of the Ci often have a prefix, such as the microcurie (Ci), which means 1/1,000,000 of a Curie.

• Exposure describes the amount of radiation traveling through the air. The units of measure for exposure used within the AREOR and ARERR are the Roentgen (R). Traditionally direct radiation monitors placed around the site are measured milliRoentgen (mR), 1/1,000 of one R.

• Absorbed dose describes the amount of radiation absorbed by an object or person. The units of measure for absorbed dose used within the AREOR and ARERR are the rad. Noble gas air doses are reported by the site are measured in millirad (mrad), 1/1,000 of one rad.

• Dose equivalent (or effective dose) combines the amount of radiation absorbed and the health effects of that type of radiation. The units used within the AREOR and ARERR are the Roentgen equivalent man (rem). Regulations require doses to the whole body, specific organ, and direct radiation to be reported in millirem (mrem), 1/1,000 of one rem.

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Sources of Radiation People are exposed to radiation every day of their lives and have been since the dawn of mankind. Some of this radiation is naturally occurring while some is man-made. There are many factors that will determine the amount of radiation individuals will be exposed to such as where they live, medical treatments, etc. The average person in the United States is exposed to approximately 620 mrem each year. Half of this exposure, 310 mrem, comes from natural sources and the other half, 310 mrem, from man-made sources. Graphic 5 shows what the typical sources of radiation are for an individual over a calendar year:

Graphic 5. Sources of Radiation Exposure in the U.S., from NCRP Report No. 160 The radiation from a nuclear power plant is included in the chart as part of the Industrial and Occupational fraction, <0.1%. The largest natural source of radiation is from radon, because radon gas travels in the air we breathe. Perhaps you know someone who had a CT scan at a hospital to check his or her bones, brain, or heart. CT scans are included in the chart as Medical Procedures which make up the next largest fraction.

Graphic 6 on the following page shows some of the common doses humans receive from radiation every year.

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Graphic 6 .Relative Doses from Radiation Sources, from EPA Radiation Doses and Sources Page 7 of 94

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Radiation Risk Current science suggests there is some risk from any exposure to radiation. However, it is very hard to tell whether cancers or deaths can be attributed to very low doses of radiation or by something else. U.S. radiation protection standards are based on the premise that any radiation exposure carries some risk.

The following graph is an example of one study that tries to relate risk from many different factors. This graph represents risk as Days of Lost Life Expectancy. All the categories are averaged over the entire population except Male Smokers, Female Smokers, and individuals that are overweight. Those risks are only for people that fall into those categories. The category for Nuclear Power is a government estimate based on all radioactivity releases from nuclear power, including accidents and wastes.

Graphic 7. Days of Lost Life Expectancy, Adapted from the Journal of American Physicians and Surgeons Volume 8 Number 2 Summer 2003 Page 8 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Introduction This report quantifies the radioactive gaseous, liquid, solid radioactive waste (radwaste) releases, and summarizes the local meteorological data for the period from January 01, 2020 through December 31, 2020.

This report has been prepared utilizing the methodology and parameters specified in the calculation of offsite doses resulting from radioactive gaseous and liquid effluents found in Braidwoods Offsite Dose Calculation Manual (ODCM). It has been formatted consistent with Exelon Procedure CY-AA-170-2000 ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT as well as the requirements specified in Regulatory Guide 1.21 Revision 1, MEASURING, EVALUATING, AND REPORTING RADIOACTIVITY IN SOLID WASTES AND RELEASES OF RADIOACTIVE MATERIALS IN LIQUID AND GASEOUS EFFLUENTS FROM LIGHT-WATER-COOLED NUCLEAR POWER PLANTS.

The quantity of radioactive material released from Braidwood Nuclear Power Plant was determined from in-house and vendor laboratory analysis of continuous inline sampling media and batch sample media from all ODCM specified effluent pathways. These pathways include continuous releases from the Unit 1 and Unit 2 Station Vent Stack, Condensate Polisher Sump, Waste Water Treatment, and Circulating Water Blowdown.

The ODCM specified effluent pathways also include batch releases from the Unit 1 and Unit 2 Primary Containments, Waste Gas Decay Tanks, and Liquid Radwaste Batch Release Tanks.

The volume and quantity of radioactive waste shipped offsite from Braidwood Nuclear Power Plant for processing and disposal was determined from data maintained in the radwaste shipping database. Radwaste processed for shipment was in accordance with Exelon procedure RW-AA-100, PROCESS CONTROL PROGRAM FOR RADIOACTIVE WASTES and consistent with the UFSAR.

Meteorological data was obtained from the 320-foot meteorological tower located on the Braidwood Station premises.

A. Supplemental Information

1. Regulatory Limits

a. Fission and Activation Gases:

Dose Rate

1) Less than 500 mrem/year to the whole body (instantaneous limit, per site).

2) Less than 3,000 mrem/year to the skin (instantaneous limit, per site).

Dose Gamma Radiation

1) Less than or equal to 5 mrad/quarter (per unit).

2) Less than or equal to 10 mrad/year (per unit).

Dose Beta Radiation

1) Less than or equal to 10 mrad/quarter (per unit).

2) Less than or equal to 20 mrad/year (per unit).

b. Iodine: (summed with particulate, see below)

c. Particulates with half-lives > 8 days:

Dose Rate

1) Less than 1,500 mrem/year to any organ (instantaneous limit, per site).

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Dose

1) Less than or equal to 7.5 mrem/quarter to any organ (per unit).

2) Less than or equal to 15 mrem/year to any organ (per unit).

d. Liquid Effluents Dose

1) Less than or equal to 1.5 mrem to the whole body during any calendar quarter (per unit).

2) Less than or equal to 5 mrem to any organ during any calendar quarter (per unit).

3) Less than or equal to 3 mrem to the whole body during any calendar year (per unit).

4) Less than or equal to 10 mrem to any organ during any calendar year (per unit).

2. Effluent Concentration Limits

a. Fission and Activation Gases: 10CFR20 Appendix B Table 2

b. Iodine: 10CFR20 Appendix B Table 2

c. Particulates: 10CFR20 Appendix B Table 2

d. Liquid Effluents: 10 X 10CFR20 Appendix B Table 2

3. Average Energy The ODCM limits the dose equivalent rates due to the release of noble gases to less than or equal to 500 mrem/yr to the total body, and less than or equal to 3,000 mrem/yr to the skin. Therefore, the average beta and gamma energies () for gaseous effluents as described in Regulatory Guide 1.21 are not applicable.

4. Measurements and Approximations of Total Radioactivity

a. Fission and activation gases:

Before being discharged, containment batch releases are analyzed for noble gas via gamma spectroscopy. Gaseous decay tanks are analyzed for noble gases before being discharged via gamma spectroscopy. Released activity is normally calculated using volume of release, which is determined by purge flow rate, times the duration of the discharge.

The Auxiliary Building ventilation exhaust system is continually monitored for radioactive iodines (radioiodines) and particulates. These samples are obtained every seven days and analyzed via gamma spectroscopy.

Noble gas samples are obtained and analyzed weekly by gamma spectroscopy. The average flow at the release points and nuclide specific activity concentrations are used to calculate the activity released.

Volumes and activities of effluents discharged from systems that are common to both units are divided between both units.

b. Iodines:

Radioiodines in the Auxiliary Building ventilation exhaust system are continually being collected via activated charcoal cartridges in the diverted sample process flow. The iodine cartridges are pulled weekly and analyzed via gamma spectroscopy. Radioiodine concentrations greater than the lower limit of detection (LLD) are multiplied by the volume of air discharged during the sampling timeframe.

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Radioiodines are analyzed in liquid effluent streams through performance of batch release tank grab samples and weekly liquid effluent composite samples. The analyses are performed via gamma spectroscopy of the liquid samples.

Volumes and activities of effluents discharged from systems that are common to both units are divided between both units. Effluents that are unit specific are assigned to the appropriate unit.

c. Particulate, half-lives > 8 days:

Particulates in the Auxiliary Building ventilation exhaust system are continually being collected via filter media in the diverted sample process flow. Particulate filter media is pulled weekly and analyzed via gamma spectroscopy. Particulate concentrations greater than LLD are multiplied by the volume of air discharged during the sampling timeframe. A composite sample is created from 3 months particulate sample media for Sr-89/90, Fe-55, Ni-63, and gross alpha analysis by an offsite vendor. The vendor supplied data is utilized in conjunction with the volume of air released through the Auxiliary Building ventilation to quantify Sr-89/90, Fe-55, Ni-63, and gross alpha releases.

Volumes and activities of effluents discharged from systems that are common to both units are divided between both units. Effluents that are unit specific are assigned to the appropriate unit.

d. Tritium:

Before being discharged, containment batch releases are analyzed for tritium via a liquid scintillation counter (LSC). Tritium is sampled using a flow-through bubbler system. Released activity is calculated using volume of release, which is determined by purge flow rate multiplied by the duration of the discharge.

The Auxiliary Building ventilation exhaust system is monitored for tritium using a flow-through bubbler system. Tritium is sampled every seven days and analyzed by LSC.

The secondary sides of both units contain tritium. Minimal amounts of tritium are continually released to the atmosphere from secondary components through packing leaks, tank vents, the main condenser, etc. Bounding calculations have been performed to show that large leaks (1000 gallons/day (gpd)) for extended periods (1 month) at normal secondary tritium concentrations would provide an insignificant increase (1.00E-5 mrem) in offsite dose.

e. Gross alpha Gross alpha is analyzed in both the gaseous and liquid effluent pathways. Weekly gaseous particulate media is composited for offsite vendor analysis. Gross alpha activity greater than vendor LLD values are assigned to the applicable timeframe and gaseous volume released. Liquid effluent gross alpha analysis is performed through compositing monthly discharges and gas flow proportional counting.

f. Carbon-14 Carbon-14 (C-14) is assessed in continuous gaseous effluents using Electric Power Research Institutes (EPRI) industry accepted production mechanism and production rate study 1021106. C-14 production is a function of each units full power operation and gaseous volume released. C-14 is not evaluated through laboratory sample analysis.

g. Liquid effluents:

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Liquid effluents are categorized as either batch release or continuous release. All liquid releases are analyzed for principal gamma emitters, radioiodines, dissolved and entrained gases, gross alpha, and tritium onsite via gamma spectroscopy, gas flow proportional counting, or liquid scintillation, as appropriate. An offsite laboratory analyzes liquid composites for Sr-89/90, Fe-55 and Ni-63. Vendor results are applied to the applicable volume of liquids discharged during the timeframe. Volumes and activities of effluents discharged from systems or locations are divided between both units.

h. Estimated Total Error Present Procedure CY-AA-170-2100, Estimated Errors of Effluent Measurements provides the methodology to obtain an overall estimate of the error associated with radioactive effluents.

Estimated total error is calculated periodically and communicated as part of Appendix A Effluent and Waste Disposal Summary.

i. Lower Limit of Detection (LLD)

Samples are analyzed such that the Offsite Dose Calculation Manual (ODCM) LLD requirements are met. When a nuclide is not detected during the quarter then <LLD is reported. The ODCM required lower limit of detection for airborne and liquid releases are as follows:

Table 4.i ODCM Effluent LLD Values Airborne: LLD Gross Alpha, Sr-89, Sr-90 1.00E-11 µCi/cc H-3 1.00E-07 µCi/cc I-131 in Charcoal Samples 1.00E-12 µCi/cc I-133 in Charcoal Samples 1.00E-10 µCi/cc Principal Gamma Emitters (Mn-54, Fe-59, Co-58, Co-60, Zn-65, Mo-99, Cs-134, Cs-137, I-131, Ce-141, Ce-144) in Grab Samples 1.00E-04 µCi/cc Principal Gamma Emitters (Mn-54, Fe-59, Co-58, Co-60, Zn-65, Mo-99, 1.00E-11 µCi/cc Cs-134, Cs-137, I-131, Ce-141, Ce-144) in Particulate Samples Noble Gas (Kr-87, Kr-88, Xe-133, Xe-133m, Xe-135, Xe-138), Gross Beta or Gamma 1.00E-06 µCi/cc Table 4.i ODCM Effluent LLD Values (continued)

Liquid: LLD Principal Gamma Emitters except Ce-144 (Mn-54, Fe-59, Co-58, Co- 5.00E-07 µCi/ml 60, Zn-65, Mo-99, Cs-134, Cs-137, Ce-141)

Ce-144 5.00E-06 µCi/ml I-131 1.00E-06 µCi/ml Entrained Gases (Kr-87, Kr-88, Xe-133, Xe-133m, Xe-135, Xe-138) 1.00E-05 µCi/ml H-3 1.00E-05 µCi/ml Gross Alpha 1.00E-07 µCi/ml Sr-89, Sr-90 5.00E-08 µCi/ml Fe-55 1.00E-06 µCi/ml This list does not mean that only these nuclides are considered, but this list is used to ensure acceptable detection standards. Braidwood tests and maintains LLD records in accordance with procedure CY-AA-130-201 Radiochemistry Quality Control.

