Text

Annual Radiological Environmental Operating Reports for 2024
	ML25132A307
Person / Time
Site:	Hatch
Issue date:	05/12/2025
From:	Coleman J; Southern Nuclear Operating Co
To:	; Office of Nuclear Reactor Regulation, Document Control Desk
References
	NL-25-0181
	Download: ML25132A307 (1)
	v • d • e

A Southern Nuclear May 12, 2025 Docket Nos.: 50-321 50-366 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Regulatory Affairs Edwin I. Hatch Nuclear Plant - Units 1 & 2 3535 Colonnade Parkway Birmingham, AL 35243 205 992 5000 NL-25-0181 Annual Radiological Environmental Operating Reports for 2024 Ladies and Gentlemen:

In accordance with section 5.6.2 of the Edwin I. Hatch Nuclear Plant (HNP)-Units 1 & 2 Technical Specifications, Southern Nuclear Operating Company hereby submits the enclosed Annual Radiological Environmental Operating Report for 2024.

This letter contains no NRC commitments. If you have any questions, please contact Ryan Joyce at 205.992.6468.

Respectfully submitted, Jamie M. Coleman Regulatory Affairs Director JMC/btr/cbg

Enclosure:

HNP Annual Radiological Environmental Operating Report for 2024 cc:

Regional Administrator, Region II NRR Project Manager - Hatch Senior Resident Inspector-Hatch RTYPE: CHA02.004 State of Georgia Department of Natural Resources

Edwin I. Hatch Nuclear Plant Unit 1 & 2 Enclosure to NL-25-0181 HNP Annual Radiological Environmental Operating Report for 2024

._ Southern Nuclear Hatch Nuclear Plant 2024 Annual Radiological Environmental Operating Report

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 1 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant TABLE OF CONTENTS 1.0 LIST OF ACRONYMS AND DEFINITIONS................................................................................ 3 2.0 EXECUTIVE

SUMMARY

............................................................................................................ 5 2.1 Summary Of

Conclusions:

.............................................................................................. 5

3.0 INTRODUCTION

........................................................................................................................ 6 4.0 SITE DESCRIPTION AND SAMPLE LOCATIONS..................................................................... 7 5.0 MAPS OF COLLECTION SITES.............................................................................................. 14 6.0 REPORTING LEVELS FOR RADIOACTIVITY CONCENTRATIONS IN ENVIRONMENTAL SAMPLES................................................................................................. 17 7.0 SAMPLING PROGRAM, PROGRAM MODIFICATION AND INTERPRETATION OF RESULTS................................................................................................................................ 18 7.1 Environmental Direct Radiation Dosimetry Sample Results.......................................... 19 7.2 Air Particulate and Radioiodine Sample Results........................................................... 22 7.3 Waterborne Sample Results......................................................................................... 24 7.4 Ingestion Pathway Sample Results............................................................................... 26 8.0 LAND USE CENSUS EXPOSURE PATHWAY........................................................................ 28 9.0 SAMPLE DEVIATIONS, ANOMALIES AND UNAVAILABILITY................................................ 29 10.0 OTHER SUPPLEMENTAL INFORMATION............................................................................. 30 10.1 NEI 07-07 Onsite Radiological Groundwater Monitoring Program................................. 30 10.2 Corrections to Previous Reports................................................................................... 30 11.0 BIBLIOGRAPHY...................................................................................................................... 31 TABLES Table 1, Radiological Environmental Sampling Program - Exposure Pathway - Direct Radiation......... 8 Table 2, Radiological Environmental Sampling Program - Exposure Pathway - Airborne...................... 9 Table 3, Radiological Environmental Sampling Program - Exposure Pathway - Waterborne............... 10 Table 4, Radiological Environmental Sampling Program - Exposure Pathway - Ingestion................... 11 Table 5, REMP Sampling Locations - Direct Radiation........................................................................ 12 Table 6, Reporting Levels for Radioactivity Concentrations in Environmental Samples....................... 17 Table 7, Minimum Detectable Concentration (MDC)............................................................................ 17 Table 8, Land Use Census - Nearest Residence within 5 miles.......................................................... 28 Table 9, Sample Deviation Summary................................................................................................... 29

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 2 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant FIGURES Figure 1, Potential exposure pathways to Members of the Public due to Plant Operations.................... 6 Figure 2, REMP Sample Locations (Near Field/Site Boundary)........................................................... 14 Figure 3, REMP Sample Locations (Far Field)..................................................................................... 15 Figure 4, REMP Sample Locations (Onsite)......................................................................................... 16 Figure 5, Average Quarterly Dose from Direct Radiation in Select Locations....................................... 20 Figure 6: Air Particulate: Analysis for Gross Beta, Average Mean for All Indicator Vs. Control............. 23 Figure 7: Surface Water Tritium Results.............................................................................................. 24 ATTACHMENTS, Data Table Summary.................................................................................................... 33, Complete Data Table for All Analysis Results Obtained In 2024................................... 37, Cross Check lntercomparison Program......................................................................... 86, Environmental Direct Radiation Dosimetry Sample Results.......................................... 89

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 3 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 1.0 LIST OF ACRONYMS AND DEFINITIONS

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

16.

17.

18.

Airborne Activity Sampling: Continuous sampling of air through the collection of particulates and radionuclldes on filter media.

ARERR: Annual Radioactive Effluent Release Report AREOR: Annual Radiological Environmental Operating Report BWR: Boiling Water Reactor Composite Sample: A series of single collected portions (aliquots) analyzed as one sample. The aliquots making up the sample are collected at time intervals that are very short compared to tfle composite period.

Control: A sampling station in a location not likely to be affected by plant effluents due to its distance and/or direction from the station.

Curie (Ci): A measure of radioactivity; equal to 3.7 x 1010 disintegrations per second, or 2.22 x 1012 disintegrations per minute.

Direct Radiation Monitoring: The measurement of radiation dose at various distances from the plant is assessed using Thermoluminescent dosimeters, Optical Stimulated Luminance dosimeters and pressurized ionization chambers.

fCi/m3: femto curies per cubic meter.

Grab Sample: A single discrete sample drawn at one point in time.

Indicator: A sampling location that is likely to be affected by plant effluents due to its proximity and/or direction from the plant.

Ingestion Pathway: The ingestion pathway includes milk, fish, drinking water and garden produce. Also sampled (under special circumstances) are other media such as vegetation and animal products such as eggs and meat when additional information about particular radionuclides is needea.

ISFSI: Independent Spent Fuel Storage Installation Lower Limit of Detection (LLD):. An a priori measure of the detection capability of a radiochemistry measurement based on instrument setup, calibration, background, decay time, and sample volume. An LLD is expressed as an activity concentration. The MDA is used for reporting results. LLD are specified by a regulator, such as the NRC and are typically listed in the ODCM.

MDA: Minimum Detectable Activity. For radiochemistry instruments, the MDA is the a posteriori minimum concentration that a counting system detects. The smallest concentration or activity of radioactive material in a sample that will yield a net count above instrument background and that is detected with 95%

probability, with only five % probability of falsely concluding that a blank observation represents a true signal.

MDC: Minimum Detectable Concentration. Essentially synonymous with MDA for the purposes of radiological monitoring.

Mean: The average, i.e., the sum of results divided by the number of results.

Microcurie: 3.7 x 104 disintegrations per second, or 2.22 x106 disintegrations per minute.

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 4 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant

19.

MWe: Megawatts Electric

20.

NA: Not Applicable

21.

NEI: Nuclear Energy Institute

22.

NIST: National Institute of Standards and Technology.

23.

NPDES: National Pollutant Discharge Elimination System.

24.

SPDES: State Pollution Discharge Elimination System

25.

NRC: Nuclear Regulatory Commission

26.

ODCM: Offsite Dose Calculation Manual

27.

OSLO: Optical Stimulated Luminance Dosimeter

28.

pCi/L: picocuries / Liter

29.

Protected Area: An area encompassed by physical barriers and to which access is controlled.

30.

PWR: Pressurized Water Reactor

31.

REMP: Radiological Environmental Monitoring Program

32.

Restricted Area: An area, access to which is limited by the licensee for the purpose of protecting individuals against undue risks from exposure to radiation and radioactive materials.

33.

SLC: Selected Licensee Commitment

34.

SA: Sample Anomalies

35.

SD: Sample Deviation

36.

SPDES: State Pollutant Discharge Elimination System.

37.

SW: Surface Water

38.

TRM: Technical Requirement Manual

39.

TS: Technical Specification

40.

US: Unavailable Samples

41.

NDM: Non-Detectable Measurement

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 5 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 2.0 EXECUTIVE

SUMMARY

The Hatch Nuclear Plant Radiological Environmental Monitoring Program (REMP) was established prior to the station becoming operational to provide information on background radiation present in the area. The goal of the HNP REMP is to evaluate the impact of the station on the environment. Environmental samples from different media are monitored as part of the program in accordance with the Offsite Dose Calculation Manual (ODCM). The program compares data from indicator locations near the plant, to control locations farther away from the site to assess operation impacts.

The Annual Radiological Environmental Operating Report (AREOR) provides data obtained through analyses of environmental samples collected at HNP for the reporting period of January 1st through December 31st, 2024. During that period 867 analyses were performed on 833 samples. In assessing all the data gathered for this report and comparing these results with preoperational data and/or 10-year average values, it was concluded that the operation of HNP, did not result in detection of plant related radionuclides in the environment.

2.1 Summary Of

Conclusions:

No measurable activities above background levels were detected. All values were consistent with historical results which indicate no adverse radiological environmental impacts associated with the operation of HNP. Naturally occurring radionuclides are present in the Earth's crust and atmosphere and exists in detectable quantities throughout the world. It is common to detect natural occurring radionuclides in many of the samples collected for REMP. Some examples of naturally occurring radionuclides that are frequently seen in samples are potassium-40, beryllium-?, actinium-228 (present as a decay product of radium-228), and radium-226. Additionally, some relatively long-lived anthropogenic radioisotopes, such as strontium-90 and cesium-137, are also seen in some REMP samples; these radionuclides exist in measurable quantities throughout the world as a result of fallout from historic atmospheric nuclear weapons testing. Detailed information on the exposure of the U.S. population to ionizing radiation can be found in NCRP Report No. 160 [1 ].

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 6 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant

3.0 INTRODUCTION

The Radiological Environmental Monitoring Program (REMP) provides data on measurable levels of radiation and radioactive materials in the environment. This program also evaluates the relationship between quantities of radioactive materials released from the plant and resultant doses to individuals from principal pathways of exposure. In this capacity, REMP provides a check on the effluent release program and dispersion modeling to ensure that concentrations in the environment due to radioactive effluents conform to the "As Low as Is Reasonably Achievable" (ALARA) design objectives of 10 CFR 50, Appendix I [2], and implements the requirements of Section IV.B.2 and IV.B.3 of Appendix I. REMP is designed to conform to the Nuclear Regulatory Commission (NRC) Regulatory Guide 4.1 [3], NUREG 1301 /1302 [4] [5],

and the 1979 NRC Branch Technical Position [6].

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* * * : Behavior of radionuclides Figure 1, Potential exposure pathways to Members of the Public due to Plant Operations [7]

Quality assurance aspects of the sampling program and OSLO data collection are conducted in accordance with Regulatory Guides 4.15 [8] and 4.13 [9]. REMP also adheres to the requirements of HNP Technical Specifications, and Offsite Dose Calculation Manual (ODCM). These governing documents dictate the environmental

sampling, sample analysis protocols, data reporting and quality assurance requirements for the environmental monitoring program.

The Annual Radiological Environmental Operating Report provides summaries of the environmental data from exposure pathways, interpretations of the data, and analyses of trends of the results. Routinely monitored pathways include ingestion, inhalation, and direct radiation. Routes of exposure are based on site specific information such as meteorology, receptor locations, and water usage around the plant.