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BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

5. Batch Releases

a. Liquid Batch Releases 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr Annual

1. Total Number of Batch Releases 14 31 12 10 67

2. Total Time Period for Batch Releases (minutes) 2.235E+04 6.171E+04 2.391E+04 4.199E+04 1.499E+05

3. Maximum Time Period for a Batch Release (minutes) 2.917E+03 5.913E+03 4.920E+03 9.147E+03 9.147E+03

4. Average Time Period for a Batch Release (minutes) 1.596E+03 1.991E+03 1.992E+03 4.199E+03 2.238E+03

5. Minimum Time Period for a Batch Release (minutes) 4.970E+02 1.254E+03 9.120E+02 6.930E+02 4.970E+02

6. Average Stream Flow During Periods of Release 1.63E+07 1.61E+07 3.22E+06 1.96E+06 9.07E+06 of Effluent into a Flowing Stream (Liters/min) 1

b. Gaseous Batch Releases 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr Annual

1. Total Number of Batch 78 78 77 85 318 Releases

2. Total Time Period for 6.146E+03 1.806E+04 2.776E+04 4.961E+04 1.016E+05 Batch Releases (minutes)

3. Maximum Time Period for 1.513E+03 2.945E+03 1.874E+03 4.240E+03 4.240E+03 a Batch Release (minutes)

4. Average Time Period for 7.879E+01 2.316E+02 3.605E+02 5.836E+02 3.194E+02 a Batch Release (minutes)

5. Minimum Time Period for 2.200E+01 2.200E+01 1.900E+01 2.000E+01 1.900E+01 a Batch Release (minutes)

6. Abnormal Releases There were no abnormal gaseous releases that occurred in 2020.

7. Non-Routine, Planned Discharges There was one non-routine, planned discharge in 2020. G-20201214-899-B was approved for Hi-Trac painting in the Fuel Handling Building in December 2020.

8. Radioactive Waste Treatment System Changes There were no changes to the gaseous radioactive waste treatment system, the ventilation exhaust treatment system, or the liquid radioactive waste treatment system in 2020.

1 Kankakee River Flows obtained from US Geological Survey website from daily average flow data.

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9. Changes to the Annual Land Use Census The 2020 Land Use Survey was performed on August 29th, 2020.

10. Radioactive Effluent Monitoring Instrumentation out of service for more than 30 Days

a. On 11/16/2020 at 11:20am, 0RE-PR010 was inoperable for 30 days. 0RE-PR010 has been inoperable due to clearance order 00-CW-CWBDOOS-003 for CW Blowdown line inspections IR 04383819

b. Due to required parts acquisition delays, 2PR01J was in RETS for greater than the required restoration time (7 days) as of 12:04am on 10/3/20. IR 04374015

c. Due to CW blowdown being drained/inspected, 0PR01J and 0PR90J were in RETS for greater than the required restoration time (14 days) as of 1120 on 10/31/20. IR 04380050

11. Revisions to the ODCM Revision 11 of CY-BR-170-301, Offsite Dose Calculation Manual was completed in October 2020.

12. Independent Spent Fuel Storage Installation (ISFSI)

An Independent Spent Fuel Storage Installation (ISFSI) was placed in service at Braidwood Station in 2011. The ISFSI is a closed system and the only exposure would be due to direct radiation, which is measured by Optically Stimulated Luminescent Dosimetry (OSLD). In 2020 the dose to the nearest resident from the ISFSI was estimated to be 3.3E-01 mrem. This estimate was determined using environmental dosimeters from the Radiological Environmental Monitoring Program and extrapolating the dose from the ISFSI environmental dosimeters.

13. ERRATA (Appendix D)

a. CWBD Post Release Permit Adjustment An error was identified with the tritium activity in permt L-20190528-052. IR 04368302

b. Issues Identified with OpenEMS. An analysis with Mirion Technologies determined the effluent program, OpenEMS, was not calculating dose in accordance with the Braidwood ODCM. IR 04353041

14. Sampling and Instrumentation Issues

a. The ODCM compositor for the condensate polisher sump was not pulling the proper aliquot. The was consistently 4.5 gallons full each week, which caused a safety concern because it weighed over 40lbs. When a calibration was performed, the sample amount showed that it was adjusted correctly.

After exiting the calibration screen exits, it did not store the change. The compositor also collects sample during the rinsing cycle when it should have been expelling samples during that process. The rinse process provides no value and was functioning only to add additional water to the compositor jug, so the rinse cycle was disabled. The compositor is now collecting the appropriate volume of condensate polisher sump water. IR 04314950

b. While preparing the shipment of U-1/2 PR28J and PR29J second quarter air particulate sample filters to be shipped for offsite analysis, it was discovered that there was not a U1 air particulate sample filter for the time frame of 5/11/2020 1257 to 5/12/2020 0105. All the sample filters and their Page 14 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

IDs were immediately sorted and reviewed again. This second review and a search of the filter storage container, trash can, and surrounding area did not turn up the missing sample filter. A review of the results of the gamma isotopic analysis performed on the missing sample filter (when the missing filter had been removed from service) indicated that the particulate nuclides were all less than LLD. At some point after the gamma isotopic analysis, the sample filter was lost or discarded.

This missing filter and the associated volume was not part of the U1 quarterly composite sent to Teledyne Brown Engineering for the difficult to measure nuclides analysis. IR 04356971

c. While performing Inside Rover Rounds, the reading from 0FQ-TR046 (Clean Water Effluent Totalizer, 0TR01J in Waste Treatment Building) was found to be reading 2058280 Gallons. This was the same reading that was recorded on the previous shift, indicating 0 gallons of process flow. This is clearly not the case as TR was set to process to the Lake at 1700 on 3/1/20 and Lagoon Levels have lowered since then (Level is measured from the top, therefore a higher reading indicates level has gone down in the Lagoon). It appears that the totalizer stopped advancing between 2/25/20 and 2/26/20.

TR was on Recirc from 2/28/20 at 0211 until 3/1/20 at 1700 when it was realigned to the Lake. The totalizer should continue to advance even when aligned for Recirc (to EQ Tank). 0FT-TR046 (Flow Transmitter) is shown being upstream of 0TR081 and 0TR082 in print M-85 Sheet 3, C6.

Locally, flow was indicated at 0FI-TR046 (Flow Indicator) reading 100gpm (after the 12.5 multiplier) with the Clean Water Pump Running and the totalizer was observed not advancing at that time. The Field Supervisor and Chemistry were immediately informed of this condition. IR 04322982

e. While performing the weekly check of the ODCM condensate polisher compositor, it was noticed that there was no water in the compositor bottle. Initially the compositor was found on and the program indicated running. The hoses were walked down to verify that nothing had come lose or had any holes were present. While a grab sample was being performed in order to check to make sure the pump was working appropriately, the screen on the compositor went dark and no power was on.

The power cord was checked, and it appeared that the plug was not pushed in all of the way causing a loss of power. Once the cord was plugged in the power to the compositor came back on. The GFCI was verified and a grab sample was taken. The program was then resumed to obtain normal sampling frequency. IR 04319645

f. The CWBD compositor collects CWBD samples into its collection jug multiple times each day. On each Monday or Tuesday, the CWBD compositor is sampled, and this becomes the weekly CWBD composite sample. On the first Monday or Tuesday of each month, the final weekly composite for the preceding month is collected, and the preceding months weekly composites are combined to become the monthly CWBD composite sample. The previous methodology compared the CWBD monthly compositor sample that overlapped adjacent months to the release tank tritium curies for the calendar month. If the CWBD monthly composite sample multiplied by the volume of CWBD in a calendar month had a higher tritium activity than that of the release tanks, the difference was attributed to CWBD by creating a permit in OpenEMS for the remaining curies of tritium.

Release tanks are the only significant source of tritium input to the CWBD line. An extra week in the monthly composite period that overlaps an adjacent month, in conjunction with release tank discharge(s) in the adjacent month(s) create instances where the CWBD compositor sampling period (e.g., 5-28-2019 1130 to 7-1-2019 1330) has inputs from release tank discharges spanning one to three calendar months. This creates a condition where the CWBD compositor has a higher tritium activity from a longer sampling period than the total release tanks for the compared single calendar month. The mismatch in timing of release tanks and the CWBD monthly composite samples results in an overly conservative accounting of the tritium released in the blowdown line.

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In order to align the monthly CWBD and release tank permit comparison, the period for the release tanks compared on a monthly basis will match the period of the CWBD monthly composite.

Alignment with the release times will also align the tritium reporting resulting in more accurate reporting. Release tanks that cross over two CWBD monthly composite periods will be prorated based on total release time. A percentage of the release will be attributed to each monthly composite period so that there is no overlap. IR 04377245 B. Gaseous Effluents Gaseous radioactive releases for 2020 captured in Tables 1A, 1B-1, and 1B-2 in Appendix A for Units 1 and 2 combined. Radioactive noble gases released for the timeframe totaled 2.476E+00 Curies.

Releases of all radioiodines, halogens, and particulates totaled 1.47E-03 Curies. Gaseous tritium releases totaled 8.288E+01 Curies. Gaseous carbon-14 was calculated to total 8.544E+00 Curies. No gross alpha was detected in gaseous effluents.

C. Liquid Effluents Liquid radioactive releases for 2020 are captured in Tables 2A, 2B-1, and 2B-2 in Appendix A for Units 1 and Unit 2 combined. Sixty-seven (67) liquid batch releases occurred during the reporting period.

The continuous and batch release discharges contained a total of 1.910E+03 Curies of tritium and 7.188E-02 Curies of fission and activation products. No dissolved or entrained gases, and no gross alpha was detected in the liquid effluents.

D. Radiological Impact on Man

1. Dose to Members of the Public at or Beyond Site Boundary Per ODCM Chapter 6.1 the Annual Radioactive Effluent Release Report shall include an assessment of radiation doses to the hypothetically highest exposed MEMBER OF THE PUBLIC from reactor releases, ISFSI and other nearby uranium fuel cycle sources. This includes doses from primary effluent pathways and direct radiation for the previous calendar year. The ODCM does not require population doses to be calculated. For purposes of calculation, the following assumptions were made per the ODCM:

• Long term annual average meteorology X/Q and D/Q and actual gaseous effluent releases were used.

• Gamma air dose, Beta air dose, Total Body and Skin doses were attributed to noble gas releases.

• Critical organ and age group dose attributed to iodine, particulate, carbon-14 and tritium releases.

• A 0.7 shielding factor was assumed to account for shielding due to occupancy of structures

• Doses, Design Objective Limit, and Dose Limit comparisons reported combined for the site for both Unit 1 and Unit 2 together.

• Dosimetry measurements obtained from the highest station values in the Radiological Environmental Monitoring Program were used to calculate dose to the nearest residence from the Independent Spent Fuel Storage Installation (ISFSI). The dose measured at the station was extrapolated to the residence location.

• The highest doses from the critical organ and critical age group for each release pathway was summed and added to the net dosimetry measurement from nearest residence to the ISFSI for 40CFR190 and 10CFR72.104 dose compliance.

• Evaluation of 40CFR190 and 10CFR72.104 dose is used to demonstrate compliance to 10CFR 20 and satisfy station RETS and Technical Specifications.

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a. Gaseous Releases Calculated total body dose was 3.43E-01 mrem.The critical age-organ was the child-bone and the organ dose was 1.66E+00 mrem.

b. Liquid Releases Calculated total body dose was 1.65E-01 mrem. The critical age-organ was the child-GI-LLI and the organ dose was 1.74E-01 mrem.

c. 40CFR190 and 10CFR72.104 Compliance The Braidwood ODCM defines the total dose for the uranium fuel cycle as the sum of doses due to radioactivity in airborne and liquid effluents and the doses due to direct radiation from contained sources at the nuclear power station (ODCM A.4.2 Total Dose, Equation A-24). The total dose,

, in the unrestricted area to a member of the public due to plant operations is given by:

= + +

Where:

Total Dose to Member of Public [mrem]

Total off-site dose to a member of public due to plant operations.

Total External Total Body Dose [mrem]

Total body dose due to external exposure to noble gases, N-16 skyshine and on-site storage facilities.

Liquid Effluent Dose [mrem]

Dose due to liquid effluents to age group a and organ j. The age group and organ with the highest dose from liquid effluents is used.

Non-Noble Gaseous Effluent Dose [mrem]Dose due to non-noble gaseous effluents to age group a and organ j. The age group and organ with the highest dose from non-noble gas effluents is used.

The maximum calculated dose to a real individual would not exceed 8.38E-01 mrem (total body),

2.16E+00 mrem (organ), or 8.38E-01 mrem (thyroid).