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 7 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 4.0 SITE DESCRIPTION AND SAMPLE LOCATIONS Hatch Nuclear Plant is a commercial nuclear power plant that is owned by Georgia Power Company (GPC), Oglethorpe Power Corporation, the Municipal Electric Authority of Georgia, and Dalton Utilities. The plant is in Appling County, Georgia on the southwest side of the Altamaha River near Baxley, Georgia. Unit 1, a General Electric Company Boiling Water Reactor (BWR) with a licensed core thermal output of 2,804 Megawatts (MWt), began commercial operation on December 31, 1975. Unit 2, also a General Electric Company BWR rated for 2,804 MWt, began commercial operation on September 5, 1979. The pre-operational stage of the REMP began with the establishment and activation of the environmental monitoring stations in January of 1972. The operational stage of the REMP began on September 12, 197 4, with Unit 1 initial criticality. HNP sampling media are selected based on site specific information such as meteorology, receptor locations, and water usage around the plant. Sampling and analysis frequencies are documented in the Offsite Dose Calculation Manual and site procedures. Required sampling, analysis frequencies and location of sample collected are captured in the following tables and figures:

Table 1, Radiological Environmental Sampling Program - Exposure Pathway

- Direct Radiation Table 2, Radiological Environmental Sampling Program - Exposure Pathway -

Airborne Table 3, Radiological Environmental Sampling Program - Exposure Pathway -

Waterborne Table 4, Radiological Environmental Sampling Program - Exposure Pathway -

Ingestion Table 5, REMP Sampling Locations - Direct Radiation Figure 2, REMP Sample Locations (Near Field/Site Boundary)

Figure 3, REMP Sample Locations (Far Field)

Figure 4, REMP Sample Locations (Onsite)

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 8 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant RADIOLOGICAL ENVIRONMENTAL SAMPLING PROGRAM REQUIREMENTS Table 1, Radiological Environmental Sampling Program - Exposure Pathway - Direct Radiation Sample Location (Location Sampling Collection/

Requirement Number) Description, Distance, Frequency Type and Frequency of Analyses and Direction Direct Radiation 37 Routine monitoring stations See Table 5 Quarterly Gamma dose/Quarterly

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 9 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant Table 2, Radiological Environmental Sampling Program - Exposure Pathway - Airborne Sample Location (Location Sampling Collection/

Requirement Number) Description, Distance, Frequency Type and Frequency of Analyses and Direction Airborne Radioiodine and Particulates1 Samples from 6 locations (103) Inner Ring NE 1.8 mi.

Continuous sampler Particulate sampler: Analyze for gross beta (107) Inner Ring SE 1.2 mi.

operation with sample radioactivity ~ 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> following filter change/

(112) Inner Ring WSW 1 mi.

collection weekly Weekly. Perform gamma isotopic analysis on (116) Inner Ring NNW 1.6 mi.

each sample when gross beta activity is > 10 (304) State Prison ENE 11.2 mi.

times the yearly mean of control samples.

(309) Baxley Substation S 10 mi.

Perform gamma isotopic analysis on composite sample (by location)/Quarterly. Radioiodine canister: 1-131 analysis/Weekly.

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 10 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant Table 3, Radiological Environmental Sampling Program - Exposure Pathway - Waterborne Sample Location (Location Sampling Collection/

Requirement Number) Description, Distance, Frequency Type and Frequency of Analyses and Direction Surface Water3 One sample upstream (control) and (170) Upstream WNW - 0.6 RM Composite sample over one-Gamma isotopic2 /Monthly, One sample downstream (indicator) from intake month period 1 (172) Downstream E - 3.0 RM from Composite for H-3 /Quarterly intake Drinking Water3,4 From each of the one to three nearest (170) Upstream WNW - 0.6 RM River water collected near the 1-131 analysis on each sample when water supplies which could be from intake intake will be a composite biweekly collections are required. Gross affected by HNP discharge:

(172) Downstream E - 3.0 RM from sample; the finished water will beta and gamma isotopic analysis on One sample of river water near the intake be a grab sample. These each sample; composite (by location) for samples will be collected tritium analysis/Quarterly.

intake and monthly unless the calculated One sample of finished water dose due to consumption of the water is greater than 1 mrem/year; then the collection will be biweekly.

The collections may revert to monthly should the calculated doses become less than 1 mrem/year Sediment from Shoreline7*8 Samples from 2 locations (170) Upstream WNW - 0.6 RM Semiannually Gamma isotopic2 /Semiannually from intake (172) Downstream E - 3.0 RM from intake

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 11 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant Table 4, Radiological Environmental Sampling Program - Exposure Pathway - Ingestion Sample Location (Location Sampling Collection/

Requirement Number) Description, Distance, Frequency Type and Frequency of Analyses and Direction Milk5 Sample from 1 location (304) State Prison ENE 10.3 mi.

Biweekly Gamma isotopic2*7 and 1-131 analysis/Biweekly Fish and lnvertebrates6*8 Samples from 2 locations (170) Upstream WNW~ 0.6 RM Semiannually during Gamma isotopic2 analysis on edible portions, from intake spawning season each sample/Semiannually (172) Downstream E ~ 3.0 RM from intake Grass or Leatl Vegetation Samples from 3 locations (106) Inner Ring ESE 1.1 mi.

Monthly during growing Gamma isotopic anaylsis2-7/Monthly (112) Inner Ring WSW 1 mi.

season (416) Emergency News Center NNW 21.0 mi Notes:

1.

Composite sample aliquots were collected at time intervals are very short (e.g., hourly) relative to the compositing period (e.g., monthly) to ensure obtaining a representative sample.

2.

Gamma isotopic analysis means the identification and quantification of gamma-emitting radionuclides that may be attributable to the effluents from the facility.

3.

If it is found that river water downstream of the plant is used for drinking, drinking water samples will be collected and analyzed as specified herein.

4.

A survey shall be conducted annually at least 50 river miles downstream of the plant to identify those who use water from the Altamaha River for drinking. No new drinking water withdrawal permits were issued in 2024.

5.

Up to three sampling locations within five miles and in different sectors will be used as available. In addition, one or more control locations beyond 10 miles will be used.

6.

Commercially or recreationally important fish may be sampled. Clams may be sampled if difficulties are encountered in obtaining sufficient fish samples.

7.

If the gamma isotopic analysis is not sensitive enough to meet the Minimum Detectable Concentration (MDC) for 1-131, a separate analysis for 1-131 may be performed.

8.

Station 170 was located approximately 0.6 river miles upstream of the intake structure for river water, 1.1 river miles for sediment and clams, and 1.5 river miles for fish. Station 172 was located approximately 3.0 river miles downstream of the discharge structure for river water, sediment and clams, and 1. 7 river miles for fish. The locations from which river water and sediment may be taken can be sharply defined. However, the sampling locations for clams often have to be extended over a wide area to obtain a sufficient quantity. High water adds to the difficulty in obtaining clam samples and may also make an otherwise suitable location for sediment sampling unavailable. A stretch of the river of a few miles or so was generally needed to obtain adequate fish samples. The mile locations given above represent approximations of the locations where samples were collected.

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 12 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant Table 5, REMP Sampling Locations - Direct Radiation Site#

Location Type Sector Distance (miles)

Description 101 Indicator Station N

1.9 Inner Ring 102 Indicator Station NNE 2.5 Inner Ring.

103 Indicator Station NE 1.8 Inner Ring 104 Indicator Station ENE 1.6 Inner Ring 105 Indicator Station E

3.7 Inner Ring 106 Indicator Station EESE 1.1 Inner Ring 107 Indicator Station SE 1.2 Inner Ring 108 Indicator Station SSE 1.6 Inner Ring 109 Indicator Station s

0.9 Inner Ring.

110 Indicator Station SSW 1.0 Inner Ring 111 Indicator Station SW 0.9 Inner Ring 112 Indicator Station WSW 1.0 Inner Ring 113 Indicator Station w

1.1 Inner Ring 114 Indicator Station WNW 1.2 Inner Ring 115 Indicator Station NW 1.1 Inner Ring 116 Indicator Station NNW 1.6 Inner Ring 304 Control Station ENE 11.2 State Prison 309 Control Station s

10 Baxley Substation 416 Control Station NNW 21.0 Emergency News Center 64 Community Station WNW 0.8 Roadside Park 201 Community Station N

5 Outer Ring 202 Community Station NNE 4.9 Outer Ring 203 Community Station NE 5

Outer Ring 204 Community Station ENE 5

Outer Ring 205 Community Station E

7.2 Outer Ring 206 Community Station ESE 4.8 Outer Ring

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 13 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant Table 5, REMP Sampling Locations - Direct Radiation Site#

Location Type Sector Distance (miles)

Description 207 Community Station SE 4.3 Outer Ring 208 Community Station SSE 4.8 Outer Ring 209 Community Station s

4.4 Outer Ring 210 Community Station SSW 4.3 Outer Ring 211 Community Station SW 4.7 Outer Ring 212 Community Station WSW 4.4 Outer Ring 213 Community Station w

4.3 Outer Ring 214 Community Station WNW 5.4 Outer Ring 215 Community Station NW 4.4 Outer Ring 216 Community Station WNNW 4.8 Outer Ring 301 Community Station N

8.0 Toombs Central School

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 14 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 5.0 MAPS OF COLLECTION SITES

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Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 15 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 0

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Figure 3, REMP Sample Locations (Far Field)

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 16 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant

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Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 17 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 6.0 REPORTING LEVELS FOR RADIOACTIVITY CONCENTRATIONS IN ENVIRONMENTAL SAMPLES Table 6, Reporting Levels for Radioactivity Concentrations in Environmental Samples Air Particulates Fish (pCi/kg-Food Products Radionuclide Water (pCi/L) or Gases Milk (pCi/L)

(pCi/m3) wet)

(pCi/Kg-wet)

H-3 20,000 1 NA NA NA NA Mn-54 1,000 NA 30,000 NA NA Fe-59 400 NA 10,000 NA NA Co-58 1,000 NA 30,000 NA NA Co-60 300 NA 10,000 NA NA Zn-65 300 NA 20,000 NA NA Zr-Nb-95 400 NA NA NA NA 1-131 22 0.9 NA 3

100 Cs-134 30 10 1,000 60 1,000 Cs-137 50 20 2,000 70 2,000 Ba-La-140 200 NA NA 300 NA Table 7, Minimum Detectable Concentration (MDC)

Water Air Particulates Fish Milk Food Products Sediment Radionuclide (pCi/L) or Gases (pCi/kg-(pCi/L)

(pCi/Kg-wet)

(pCi/Kg-dry)

(pCi/m3) wet)

Gross Beta 4

0.01 NA NA NA NA H-3 2,0003 NA NA NA NA NA Mn-54 15 NA 130 NA NA NA Fe-59 30 NA 260 NA NA NA Co-58, Co-60 15 NA 130 NA NA NA Zn-65 30 NA 260 NA NA NA Zr-Nb-95 15 NA NA NA NA NA 1-131 14 0.07 NA 1

60 NA Cs-134 15 0.05 130 15 60 150 Cs-137 18 0.06 150 18 80 180 Ba-La-140 15 NA NA 15 NA NA 1 For drinking water samples: If no drinking water pathway exists, a value of 30,000 pCi/L may be used.

2 If no drinking water pathway exists, a value of 20 pCi/I may be used 3 If no drinking water pathway exists, a value of 3,000 pCi/L may be used. Some states may require a lower LLD for drinking water sources-per 40CFR141 Safe drinking water ACT.

4 If no drinking water pathway exists, a value of 15 pCi/I may be used

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 18 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 7.0 SAMPLING PROGRAM, PROGRAM MODIFICATION AND INTERPRETATION OF RESULTS At most nuclear stations, data was collected prior to plant operation to determine background radioactivity levels in the environment. Annual data is routinely compared to preoperational and/or 10-year average values to determine if changes in the environment are present. Strict comparison is difficult to make due to fallout from historical nuclear weapon testing. Cesium-137 can be routinely found in environmental samples as a results of above ground nuclear weapons testing. It is important to note, levels of Cs-137 in environment are observed to fluctuate, for example as silt distributions shift due to natural erosion and transport processes, Cs-137 may or may not be observed in sediment samples. Results from samples collected and analyzed during the year, 2024, are described below.

In the following sections, results from direct radiation, air, water, and food products analyzed as part of REMP in 2024 will be discussed. Sampling program descriptions and deviations will also be discussed.

In addition to the discussion of the results in the following sections, a summary of the results for 2024 is presented in Attachment 1, Data Table Summary. The analysis results for each of the samples collected is included in Attachment 2, Complete Data Table for All Analysis Results Obtained in 2024, and Attachment 4, Environmental Direct Radiation Dosimetry Sample Results. Attachment 3 contains the Cross Check lntercomparison Program which is mandatory for laboratories performing analyses of REMP samples satisfying the requirements in the Offsite Site Dose Calculation Manual.