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BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Table D.1 Summary of Gaseous and Liquid Effluent Doses to Members of the Public at the Highest Dose Receptors vs 10 CFR50 Design Objectives Design

% of Objective Maximum Individual Applicable Estimated Age Applicable Limit Unit Noble Gas Dose Dose Group Limit (per year, combined)

Nearest Residence Gamma Air Dose 6.36E-04 All 2.12E-03 20 mrad Nearest Residence Beta Air Dose 6.41E-04 All 1.07E-03 40 mrad Nearest Residence Total Body 6.05E-04 All 4.03E-03 10 mrem Nearest Residence Skin 1.23E-03 All 2.73E-03 30 mrem Non-Noble Gas Nearest Residence Bone 1.66E+00 Child 3.69E+00 30 mrem Liquid Nearest Residence Total Body 1.65E-01 Child 2.75E+00 6 mrem Nearest Residence GI-LLI 1.74E-01 Child 8.68E-01 20 mrem Table D.2 Summary of Doses to Members of the Public at the Highest Dose Receptors for 40CFR190 and 10CFR72.104 Compliance Non- External  % of Highest Dose Noble Liquid Direct Total Applicable Limit Unit Receptors Gas Effluents Radiation Limit Total Body Dose 3.43E-01 1.65E-01 3.30E-01 8.38E-01 3.35E+00 25 mrem Organ Dose 1.66E+00 1.74E-01 3.30E-01 2.16E+00 8.64E+00 25 mrem Thyroid Dose 3.44E-01 1.64E-01 3.30E-01 8.38E-01 1.12E+00 75 mrem E. Meteorological Data The Braidwood Station meteorological monitoring program produced 52,617 hours0.00714 days <br />0.171 hours <br />0.00102 weeks <br />2.347685e-4 months <br /> of valid data out of a possible 52,704 parameter hours during 2020 (365 days x 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />s/day x 6 measured priority parameters),

which represents an overall data recovery rate of 99.8%. Priority parameters are all parameters except dew point temperature and precipitation. For the year, winds measured at 34 ft. most frequently came from the West-Northwest (9.79) and fell into the 3.6 - 7.5 mph wind speed class (41.48%). Calms (wind speeds at or below the sensor threshold) were measured 0.00% of the time and speeds greater than 24.5 mph were measured 0.14% of the time. Stability based on the 199 - 30 ft. differential temperature most frequently fell into the neutral classification (45.14%).

Appendix C contains the Joint Frequency Distribution tables from the Meteorological Data collected in 2020.

F. Offsite Ambient Radiation Measurements Review of the Braidwood Optically Stimulated Luminescent Dosimetry (OSLD) data showed statistical increases above background at only locations related to the ISFSI pad. A dose evaluation was performed taking the highest readings and extrapolating dose to the nearest resident. The dose to the resident was estimated to be 3.30E-1 mrem in 2020.

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BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

G. Radioactive Solid Waste Disposal Radioactive wastes shipped offsite are captured in the table titled, Solid Wastes Shipped Offsite for Burial or Disposal (Not irradiated fuel). Approximately 2.23E+02 cubic meters of solid waste were shipped offsite containing approximately 2.90E+02 Curies during the 2020 reporting period. Appendix B contains tables and detailed information about the Solid Waste Disposal program.

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BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

APPENDIX A: EFFLUENT AND WASTE DISPOSAL

SUMMARY

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TABLE 1A GASEOUS EFFLUENTS- - SUMMATION OF ALL RELEASES UNIT 1 AND UNIT 2 Est. Total Unit 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr Annual Error%

A. Fission and Activation Gas Releases

1. Total Release Activity Ci 7.349E-02 2.637E-01 1.25E-01 1.362E+00 2.476E+00 7.59E+00

2. Average Release Rate Ci/sec 9.347E-03 3.354E-02 9.778E-02 1.714E-01 7.831e-02

3. Percent of ODCM Limit -

gamma  % 9.99E-05 2.84E-4 1.08E-03 2.78E-03 2.12E-03

4. Percent of ODCM Limit -

% 9.59E-05 2.96E-04 1.03E-03 7.14E-04 1.07E-03 beta B. Iodine Releases

1. Total Iodine-131 Ci 1.241E-05 4.113E-05 6.187E-04 8.008E-04 1.473E-03 3.32E+01

2. Average Release Rate Ci/sec 1.578E-06 5.231E-06 7.783E-05 1.007E-04 4.658E-05

3. Percent of ODCM Limit1  % 1.91E+00 1.86E+00 2.14E+00 1.46E+00 3.69E+00 C. Particulate (> 8-day half-life) Releases

1. Particulates with half-life >

8 days Ci <LLD <LLD <LLD <LLD <LLD 1.98E+01

2. Average Release Rate Ci/sec <LLD <LLD <LLD <LLD <LLD

3. Percent of ODCM Limit1  % 1.91E+00 1.86E+00 2.14E+00 1.46E+00 3.69E+00 D. Tritium Releases

1. Total Release Activity Ci 8.166E+0 2.713E+0 2.395E+01 2.363E+01 8.288E+01 8.07E+00

2. Average Release Rate 0 Ci/sec 1.039E+0 1 3.450E+0 3.013E+00 2.973E+00 2.621E+00

3. Percent of ODCM Limit11  % 0 1.91E+00 1.86E+000 2.14E+00 1.46E+00 3.69E+00 E. Gross Alpha Releases

1. Total Release Activity Ci <LLD <LLD <LLD <LLD <LLD 1.98E+01

2. Average Release Rate Ci/sec N/A N/A N/A N/A N/A

3. Percent of ODCM limit1  % N/A N/A N/A N/A N/A F. Carbon-14 Releases

1. Total Release Activity Ci 2.041E+0 1.991E+00 2.289E+00 2.222E+00 8.544E+00

2. Average Release Rate 0 Ci/sec 2.596E-01 2.533E-01 2.880E-01 2.795E-01 2.702E-01

3. Percent of ODCM limit1  % 1.91E+00 1.86E+00 2.14E+00 1.46E+00 3.69E+00 Note: ODCM LLD threshold values are included in Table 4.i of this report.

Note: The ODCM Limit is a dose-based limit combined for Iodines, Particulate, Tritium and C-14.

1 Combined Limit per 10CFR50 Appendix I for Organ Dose Due to Specified Non-Noble Gas Radionuclides.

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TABLE 1B-1 GASEOUS EFFLUENTS - MIXED MODE RELEASES - CONTINUOUS MODE UNIT 1 AND UNIT 2 Nuclides Released Continuous Mode A. Fission Gases Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Ar-41 Ci <LLD <LLD <LLD <LLD <LLD Kr-85 Ci <LLD <LLD <LLD <LLD <LLD Kr-87 Ci <LLD <LLD <LLD <LLD <LLD Kr-88 Ci <LLD <LLD <LLD <LLD <LLD Xe-131m Ci <LLD <LLD <LLD <LLD <LLD Xe-133 Ci <LLD <LLD <LLD <LLD <LLD Xe-133m Ci <LLD <LLD <LLD <LLD <LLD Xe-135 Ci <LLD <LLD <LLD <LLD <LLD Xe-138 Ci <LLD <LLD <LLD <LLD <LLD Total for Period Ci <LLD <LLD <LLD <LLD <LLD B. Iodines / Halogens Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Br-82 Ci <LLD <LLD <LLD 6.185E-05 6.185E-05 I-131 Ci <LLD <LLD <LLD <LLD <LLD I-132 Ci <LLD <LLD <LLD <LLD <LLD I-133 Ci <LLD <LLD <LLD <LLD <LLD I-134 Ci <LLD <LLD <LLD <LLD <LLD Total for Period Ci <LLD <LLD <LLD 6.185E-05 6.185E-05 C. Particulates Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Mn-54 Ci <LLD <LLD <LLD <LLD <LLD Co-57 Ci <LLD <LLD <LLD <LLD <LLD Co-58 Ci <LLD <LLD <LLD <LLD <LLD Fe-59 Ci <LLD <LLD <LLD <LLD <LLD Co-60 Ci <LLD <LLD <LLD <LLD <LLD Zn-65 Ci <LLD <LLD <LLD <LLD <LLD Sr-89 Ci <LLD <LLD <LLD <LLD <LLD Sr-90 Ci <LLD <LLD <LLD <LLD <LLD Mo-99 Ci <LLD <LLD <LLD <LLD <LLD Cs-134 Ci <LLD <LLD <LLD <LLD <LLD Cs-137 Ci <LLD <LLD <LLD <LLD <LLD Ba-140 Ci <LLD <LLD <LLD <LLD <LLD Total for Period Ci <LLD <LLD <LLD <LLD <LLD TABLE 1B-1 (Cont.)

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GASEOUS EFFLUENTS - MIXED MODE RELEASES - CONTINUOUS MODE UNIT 1 AND UNIT 2 Nuclides Released Continuous Mode C. Tritium Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Ci 7.174E+00 2.441E+01 1.501E+01 6.989E+00 5.358E+01 D. Gross Alpha Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Ci <LLD <LLD <LLD <LLD <LLD E. Carbon-14 Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Ci 2.041E+00 1.991E+00 2.289E+00 2.222E+00 8.544E+00 23 of 94

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TABLE 1B-2 GASEOUS EFFLUENTS - MIXED MODE RELEASES - BATCH MODE UNIT 1 AND UNIT 2 Nuclides Released Batch Mode A. Fission Gases Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Ar-41 Ci 7.129E-02 1.990E-01 7.724E-01 1.356E+00 2.398E+00 Kr-85 Ci <LLD <LLD <LLD <LLD <LLD Kr-85m Ci <LLD <LLD <LLD <LLD <LLD Kr-87 Ci <LLD <LLD <LLD <LLD <LLD Kr-88 Ci <LLD <LLD <LLD <LLD <LLD Xe-131m Ci <LLD <LLD <LLD <LLD <LLD Xe-133 Ci 2.196E-03 5.804E-02 4.754E-03 6.571E-03 7.156E-02 Xe-133m Ci <LLD <LLD <LLD <LLD <LLD Xe-135 Ci <LLD 6.663E-03 <LLD <LLD 6.663E-03 Xe-135m Ci <LLD <LLD <LLD <LLD <LLD Xe-138 Ci <LLD <LLD <LLD <LLD <LLD Total for Period Ci 7.349E-02 2.637E-01 7.772E-01 1.362E+00 2.476E+00 B. Iodines / Halogens Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Br-80 Ci <LLD 1.594E-05 5.288E-04 5.651E-04 1.110E-03 Br-82 Ci 1.241E-05 2.406E-05 8.259E-05 1.529E-04 2.719E-04 I-131 Ci <LLD 1.897E-07 1.723E-06 4.771E-06 6.684E-06 I-133 Ci <LLD 9.316E-07 5.235E-06 1.615E-05 2.231E-05 I-135 Ci <LLD 7.408E-09 <LLD <LLD <LLD Total for Period Ci 1.241E-05 4.113E-05 6.187E-04 7.389E-04 1.411E-03 C. Particulates Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Mn-54 Ci <LLD <LLD <LLD <LLD <LLD Co-57 Ci <LLD <LLD <LLD <LLD <LLD Co-58 Ci <LLD <LLD <LLD <LLD <LLD Fe-59 Ci <LLD <LLD <LLD <LLD <LLD Co-60 Ci <LLD <LLD <LLD <LLD <LLD Zn-65 Ci <LLD <LLD <LLD <LLD <LLD Sr-89 Ci <LLD <LLD <LLD <LLD <LLD Sr-90 Ci <LLD <LLD <LLD <LLD <LLD Mo-99 Ci <LLD <LLD <LLD <LLD <LLD Cs-134 Ci <LLD <LLD <LLD <LLD <LLD Cs-137 Ci <LLD <LLD <LLD <LLD <LLD 24 of 94

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TABLE 1B-2 (Cont.)

GASEOUS EFFLUENTS - MIXED MODE RELEASES - BATCH MODE UNIT 1 AND UNIT 2 Nuclides Released Batch Mode C. Particulates (Cont.) Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Ba-140 Ci <LLD <LLD <LLD <LLD <LLD La-140 Ci <LLD <LLD <LLD <LLD <LLD Total for Period Ci <LLD <LLD <LLD <LLD <LLD D. Tritium Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Ci 9.921E-01 2.721E+00 8.945E+00 1.664E+01 2.930E+01 E. Gross Alpha Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Ci <LLD <LLD <LLD <LLD <LLD F. Carbon-14 Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Ci <LLD <LLD <LLD <LLD <LLD 25 of 94

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TABLE 2A LIQUID EFFLUENTS- - SUMMATION OF ALL RELEASES UNIT 1 AND UNIT 2 Est.

Unit 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr Annual Total Error %

A. Fission and Activation Products

1. Total Release Ci 1.096E-02 5.347E-02 4.577E-03 2.873E-03 7.188E-02 2.64E+00

2. Average Diluted Concentration Ci/mL 1.049E-09 4.576E-09 5.467E-10 3.552E-10 1.863E-09

3. Percent of applicable limit  % * * * *

• B. Tritium

1. Total Release Ci 5.302E+02 1.10E+02 1.612E+02 1.02E+02 1.910E+03 5.85E+00

2. Average Diluted Concentration Ci/mL 5.077E-05 8.246E-05 1.925E-05 3.158E-05 4.951E-05

3. % of Limit (1E-2 Ci/ml)  % 5.077E-01 8.246E-01 1.925E-01 3.158E-01 4.951E-01 C. Dissolved Noble Gases D. E. F. G. H.