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 19 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 7.1 Environmental Direct Radiation Dosimetry Sample Results Dose is measured as net exposure (field reading less transit reading) normalized to 91-day quarters. Data is treated and analyzed consistent with ANSI/HPS N13.37-2014, which compares the measured dose for each location to the baseline background dose for that location. Environmental dose rates vary by location, depending on geological and land use considerations, and remain relatively constant for any given location (unless land use changes). Some facilities observe seasonal variation in environmental doses. Baseline Background Doses have been determined for both quarterly and annual measurements at each location using historical field measurements. Minimum Differential Doses for Annual and Quarterly periods have been determined based on 3-times the 90th percentile standard deviation for monitoring locations. Doses that exceed the Minimum Differential Dose value above the Baseline Background Dose are considered to indicate Facility-Related Dose; a quality assurance review is performed to verify that any results indicating Facility-Related Dose are accurate.

ANSI/HPS N13.37-2014 uses the concept of minimum differential dose (MOD), which is the minimum facility-related dose that can be detected above the baseline background. Due to natural background variations and measurement sensitivities and uncertainties, the minimum differential dose is not zero. MOD is calculated based on performance of the dosimetry system in the environment and is about 5 mrem per quarter and 10 mrem per year. If a dosimeter indicates that a dose is greater than background plus the MOD value, then the net dose (above background) is reported as Facility Related Dose. If a dosimeter reports a dose less than background plus MOD, then the net dose is reported as non-detect (ND).

Direct (external) radiation at Plant Hatch is measured with Optically Stimulated Luminescent dosimeters (OSLO) by placing two OSLO badges at each station. The gamma dose at each station was reported as the average reading of the two badges.

The badges were analyzed on a quarterly basis.

Two direct radiation stations were established in each of the 16 compass sectors, to form two concentric rings. The inner ring (Stations 101 through 116) was located near the plant perimeter as shown in Figure 2 and the outer ring (Stations 201 through 216) was located at distances of four to five miles from the plant as shown in Figure

3. The stations in the East sector were a few additional miles away with regards to the other stations in their respective rings due to large swamps making normal access extremely difficult. The 16 stations forming the inner ring were designated as the indicator stations. The two-ring configuration of stations was established in accordance with NRC Branch Technical Position "An Acceptable Radiological Environmental Monitoring Program", Revision 1, November 1979. The three control stations (Nos. 304, 309 and 416) were located at distances greater than 10 miles from the plant as shown in Figure 2. Other outer ring stations listed in Table 5 including stations 201 through 216, as well as stations 064 and 301, monitor special interest areas. Station 064 was located at the onsite roadside park, while Station 301 was located near the Toombs Central School. Station 210, in the outer ring, was located near the Altamaha School (the only other nearby school).

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 20 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant In 2024, SNC implemented American National Standards Institute (ANSI) N13.37-2014 Environmental Dosimetry - Criteria for System Design and Implementation for comparing each OSLO location dose result to its historical background dose.

During this calendar year 2024, a total of 146 samples were collected and analyzed in accordance with the requirements in Table 1, Radiological Environmental Sampling Program - Exposure Pathway - Direct Radiation. Attachment 4, Environmental Direct Radiation Dosimetry Sample Results, includes the annual direct radiation dosimetry sample results.

7.1.1 Quarterly Facility Dose All the quarterly "inner ring" and "outer ring" indicator locations resulted in non-detectable (ND) dose. All the quarterly offsite "special interest" and control locations resulted in ND dose. The average quarterly normalized dose for the Indicator, Control, Outer Ring, and the Special Interest (Roadside Park and Toombs Central School) were all between 15 and 16 mrem per standard quarter.

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Toombs Central School (Station 301)

Figure 5, Average Quarterly Dose from Direct Radiation in Select Locations

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 21 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 7.1.2 Calculated Annual Facility Dose All the annual "inner ring" and "outer ring" indicator locations resulted in non-detectable (ND) dose. All the annual "special interest" and control locations resulted in ND dose.

7.1.3 OSLO Deviations and Anomalies There were 4 instances of direct radiation sample deviations during the reporting period. A description of these deviations can be found in Section 9.0, Sample Deviations, Anomalies, and Unavailability.

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 22 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 7.2 Air Particulate and Radioiodine Sample Results Air particulate filters and charcoal canisters were collected from locations specified in Table 2, Radiological Environmental Sampling Program -

Exposure Pathway -

Airborne. During this calendar year 2024, a total of 564 samples were collected and analyzed for gross beta, gamma emitters and iodine. Particulate samplers are used to analyze for gross beta activity following filter change out which occurs weekly. Gamma isotopic analysis is performed on composite samples collected at each location and is analyzed quarterly. Radioiodine (1-131) analysis is performed weekly on radioiodine sample cartridges.

1. Gamma Spectroscopy Gamma spectroscopy was conducted on each of the quarterly particulate composite samples. Throughout 2024, no radionuclides were detected in the gamma isotopic analysis of the quarterly composites from the air particulate filters, except for Be-7. Be-7 is a naturally occurring isotope and was not released from plant operations. Be-7 was detected in 22 of 24 samples. Concentrations at the indicator stations ranged from <MDC to 1696 fCi/m 3, with an average of 17 4.1 fCi/m 3. Control station concentrations ranged from 49.7 to 105.1 fCi/m 3, with an average of 66.9 fCi/m 3.

2. Gross Beta Gross beta activity was detected in all 282 samples. Indicator location samples had concentrations ranging from 4.8 to 41.5 fCi/m 3 with an average concentration of 19 fCi/m 3. Control location samples had concentrations ranging from 4.8 to 40 fCi/m3 with an average of 19.3 fCi/m 3. Gross beta activity was less than ten times the yearly mean of control samples. Therefore, per the ODCM gamma isotopic analysis was not required to be performed on the individual samples.

3. 1-131 1-131 was not detected in the air cartridges at either the indicator or control stations in 2024. Historically, 1-131 has been detected because of offsite events (i.e.,

Chernobyl).

Refer to Figure 6: Air Particulate: Analysis for Gross Beta, Average Mean for All Indicator Vs. Control, for air particulate/ radioiodine sample trends.

Air particulate and radioiodine results from this monitoring period, 2024, were compared to or 10-year averages as shown in Figure 6, and there were no material changes.

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 23 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 30

-;;,21 E

~ 24 -

C 0

+-' 21 re L.

+-'

C QJ U 18 C

0 u 15 2014 Air Particulate: Analysis for Gross Beta 2016 2018 Year

-+-Indicator 2020 2022 2024

-+-Control Figure 6: Air Particulate: Analysis for Gross Beta, Average Mean for All Indicator Vs. Control

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 24 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 7.3 Waterborne Sample Results 7.3.1 Surface Water (River Water)

~

u c..

+-'

u

<(

E

J f-Composite water samples are collected monthly at the upstream control location and at the downstream indicator location. Monthly composite samples are analyzed for gamma emitters. Aliquots from the monthly composites are combined to form a quarterly composites which is then analyzed for tritium. During this calendar year 2024, a total of 30 river water samples were collected and analyzed in accordance with the requirements in the ODCM and shown in Table 3, Radiological Environmental Sampling Program - Exposure Pathway - Waterborne.

1. Gamma Spectroscopy As provided in Attachment 1, no plant related gamma emitters were detected above the MDC in any of the indicator or control surface water samples.

2. Tritium Tritium had no detectible measurements in all samples. These historical values represent background conditions for tritium in drinking water and were not attributable to plant activity. Also, note that negative values in radionuclide activity represent contamination factors (e.g. laboratory equipment) subtracted from the laboratory result.

River Water Tritium Data 300 250 200 150 100 50 0

2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024

-e-lndicator -e-control Figure 7: Surface Water Tritium Results

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 25 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 7.3.2 Sediment from Shoreline Shoreline sediment collections were collected in April and October of 2024 and analyzed for gamma-emitting isotopes. Along with indicator locations samples are also collected at the control locations. A total of 4 shoreline samples were analyzed in accordance with requirements in the ODCM and shown in Table 3, Radiological Environmental Sampling Program - Exposure Pathway - Waterborne.

A gamma isotopic analysis was performed on each sample. There were no reportable radionuclides detected in sediment samples in 2024.

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 26 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 7.4 Ingestion Pathway Sample Results 7.4.1 Milk Milk samples were collected bi-weekly from Station 304 (the state prison dairy) which was a control station located more than 10 miles from the plant. Since 1989, efforts to locate a reliable milk sample source within five miles of the plant have been unsuccessful and the 2024 land census did not identify a milk animal within five miles of the plant.

Gamma isotopic (including 1-131 and Cs-137) analyses were performed on all 27 collected milk samples, and there were no detectable results for gamma isotopes.

7.4.2 Fish A total of 13 fish samples were collected in 2024. These samples were analyzed for gamma emitting radionuclides in edible portions, in accordance with requirements of the ODCM and summarized in Table 4, Radiological Environmental Sampling Program

- Exposure Pathway - Ingestion. These samples are collected from the indicator and control areas as required by the ODCM.

For the semi-annual collections, the control location (170) was located upriver of the plant intake structure, and the indicator location (172) was located downriver of the plant discharge structure. As shown in Attachment 1, in 2024, there were no man-made gamma isotopes detected in HNP REMP fish samples, except for Cs-137, which was detected in 1 indicator sample. The indicator station concentration for Cs-137 had a range of <MDC to 16.6 pCi/kg-wet, with an average of 2.4 pCi/kg-wet. No other gamma nuclides were detected in 2024.

7.4.3 Grass and Leafy Vegetation In accordance with the ODCM and as described in Table 4, Radiological Environmental Sampling Program - Exposure Pathway - Ingestion, 34 broad leaf vegetation samples were collected from growing locations nearest site boundary in areas of highest predicted annual average ground level D/Q. Samples are collected and analyzed for gamma isotopic and 1-131 from the indicator and control locations monthly during growing season. It is common to detect Cs-137 in broadleaf samples at both indicator and control locations. Cs-137 can be attributed to offsite sources such as weapons testing, Chernobyl, and Fukushima events. While Cs-137 is periodically found in vegetation samples, the historical relationship between the indicator and control locations demonstrate that the plant is not the source of activity detected.

Be-7 was detected in all vegetation samples during 2024 but was not released in plant effluents throughout the year. The concentrations at the indicator stations ranged from 682 to 14,956 pCi/kg-wet, with an average concentration of 3,780.7 pCi/kg-wet, while the concentrations at the control stations ranged from 1,229.6 to 9,062.5 pCi/kg-wet, with an average of 3,268.8 pCi/kg-wet.

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 27 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant Cs-137 was detected in 10 of 34 samples during 2024, and all 10 samples were from indicator locations. Indicator station concentrations ranged from <MDC to 116.4 pCi/kg-wet, with an average of 29.9 pCi/kg-wet. The sample results were consistently well below the MDC and the RL for Cs-137 (80 and 2000 pCi/kg-wet, respectively).

During 2024, there were no other gamma isotopes detected in any vegetation samples.

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 28 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 8.0 LAND USE CENSUS EXPOSURE PATHWAY Annual Land Use Census required by the Offsite Dose Calculation Manual is performed to ensure that changes in the use of areas at or beyond the site boundary are identified and modifications to REMP are made if required by changes in land use. Land use census satisfies the requirements of Section IV.B.3 of Appendix I to 10 CFR 50 [2].

NUREG-1301/1302 Control 3.12.2 specifies that "a land use census shall be conducted and shall identify within a distance of 8 km (5 mi.) the location in each of the 16 meteorological sectors of the nearest milk animal, the nearest residence and the nearest garden of greater than 50 m2 (500 ft2) producing broad leaf vegetation." Note, per NUREG-1301 /1302, Broad leaf vegetation sampling of at least three different kinds of vegetation may be performed at the SITE BOUNDARY in each of two different direction sectors with the highest predicted D/Qs in lieu of the garden census.

A Land Use Census was conducted during the calendar year, 2024, within the growing season to identify changes in land use, receptor locations, and new exposure pathways. The results for the 2024 Land Use Census are listed in Table 8: Land Use Census - Nearest Residence within 5 miles. In summary, the highest D/Q locations for nearest garden, nearest residence and nearest milk animal did not change following the 2024 census.

Table 8, Land Use Census - Nearest Residence within 5 miles Nearest Nearest Nearest Residence Milk Nearest Beef Garden Direction Distance Animal Cattle Distance Distance (miles)

Distance (Miles)

(miles)

N 2.0 None None 3.8 NNE 2.9 None None None NE 3.3 None 4.7 3.1 ENE 4.2 None 4.1 None E

3.0 None None None ESE 3.8 None None None SE 1.8 None 2.4 None SSE 2.0 None None None s

1.0 None 2.5 1.0 SSW 1.3 None 2.1 None SW 1.1 None 2.6 None WSW 1.0 None 3.6 None w

1.1 None 2.7 None WNW 1.1 None None None NW 3.6 None 4.5 None NNW 1.8 None 2.8 2.9

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 29 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 9.0 SAMPLE DEVIATIONS, ANOMALIES AND UNAVAILABILITY Sampling and analysis are performed for media types addressed in the Offsite Dose Calculation Manual. Sampling and analysis challenges may be experienced due to a multitude of reasons including environmental factors, loss of OSLDs, contamination of samples etc. To aid classification of sampling and analysis challenges experienced in 2024, the following three terms are used to describe the issues: Sample Anomalies (SA), Sample Deviation (SD), and Unavailable Samples (US).

Media that experienced downtime (i.e., air samplers or water samplers) during a surveillance period are classified a "Sample Deviation". "Sample Anomalies" are defined as errors that were introduced to a sample once it arrived in the laboratory, errors that prevents the sample from being analyzed as it normally would, or may have altered the outcome of the analysis (i.e., cross contamination, human error). "Sample Unavailability" is defined as sample collection with no available sample (i.e., food crop, OSLO).

All required samples were collected and analyzed as scheduled except for the following:

a e '

T bl 9 S I D ampe ev1at1on s ummary Sample Collection Reason for not conducting Plans for preventing Type and Location Date or REMP sampling as required Analysis Period byODCM reoccurrence Airborne HNP 01, 03, 04 Loss of power/ Loss of power to Power line surveyed and Sample Location 107 2024 sample station due to weather power restored.

Deviation conditions.

Airborne HNP 02, 04 Loss of power/ Loss of power to Power line surveyed and Sample Location 112 2024 sample station due to weather power restored.

Deviation conditions.

Airborne HNP Loss of power to sample station Power line surveyed and Sample 04 2024 Deviation Location 103 due to weather conditions.

power restored.

Airborne HNP Loss of power to sample station Power line surveyed and Sample 04 2024 Deviation Location 304 due to weather conditions.

power restored.

Direct OSLO location inaccessible due Radiation HNP 04 2024 to river level at time of sample River level monitored for next Sample Location 104 collection. OSLO collected 3 routine sample event Deviation days later than scheduled.

Sediment HNP Samples spilled during Procedure updated to specify Sample Locations 04 2024 Anomaly 170/172 shipping.

sample container type.

Direct OSLO was found on the ground OSLO sample location Radiation HNP near the original sample temporarily moved to nearby Sample Location 111 04 2024 location due to timber removal utility sign. A new permanent Deviation operations at the site.

station location is being investiqated.

Direct HNP Radiation Locations 04 2024 OSLO missing due to utility pole OSLDs replaced.

Sample 203, 101 replacement Deviation Note: Q4 deviations attributed to weather conditions are weather-related impacts stemming from Hurricane Helene.

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 30 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 10.0 OTHER SUPPLEMENTAL INFORMATION 10.1 NEI 07-07 Onsite Radiological Groundwater Monitoring Program Hatch Nuclear Plant has developed a Groundwater Protection Initiative (GPI) program in accordance with NEI 07-07, Industry Ground Water Protection Initiative -

Final Guidance Document. The purpose of the GPI is to ensure timely detection and an effective response to situations involving inadvertent radiological releases to groundwater to prevent migration of licensed radioactive material off-site and to quantify impacts on decommissioning. It is important to note, samples and results taken in support of NEI 07-07 groundwater monitoring program are not part of the Radiological Environmental Monitoring Program (REMP). Results of NEI 07-07 Radiological Groundwater Monitoring Program for onsite samples are included in the ARERR.

10.2 Corrections to Previous Reports No errata/corrections to previous reports identified.

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 31 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant 11.0 Bibliography

[1] NCRP, "Report No. 160, Ionizing Radiation Exposure of the Population of the United States,"

National Council on Radiation Protection, Bethesda, 2009.

[2] "10 CFR 50, "Domestic Licensing of Production and Utilization Facilities"," US Nuclear Regulatory Commission, Washington, DC.

[3] "Regulatory Guide 4.1, "Radiological Environmental Monitoring for Nuclear Power Plants",

Revision 2," Nuclear Regulatory Commission, 2009.

[4] "NUREG-1301, "Offsite Dose Calculation Manual Guidance: Standard Radiological Effluent Controls for Pressurized Water Reactors,".," Nuclear Regulatory Commission, April 1991.

[5] "NUREG-1302, "Offsite Dose Calculation Manual Guidance: Standard Radiological Effluent Controls for Boiling Water Reactors,"," Nuclear Regulatory Commission, April 1991.

[6] "Branch Technical Position, Revision 1," NRC000096, Submitted March 30, 2012, November 1979.

[7] "Japan Atomic Energy Agency," 06 November 2020. [Online]. Available:

https://www.jaea.go.jp/english/04/ntokai/houkan/houkan_02.html.

[8] "Regulatory Guide 4.15, Quality Assurance for Radiological Monitoring Programs (Inception through Normal Operations to License Termination) -- Effluent Streams and the Environment,"

Nuclear Regulatory Commission, July, 2007.

[9] "Regulatory Guide 4.13, Performance, Testing, and Procedural Specifications for Thermoluminescence Dosimetry: Environmental Applications, Revision 2," Nuclear Regulatory Commision, June, 2019.

[1 O] "NUREG/CR-2919, "XOQDOQ Computer Program for the Meteorological Evaluation of Routine Effluent Releases at Nuclear Power Stations,"," Nuclear Regulatory Commission, September, 1982.

[11] "Measurements of Radionuclides in the environment Sampling and Analysis of plutonium in soil,"

Nuclear Regulatory Commission, 197 4.

[12] "Ionizing Radiation Exposure of the Population of the United States," Bethesda, MD, 2009.

[13] Nuclear Regulatory Commission, 30 June 2015. [Online]. Available: http://www.nrc.gov/reading-rm/basic-ref/students/animated-pwr.html. [Accessed October 2020].

[14] "ICRP Publication 60, "ICRP Publication 60: 1990 Recommendations of the International Commission on Radiological Protection, 60," Annals of the ICRP Volume 21/1-3,," International Commission on Radiation Protection, October, 1991.

[15] "NRC Resource Page," [Online]. Available: http://www.nrc.gov/about-nrc/radiation.html. [Accessed 10 November 2020].

[16] "NUREG-0133, Preparation of Effluent Technical Specifications for Nuclear Power Plants,"

Nuclear Regulatory Commission, 1987.

[17] "Regulatory Guide 1.109, "Calculation of Annual Doses to Man from Routine Releases of Reactor Effluents for the Purpose of Demonstrating Compliance with 10 CFR Part 50, Appendix I,,"

Nuclear Regulatory Commission, Ocotober, 1977.

[18] [Online]. Available: http://hps.org/hpspublications/radiationfactsheets.html. [Accessed 2020].

[19] "NEI 07-07, "Industry Ground Water Protection Initiative-Final Guidance Document,"," Nuclear Energy Institute, Washington, D.C..

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 32 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant

[20] "ANSI 13.37, Environmental Dosimetry-Criteria for System Design and Implementation," Health Physics Society (HPS), May, 2019.

[21] "40 CFR Part 141, "National Primary Drinking Water Regulations,"," US Environmental Protection Agency, Washington, DC..

[22] Nuclear Regulatory Commission, 25 June 2015. [Online]. Available: http://www.nrc.gov/reading-rm/basic-ref/students/animated-bwr.html. [Accessed October 2020].

[23] "NEI 07-07, "Industry Ground Water Protection Initiative-Final Guidance Document," Rev. 1,"

Nuclear Energy Institute, Washington, D.C., 2019.

[24] Nuclear Regulatory Commission, 25 June 2015. [Online]. Available: http://www.nrc.gov/reading-rm/basic-ref/students/animated-bwr.html. [Accessed October 2020].

[25] [Online]. Available: http://hps.org/hpspublications/radiationfactsheets.html. [Accessed 2020].

[26] "Japan Atomic Energy Agency," 06 November 2020. [Online]. Available:

https://www.jaea.go.jp/english/04/ntokai/houkan/houkan_02.html.

[27] "NRC Resource Page," [Online]. Available: http://www.nrc.gov/about-nrc/radiation.html. [Accessed 10 November 2020].

[28] "NUREG-0133, Preparation of Effluent Technical Specifications for Nuclear Power Plants,"

Nuclear Regulatory Commission, 1987.

[29] Nuclear Regulatory Commission, 30 June 2015. [Online]. Available: http://www.nrc.gov/reading-rm/basic-ref/students/animated-pwr.html. [Accessed October 2020].

[30] "Regulatory Guide 4.13, Performance, Testing, and Procedural Specifications for Thermoluminescence Dosimetry: Environmental Applications, Revision 2," Nuclear Regulatory Commision, June, 2019.

[31] "Regulatory Guide 4.15, Quality Assurance for Radiological Monitoring Programs (Inception through Normal Operations to License Termination) -- Effluent Streams and the Environment,"

Nuclear Regulatory Commission, July, 2007.

[32] "10 CFR 50 - Domestic Licensing of Production and Utilization Facilities," US Nuclear Regulatory Commission, Washington, DC.

[33] "40 CFR 190 - Environmental Radiation Protection Standards for Nuclear Power Operation," US Environmental Protection Agency, Washington, DC.

[34] "NUREG-0324 - XOQDOQ, Program for the Meteorological Evaluation of Routine Effluent Releases at Nuclear Power Stations," Nuclear Regulatory Commission, September, 1977.

[35] "NCRP Report No. 160 - Ionizing Radiation Exposure of the Population of the United States,"

National Council on Radiation Protection and Measurements, Bethesda, MD, 2009.

[36] "Regulatory Guide 1.109 - Calculation of Annual Doses to Man from Routine Releases of Reactor Effluents for the Purpose of Demonstrating Compliance with 10 CFR Part 50, Appendix I," Nuclear Regulatory Commission, Ocotober, 1977.

[37] "40 CFR 141 - National Primary Drinking Water Regulations," US Environmental Protection Agency, Washington, DC..

[38] "10 CFR 20 - Standards for Protection Against Radiation," US Nuclear Regulatory Commission, Washington, DC.

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 33 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Data Table Summary

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 34 of 91 Company: Southern Nuclear I Plant:

Hatch Nuclear Plant, Data Table Summary Type, Total Lower Location with Highest Annual Mean Other Medium or Number of Limit of Indicator Mean Name Mean Control Mean Locations Pathway Sampled Analyses (f)

(f)

(Units) performed Detection Rangeb,c Distance and (f)

Rangeb,c Mean (f).

(e.g., 1-131, 400)

(LLD)3 Direction Rangeb Rangeb,c Gross Beta, 282 10 19 (176/176)

Inner Ring NNW 1.6 19.6 (53/53) 19.3 (106/106) 4.8-41.5 mi.

5.3-36.1 4.8-40 Gamma Isotopic, 24 Air Particulates Be-7 NA 174.1 (14/16)

Inner Ring WSW 1 481.6 (4/4) 66.9 (8/8)

(fCi/m3) 0-1696 mi.

62-1696 49.7-105.1 1-131 70 NDM NDM Cs-134 50 NDM NDM Cs-137 60 NDM NDM Airborne Radioiodine 1-131, 282 70 NDM NDM (fCi/m3)

Direct Radiation Gamma Dose, 144 NA 16.1 (62/62)

Inner Ring NW 1.1 21.0(4/4) 16.1 (12/12) 16 (70/70)

(mR/Qtr.)

12.4-23.3 mi.