1. Total Release Ci <LLD <LLD <LLD <LLD <LLD 2.64E+00

2. Average Diluted Concentration Ci/mL N/A N/A N/A N/A N/A

3. % of Limit (2E-4 Ci/ml)  % N/A N/A N/A N/A N/A D. Gross Alpha

1. Total Release Ci <LLD <LLD <LLD <LLD <LLD 1.47E+01

2. Average Diluted Concentration µCi/ml N/A N/A N/A N/A N/A E. Volume of Waste Released Liters 8.547E+9 7.962E+09 6.403E+09 4.288E+09 2.720E+10 (prior to dilution)

F. Volume of Dilution Water Liters 1.897E+09 3.723E+09 1.968E+09 3.801E+09 1.139E+10 G. Average Stream Flow1 m3/s 2.72E+02 2.68E+02 5.37E+01 3.26E+01 1.51E+02 Note: ODCM LLD threshold values are included in Table 4.i of this report.

• This limit is equal to 10 times the concentration values in Appendix B, Table 2, Column 2 to 10CFR20.1001-20.2402, except for Dissolved Noble Gases. The limits for Dissolved Noble Gases are found the Braidwood Station ODCM, Table C-6 of ODCM Appendix C for Noble Gases.

1 Kankakee River Flows obtained from US Geological Survey website from daily average flow data.

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TABLE 2B-1 LIQUID EFFLUENTS - CONTINUOUS MODE UNIT 1 AND UNIT 2 Nuclides Released Continuous Mode A. Fission and Activation Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Products Mn-54 Ci <LLD <LLD <LLD <LLD <LLD Fe-55 Ci <LLD <LLD <LLD <LLD <LLD Fe-59 Ci <LLD <LLD <LLD <LLD <LLD Co-58 Ci <LLD <LLD <LLD <LLD <LLD Co-60 Ci <LLD <LLD <LLD <LLD <LLD Zn-65 Ci <LLD <LLD <LLD <LLD <LLD Cs-134 Ci <LLD <LLD <LLD <LLD <LLD Cs-137 Ci <LLD <LLD <LLD <LLD <LLD Ce-141 Ci <LLD <LLD <LLD <LLD <LLD Ce-144 Ci <LLD <LLD <LLD <LLD <LLD Total for Period Ci <LLD <LLD <LLD <LLD <LLD B. Tritium Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Ci 1.696E+01 6.876E+01 7.181E+00 6.767E-01 9.358E+01 C. Dissolved and Entrained Gases Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Kr-87 Ci <LLD <LLD <LLD <LLD <LLD Kr-88 Ci <LLD <LLD <LLD <LLD <LLD Xe-133 Ci <LLD <LLD <LLD <LLD <LLD Xe-133m Ci <LLD <LLD <LLD <LLD <LLD Xe-135 Ci <LLD <LLD <LLD <LLD <LLD Xe-138 Ci <LLD <LLD <LLD <LLD <LLD Total for Period Ci <LLD <LLD <LLD <LLD <LLD D. Gross Alpha Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Ci <LLD <LLD <LLD <LLD <LLD 27 of 94

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TABLE 2B-2 LIQUID EFFLUENTS - BATCH MODE UNIT 1 AND UNIT 2 Nuclides Released Batch Mode A. Fission and Activation Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Products Cr-51 Ci 1.767E-04 6.205E-03 <LLD <LLD 6.382E-03 Mn-54 Ci 1.954E-04 2.105E-04 <LLD <LLD 4.059E-04 Fe-55 Ci 3.607E-03 2.987E-03 7.292E-04 <LLD 7.323E-03 Fe-59 Ci <LLD 1.378E-03 <LLD <LLD 1.378E-03 Co-57 Ci <LLD 1.104E-05 <LLD <LLD 1.104E-05 Co-58 Ci 1.349E-03 1.728E-02 1.392E-03 4.840E-04 2.051E-02 Co-60 Ci 5.256E-03 6.904E-03 6.384E-04 5.281E-04 1.333E-02 Zr-95 Ci <LLD 2.537E-04 <LLD <LLD 2.537E-04 Nb-95 Ci 1.839E-04 5.140E-04 <LLD <LLD 6.979E-04 Nb-97 Ci 1.689E-05 <LLD <LLD <LLD 1.689E-05 Mo-99 Ci <LLD <LLD <LLD <LLD <LLD Tc-99m Ci <LLD <LLD <LLD <LLD <LLD Ag-110m Ci 1.010E-04 1.587E-04 <LLD <LLD 2.59E-04 Sn-113 Ci <LLD <LLD <LLD <LLD <LLD Sb-122 Ci <LLD <LLD <LLD <LLD <LLD Sb-124 Ci <LLD 3.537E-04 <LLD <LLD 3.537E-04 Sb-125 Ci 7.334E-05 1.721E-02 1.817E-03 1.861E-03 2.096E-02 Sb-126 Ci <LLD <LLD <LLD <LLD <LLD Te-123m Ci <LLD <LLD <LLD <LLD <LLD Te-125m Ci <LLD <LLD <LLD <LLD <LLD Te-129m Ci <LLD <LLD <LLD <LLD <LLD Cs-134 Ci <LLD <LLD <LLD <LLD <LLD Cs-136 Ci <LLD <LLD <LLD <LLD <LLD Cs-137 Ci <LLD <LLD <LLD <LLD <LLD Total for Period Ci 1.096E-02 5.347E-02 4.577E-03 2.873E-03 7.188E-02 B. Tritium Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Ci 5.132E+02 8.948E+02 1.540E+02 2.548E+02 1.817E+03 C. Dissolved and Entrained Gases Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Kr-87 Ci <LLD <LLD <LLD <LLD <LLD Kr-88 Ci <LLD <LLD <LLD <LLD <LLD Xe-133 Ci <LLD <LLD <LLD <LLD <LLD Xe-133m Ci <LLD <LLD <LLD <LLD <LLD Xe-135 Ci <LLD <LLD <LLD <LLD <LLD 28 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Xe-138 Ci <LLD <LLD <LLD <LLD <LLD Total for Period Ci <LLD <LLD <LLD <LLD <LLD TABLE 2B-2 (Cont.)

LIQUID EFFLUENTS - BATCH MODE UNIT 1 AND UNIT 2 Nuclides Released Batch Mode D. Gross Alpha Unit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Ci <LLD <LLD <LLD <LLD <LLD 29 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

APPENDIX B: SOLID WASTE AND IRRADIATED FUEL SHIPMENTS 30 of 94

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

1. Low-Level Waste Resins, Filters, And Evaporator Bottoms Waste Volume Curies Class ft³ m³ Shipped A 3.50E+03 9.92E+01 4.25E+01 B 1.84E+02 5.21E+00 2.46E+02 C 0.00E+00 0.00E+00 0.00E+00 All 3.69E+03 1.04E+02 2.89E+02 Major Nuclides for the Above Table:

H-3, C-14, Mn-54, Fe-55, Co-58, Co-60, Ni-59, Ni-63, Zn-65, Sr-90, Tc-99, Sb-125, I-129, Cs-137, Pu-238, Pu-239, Pu-241, Am-241, Cm-243, Cm-244 Dry Active Waste (DAW)

Waste Volume Curies Class ft³ m³ Shipped A 3.47E+03 9.81E+01 1.65E+00 B 0.00E+00 0.00E+00 0.00E+00 C 0.00E+00 0.00E+00 0.00E+00 All 3.47E+03 9.81E+01 1.65E+00 Major Nuclides for the Above Table:

H-3, C-14, Cr-51, Mn-54, Fe-55, Co-58, Co-60, Ni-59, Ni-63, Sr-90, Zr-95, Nb-95, Tc-99, Sb-125, I-129, Cs-137, Pu-238, Pu-241, Am-241, Cm-242, Cm-243, Cm-244 Irradiated Components Waste Volume Curies Class ft³ m³ Shipped A 0.00E+00 0.00E+00 0.00E+00 B 0.00E+00 0.00E+00 0.00E+00 C 0.00E+00 0.00E+00 0.00E+00 All 0.00E+00 0.00E+00 0.00E+00 Major Nuclides for the Above Table:

None 31 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

1. Low-Level Waste (continued)

Other Waste Waste Volume Curies Class ft³ m³ Shipped A 7.14E+02 2.02E+01 3.83E-02 B 0.00E+00 0.00E+00 0.00E+00 C 0.00E+00 0.00E+00 0.00E+00 All 7.14E+02 2.02E+01 3.83E-02 Major Nuclides for the Above Table:

C-14, Cr-51, Mn-54, Fe-55, Co-58, Co-60, Ni-59, Ni-63, Sr-90, Zr-95, Nb-95, Tc-99, Sb-125, I-129, Cs-137, Pu-238, Pu-241, Am-241, Cm-242, Cm-243, Cm-244 Sum of All Low-Level Waste Shipped from Site Waste Volume Curies Class ft³ m³ Shipped A 1.43E+03 2.18E+02 4.42E+01 B 1.84E+02 5.21E+00 2.46E+02 C 0.00E+00 0.00E+00 0.00E+00 All 7.87E+03 2.23E+02 2.90E+02 Major Nuclides for the Above Table:

H-3, C-14, Cr-51, Mn-54, Fe-55, Co-58, Co-60, Ni-59, Ni-63, Zn-65, Sr-90, Zr-95, Nb-95, Tc-99, Sb-125, I-129, Cs-137, Pu-238, Pu-239, Pu-241, Am-241, Cm-242, Cm-243, Cm-244

2. Estimate of Major Nuclide Composition (By Waste Type and Class)

a. Category A - Spent Resins, Filter Sludges, Evaporator Bottoms, etc.

Waste Class Percent Waste Class Percent Isotope A Curies Abundance B Curies Abundance H-3 4.32E+00 10.17% 3.15E+00 1.28%

Be-7 NA 0.00% 3.69E-01 0.15%

C-14 2.53E-02 0.06% 7.18E-02 0.03%

Cr-51 5.63E-01 1.32% 6.76E-05 0.00%

Mn-54 4.73E-01 1.11% 1.64E+01 6.67%

Fe-55 4.73E+00 11.11% 9.20E+01 37.36%

Co-57 5.65E-02 0.13% 7.44E-01 0.30%

Co-58 2.94E+00 6.91% 1.26E+01 5.11%

Co-60 6.48E+00 15.23% 8.02E+01 32.56%

Ni-59 7.39E-01 1.74% 9.73E-01 0.39%

Ni-63 1.78E+01 41.83% 3.36E+01 13.63%

Zn-65 5.63E-02 0.13% 2.90E+00 1.18%

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BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Isotope Waste Class Percent Waste Class Percent (continued) A Curies Abundance B Curies Abundance Sr-89 NA 0.00% 3.30E-03 0.00%

Sr-90 5.09E-03 0.01% 7.12E-03 0.00%

Zr-95 1.16E+00 2.72% 2.04E-05 0.00%

Nb-95 1.12E+00 2.64% 1.71E-03 0.00%

Tc-99 NA 0.00% 1.87E-02 0.01%

Ag-110m 6.99E-02 0.16% 1.40E-02 0.01%

Sn-113 5.18E-02 0.12% 4.00E-02 0.02%

Sb-124 2.97E-02 0.07% 1.14E-03 0.00%

Sb-125 1.48E+00 3.48% 2.04E+00 0.83%

Cs-134 4.16E-02 0.10% 1.76E-02 0.01%

Cs-137 3.46E-01 0.81% 8.97E-01 0.36%

Ce-144 6.18E-02 0.15% 2.61E-01 0.11%

Pu-238 6.04E-06 0.00% 3.59E-05 0.00%

Pu-239 3.25E-06 0.00% 7.06E-06 0.00%

Pu-241 7.25E-04 0.00% 1.95E-02 0.01%

Am-241 1.52E-05 0.00% 1.61E-05 0.00%

Cm-242 6.80E-06 0.00% 1.61E-06 0.00%

Cm-244 2.96E-05 0.00% 3.65E-05 0.00%

b. Category B - Dry Compressible Waste, Contaminated Equip, etc.

Waste Class Percent Isotope A Curies Abundance H-3 1.93E-02 1.17%

C-14 1.86E-02 1.13%

Cr-51 1.19E-02 0.73%

Mn-54 9.06E-03 0.55%

Fe-55 2.38E-01 14.47%

Fe-59 2.38E-01 0.14%

Co-57 1.20E-03 0.07%

Co-58 6.83E-02 4.15%

Co-60 2.55E-01 15.48%

Ni-59 9.13E-03 0.55%

Ni-63 8.39E-01 50.94%

Zn-65 2.35E-03 0.14%

Sr-89 2.09E-37 0.00%

Sr-90 8.21E-04 0.05%

Zr-95 8.19E-03 0.50%

Nb-95 1.12E-02 0.68%

Tc-99 1.97E-03 0.12%

Ag-110m 1.51E-03 0.09%

Sn-113 1.04E-03 0.06%

Sn-117m 5.78E-158 0.00%

Sb-124 5.70E-39 0.00%

Te-123m 4.66E-22 0.00%

Sb-125 9.47E-03 0.58%

I-129 6.27E-06 0.00%

Cs-134 5.57E-04 0.03%

Cs-137 1.36E-01 8.28%

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BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Ce-144 4.92E-04 0.03%

Pu-238 1.77E-05 0.00%

Pu-239 1.04E-06 0.00%

Pu-241 6.19E-04 0.04%

Am-241 2.58E-05 0.00%

Cm-242 4.53E-06 0.00%

Cm-243 3.00E-05 0.00%

Cm-244 3.40E-05 0.00%

c. Category C - Irradiated Components, Control Rods, etc.