19.8-23.3 12.4-17.9 11.2-21.4 Low Level 1-131, 27 1

NDM Gamma Isotopic, 27 Cs-134 15 NDM NDM Milk (pCi/L)

Cs-137 18 NDM NDM Ba-140 60 NDM NDM La-140 15 NDM NDM Gamma Isotopic, 34 Be-7 NA 3780.7 (23/23)

Inner Ring ESE 1.1 5373 (11/11) 3268.8 (11/11) 682-14956 mi.

1400.6-14956 1229.6-9062.5 Vegetation (pCi/kg-1-131 60 NDM NDM wet)

Cs-134 60 NDM NDM Cs-137 80 29.9 (10/23)

Inner Ring ESE 1.1 58.5 (9/11)

NDM 0-116.4 mi.

0-116.4 Surface Water -

Gamma Isotopic, 22 Be-7 NA NDM NDM River Water Mn-54 15 NDM NDM (pCi/L)

Fe-59 30 NDM NDM

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 35 of 91 Company: Southern Nuclear I Plant:

Hatch Nuclear Plant, Data Table Summary Type, Total Lower Location with Highest Annual Mean Other Medium or Number of Limit of Indicator Mean Name Mean Control Mean Locations Pathway Sampled Analyses (f)

(f)

(Units) performed Detection Rangeb,c Distance and (f)

Rangeb,c Mean (f).

(e.g., 1-131, 400)

(LLD)3 Direction Rangeb Rangeb,c Co-58 15 NDM NDM Co-60 15 NDM NDM Zn-65 30 NDM NDM Zr-95 30 NDM NDM Nb-95 15 NDM NDM 1-131 d 15 NDM NDM Cs-134 15 NDM NDM Cs-137 18 NDM NDM Ba-140 60 NDM NDM La-140 15 NDM NDM Tritiume, 8 3000 NDM NDM Gamma Isotopic, 13 Be-7 NA NDM NDM Mn-54 130 NDM NDM Fe-59 260 NDM NDM Co-58 130 NDM NDM Fish (pCi/kg-wet)

Co-60 130 NDM NDM Zn-65 260 NDM NDM Cs-134 130 NDM NDM Cs-137 2.4(1/7)

Downstream E ~ 3.0 2.4(1/7) 150 0-16.6 RM from intake 0-16.6 NDM Gamma Isotopic, 4 Sediment (pCi/kg-Be-7 NA NDM NDM dry)

Cs-134 150 NDM NDM Cs-137 180 NDM NDM

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 36 of 91 Company: Southern Nuclear I Plant:

Hatch Nuclear Plant, Data Table Summary Type, Total Lower Location with Highest Annual Mean Other Medium or Number of Limit of Indicator Mean Name Mean Control Mean Locations Pathway Sampled Analyses (f)

(f)

(Units) performed Detection Rangeb,c Distance and (f)

Rangeb,c Mean (f).

(e.g., 1-131, 400)

(LLD)3 Direction Rangeb Rangeb,c Notes:

a.

Except as noted otherwise, the values listed in this column are the detection capabilities required by Table 7, which are defined in the ODCM. The values listed in this column are a priori (before the fact) MDCs. In practice, the a posteriori (after the fact) MDCs are generally lower than the values listed.

b.

Mean and range were based upon detectable measurements only. The fraction of all measurements at a specified location that are detectable is placed in parenthesis.

c.

No Detectable Measurement(s) (NDM)

d.

If a drinking water pathway were to exist, an MDC of 1 pCi/L would have been used.

e.

If a drinking water pathway were to exist, an MDC of 2000 pCi/L would have been used.

f.

Not Applicable (NA)

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 37 of 91 Company: Southern Nuclear I Plant:

Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024, Complete Data Table for All Analysis Results Obtained In 2024

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 38 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Air Filters 103 1/2/2024 Gross Beta 0.0213 0.0034 0.0241 pCi/m3 Air Filters 103 1/8/2024 Gross Beta 0.0249 0.0040 0.0282 pCi/m3 Air Filters 103 1/15/2024 Gross Beta 0.0224 0.0035 0.0254 pCi/m3 Air Filters 103 1/22/2024 Gross Beta 0.0234 0.0035 0.0264 pCi/m3 Air Filters 103 1/29/2024 Gross Beta 0.0051 0.0025 0.0072 pCi/m3 Air Filters 103 2/6/2024 Gross Beta 0.0169 0.0032 0.0195 pCi/m3 Air Filters 103 2/13/2024 Gross Beta 0.0103 0.0026 0.0124 pCi/m3 Air Filters 103 2/19/2024 Gross Beta 0.0239 0.0039 0.0272 pCi/m3 Air Filters 103 2/26/2024 Gross Beta 0.0215 0.0035 0.0244 pCi/m3 Air Filters 103 3/4/2024 Gross Beta 0.0189 0.0033 0.0217 pCi/m3 Air Filters 103 3/11/2024 Gross Beta 0.0081 0.0028 0.0105 pCi/m3 Air Filters 103 3/18/2024 Gross Beta 0.0195 0.0033 0.0223 pCi/m3 Air Filters 103 3/25/2024 Gross Beta 0.0169 0.0032 0.0196 pCi/m3 Air Filters 103 4/1/2024 Gross Beta 0.0196 0.0035 0.0225 pCi/m3 Air Filters 103 4/8/2024 Gross Beta 0.0152 0.0032 0.0179 pCi/m3 Air Filters 103 4/16/2024 Gross Beta 0.0155 0.0032 0.0182 pCi/m3 Air Filters 103 4/22/2024 Gross Beta 0.0203 0.0034 0.0232 pCi/m3 Air Filters 103 4/29/2024 Gross Beta 0.0235 0.0036 0.0265 pCi/m3 Air Filters 103 5/6/2024 Gross Beta 0.0141 0.0032 0.0168 pCi/m3 Air Filters 103 5/13/2024 Gross Beta 0.0149 0.0032 0.0176 pCi/m3 Air Filters 103 5/21/2024 Gross Beta 0.0150 0.0027 0.0173 pCi/m3 Air Filters 103 5/28/2024 Gross Beta 0.0130 0.0031 0.0156 pCi/m3 Air Filters 103 6/3/2024 Gross Beta 0.0213 0.0037 0.0244 pCi/m3 Air Filters 103 6/10/2024 Gross Beta 0.0217 0.0036 0.0248 pCi/m3 Air Filters 103 6/17/2024 Gross Beta 0.0203 0.0034 0.0232 pCi/m3 Air Filters 103 6/24/2024 Gross Beta 0.0125 0.0030 0.0151 pCi/m3 Air Filters 103 7/1/2024 Gross Beta 0.0151 0.0031 0.0177 pCi/m3 Air Filters 103 7/8/2024 Gross Beta 0.0098 0.0030 0.0123 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 39 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Air Filters 103 7/15/2024 Gross Beta 0.0182 0.0033 0.0209 pCi/m3 Air Filters 103 7/22/2024 Gross Beta 0.0075 0.0028 0.0099 pCi/m3 Air Filters 103 7/29/2024 Gross Beta 0.0141 0.0030 0.0166 pCi/m3 Air Filters 103 8/6/2024 Gross Beta 0.0109 0.0025 0.0130 pCi/m3 Air Filters 103 8/12/2024 Gross Beta 0.0286 0.0042 0.0321 pCi/m3 Air Filters 103 8/19/2024 Gross Beta 0.0313 0.0040 0.0346 pCi/m3 Air Filters 103 8/26/2024 Gross Beta 0.0216 0.0036 0.0247 pCi/m3 Air Filters 103 9/3/2024 Gross Beta 0.0117 0.0026 0.0139 pCi/m3 Air Filters 103 9/9/2024 Gross Beta 0.0152 0.0035 0.0181 pCi/m3 Air Filters 103 9/16/2024 Gross Beta 0.0208 0.0035 0.0237 pCi/m3 Air Filters 103 9/23/2024 Gross Beta 0.0217 0.0036 0.0247 pCi/m3 Air Filters 103 10/1/2024 Gross Beta 0.0281 0.0062 0.0333 pCi/m3 Air Filters 103 10/21/2024 Gross Beta 0.0197 0.0051 0.0239 pCi/m3 Air Filters 103 10/28/2024 Gross Beta 0.0390 0.0042 0.0426 pCi/m3 Air Filters 103 11/4/2024 Gross Beta 0.0220 0.0035 0.0250 pCi/m3 Air Filters 103 11/11/2024 Gross Beta 0.0138 0.0029 0.0163 pCi/m3 Air Filters 103 11/18/2024 Gross Beta 0.0265 0.0037 0.0297 pCi/m3 Air Filters 103 11/25/2024 Gross Beta 0.0224 0.0033 0.0252 pCi/m3 Air Filters 103 12/2/2024 Gross Beta 0.0233 0.0035 0.0263 pCi/m3 Air Filters 103 12/9/2024 Gross Beta 0.0333 0.0039 0.0367 pCi/m3 Air Filters 103 12/16/2024 Gross Beta 0.0232 0.0035 0.0261 pCi/m3 Air Filters 103 12/23/2024 Gross Beta 0.0181 0.0033 0.0208 pCi/m3 Air Filters 103 12/30/2024 Gross Beta 0.0184 0.0033 0.0212 pCi/m3 Air Filters 107 1/8/2024 Gross Beta 0.0299 0.0045 0.0337 pCi/m3 Air Filters 107 1/15/2024 Gross Beta 0.0229 0.0038 0.0260 pCi/m3 Air Filters 107 1/22/2024 Gross Beta 0.0269 0.0039 0.0301 pCi/m3 Air Filters 107 1/29/2024 Gross Beta 0.0048 0.0026 0.0070 pCi/m3 Air Filters 107 2/6/2024 Gross Beta 0.0205 0.0036 0.0235 pCi/m3 Air Filters 107 2/13/2024 Gross Beta 0.0082 0.0026 0.0104 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 40 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Air Filters 107 2/19/2024 Gross Beta 0.0271 0.0052 0.0315 pCi/m3 Air Filters 107 4/16/2024 Gross Beta 0.0168 0.0042 0.0203 pCi/m3 Air Filters 107 4/22/2024 Gross Beta 0.0206 0.0035 0.0235 pCi/m3 Air Filters 107 4/29/2024 Gross Beta 0.0171 0.0034 0.0200 pCi/m3 Air Filters 107 5/6/2024 Gross Beta 0.0115 0.0031 0.0141 pCi/m3 Air Filters 107 5/13/2024 Gross Beta 0.0131 0.0032 0.0158 pCi/m3 Air Filters 107 5/21/2024 Gross Beta 0.0154 0.0028 0.0178 pCi/m3 Air Filters 107 5/28/2024 Gross Beta 0.0133 0.0032 0.0159 pCi/m3 Air Filters 107 6/3/2024 Gross Beta 0.0205 0.0038 0.0237 pCi/m3 Air Filters 107 6/10/2024 Gross Beta 0.0200 0.0036 0.0230 pCi/m3 Air Filters 107 6/17/2024 Gross Beta 0.0233 0.0037 0.0265 pCi/m3 Air Filters 107 6/24/2024 Gross Beta 0.0139 0.0032 0.0166 pCi/m3 Air Filters 107 7/1/2024 Gross Beta 0.0152 0.0032 0.0179 pCi/m3 Air Filters 107 7/8/2024 Gross Beta 0.0101 0.0031 0.0127 pCi/m3 Air Filters 107 7/15/2024 Gross Beta 0.0150 0.0033 0.0178 pCi/m3 Air Filters 107 7/22/2024 Gross Beta 0.0126 0.0032 0.0152 pCi/m3 Air Filters 107 7/29/2024 Gross Beta 0.0159 0.0031 0.0186 pCi/m3 Air Filters 107 8/6/2024 Gross Beta 0.0125 0.0027 0.0147 pCi/m3 Air Filters 107 8/12/2024 Gross Beta 0.0305 0.0044 0.0342 pCi/m3 Air Filters 107 8/19/2024 Gross Beta 0.0265 0.0038 0.0297 pCi/m3 Air Filters 107 8/26/2024 Gross Beta 0.0236 0.0055 0.0282 pCi/m3 Air Filters 107 9/9/2024 Gross Beta 0.0147 0.0035 0.0177 pCi/m3 Air Filters 107 9/16/2024 Gross Beta 0.0170 0.0034 0.0199 pCi/m3 Air Filters 107 9/23/2024 Gross Beta 0.0207 0.0037 0.0238 pCi/m3 Air Filters 107 10/1/2024 Gross Beta 0.0280 0.0063 0.0333 pCi/m3 Air Filters 107 12/30/2024 Gross Beta 0.0215 0.0019 0.0231 pCi/m3 Air Filters 112 1/2/2024 Gross Beta 0.0271 0.0037 0.0302 pCi/m3 Air Filters 112 1/8/2024 Gross Beta 0.0268 0.0041 0.0302 pCi/m3 Air Filters 112 1/15/2024 Gross Beta 0.0231 0.0036 0.0261 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 41 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Air Filters 112 1/22/2024 Gross Beta 0.0246 0.0036 0.0276 pCi/m3 Air Filters 112 1/29/2024 Gross Beta 0.0071 0.0026 0.0093 pCi/m3 Air Filters 112 2/6/2024 Gross Beta 0.0167 0.0032 0.0194 pCi/m3 Air Filters 112 2/13/2024 Gross Beta 0.0108 0.0026 0.0130 pCi/m3 Air Filters 112 2/19/2024 Gross Beta 0.0195 0.0037 0.0225 pCi/m3 Air Filters 112 2/26/2024 Gross Beta 0.0236 0.0035 0.0266 pCi/m3 Air Filters 112 3/4/2024 Gross Beta 0.0153 0.0032 0.0180 pCi/m3 Air Filters 112 3/11/2024 Gross Beta 0.0102 0.0030 0.0127 pCi/m3 Air Filters 112 3/18/2024 Gross Beta 0.0190 0.0033 0.0218 pCi/m3 Air Filters 112 3/25/2024 Gross Beta 0.0207 0.0035 0.0236 pCi/m3 Air Filters 112 4/1/2024 Gross Beta 0.0168 0.0033 0.0196 pCi/m3 Air Filters 112 4/8/2024 Gross Beta 0.0147 0.0032 0.0174 pCi/m3 Air Filters 112 4/16/2024 Gross Beta 0.0165 0.0033 0.0193 pCi/m3 Air Filters 112 4/22/2024 Gross Beta 0.0220 0.0036 0.0249 pCi/m3 Air Filters 112 4/29/2024 Gross Beta 0.0232 0.0036 0.0262 pCi/m3 Air Filters 112 5/6/2024 Gross Beta 0.0144 0.0032 0.0171 pCi/m3 Air Filters 112 5/13/2024 Gross Beta 0.0181 0.0035 0.0210 pCi/m3 Air Filters 112 5/21/2024 Gross Beta 0.0207 0.0043 0.0244 pCi/m3 Air Filters 112 5/28/2024 Gross Beta 0.0132 0.0041 0.0167 pCi/m3 Air Filters 112 6/3/2024 Gross Beta 0.0269 0.0041 0.0303 pCi/m3 Air Filters 112 6/10/2024 Gross Beta 0.0231 0.0037 0.0262 pCi/m3 Air Filters 112 6/17/2024 Gross Beta 0.0252 0.0038 0.0283 pCi/m3 Air Filters 112 6/24/2024 Gross Beta 0.0121 0.0031 0.0147 pCi/m3 Air Filters 112 7/1/2024 Gross Beta 0.0157 0.0032 0.0184 pCi/m3 Air Filters 112 7/8/2024 Gross Beta 0.0108 0.0031 0.0134 pCi/m3 Air Filters 112 7/15/2024 Gross Beta 0.0209 0.0035 0.0238 pCi/m3 Air Filters 112 7/22/2024 Gross Beta 0.0123 0.0031 0.0149 pCi/m3 Air Filters 112 7/29/2024 Gross Beta 0.0140 0.0030 0.0165 pCi/m3 Air Filters 112 8/6/2024 Gross Beta 0.0105 0.0025 0.0127 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 42 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Air Filters 112 8/12/2024 Gross Beta 0.0305 0.0044 0.0342 pCi/m3 Air Filters 112 8/19/2024 Gross Beta 0.0293 0.0039 0.0325 pCi/m3 Air Filters 112 8/26/2024 Gross Beta 0.0183 0.0036 0.0213 pCi/m3 Air Filters 112 9/3/2024 Gross Beta 0.0130 0.0027 0.0153 pCi/m3 Air Filters 112 9/9/2024 Gross Beta 0.0162 0.0036 0.0192 pCi/m3 Air Filters 112 9/16/2024 Gross Beta 0.0183 0.0034 0.0211 pCi/m3 Air Filters 112 9/23/2024 Gross Beta 0.0221 0.0037 0.0252 pCi/m3 Air Filters 112 10/1/2024 Gross Beta 0.0317 0.0065 0.0371 pCi/m3 Air Filters 116 1/2/2024 Gross Beta 0.0261 0.0038 0.0293 pCi/m3 Air Filters 116 1/8/2024 Gross Beta 0.0249 0.0042 0.0284 pCi/m3 Air Filters 116 1/15/2024 Gross Beta 0.0223 0.0037 0.0255 pCi/m3 Air Filters 116 1/22/2024 Gross Beta 0.0215 0.0036 0.0245 pCi/m3 Air Filters 116 1/29/2024 Gross Beta 0.0053 0.0027 0.0075 pCi/m3 Air Filters 116 2/6/2024 Gross Beta 0.0191 0.0034 0.0220 pCi/m3 Air Filters 116 2/13/2024 Gross Beta 0.0096 0.0027 0.0118 pCi/m3 Air Filters 116 2/19/2024 Gross Beta 0.0180 0.0037 0.0211 pCi/m3 Air Filters 116 2/26/2024 Gross Beta 0.0215 0.0036 0.0245 pCi/m3 Air Filters 116 3/4/2024 Gross Beta 0.0179 0.0034 0.0208 pCi/m3 Air Filters 116 3/11/2024 Gross Beta 0.0088 0.0030 0.0114 pCi/m3 Air Filters 116 3/18/2024 Gross Beta 0.0189 0.0035 0.0218 pCi/m3 Air Filters 116 3/25/2024 Gross Beta 0.0208 0.0036 0.0238 pCi/m3 