None

d. Category D - Other (Oil, Reverse Osmosis Reject Water, Soil, Lagoon Sediment)

Waste Class Percent Isotope A Curies Abundance H-3 1.33E-2 34.61%

Cr-51 9.16E-04 2.39%

Mn-54 2.16E-04 0.56%

Fe-55 5.67E-03 14.78%

Fe-59 1.19E-04 0.31%

Co-57 2.66E-05 0.07%

Co-58 3.07E-03 8.02%

Co-60 5.49E-03 14.31%

Ni-59 8.27E-05 0.22%

Ni-63 9.16E-03 21.29%

Zn-65 5.75E-05 0.15%

Sr-90 2.21E-05 0.06%

Zr-95 4.06E-04 1.06%

Nb-95 4.10E-04 1.07%

Tc-99 2.73E-05 0.07%

Ag-110m 3.51E-05 0.09%

Sn-113 3.35E-05 0.09%

Sb-125 2.08E-04 0.54%

Cs-137 9.48E-05 0.25%

Ce-144 1.50E-05 0.04%

Pu-238 5.02E-07 0.00%

Pu-241 9.10E-06 0.02%

Am-241 6.59E-07 0.00%

Cm-242 1.22E-07 0.00%

Cm-243 1.05E-06 0.00%

Cm-244 1.05E-06 0.00%

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BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

3. Solid Waste Disposition Number of Mode of Transportation Destination Shipments 4 Hittman Transportation Energy Solutions Services - Gallaher Rd 628 Gallaher Rd.

7 Hittman Transportation Energy Solutions-Bear Creek Facility 1560 Bear Creek Road 6 Hittman Transportation EnergySolutions LLC.

1 Hittman Transportation Erwin ResinSoulutions, LLC 1 Hittman Transportation Waste Control Specialists - TSDF B. Irradiated Fuel Shipments None C. Irradiated Fuel Shipments (disposition)

No irradiated fuel shipments were dispositioned at Braidwood during January through December 2020.

D. Changes to the Process Control Program (PCP)

There were no Process Control Changes in 2020.

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BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

APPENDIX C: WIND DIRECTION AND STABILITY CLASSES 36 of 94

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WIND STABILITY CLASSES Atmospheric Stability Classes, Table C-4 from Braidwood ODCM.

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BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: January - March 2020 Stability Class - Extremely Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 2 5 1 0 0 8 NNE 0 0 0 0 0 0 0 NE 0 1 0 0 0 0 1 ENE 0 2 0 0 0 0 2 E 0 1 0 0 0 0 1 ESE 0 0 2 0 0 0 2 SE 0 0 0 0 0 0 0 SSE 0 0 1 0 0 0 1 S 0 0 6 4 0 0 10 SSW 0 0 0 4 10 0 14 SW 0 1 12 5 0 0 18 WSW 0 3 9 1 0 0 13 W 1 3 4 8 2 0 18 WNW 0 9 10 12 3 0 34 NW 0 10 17 0 0 0 27 NNW 0 5 21 2 0 0 28 Variable 0 0 0 0 0 0 0 Total 1 37 87 37 15 0 177 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 3 38 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: January - March 2020 Stability Class - Moderately Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 1 1 0 0 0 2 NNE 0 0 0 0 0 0 0 NE 0 4 2 0 0 0 6 ENE 0 4 0 0 0 0 4 E 0 3 0 0 0 0 3 ESE 0 2 2 0 0 0 4 SE 0 0 0 0 0 0 0 SSE 0 1 1 0 0 0 2 S 0 1 4 2 0 0 7 SSW 0 0 3 5 1 0 9 SW 0 0 2 4 0 0 6 WSW 0 1 2 1 0 0 4 W 0 2 8 3 5 0 18 WNW 0 11 3 6 7 0 27 NW 0 10 9 0 0 0 19 NNW 0 3 12 1 0 0 16 Variable 0 0 0 0 0 0 0 Total 0 43 49 22 13 0 127 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 3 39 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: January - March 2020 Stability Class - Slightly Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 2 1 0 0 0 3 NNE 1 0 6 3 0 0 10 NE 0 2 5 2 0 0 9 ENE 3 11 0 0 0 0 14 E 1 1 2 0 0 0 4 ESE 0 0 6 0 0 0 6 SE 0 4 1 0 0 0 5 SSE 0 5 2 0 0 0 7 S 0 3 5 5 0 0 13 SSW 0 1 3 3 0 0 7 SW 0 2 5 3 0 0 10 WSW 0 8 7 2 0 0 17 W 0 11 5 2 1 0 19 WNW 1 11 12 3 0 0 27 NW 1 8 4 0 0 0 13 NNW 0 7 5 3 0 0 15 Variable 0 0 0 0 0 0 0 Total 7 76 69 26 1 0 179 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 3 40 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: January - March 2020 Stability Class - Neutral - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 7 14 13 1 0 0 35 NNE 6 31 53 26 0 0 116 NE 7 26 44 4 0 0 81 ENE 14 50 5 0 0 0 69 E 15 38 4 0 0 0 57 ESE 1 32 20 2 0 0 55 SE 4 26 29 6 0 0 65 SSE 2 37 51 9 0 0 99 S 0 11 51 49 11 0 122 SSW 1 4 20 34 10 0 69 SW 0 19 33 14 2 0 68 WSW 1 36 18 6 4 2 67 W 9 35 40 13 3 1 101 WNW 13 45 39 22 1 0 120 NW 14 44 10 4 0 0 72 NNW 6 47 21 10 0 0 84 Variable 0 0 0 0 0 0 0 Total 100 495 451 200 31 3 1280 Hours of calm in this stability class: 4 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 3 41 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: January - March 2020 Stability Class - Slightly Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 1 2 0 0 0 0 3 NNE 2 3 0 0 0 0 5 NE 4 1 0 0 0 0 5 ENE 18 12 0 0 0 0 30 E 21 12 0 0 0 0 33 ESE 6 7 0 0 0 0 13 SE 3 5 2 0 0 0 10 SSE 4 8 6 1 0 0 19 S 1 4 5 0 1 0 11 SSW 1 4 6 3 0 0 14 SW 0 15 14 2 0 0 31 WSW 5 20 3 0 0 0 28 W 11 16 5 0 0 0 32 WNW 15 34 11 1 0 0 61 NW 7 7 1 0 0 0 15 NNW 4 1 0 0 0 0 5 Variable 0 0 0 0 0 0 0 Total 103 151 53 7 1 0 315 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 3 42 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: January - March 2020 Stability Class - Moderately Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 1 0 0 0 0 0 1 NNE 1 0 0 0 0 0 1 NE 3 0 0 0 0 0 3 ENE 5 1 0 0 0 0 6 E 5 0 0 0 0 0 5 ESE 2 0 0 0 0 0 2 SE 1 1 0 0 0 0 2 SSE 0 0 0 0 0 0 0 S 2 0 0 0 0 0 2 SSW 0 3 5 0 0 0 8 SW 4 4 2 0 0 0 10 WSW 1 6 1 0 0 0 8 W 6 8 0 0 0 0 14 WNW 8 0 0 0 0 0 8 NW 3 0 0 0 0 0 3 NNW 3 0 0 0 0 0 3 Variable 0 0 0 0 0 0 0 Total 45 23 8 0 0 0 76 Hours of calm in this stability class: 1 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 3 43 of 94

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Braidwood Generating Station Period of Record: January - March 2020 Stability Class - Extremely Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 0 0 0 0 0 0 NNE 1 0 0 0 0 0 1 NE 0 1 0 0 0 0 1 ENE 1 0 0 0 0 0 1 E 4 1 0 0 0 0 5 ESE 0 0 0 0 0 0 0 SE 0 0 0 0 0 0 0 SSE 0 0 0 0 0 0 0 S 1 0 0 0 0 0 1 SSW 0 1 0 0 0 0 1 SW 2 0 0 0 0 0 2 WSW 1 0 0 0 0 0 1 W 3 1 0 0 0 0 4 WNW 3 0 0 0 0 0 3 NW 2 0 0 0 0 0 2 NNW 0 0 0 0 0 0 0 Variable 0 0 0 0 0 0 0 Total 18 4 0 0 0 0 22 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 3 44 of 94

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Braidwood Generating Station Period of Record: January - March 2020 Stability Class - Extremely Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 1 6 0 1 0 8 NNE 0 0 0 0 0 0 0 NE 0 1 0 0 0 0 1 ENE 0 1 1 0 0 0 2 E 0 0 1 0 0 0 1 ESE 0 0 0 2 0 0 2 SE 0 0 0 0 0 0 0 SSE 0 0 0 1 0 0 1 S 0 0 1 6 3 0 10 SSW 0 0 0 0 4 10 14 SW 0 2 7 9 1 0 19 WSW 0 3 6 3 1 0 13 W 1 2 1 7 5 1 17 WNW 0 3 9 7 10 4 33 NW 0 2 7 16 1 0 26 NNW 0 3 14 11 2 0 30 Variable 0 0 0 0 0 0 0 Total 1 18 53 62 28 15 177 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 3 45 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: January - March 2020 Stability Class - Moderately Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 0 0 1 0 0 1 NNE 0 0 0 0 0 0 0 NE 0 1 3 2 0 0 6 ENE 0 2 1 0 0 0 3 E 0 0 4 0 0 0 4 ESE 0 1 1 1 1 0 4 SE 0 0 0 0 0 0 0 SSE 0 0 2 0 0 0 2 S 0 0 3 2 3 0 8 SSW 0 0 1 2 3 1 7 SW 0 0 3 1 3 0 7 WSW 0 0 2 1 1 0 4 W 0 0 5 6 1 5 17 WNW 0 7 4 3 5 7 26 NW 0 7 5 10 1 0 23 NNW 0 3 3 7 2 0 15 Variable 0 0 0 0 0 0 0 Total 0 21 37 36 20 13 127 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 3 46 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: January - March 2020 Stability Class - Slightly Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 0 3 0 0 0 3 NNE 0 0 1 4 5 0 10 NE 0 0 3 4 1 0 8 ENE 3 4 6 0 0 0 13 E 0 2 1 2 0 0 5 ESE 0 1 0 6 0 0 7 SE 0 1 3 1 0 0 5 SSE 0 3 3 1 0 0 7 S 0 2 4 2 4 1 13 SSW 0 0 2 2 3 0 7 SW 0 2 3 3 3 0 11 WSW 0 7 8 3 2 0 20 W 0 4 5 2 2 1 14 WNW 1 6 4 9 5 0 25 NW 1 8 3 1 1 0 14 NNW 0 4 5 5 2 1 17 Variable 0 0 0 0 0 0 0 Total 5 44 54 45 28 3 179 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 3 47 of 94