Air Filters 116 4/1/2024 Gross Beta 0.0188 0.0036 0.0219 pCi/m3 Air Filters 116 4/8/2024 Gross Beta 0.0174 0.0035 0.0203 pCi/m3 Air Filters 116 4/16/2024 Gross Beta 0.0124 0.0029 0.0148 pCi/m3 Air Filters 116 4/22/2024 Gross Beta 0.0212 0.0035 0.0241 pCi/m3 Air Filters 116 4/29/2024 Gross Beta 0.0206 0.0036 0.0236 pCi/m3 Air Filters 116 5/6/2024 Gross Beta 0.0121 0.0031 0.0148 pCi/m3 Air Filters 116 5/13/2024 Gross Beta 0.0122 0.0032 0.0149 pCi/m3 Air Filters 116 5/21/2024 Gross Beta 0.0130 0.0027 0.0152 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 43 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Air Filters 116 5/28/2024 Gross Beta 0.0127 0.0032 0.0154 pCi/m3 Air Filters 116 6/3/2024 Gross Beta 0.0245 0.0040 0.0278 pCi/m3 Air Filters 116 6/10/2024 Gross Beta 0.0192 0.0036 0.0222 pCi/m3 Air Filters 116 6/17/2024 Gross Beta 0.0193 0.0035 0.0222 pCi/m3 Air Filters 116 6/24/2024 Gross Beta 0.0113 0.0031 0.0139 pCi/m3 Air Filters 116 7/1/2024 Gross Beta 0.0114 0.0030 0.0139 pCi/m3 Air Filters 116 7/8/2024 Gross Beta 0.0082 0.0030 0.0107 pCi/m3 Air Filters 116 7/15/2024 Gross Beta 0.0180 0.0034 0.0208 pCi/m3 Air Filters 116 7/22/2024 Gross Beta 0.0112 0.0032 0.0139 pCi/m3 Air Filters 116 7/29/2024 Gross Beta 0.0118 0.0028 0.0141 pCi/m3 Air Filters 116 8/6/2024 Gross Beta 0.0107 0.0026 0.0129 pCi/m3 Air Filters 116 8/12/2024 Gross Beta 0.0277 0.0043 0.0313 pCi/m3 Air Filters 116 8/19/2024 Gross Beta 0.0302 0.0040 0.0336 pCi/m3 Air Filters 116 8/26/2024 Gross Beta 0.0216 0.0036 0.0247 pCi/m3 Air Filters 116 9/3/2024 Gross Beta 0.0133 0.0028 0.0156 pCi/m3 Air Filters 116 9/9/2024 Gross Beta 0.0112 0.0034 0.0140 pCi/m3 Air Filters 116 9/16/2024 Gross Beta 0.0195 0.0035 0.0224 pCi/m3 Air Filters 116 9/23/2024 Gross Beta 0.0223 0.0038 0.0255 pCi/m3 Air Filters 116 10/1/2024 Gross Beta 0.0349 0.0059 0.0398 pCi/m3 Air Filters 116 10/7/2024 Gross Beta 0.0257 0.0041 0.0292 pCi/m3 Air Filters 116 10/15/2024 Gross Beta 0.0378 0.0044 0.0415 pCi/m3 Air Filters 116 10/21/2024 Gross Beta 0.0219 0.0038 0.0251 pCi/m3 Air Filters 116 10/28/2024 Gross Beta 0.0415 0.0046 0.0453 pCi/m3 Air Filters 116 11/4/2024 Gross Beta 0.0221 0.0038 0.0253 pCi/m3 Air Filters 116 11/11/2024 Gross Beta 0.0133 0.0031 0.0160 pCi/m3 Air Filters 116 11/18/2024 Gross Beta 0.0276 0.0041 0.0310 pCi/m3 Air Filters 116 11/25/2024 Gross Beta 0.0249 0.0037 0.0280 pCi/m3 Air Filters 116 12/2/2024 Gross Beta 0.0268 0.0039 0.0301 pCi/m3 Air Filters 116 12/9/2024 Gross Beta 0.0379 0.0047 0.0419 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 44 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Air Filters 116 12/16/2024 Gross Beta 0.0230 0.0037 0.0260 pCi/m3 Air Filters 116 12/23/2024 Gross Beta 0.0145 0.0033 0.0173 pCi/m3 Air Filters 116 12/30/2024 Gross Beta 0.0210 0.0037 0.0240 pCi/m3 Air Filters 304 1/2/2024 Gross Beta 0.0260 0.0038 0.0292 pCi/m3 Air Filters 304 1/8/2024 Gross Beta 0.0241 0.0041 0.0276 pCi/m3 Air Filters 304 1/15/2024 Gross Beta 0.0210 0.0036 0.0240 pCi/m3 Air Filters 304 1/22/2024 Gross Beta 0.0255 0.0038 0.0286 pCi/m3 Air Filters 304 1/29/2024 Gross Beta 0.0051 0.0025 0.0072 pCi/m3 Air Filters 304 2/6/2024 Gross Beta 0.0188 0.0034 0.0217 pCi/m3 Air Filters 304 2/13/2024 Gross Beta 0.0101 0.0030 0.0126 pCi/m3 Air Filters 304 2/19/2024 Gross Beta 0.0228 0.0040 0.0261 pCi/m3 Air Filters 304 2/26/2024 Gross Beta 0.0225 0.0037 0.0256 pCi/m3 Air Filters 304 3/4/2024 Gross Beta 0.0183 0.0034 0.0212 pCi/m3 Air Filters 304 3/11/2024 Gross Beta 0.0093 0.0031 0.0119 pCi/m3 Air Filters 304 3/18/2024 Gross Beta 0.0201 0.0035 0.0231 pCi/m3 Air Filters 304 3/25/2024 Gross Beta 0.0188 0.0035 0.0218 pCi/m3 Air Filters 304 4/1/2024 Gross Beta 0.0196 0.0037 0.0226 pCi/m3 Air Filters 304 4/8/2024 Gross Beta 0.0166 0.0034 0.0195 pCi/m3 Air Filters 304 4/16/2024 Gross Beta 0.0154 0.0033 0.0181 pCi/m3 Air Filters 304 4/22/2024 Gross Beta 0.0218 0.0036 0.0249 pCi/m3 Air Filters 304 4/29/2024 Gross Beta 0.0225 0.0037 0.0256 pCi/m3 Air Filters 304 5/6/2024 Gross Beta 0.0120 0.0031 0.0147 pCi/m3 Air Filters 304 5/13/2024 Gross Beta 0.0123 0.0032 0.0150 pCi/m3 Air Filters 304 5/21/2024 Gross Beta 0.0130 0.0028 0.0154 pCi/m3 Air Filters 304 5/28/2024 Gross Beta 0.0132 0.0031 0.0158 pCi/m3 Air Filters 304 6/3/2024 Gross Beta 0.0241 0.0040 0.0275 pCi/m3 Air Filters 304 6/10/2024 Gross Beta 0.0204 0.0037 0.0234 pCi/m3 Air Filters 304 6/17/2024 Gross Beta 0.0230 0.0037 0.0261 pCi/m3 Air Filters 304 6/24/2024 Gross Beta 0.0113 0.0030 0.0138 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 45 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Air Filters 304 7/1/2024 Gross Beta 0.0128 0.0031 0.0154 pCi/m3 Air Filters 304 7/8/2024 Gross Beta 0.0092 0.0031 0.0118 pCi/m3 Air Filters 304 7/15/2024 Gross Beta 0.0193 0.0035 0.0222 pCi/m3 Air Filters 304 7/22/2024 Gross Beta 0.0107 0.0031 0.0133 pCi/m3 Air Filters 304 7/29/2024 Gross Beta 0.0131 0.0030 0.0156 pCi/m3 Air Filters 304 8/6/2024 Gross Beta 0.0117 0.0026 0.0139 pCi/m3 Air Filters 304 8/12/2024 Gross Beta 0.0324 0.0045 0.0362 pCi/m3 Air Filters 304 8/19/2024 Gross Beta 0.0259 0.0038 0.0291 pCi/m3 Air Filters 304 8/26/2024 Gross Beta 0.0205 0.0037 0.0236 pCi/m3 Air Filters 304 9/3/2024 Gross Beta 0.0107 0.0026 0.0129 pCi/m3 Air Filters 304 9/9/2024 Gross Beta 0.0129 0.0035 0.0158 pCi/m3 Air Filters 304 9/16/2024 Gross Beta 0.0180 0.0034 0.0209 pCi/m3 Air Filters 304 9/23/2024 Gross Beta 0.0202 0.0037 0.0233 pCi/m3 Air Filters 304 10/1/2024 Gross Beta 0.0314 0.0067 0.0370 pCi/m3 Air Filters 304 10/7/2024 Gross Beta 0.0268 0.0069 0.0327 pCi/m3 Air Filters 304 10/15/2024 Gross Beta 0.0352 0.0043 0.0388 pCi/m3 Air Filters 304 10/21/2024 Gross Beta 0.0224 0.0037 0.0256 pCi/m3 Air Filters 304 10/28/2024 Gross Beta 0.0400 0.0045 0.0437 pCi/m3 Air Filters 304 11/4/2024 Gross Beta 0.0192 0.0035 0.0222 pCi/m3 Air Filters 304 11/11/2024 Gross Beta 0.0117 0.0029 0.0141 pCi/m3 Air Filters 304 11/18/2024 Gross Beta 0.0222 0.0037 0.0253 pCi/m3 Air Filters 304 11/25/2024 Gross Beta 0.0246 0.0036 0.0276 pCi/m3 Air Filters 304 12/2/2024 Gross Beta 0.0260 0.0038 0.0292 pCi/m3 Air Filters 304 12/9/2024 Gross Beta 0.0324 0.0041 0.0358 pCi/m3 Air Filters 304 12/16/2024 Gross Beta 0.0222 0.0036 0.0252 pCi/m3 Air Filters 304 12/23/2024 Gross Beta 0.0145 0.0033 0.0173 pCi/m3 Air Filters 304 12/30/2024 Gross Beta 0.0181 0.0034 0.0210 pCi/m3 Air Filters 309 1/2/2024 Gross Beta 0.0218 0.0036 0.0248 pCi/m3 Air Filters 309 1/8/2024 Gross Beta 0.0254 0.0042 0.0289 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 46 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Air Filters 309 1/15/2024 Gross Beta 0.0223 0.0037 0.0254 pCi/m3 Air Filters 309 1/22/2024 Gross Beta 0.0230 0.0037 0.0261 pCi/m3 Air Filters 309 1/29/2024 Gross Beta 0.0048 0.0026 0.0070 pCi/m3 Air Filters 309 2/6/2024 Gross Beta 0.0177 0.0034 0.0206 pCi/m3 Air Filters 309 2/13/2024 Gross Beta 0.0077 0.0025 0.0098 pCi/m3 Air Filters 309 2/19/2024 Gross Beta 0.0228 0.0040 0.0262 pCi/m3 Air Filters 309 2/26/2024 Gross Beta 0.0224 0.0037 0.0255 pCi/m3 Air Filters 309 3/4/2024 Gross Beta 0.0175 0.0034 0.0203 pCi/m3 Air Filters 309 3/11/2024 Gross Beta 0.0062 0.0029 0.0087 pCi/m3 Air Filters 309 3/18/2024 Gross Beta 0.0170 0.0033 0.0198 pCi/m3 Air Filters 309 3/25/2024 Gross Beta 0.0177 0.0035 0.0206 pCi/m3 Air Filters 309 4/1/2024 Gross Beta 0.0175 0.0035 0.0204 pCi/m3 Air Filters 309 4/8/2024 Gross Beta 0.0166 0.0034 0.0195 pCi/m3 Air Filters 309 4/16/2024 Gross Beta 0.0169 0.0033 0.0197 pCi/m3 Air Filters 309 4/22/2024 Gross Beta 0.0221 0.0036 0.0252 pCi/m3 Air Filters 309 4/29/2024 Gross Beta 0.0231 0.0037 0.0263 pCi/m3 Air Filters 309 5/6/2024 Gross Beta 0.0102 0.0030 0.0127 pCi/m3 Air Filters 309 5/13/2024 Gross Beta 0.0158 0.0034 0.0187 pCi/m3 Air Filters 309 5/21/2024 Gross Beta 0.0141 0.0028 0.0165 pCi/m3 Air Filters 309 5/28/2024 Gross Beta 0.0116 0.0030 0.0141 pCi/m3 Air Filters 309 6/3/2024 Gross Beta 0.0215 0.0039 0.0248 pCi/m3 Air Filters 309 6/10/2024 Gross Beta 0.0214 0.0037 0.0245 pCi/m3 Air Filters 309 6/17/2024 Gross Beta 0.0195 0.0035 0.0225 pCi/m3 Air Filters 309 6/24/2024 Gross Beta 0.0138 0.0032 0.0165 pCi/m3 Air Filters 309 7/1/2024 Gross Beta 0.0165 0.0034 0.0194 pCi/m3 Air Filters 309 7/8/2024 Gross Beta 0.0103 0.0031 0.0130 pCi/m3 Air Filters 309 7/15/2024 Gross Beta 0.0187 0.0035 0.0217 pCi/m3 Air Filters 309 7/22/2024 Gross Beta 0.0081 0.0029 0.0106 pCi/m3 Air Filters 309 7/29/2024 Gross Beta 0.0139 0.0030 0.0164 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 47 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Air Filters 309 8/6/2024 Gross Beta 0.0118 0.0027 0.0140 pCi/m3 Air Filters 309 8/12/2024 Gross Beta 0.0279 0.0043 0.0315 pCi/m3 Air Filters 309 8/19/2024 Gross Beta 0.0293 0.0039 0.0326 pCi/m3 Air Filters 309 8/26/2024 Gross Beta 0.0203 0.0037 0.0235 pCi/m3 Air Filters 309 9/3/2024 Gross Beta 0.0125 0.0027 0.0148 pCi/m3 Air Filters 309 9/9/2024 Gross Beta 0.0147 0.0036 0.0178 pCi/m3 Air Filters 309 9/16/2024 Gross Beta 0.0186 0.0035 0.0215 pCi/m3 Air Filters 309 9/23/2024 Gross Beta 0.0223 0.0038 0.0255 pCi/m3 Air Filters 309 10/1/2024 Gross Beta 0.0349 0.0045 0.0386 pCi/m3 Air Filters 309 10/7/2024 Gross Beta 0.0231 0.0041 0.0265 pCi/m3 Air Filters 309 10/15/2024 Gross Beta 0.0305 0.0037 0.0336 pCi/m3 Air Filters 309 10/21/2024 Gross Beta 0.0228 0.0039 0.0261 