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Braidwood Generating Station Period of Record: January - March 2020 Stability Class - Neutral - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 2 7 16 10 2 0 37 NNE 0 7 30 42 27 5 111 NE 2 5 39 33 5 0 84 ENE 3 24 26 3 0 0 56 E 1 16 38 10 1 0 66 ESE 1 6 9 25 9 2 52 SE 2 7 22 22 9 1 63 SSE 0 14 38 35 11 2 100 S 0 3 18 43 40 23 127 SSW 1 2 4 18 34 18 77 SW 1 9 22 27 12 2 73 WSW 2 10 33 8 6 6 65 W 3 12 27 38 5 9 94 WNW 2 17 28 29 20 10 106 NW 3 19 34 22 4 3 85 NNW 3 12 42 16 10 4 87 Variable 0 0 0 0 0 0 0 Total 26 170 426 381 195 85 1283 Hours of calm in this stability class: 1 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 3 48 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: January - March 2020 Stability Class - Slightly Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 1 0 1 1 0 0 3 NNE 0 0 3 0 0 0 3 NE 1 1 3 0 0 0 5 ENE 2 4 11 0 0 0 17 E 2 2 22 1 0 0 27 ESE 0 5 15 3 0 0 23 SE 1 3 4 2 0 0 10 SSE 0 6 5 9 2 0 22 S 1 2 8 3 1 1 16 SSW 0 1 1 10 5 2 19 SW 0 2 10 13 1 0 26 WSW 0 6 14 2 0 0 22 W 1 5 15 9 1 0 31 WNW 0 3 26 14 6 0 49 NW 1 6 20 4 2 0 33 NNW 1 1 6 1 0 0 9 Variable 0 0 0 0 0 0 0 Total 11 47 164 72 18 3 315 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 3 49 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: January - March 2020 Stability Class - Moderately Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 1 0 0 0 0 1 NNE 0 0 1 0 0 0 1 NE 0 0 0 1 0 0 1 ENE 1 4 1 0 0 0 6 E 0 0 3 0 0 0 3 ESE 0 0 3 1 0 0 4 SE 0 1 1 0 0 0 2 SSE 1 0 0 0 0 0 1 S 0 2 0 0 0 0 2 SSW 0 2 0 0 0 0 2 SW 0 2 4 7 1 0 14 WSW 0 2 5 3 0 0 10 W 0 1 5 6 0 0 12 WNW 0 1 4 0 0 0 5 NW 0 4 4 0 0 0 8 NNW 0 2 3 0 0 0 5 Variable 0 0 0 0 0 0 0 Total 2 22 34 18 1 0 77 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 3 50 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: January - March 2020 Stability Class - Extremely Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 1 0 0 0 0 1 NNE 0 0 0 0 0 0 0 NE 0 0 1 1 0 0 2 ENE 0 0 0 0 0 0 0 E 0 1 0 0 0 0 1 ESE 0 0 1 0 0 0 1 SE 0 1 0 0 0 0 1 SSE 0 1 0 0 0 0 1 S 0 1 0 0 0 0 1 SSW 0 2 0 0 0 0 2 SW 1 0 0 0 0 0 1 WSW 0 0 0 0 0 0 0 W 0 1 0 0 0 0 1 WNW 0 1 1 1 0 0 3 NW 0 2 1 0 0 0 3 NNW 0 1 3 0 0 0 4 Variable 0 0 0 0 0 0 0 Total 1 12 7 2 0 0 22 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 3 51 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: April - June 2020 Stability Class - Extremely Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 0 5 0 0 0 5 NNE 0 0 2 3 0 0 5 NE 0 3 17 0 0 0 20 ENE 0 4 5 0 0 0 9 E 0 17 5 0 0 0 22 ESE 0 2 1 0 0 0 3 SE 0 9 6 1 0 0 16 SSE 0 1 2 0 0 0 3 S 0 0 4 0 0 0 4 SSW 0 0 3 4 2 0 9 SW 0 2 3 3 2 0 10 WSW 0 1 5 1 1 0 8 W 0 1 14 10 0 0 25 WNW 0 3 13 9 4 0 29 NW 0 2 13 4 0 0 19 NNW 0 2 11 1 0 0 14 Variable 0 0 0 0 0 0 0 Total 0 47 109 36 9 0 201 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 52 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: April - June 2020 Stability Class - Moderately Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 3 4 0 0 0 7 NNE 0 1 3 1 0 0 5 NE 0 2 2 0 0 0 4 ENE 1 3 3 0 0 0 7 E 0 5 3 0 0 0 8 ESE 0 5 0 0 0 0 5 SE 0 8 2 0 0 0 10 SSE 0 5 7 3 0 0 15 S 0 1 2 1 0 0 4 SSW 0 3 1 0 1 0 5 SW 0 1 4 5 2 0 12 WSW 0 4 6 2 0 0 12 W 0 2 8 5 1 0 16 WNW 0 5 3 4 1 0 13 NW 0 5 3 0 0 0 8 NNW 0 3 3 0 0 0 6 Variable 0 0 0 0 0 0 0 Total 1 56 54 21 5 0 137 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 53 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: April - June 2020 Stability Class - Slightly Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 2 2 0 0 0 4 NNE 0 2 2 1 0 0 5 NE 0 6 7 0 0 0 13 ENE 0 4 4 0 0 0 8 E 0 7 1 0 0 0 8 ESE 0 9 0 0 0 0 9 SE 1 16 5 0 0 0 22 SSE 1 11 4 0 0 0 16 S 0 6 3 1 0 0 10 SSW 0 3 10 4 0 0 17 SW 0 0 3 3 1 0 7 WSW 0 4 7 1 0 0 12 W 0 6 3 1 1 0 11 WNW 0 3 10 2 0 0 15 NW 0 5 8 0 0 0 13 NNW 0 4 6 1 0 0 11 Variable 0 0 0 0 0 0 0 Total 2 88 75 14 2 0 181 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 54 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: April - June 2020 Stability Class - Neutral - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 5 12 11 4 0 0 32 NNE 1 20 36 6 0 0 63 NE 2 46 42 0 0 0 90 ENE 3 53 18 0 0 0 74 E 10 39 2 0 0 0 51 ESE 5 17 2 0 0 0 24 SE 4 24 6 3 0 0 37 SSE 2 39 36 5 0 0 82 S 0 13 27 12 0 0 52 SSW 2 6 26 18 1 0 53 SW 0 17 29 18 0 0 64 WSW 2 19 19 8 1 0 49 W 5 20 14 5 0 0 44 WNW 1 20 29 9 0 0 59 NW 3 15 9 9 0 0 36 NNW 6 15 20 7 0 0 48 Variable 0 0 0 0 0 0 0 Total 51 375 326 104 2 0 858 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 55 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: April - June 2020 Stability Class - Slightly Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 4 14 0 0 0 0 18 NNE 3 8 1 0 0 0 12 NE 7 3 0 0 0 0 10 ENE 28 26 1 0 0 0 55 E 37 13 0 0 0 0 50 ESE 12 34 0 0 0 0 46 SE 3 32 1 0 0 0 36 SSE 4 36 8 0 0 0 48 S 5 19 13 5 0 0 42 SSW 2 9 18 6 0 0 35 SW 3 17 16 3 0 0 39 WSW 5 39 5 0 0 0 49 W 10 44 7 1 0 0 62 WNW 16 24 16 3 0 0 59 NW 15 7 1 0 0 0 23 NNW 5 4 2 0 0 0 11 Variable 0 0 0 0 0 0 0 Total 159 329 89 18 0 0 595 Hours of calm in this stability class: 1 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 56 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: April - June 2020 Stability Class - Moderately Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 2 0 1 0 0 0 3 NNE 0 1 0 0 0 0 1 NE 4 0 0 0 0 0 4 ENE 7 0 0 0 0 0 7 E 32 2 0 0 0 0 34 ESE 17 7 0 0 0 0 24 SE 7 2 0 0 0 0 9 SSE 5 4 0 0 0 0 9 S 1 1 0 0 0 0 2 SSW 0 0 0 0 0 0 0 SW 2 4 0 0 0 0 6 WSW 3 12 0 0 0 0 15 W 19 10 0 0 0 0 29 WNW 6 1 0 0 0 0 7 NW 4 0 1 0 0 0 5 NNW 2 0 0 0 0 0 2 Variable 0 0 0 0 0 0 0 Total 111 44 2 0 0 0 157 Hours of calm in this stability class: 2 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 57 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: April - June 2020 Stability Class - Extremely Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 0 0 0 0 0 0 NNE 1 0 0 0 0 0 1 NE 2 0 0 0 0 0 2 ENE 3 0 0 0 0 0 3 E 14 1 0 0 0 0 15 ESE 3 1 0 0 0 0 4 SE 2 0 0 0 0 0 2 SSE 0 0 0 0 0 0 0 S 0 0 0 0 0 0 0 SSW 1 0 0 0 0 0 1 SW 0 0 0 0 0 0 0 WSW 2 1 0 0 0 0 3 W 3 0 0 0 0 0 3 WNW 10 0 0 0 0 0 10 NW 2 0 0 0 0 0 2 NNW 2 0 0 0 0 0 2 Variable 0 0 0 0 0 0 0 Total 45 3 0 0 0 0 48 Hours of calm in this stability class: 4 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 58 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: April - June 2020 Stability Class - Extremely Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 0 2 3 0 0 5 NNE 0 0 0 3 2 0 5 NE 0 1 14 5 0 0 20 ENE 0 0 5 2 0 0 7 E 0 1 17 6 0 0 24 ESE 0 1 2 2 0 0 5 SE 0 4 5 4 1 0 14 SSE 0 0 3 1 0 0 4 S 0 0 2 1 0 0 3 SSW 0 0 0 6 2 2 10 SW 0 0 2 4 1 2 9 WSW 0 0 5 2 0 1 8 W 0 0 12 6 7 0 25 WNW 0 0 9 10 4 8 31 NW 0 0 5 6 6 1 18 NNW 0 0 8 4 1 0 13 Variable 0 0 0 0 0 0 0 Total 0 7 91 65 24 14 201 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 59 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: April - June 2020 Stability Class - Moderately Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 2 3 3 0 0 8 NNE 0 0 1 2 0 0 3 NE 0 1 2 1 0 0 4 ENE 0 1 2 1 0 0 4 E 0 2 5 5 0 0 12 ESE 0 3 0 0 0 0 3 SE 0 4 7 2 0 0 13 SSE 0 3 6 2 2 0 13 S 0 1 3 2 0 0 6 SSW 0 0 2 0 1 1 4 SW 0 1 4 2 3 2 12 WSW 0 0 6 4 1 0 11 W 0 1 7 3 4 1 16 WNW 0 0 5 2 1 4 12 NW 0 1 6 4 0 0 11 NNW 0 3 2 0 0 0 5 Variable 0 0 0 0 0 0 0 Total 0 23 61 33 12 8 137 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 60 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: April - June 2020 Stability Class - Slightly Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 1 2 1 0 0 4 NNE 0 2 2 0 1 0 5 NE 0 1 4 4 0 0 9 ENE 0 2 5 2 0 0 9 E 0 3 4 1 0 0 8 ESE 0 6 4 0 0 0 10 SE 0 11 12 2 0 0 25 SSE 0 4 6 2 0 0 12 S 0 8 4 1 1 0 14 SSW 0 1 6 6 1 1 15 SW 0 0 0 5 2 0 7 WSW 0 2 7 2 0 0 11 W 0 1 6 1 1 1 10 WNW 0 3 2 9 2 1 17 NW 0 4 4 5 1 0 14 NNW 0 2 6 1 1 0 10 Variable 0 0 0 0 0 0 0 Total 0 51 74 42 10 3 180 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 1 Hours of missing stability measurements in all stability classes: 0 61 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: April - June 2020 Stability Class - Neutral - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 1 10 13 7 4 1 36 NNE 1 6 11 17 9 0 44 NE 1 12 40 41 0 0 94 ENE 0 7 31 6 0 0 44 E 6 11 34 4 0 0 55 ESE 0 6 9 9 0 0 24 SE 2 7 18 6 2 2 37 SSE 0 10 30 30 4 4 78 S 3 3 15 21 11 1 54 SSW 1 2 15 26 17 8 69 SW 0 8 21 19 10 2 60 WSW 2 8 16 9 5 2 42 W 3 8 16 11 5 1 44 WNW 3 4 16 23 5 5 56 NW 1 6 10 16 2 8 43 NNW 1 10 5 17 8 2 43 Variable 0 0 0 0 0 0 0 Total 25 118 300 262 82 36 823 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 35 Hours of missing stability measurements in all stability classes: 0 62 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: April - June 2020 Stability Class - Slightly Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 1 2 13 2 0 0 18 NNE 0 4 3 1 0 0 8 NE 0 3 14 0 0 0 17 ENE 0 13 25 2 0 0 40 E 0 10 43 3 0 0 56 ESE 0 8 17 17 0 0 42 SE 0 5 18 8 0 0 31 SSE 0 1 30 14 0 0 45 S 0 4 26 11 4 0 45 SSW 1 5 14 17 13 0 50 SW 2 9 19 11 3 0 44 WSW 0 6 14 15 0 0 35 W 1 7 34 24 1 0 67 WNW 0 5 22 16 5 1 49 NW 0 4 21 10 2 0 37 NNW 1 1 6 2 0 0 10 Variable 0 0 0 0 0 0 0 Total 6 87 319 153 28 1 594 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 2 Hours of missing stability measurements in all stability classes: 0 Braidwood Generating Station 63 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Period of Record: April - June 2020 Stability Class - Moderately Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 1 2 0 0 0 3 NNE 0 3 1 0 0 0 4 NE 0 1 2 0 0 0 3 ENE 1 3 1 0 0 0 5 E 1 2 8 4 0 0 15 ESE 0 2 18 3 0 0 23 SE 0 4 11 5 0 0 20 SSE 1 1 4 0 0 0 6 S 0 3 5 2 0 0 10 SSW 1 3 0 0 0 0 4 SW 0 1 5 0 0 0 6 WSW 1 2 2 2 0 0 7 W 1 1 10 6 0 0 18 WNW 1 5 10 6 0 0 22 NW 0 4 5 0 0 0 9 NNW 0 1 3 0 0 0 4 Variable 0 0 0 0 0 0 0 Total 7 37 87 28 0 0 159 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 64 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: April - June 2020 Stability Class - Extremely Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 1 1 0 0 0 2 NNE 1 0 1 0 0 0 2 NE 0 0 0 0 0 0 0 ENE 1 2 0 0 0 0 3 E 1 0 1 0 0 0 2 ESE 1 1 4 3 0 0 9 SE 0 1 1 0 0 0 2 SSE 0 3 1 0 0 0 4 S 1 0 0 0 0 0 1 SSW 2 4 0 0 0 0 6 SW 2 2 1 0 0 0 5 WSW 1 1 1 0 0 0 3 W 0 1 3 1 0 0 5 WNW 0 0 0 0 0 0 0 NW 0 5 0 0 0 0 5 NNW 0 1 1 0 0 0 2 Variable 0 0 0 0 0 0 0 Total 10 22 15 4 0 0 51 Hours of calm in this stability class: 1 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 Braidwood Generating Station 65 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Period of Record: July - September 2020 Stability Class - Extremely Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 0 1 0 0 0 1 NNE 0 0 0 0 0 0 0 NE 0 5 1 0 0 0 6 ENE 1 4 1 0 0 0 6 E 0 0 0 0 0 0 0 ESE 0 5 1 0 0 0 6 SE 0 3 1 0 0 0 4 SSE 0 4 8 0 0 0 12 S 0 4 12 0 0 0 16 SSW 0 5 10 1 0 0 16 SW 0 4 11 1 0 0 16 WSW 0 2 8 1 0 0 11 W 0 3 6 1 0 0 10 WNW 0 3 5 1 0 0 9 NW 0 0 6 0 0 0 6 NNW 0 1 1 0 0 0 2 Variable 0 0 0 0 0 0 0 Total 1 43 72 5 0 0 121 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 66 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: July - September 2020 Stability Class - Moderately Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 0 1 0 0 0 1 NNE 0 1 1 0 0 0 2 NE 0 5 6 0 0 0 11 ENE 1 5 1 0 0 0 7 E 0 10 0 0 0 0 10 ESE 0 9 0 0 0 0 9 SE 0 4 0 0 0 0 4 SSE 0 10 2 0 0 0 12 S 0 10 5 1 0 0 16 SSW 0 6 6 1 0 0 13 SW 0 4 6 3 0 0 13 WSW 0 9 10 1 0 0 20 W 0 6 7 0 0 0 13 WNW 0 8 1 0 0 0 9 NW 1 7 3 0 0 0 11 NNW 0 5 3 0 0 0 8 Variable 0 0 0 0 0 0 0 Total 2 99 52 6 0 0 159 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 67 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: July - September 2020 Stability Class - Slightly Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 4 3 0 0 0 0 7 NNE 0 7 3 0 0 0 10 NE 1 7 8 0 0 0 16 ENE 3 14 0 0 0 0 17 E 2 17 0 0 0 0 19 ESE 1 6 0 0 0 0 7 SE 1 11 2 0 0 0 14 SSE 0 12 0 0 0 0 12 S 0 12 9 1 0 0 22 SSW 1 6 4 0 0 0 11 SW 2 7 7 1 0 0 17 WSW 0 8 8 0 0 0 16 W 1 15 5 0 0 0 21 WNW 0 8 5 2 0 0 15 NW 1 8 4 0 0 0 13 NNW 1 10 3 0 0 0 14 Variable 0 0 0 0 0 0 0 Total 18 151 58 4 0 0 231 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 68 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: July - September 2020 Stability Class - Neutral - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 3 13 5 0 0 0 21 NNE 5 24 14 2 0 0 45 NE 8 51 22 0 0 0 81 ENE 18 42 5 0 0 0 65 E 15 15 0 0 0 0 30 ESE 8 15 0 0 0 0 23 SE 4 20 2 0 0 0 26 SSE 2 18 9 0 0 0 29 S 3 16 26 4 0 0 49 SSW 0 7 18 20 1 0 46 SW 0 31 60 7 0 0 98 WSW 2 14 12 3 0 0 31 W 7 24 10 3 0 0 44 WNW 6 20 9 2 0 0 37 NW 4 15 8 1 0 0 28 NNW 6 26 11 0 0 0 43 Variable 0 0 0 0 0 0 0 Total 91 351 211 42 1 0 696 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 69 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: July - September 2020 Stability Class - Slightly Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 7 7 0 0 0 0 14 NNE 6 25 1 0 0 0 32 NE 9 15 0 0 0 0 24 ENE 26 13 1 0 0 0 40 E 28 1 0 0 0 0 29 ESE 9 16 0 0 0 0 25 SE 8 25 0 0 0 0 33 SSE 13 56 2 0 0 0 71 S 5 37 13 5 0 0 60 SSW 0 20 14 0 0 0 34 SW 5 26 38 0 0 0 69 WSW 4 25 1 2 0 0 32 W 10 21 1 0 0 0 32 WNW 13 13 2 0 0 0 28 NW 16 7 0 0 0 0 23 NNW 8 14 1 1 0 0 24 Variable 0 0 0 0 0 0 0 Total 167 321 74 8 0 0 570 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 70 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: July - September 2020 Stability Class - Moderately Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 11 2 0 0 0 0 13 NNE 4 5 0 0 0 0 9 NE 9 1 0 0 0 0 10 ENE 28 0 0 0 0 0 28 E 43 2 0 0 0 0 45 ESE 20 14 0 0 0 0 34 SE 8 2 0 0 0 0 10 SSE 7 8 0 0 0 0 15 S 6 0 0 0 0 0 6 SSW 3 7 1 0 0 0 11 SW 6 13 4 0 0 0 23 WSW 10 9 0 0 0 0 19 W 25 5 0 0 0 0 30 WNW 22 0 0 0 0 0 22 NW 8 1 0 0 0 0 9 NNW 9 0 0 0 0 0 9 Variable 0 0 0 0 0 0 0 Total 219 69 5 0 0 0 293 Hours of calm in this stability class: 4 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 71 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: July - September 2020 Stability Class - Extremely Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 5 0 0 0 0 0 5 NNE 13 0 0 0 0 0 13 NE 11 0 0 0 0 0 11 ENE 21 0 1 0 0 0 22 E 14 1 0 0 0 0 15 ESE 3 1 0 0 0 0 4 SE 3 0 0 0 0 0 3 SSE 2 0 0 0 0 0 2 S 0 0 0 0 0 0 0 SSW 2 0 0 0 0 0 2 SW 3 0 0 0 0 0 3 WSW 2 3 0 0 0 0 5 W 11 1 0 0 0 0 12 WNW 20 0 0 0 0 0 20 NW 9 0 0 0 0 0 9 NNW 3 0 0 0 0 0 3 Variable 0 0 0 0 0 0 0 Total 122 6 1 0 0 0 129 Hours of calm in this stability class: 5 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 72 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: July - September 2020 Stability Class - Extremely Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 0 0 1 0 0 1 NNE 0 1 0 0 0 0 1 NE 0 2 2 1 0 0 5 ENE 1 0 5 0 0 0 6 E 0 0 0 0 0 0 0 ESE 0 4 2 1 0 0 7 SE 0 3 1 1 0 0 5 SSE 0 1 7 3 0 0 11 S 0 1 10 9 0 0 20 SSW 0 2 12 4 0 0 18 SW 0 0 4 4 1 0 9 WSW 0 0 11 2 0 0 13 W 0 0 7 0 1 0 8 WNW 0 1 4 3 1 0 9 NW 0 0 0 6 0 0 6 NNW 0 0 1 1 0 0 2 Variable 0 0 0 0 0 0 0 Total 1 15 66 36 3 0 121 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 73 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: July - September 2020 Stability Class - Moderately Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 1 0 1 0 0 2 NNE 0 2 0 1 0 0 3 NE 0 2 1 5 0 0 8 ENE 1 5 2 0 0 0 8 E 0 6 8 0 0 0 14 ESE 0 2 3 0 0 0 5 SE 0 1 4 0 0 0 5 SSE 0 3 9 1 0 0 13 S 0 9 7 5 0 0 21 SSW 0 2 1 4 0 0 7 SW 0 2 9 4 1 0 16 WSW 0 7 9 1 1 0 18 W 0 2 6 1 0 0 9 WNW 0 5 5 0 0 0 10 NW 0 4 2 3 0 0 9 NNW 0 2 4 3 0 0 9 Variable 0 0 0 0 0 0 0 Total 1 55 70 29 2 0 157 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 2 Hours of missing stability measurements in all stability classes: 0 74 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: July - September 2020 Stability Class - Slightly Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 2 6 0 1 0 0 9 NNE 1 5 1 1 0 0 8 NE 0 7 1 8 0 0 16 ENE 3 10 4 1 0 0 18 E 0 15 7 0 0 0 22 ESE 1 3 2 0 0 0 6 SE 0 6 6 0 0 0 12 SSE 0 8 4 0 0 0 12 S 0 9 10 5 1 0 25 SSW 0 5 6 2 0 0 13 SW 0 3 6 3 0 0 12 WSW 0 7 7 3 0 0 17 W 0 10 6 2 0 0 18 WNW 0 7 4 1 0 2 14 NW 0 6 1 5 0 0 12 NNW 2 4 7 2 0 0 15 Variable 0 0 0 0 0 0 0 Total 9 111 72 34 1 2 229 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 2 Hours of missing stability measurements in all stability classes: 0 75 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: July - September 2020 Stability Class - Neutral - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 1 7 9 4 0 0 21 NNE 2 7 19 8 3 0 39 NE 1 12 26 17 0 0 56 ENE 4 26 20 5 0 0 55 E 3 30 14 0 0 0 47 ESE 3 4 7 3 0 0 17 SE 2 4 12 5 0 0 23 SSE 0 4 17 7 0 0 28 S 1 4 21 22 4 0 52 SSW 2 4 16 33 16 8 79 SW 3 10 40 18 3 0 74 WSW 2 5 17 4 2 1 31 W 2 11 19 4 2 1 39 WNW 1 10 13 3 2 0 29 NW 2 11 9 11 1 1 35 NNW 1 17 18 8 0 0 44 Variable 0 0 0 0 0 0 0 Total 30 166 277 152 33 11 669 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 27 Hours of missing stability measurements in all stability classes: 0 76 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: July - September 2020 Stability Class - Slightly Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 1 5 10 1 0 0 17 NNE 2 4 21 3 0 0 30 NE 0 4 20 0 0 0 24 ENE 1 18 22 1 0 0 42 E 2 9 14 0 0 0 25 ESE 0 3 10 3 0 0 16 SE 1 4 17 6 0 0 28 SSE 1 13 39 7 0 0 60 S 1 10 39 15 6 0 71 SSW 0 7 25 18 0 0 50 SW 1 9 36 34 0 0 80 WSW 0 4 14 3 1 1 23 W 0 4 24 1 0 0 29 WNW 0 6 14 4 0 0 24 NW 0 4 14 3 0 1 22 NNW 2 3 23 1 0 0 29 Variable 0 0 0 0 0 0 0 Total 12 107 342 100 7 2 570 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 77 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: July - September 2020 Stability Class - Moderately Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 3 2 1 0 0 6 NNE 0 4 4 2 0 0 10 NE 0 3 8 1 0 0 12 ENE 0 13 7 0 0 0 20 E 0 5 22 5 0 0 32 ESE 0 3 23 10 0 0 36 SE 0 5 8 7 0 0 20 SSE 0 1 3 1 0 0 5 S 0 7 11 1 0 0 19 SSW 0 10 10 1 0 0 21 SW 1 9 13 8 0 0 31 WSW 1 4 14 0 0 0 19 W 0 2 9 2 0 0 13 WNW 0 4 23 1 0 0 28 NW 1 2 10 1 0 0 14 NNW 1 3 6 1 0 0 11 Variable 0 0 0 0 0 0 0 Total 4 78 173 42 0 0 297 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 78 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: July - September 2020 Stability Class - Extremely Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 7 5 0 0 0 12 NNE 0 2 3 0 0 0 5 NE 1 2 8 0 0 0 11 ENE 0 7 3 0 0 0 10 E 0 5 5 0 0 0 10 ESE 0 3 2 2 0 0 7 SE 1 3 0 1 0 0 5 SSE 0 3 2 0 0 0 5 S 0 6 0 0 0 0 6 SSW 0 14 5 0 0 0 19 SW 1 4 0 0 0 0 5 WSW 0 0 2 0 0 0 2 W 1 2 3 5 0 0 11 WNW 0 1 7 0 0 0 8 NW 0 4 6 0 0 0 10 NNW 0 2 6 0 0 0 8 Variable 0 0 0 0 0 0 0 Total 4 65 57 8 0 0 134 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 Braidwood Generating Station 79 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Period of Record: October - December2020 Stability Class - Extremely Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 0 0 0 0 0 0 NNE 0 0 0 0 0 0 0 NE 0 0 0 0 0 0 0 ENE 0 0 0 0 0 0 0 E 0 0 0 0 0 0 0 ESE 0 0 0 0 0 0 0 SE 0 0 0 0 0 0 0 SSE 0 1 0 0 0 0 1 S 0 0 0 0 0 0 0 SSW 0 0 1 0 0 0 1 SW 0 0 0 0 0 0 0 WSW 0 0 0 1 0 0 1 W 0 0 0 2 0 0 2 WNW 0 0 8 2 0 0 10 NW 0 6 7 1 0 0 14 NNW 0 2 1 0 0 0 3 Variable 0 0 0 0 0 0 0 Total 0 9 17 6 0 0 32 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 80 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: October - December2020 Stability Class - Moderately Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 1 1 0 0 0 2 NNE 0 1 0 0 0 0 1 NE 0 0 0 0 0 0 0 ENE 0 0 0 0 0 0 0 E 0 4 0 0 0 0 4 ESE 0 1 0 0 0 0 1 SE 0 0 0 0 0 0 0 SSE 0 0 1 0 0 0 1 S 0 0 1 4 1 0 6 SSW 0 0 6 7 0 0 13 SW 0 0 11 1 0 0 12 WSW 0 3 2 1 0 0 6 W 0 1 8 3 0 0 12 WNW 0 6 1 2 0 0 9 NW 0 3 6 3 0 0 12 NNW 0 1 5 0 0 0 6 Variable 0 0 0 0 0 0 0 Total 0 21 42 21 1 0 85 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 81 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: October - December2020 Stability Class - Slightly Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 4 0 0 0 0 4 NNE 0 3 0 0 0 0 3 NE 0 2 0 0 0 0 2 ENE 0 5 0 0 0 0 5 E 0 8 0 0 0 0 8 ESE 0 0 0 0 0 0 0 SE 0 1 0 0 0 0 1 SSE 0 0 4 0 0 0 4 S 0 0 3 8 0 1 12 SSW 0 1 8 5 1 0 15 SW 0 2 10 7 0 0 19 WSW 0 1 5 1 0 0 7 W 0 7 5 1 0 0 13 WNW 0 4 11 1 0 0 16 NW 0 5 2 0 0 0 7 NNW 0 5 5 0 0 0 10 Variable 0 0 0 0 0 0 0 Total 0 48 53 23 1 1 126 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 82 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: October - December2020 Stability Class - Neutral - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 9 34 21 7 0 0 71 NNE 3 49 12 3 0 0 67 NE 3 39 20 0 0 0 62 ENE 8 40 13 0 0 0 61 E 6 14 0 0 0 0 20 ESE 2 14 5 0 0 0 21 SE 0 9 30 6 0 0 45 SSE 0 13 24 13 0 0 50 S 1 7 27 63 12 1 111 SSW 1 1 20 31 19 4 76 SW 1 9 57 10 3 1 81 WSW 1 19 27 2 2 0 51 W 3 35 22 15 17 2 94 WNW 6 40 66 24 3 0 139 NW 12 36 21 1 0 0 70 NNW 9 46 38 7 0 0 100 Variable 0 0 0 0 0 0 0 Total 65 405 403 182 56 8 1119 Hours of calm in this stability class: 1 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 83 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: October - December2020 Stability Class - Slightly Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 7 16 1 0 0 0 24 NNE 9 8 2 0 0 0 19 NE 3 3 0 0 0 0 6 ENE 8 7 0 0 0 0 15 E 14 3 0 0 0 0 17 ESE 9 18 1 0 0 0 28 SE 0 25 8 0 0 0 33 SSE 1 38 13 2 0 0 54 S 1 16 29 16 0 0 62 SSW 0 6 48 19 1 0 74 SW 0 19 61 5 0 0 85 WSW 1 36 10 1 0 0 48 W 14 25 10 2 0 0 51 WNW 10 16 8 5 0 0 39 NW 12 10 2 0 0 0 24 NNW 6 8 1 0 0 0 15 Variable 0 0 0 0 0 0 0 Total 95 254 194 50 1 0 594 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 84 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: October - December2020 Stability Class - Moderately Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 4 0 0 0 0 0 4 NNE 3 0 0 0 0 0 3 NE 3 1 0 0 0 0 4 ENE 4 0 0 0 0 0 4 E 5 4 0 0 0 0 9 ESE 6 5 0 0 0 0 11 SE 6 0 0 0 0 0 6 SSE 1 1 0 0 0 0 2 S 3 2 0 0 0 0 5 SSW 3 9 3 0 0 0 15 SW 0 3 4 0 0 0 7 WSW 4 12 2 0 0 0 18 W 21 29 0 0 0 0 50 WNW 17 10 0 0 0 0 27 NW 4 0 0 0 0 0 4 NNW 4 0 0 0 0 0 4 Variable 0 0 0 0 0 0 0 Total 88 76 9 0 0 0 173 Hours of calm in this stability class: 1 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 85 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: October - December2020 Stability Class - Extremely Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 34 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 3 0 0 0 0 0 3 NNE 2 0 0 0 0 0 2 NE 4 0 0 0 0 0 4 ENE 7 0 0 0 0 0 7 E 9 0 0 0 0 0 9 ESE 8 0 0 0 0 0 8 SE 5 1 0 0 0 0 6 SSE 1 0 0 0 0 0 1 S 2 0 0 0 0 0 2 SSW 1 1 0 0 0 0 2 SW 2 2 1 0 0 0 5 WSW 1 4 0 0 0 0 5 W 5 0 0 0 0 0 5 WNW 5 0 0 0 0 0 5 NW 8 0 0 0 0 0 8 NNW 4 0 0 0 0 0 4 Variable 0 0 0 0 0 0 0 Total 67 8 1 0 0 0 76 Hours of calm in this stability class: 1 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 86 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: October - December2020 Stability Class - Extremely Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 0 0 0 0 0 0 NNE 0 0 0 0 0 0 0 NE 0 0 0 0 0 0 0 ENE 0 0 0 0 0 0 0 E 0 0 0 0 0 0 0 ESE 0 0 0 0 0 0 0 SE 0 0 0 0 0 0 0 SSE 0 1 0 0 0 0 1 S 0 0 0 0 0 0 0 SSW 0 0 0 1 0 0 1 SW 0 0 0 0 0 0 0 WSW 0 0 0 0 1 0 1 W 0 0 0 1 1 0 2 WNW 0 0 3 3 2 0 8 NW 0 0 10 6 0 1 17 NNW 0 0 2 0 0 0 2 Variable 0 0 0 0 0 0 0 Total 0 1 15 11 4 1 32 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 87 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: October - December2020 Stability Class - Moderately Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 0 3 0 0 0 3 NNE 0 0 0 0 0 0 0 NE 0 0 0 0 0 0 0 ENE 0 0 0 0 0 0 0 E 0 2 1 0 0 0 3 ESE 0 1 1 0 0 0 2 SE 0 0 0 0 0 0 0 SSE 0 0 1 0 0 0 1 S 0 0 1 0 4 1 6 SSW 0 0 2 8 4 1 15 SW 0 0 6 2 1 0 9 WSW 0 1 5 1 0 0 7 W 0 1 3 7 1 0 12 WNW 0 1 5 1 1 1 9 NW 0 0 5 4 0 3 12 NNW 0 0 4 2 0 0 6 Variable 0 0 0 0 0 0 0 Total 0 6 37 25 11 6 85 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 88 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: October - December2020 Stability Class - Slightly Unstable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 2 0 0 0 0 2 NNE 0 2 2 0 0 0 4 NE 0 2 0 0 0 0 2 ENE 0 3 1 0 0 0 4 E 0 2 6 1 0 0 9 ESE 0 1 0 0 0 0 1 SE 0 0 0 0 0 0 0 SSE 0 0 4 0 0 0 4 S 0 0 2 4 4 1 11 SSW 0 0 2 9 5 2 18 SW 0 1 5 9 2 0 17 WSW 0 0 2 4 0 0 6 W 0 2 8 4 1 0 15 WNW 0 1 5 4 3 0 13 NW 0 2 3 3 1 0 9 NNW 0 4 3 3 1 0 11 Variable 0 0 0 0 0 0 0 Total 0 22 43 41 17 3 126 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 89 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: October - December2020 Stability Class - Neutral - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 4 14 23 16 7 0 64 NNE 2 20 30 10 3 0 65 NE 2 19 27 19 0 0 67 ENE 2 14 26 8 0 0 50 E 4 5 20 1 0 0 30 ESE 0 5 4 7 3 0 19 SE 0 1 10 27 5 2 45 SSE 0 3 12 20 17 3 55 S 0 5 6 20 42 28 101 SSW 0 2 3 28 30 30 93 SW 1 3 28 32 4 5 73 WSW 2 7 26 13 5 2 55 W 1 16 21 11 8 23 80 WNW 0 18 32 45 20 16 131 NW 2 11 20 34 11 1 79 NNW 1 32 36 34 10 0 113 Variable 0 0 0 0 0 0 0 Total 21 175 324 325 165 110 1120 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 90 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: October - December2020 Stability Class - Slightly Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 2 4 13 3 0 0 22 NNE 1 5 5 5 0 0 16 NE 2 1 3 2 0 0 8 ENE 1 4 7 0 0 0 12 E 2 2 11 1 0 0 16 ESE 1 0 6 7 0 0 14 SE 0 2 15 18 2 0 37 SSE 0 2 15 32 1 0 50 S 0 3 11 23 15 2 54 SSW 0 2 11 59 23 8 103 SW 1 3 16 45 10 0 75 WSW 0 5 19 21 1 0 46 W 1 2 14 19 4 0 40 WNW 0 8 12 16 7 2 45 NW 0 4 14 10 0 0 28 NNW 2 8 15 3 0 0 28 Variable 0 0 0 0 0 0 0 Total 13 55 187 264 63 12 594 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 91 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: October - December2020 Stability Class - Moderately Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 0 0 3 1 0 0 4 NNE 0 2 2 0 0 0 4 NE 0 0 2 0 0 0 2 ENE 0 0 0 0 0 0 0 E 0 3 1 0 0 0 4 ESE 0 0 4 4 0 0 8 SE 0 1 4 1 0 0 6 SSE 0 0 5 0 0 0 5 S 3 3 2 0 0 0 8 SSW 0 2 5 1 2 0 10 SW 1 5 6 6 0 0 18 WSW 1 0 4 4 0 0 9 W 2 2 13 9 0 0 26 WNW 0 2 26 14 0 0 42 NW 0 1 13 2 0 0 16 NNW 0 1 11 0 0 0 12 Variable 0 0 0 0 0 0 0 Total 7 22 101 42 2 0 174 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 92 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

Braidwood Generating Station Period of Record: October - December2020 Stability Class - Extremely Stable - 199Ft-30Ft Delta-T (F)

Winds Measured at 203 Feet Wind Speed (in mph)

Wind Direction 1-3 4-7 8-12 13-18 19-24 > 24 Total N 1 4 7 0 0 0 12 NNE 0 3 2 0 0 0 5 NE 0 1 3 0 0 0 4 ENE 1 0 0 0 0 0 1 E 0 2 0 0 0 0 2 ESE 0 3 1 1 0 0 5 SE 0 3 2 2 0 0 7 SSE 0 0 1 0 0 0 1 S 1 4 1 0 0 0 6 SSW 0 5 4 0 0 0 9 SW 3 2 1 1 0 0 7 WSW 0 0 0 5 0 0 5 W 0 0 2 2 0 0 4 WNW 0 0 0 3 0 0 3 NW 0 0 0 0 0 0 0 NNW 0 2 4 0 0 0 6 Variable 0 0 0 0 0 0 0 Total 6 29 28 14 0 0 77 Hours of calm in this stability class: 0 Hours of missing wind measurements in this stability class: 0 Hours of missing stability measurements in all stability classes: 0 93 of 94

BRAIDWOOD NUCLEAR POWER STATION RADIOACTIVE EFFLUENT RELEASE REPORT FOR 2020 UNIT 1, UNIT 2 and ISFSI (Docket Numbers 50-456, 50-457 and 72-73)

APPENDIX D: ERRATA There were two errors identified in 2020.

a. An error was identified by the ODCM chemist with the H3 (tritium) activity used in permit L-20190528-052. For permit L-20190528-052, the original H3 activity of 1.17 E-4 uCi/ml (microcuries per milliliter) was used rather than the H3 difference of 2.99 E-05 uCi/ml. Using the original H3 activity in the post-release permit rather than the difference value resulted in a conservatively higher H3 activity being calculated and documented in the post-release permit. Re-analysis of the post release permit with the value corrected adjusted the 2019 curies released value from CWBD H3 from 599 curies to 287 curies.

IR 04368302

b. Braidwood was notified by Mirion (OpenEMS effluent permit vendor) that OpenEMS was not calculating liquid doses IAW Braidwood's Offsite Dose Calculation Manual (ODCM). Braidwood ODCM equation A-18 specifies that the "Dilution Flow" used in the "Near Field Average Dilution Factor" should be the "Dilution Water Flow During Period of Interest" in gpm. Previously OpenEMS was using the dilution volume (in gallons) for a larger time frame corresponding to that of the CWBD permit when the recalc.exe was used or if a permit is reanalyzed. OpenEMS is used to document and survey results that is then put into the annual report (ARERR). This is considered a minor violation of 10CFR20.1302a due to the consequence being 1 to 2 times an increase in dose reported. Below are actual doses calculated after permits were reprocessed. No dose limits were exceeded based on Appendix I limits from 10CFR50. Appendix I limits are 3 mRem annual total body and 10 mRem annual organ dose for liquid effluents per unit (6 mRem and 20mRem per year combined unit). See below for dose after all permits were recalculated. Doses were validated using an excel spreadsheet and was verified by ODCM Chemist and Mirion Technologies. IR 04353041 2017 Before reanalysis: Total Body 7.78E-02, Organ 7.88E-02 2018 Before reanalysis: Total Body 7.81E-02, Organ 7.96E-02 2019 Before reanalysis : Total Body 1.03E-01, Organ 1.04E-01 2017 After reanalysis: Total Body 1.59E-01, Organ 1.80E-01 2018 After reanalysis: Total Body 1.51E-01, Organ 1.60E-01 2019 After reanalysis: Total Body 1.95E-01, Organ 2.02E-01 94 of 94