pCi/m3 Air Filters 309 10/28/2024 Gross Beta 0.0361 0.0042 0.0397 pCi/m3 Air Filters 309 11/4/2024 Gross Beta 0.0192 0.0036 0.0222 pCi/m3 Air Filters 309 11/11/2024 Gross Beta 0.0149 0.0032 0.0176 pCi/m3 Air Filters 309 11/18/2024 Gross Beta 0.0214 0.0035 0.0244 pCi/m3 Air Filters 309 11/25/2024 Gross Beta 0.0230 0.0036 0.0260 pCi/m3 Air Filters 309 12/2/2024 Gross Beta 0.0262 0.0038 0.0295 pCi/m3 Air Filters 309 12/9/2024 Gross Beta 0.0324 0.0041 0.0358 pCi/m3 Air Filters 309 12/16/2024 Gross Beta 0.0228 0.0036 0.0258 pCi/m3 Air Filters 309 12/23/2024 Gross Beta 0.0161 0.0033 0.0189 pCi/m3 Air Filters 309 12/30/2024 Gross Beta 0.0210 0.0035 0.0240 pCi/m3 Air Qtr Comp 103 3/25/2024 Cs-134 0.0000 0.0000 0.0012 pCi/m3 Air Qtr Comp 103 3/25/2024 Cs-137 0.0000 0.0000 0.0012 pCi/m3 Air Qtr Comp 103 3/25/2024 Be-7 0.0553 0.0198 0.0000 pCi/m3 Air Qtr Comp 103 3/25/2024 1-131 0.0000 0.0000 0.0053 pCi/m3 Air Qtr Comp 103 6/24/2024 1-131 0.0000 0.0000 0.0099 pCi/m3 Air Qtr Comp 103 6/24/2024 Be-7 0.0773 0.0349 0.0000 pCi/m3 Air Qtr Comp 103 6/24/2024 Cs-134 0.0000 0.0000 0.0027 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 48 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Air Qtr Comp 103 6/24/2024 Cs-137 0.0000 0.0000 0.0019 pCi/m3 Air Qtr Comp 103 9/23/2024 1-131 0.0000 0.0000 0.0136 pCi/m3 Air Qtr Comp 103 9/23/2024 Cs-134 0.0000 0.0000 0.0011 pCi/m3 Air Qtr Comp 103 9/23/2024 Cs-137 0.0000 0.0000 0.0010 pCi/m3 Air Qtr Comp 103 9/23/2024 Be-7 0.0780 0.0217 0.0000 pCi/m3 Air Qtr Comp 103 12/30/2024 Cs-137 0.0000 0.0000 0.0012 pCi/m3 Air Qtr Comp 103 12/30/2024 1-131 0.0000 0.0000 0.0226 pCi/m3 Air Qtr Comp 103 12/30/2024 Cs-134 0.0000 0.0000 0.0012 pCi/m3 Air Qtr Comp 103 12/30/2024 Be-7 0.0489 0.0191 0.0000 pCi/m3 Air Qtr Comp 107 2/19/2024 Cs-134 0.0000 0.0000 0.0023 pCi/m3 Air Qtr Comp 107 2/19/2024 Cs-137 0.0000 0.0000 0.0026 pCi/m3 Air Qtr Comp 107 2/19/2024 1-131 0.0000 0.0000 0.3427 pCi/m3 Air Qtr Comp 107 2/19/2024 Be-7 0.0000 0.0000 0.0340 pCi/m3 Air Qtr Comp 107 6/24/2024 Be-7 0.0833 0.0240 0.0000 pCi/m3 Air Qtr Comp 107 6/24/2024 1-131 0.0000 0.0000 0.0047 pCi/m3 Air Qtr Comp 107 6/24/2024 Cs-137 0.0000 0.0000 0.0016 pCi/m3 Air Qtr Comp 107 6/24/2024 Cs-134 0.0000 0.0000 0.0013 pCi/m3 Air Qtr Comp 107 9/23/2024 1-131 0.0000 0.0000 0.0119 pCi/m3 Air Qtr Comp 107 9/23/2024 Be-7 0.0754 0.0239 0.0000 pCi/m3 Air Qtr Comp 107 9/23/2024 Cs-137 0.0000 0.0000 0.0011 pCi/m3 Air Qtr Comp 107 9/23/2024 Cs-134 0.0000 0.0000 0.0009 pCi/m3 Air Qtr Comp 107 12/30/2024 1-131 0.0000 0.0000 0.0362 pCi/m3 Air Qtr Comp 107 12/30/2024 Be-7 0.0000 0.0000 0.0259 pCi/m3 Air Qtr Comp 107 12/30/2024 Cs-134 0.0000 0.0000 0.0013 pCi/m3 Air Qtr Comp 107 12/30/2024 Cs-137 0.0000 0.0000 0.0018 pCi/m3 Air Qtr Comp 112 3/25/2024 Cs-134 0.0000 0.0000 0.0010 pCi/m3 Air Qtr Comp 112 3/25/2024 Be-7 0.0620 0.0200 0.0000 pCi/m3 Air Qtr Comp 112 3/25/2024 1-131 0.0000 0.0000 0.0054 pCi/m3 Air Qtr Comp 112 3/25/2024 Cs-137 0.0000 0.0000 0.0017 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 49 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Air Qtr Comp 112 6/24/2024 Cs-134 0.0000 0.0000 0.0026 pCi/m3 Air Qtr Comp 112 6/24/2024 Cs-137 0.0000 0.0000 0.0021 pCi/m3 Air Qtr Comp 112 6/24/2024 1-131 0.0000 0.0000 0.0092 pCi/m3 Air Qtr Comp 112 6/24/2024 Be-7 0.1052 0.0418 0.0000 pCi/m3 Air Qtr Comp 112 9/23/2024 1-131 0.0000 0.0000 0.0466 pCi/m3 Air Qtr Comp 112 9/23/2024 Be-7 0.0632 0.0302 0.0000 pCi/m3 Air Qtr Comp 112 9/23/2024 Cs-137 0.0000 0.0000 0.0019 pCi/m3 Air Qtr Comp 112 9/23/2024 Cs-134 0.0000 0.0000 0.0021 pCi/m3 Air Qtr Comp 112 10/1/2024 Be-7 1.6960 0.2921 0.0000 pCi/m3 Air Qtr Comp 112 10/1/2024 Cs-137 0.0000 0.0000 0.0127 pCi/m3 Air Qtr Comp 112 10/1/2024 1-131 0.0000 0.0000 0.2348 pCi/m3 Air Qtr Comp 112 10/1/2024 Cs-134 0.0000 0.0000 0.0120 pCi/m3 Air Qtr Comp 116 3/25/2024 Cs-134 0.0000 0.0000 0.0012 pCi/m3 Air Qtr Comp 116 3/25/2024 Be-7 0.0674 0.0225 0.0000 pCi/m3 Air Qtr Comp 116 3/25/2024 1-131 0.0000 0.0000 0.0089 pCi/m3 Air Qtr Comp 116 3/25/2024 Cs-137 0.0000 0.0000 0.0014 pCi/m3 Air Qtr Comp 116 6/24/2024 Be-7 0.0768 0.0219 0.0000 pCi/m3 Air Qtr Comp 116 6/24/2024 Cs-134 0.0000 0.0000 0.0013 pCi/m3 Air Qtr Comp 116 6/24/2024 Cs-137 0.0000 0.0000 0.0014 pCi/m3 Air Qtr Comp 116 6/24/2024 1-131 0.0000 0.0000 0.0031 pCi/m3 Air Qtr Comp 116 9/23/2024 Cs-137 0.0000 0.0000 0.0013 pCi/m3 Air Qtr Comp 116 9/23/2024 1-131 0.0000 0.0000 0.0111 pCi/m3 Air Qtr Comp 116 9/23/2024 Be-7 0.0657 0.0220 0.0000 pCi/m3 Air Qtr Comp 116 9/23/2024 Cs-134 0.0000 0.0000 0.0011 pCi/m3 Air Qtr Comp 116 12/30/2024 1-131 0.0000 0.0000 0.0215 pCi/m3 Air Qtr Comp 116 12/30/2024 Cs-137 0.0000 0.0000 0.0013 pCi/m3 Air Qtr Comp 116 12/30/2024 Cs-134 0.0000 0.0000 0.0012 pCi/m3 Air Qtr Comp 116 12/30/2024 Be-7 0.0728 0.0236 0.0000 pCi/m3 Air Qtr Comp 304 3/25/2024 1-131 0.0000 0.0000 0.0080 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 50 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Air Qtr Comp 304 3/25/2024 Be-7 0.0497 0.0200 0.0000 pCi/m3 Air Qtr Comp 304 3/25/2024 Cs-134 0.0000 0.0000 0.0014 pCi/m3 Air Qtr Comp 304 3/25/2024 Cs-137 0.0000 0.0000 0.0014 pCi/m3 Air Qtr Comp 304 6/24/2024 Be-7 0.0712 0.0333 0.0000 pCi/m3 Air Qtr Comp 304 6/24/2024 Cs-134 0.0000 0.0000 0.0023 pCi/m3 Air Qtr Comp 304 6/24/2024 Cs-137 0.0000 0.0000 0.0020 pCi/m3 Air Qtr Comp 304 6/24/2024 1-131 0.0000 0.0000 0.0089 pCi/m3 Air Qtr Comp 304 9/23/2024 Be-7 0.0574 0.0186 0.0000 pCi/m3 Air Qtr Comp 304 9/23/2024 1-131 0.0000 0.0000 0.0110 pCi/m3 Air Qtr Comp 304 9/23/2024 Cs-137 0.0000 0.0000 0.0009 pCi/m3 Air Qtr Comp 304 9/23/2024 Cs-134 0.0000 0.0000 0.0007 pCi/m3 Air Qtr Comp 304 12/30/2024 Cs-137 0.0000 0.0000 0.0010 pCi/m3 Air Qtr Comp 304 12/30/2024 Be-7 0.0794 0.0212 0.0000 pCi/m3 Air Qtr Comp 304 12/30/2024 Cs-134 0.0000 0.0000 0.0008 pCi/m3 Air Qtr Comp 304 12/30/2024 1-131 0.0000 0.0000 0.0200 pCi/m3 Air Qtr Comp 309 3/25/2024 Cs-137 0.0000 0.0000 0.0015 pCi/m3 Air Qtr Comp 309 3/25/2024 1-131 0.0000 0.0000 0.0091 pCi/m3 Air Qtr Comp 309 3/25/2024 Be-7 0.0657 0.0227 0.0000 pCi/m3 Air Qtr Comp 309 3/25/2024 Cs-134 0.0000 0.0000 0.0011 pCi/m3 Air Qtr Comp 309 6/24/2024 Be-7 0.1051 0.0255 0.0000 pCi/m3 Air Qtr Comp 309 6/24/2024 1-131 0.0000 0.0000 0.0039 pCi/m3 Air Qtr Comp 309 6/24/2024 Cs-137 0.0000 0.0000 0.0014 pCi/m3 Air Qtr Comp 309 6/24/2024 Cs-134 0.0000 0.0000 0.0011 pCi/m3 Air Qtr Comp 309 9/23/2024 Be-7 0.0547 0.0207 0.0000 pCi/m3 Air Qtr Comp 309 9/23/2024 1-131 0.0000 0.0000 0.0134 pCi/m3 Air Qtr Comp 309 9/23/2024 Cs-137 0.0000 0.0000 0.0011 pCi/m3 Air Qtr Comp 309 9/23/2024 Cs-134 0.0000 0.0000 0.0011 pCi/m3 Air Qtr Comp 309 12/30/2024 Cs-137 0.0000 0.0000 0.0012 pCi/m3 Air Qtr Comp 309 12/30/2024 Be-7 0.0520 0.0187 0.0000 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 51 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Air Qtr Comp 309 12/30/2024 1-131 0.0000 0.0000 0.0232 pCi/m3 Air Qtr Comp 309 12/30/2024 Cs-134 0.0000 0.0000 0.0013 pCi/m3 Charcoal Ct 103 1/2/2024 1-131 0.0000 0.0000 0.0213 pCi/m3 Charcoal Ct 103 1/8/2024 1-131 0.0000 0.0000 0.0330 pCi/m3 Charcoal Ct 103 1/15/2024 1-131 0.0000 0.0000 0.0269 pCi/m3 Charcoal Ct 103 1/22/2024 1-131 0.0000 0.0000 0.0173 pCi/m3 Charcoal Ct 103 1/29/2024 1-131 0.0000 0.0000 0.0186 pCi/m3 Charcoal Ct 103 2/6/2024 1-131 0.0000 0.0000 0.0162 pCi/m3 Charcoal Ct 103 2/13/2024 1-131 0.0000 0.0000 0.0092 pCi/m3 Charcoal Ct 103 2/19/2024 1-131 0.0000 0.0000 0.0216 pCi/m3 Charcoal Ct 103 2/26/2024 1-131 0.0000 0.0000 0.0177 pCi/m3 Charcoal Ct 103 3/4/2024 1-131 0.0000 0.0000 0.0218 pCi/m3 Charcoal Ct 103 3/11/2024 1-131 0.0000 0.0000 0.0106 pCi/m3 Charcoal Ct 103 3/18/2024 1-131 0.0000 0.0000 0.0159 pCi/m3 Charcoal Ct 103 3/25/2024 1-131 0.0000 0.0000 0.0216 pCi/m3 Charcoal Ct 103 4/1/2024 1-131 0.0000 0.0000 0.0159 pCi/m3 Charcoal Ct 103 4/8/2024 1-131 0.0000 0.0000 0.0160 pCi/m3 Charcoal Ct 103 4/16/2024 1-131 0.0000 0.0000 0.0137 pCi/m3 Charcoal Ct 103 4/22/2024 1-131 0.0000 0.0000 0.0174 pCi/m3 Charcoal Ct 103 4/29/2024 1-131 0.0000 0.0000 0.0104 pCi/m3 Charcoal Ct 103 5/6/2024 1-131 0.0000 0.0000 0.0222 pCi/m3 Charcoal Ct 103 5/13/2024 1-131 0.0000 0.0000 0.0150 pCi/m3 Charcoal Ct 103 5/21/2024 1-131 0.0000 0.0000 0.0135 pCi/m3 Charcoal Ct 103 5/28/2024 1-131 0.0000 0.0000 0.0177 pCi/m3 Charcoal Ct 103 6/3/2024 1-131 0.0000 0.0000 0.0166 pCi/m3 Charcoal Ct 103 6/10/2024 1-131 0.0000 0.0000 0.0155 pCi/m3 Charcoal Ct 103 6/17/2024 1-131 0.0000 0.0000 0.0160 pCi/m3 Charcoal Ct 103 6/24/2024 1-131 0.0000 0.0000 0.0167 pCi/m3 Charcoal Ct 103 7/1/2024 1-131 0.0000 0.0000 0.0156 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 52 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Charcoal Ct 103 7/8/2024 1-131 0.0000 0.0000 0.0175 pCi/m3 Charcoal Ct 103 7/15/2024 1-131 0.0000 0.0000 0.0134 pCi/m3 Charcoal Ct 103 7/22/2024 1-131 0.0000 0.0000 0.0207 pCi/m3 Charcoal Ct 103 7/29/2024 1-131 0.0000 0.0000 0.0123 pCi/m3 Charcoal Ct 103 8/6/2024 1-131 0.0000 0.0000 0.0100 pCi/m3 Charcoal Ct 103 8/12/2024 1-131 0.0000 0.0000 0.0154 pCi/m3 Charcoal Ct 103 8/19/2024 1-131 0.0000 0.0000 0.0108 pCi/m3 Charcoal Ct 103 8/26/2024 1-131 0.0000 0.0000 0.0156 pCi/m3 Charcoal Ct 103 9/3/2024 1-131 0.0000 0.0000 0.0230 pCi/m3 Charcoal Ct 103 9/9/2024 1-131 0.0000 0.0000 0.0211 pCi/m3 Charcoal Ct 103 9/16/2024 1-131 0.0000 0.0000 0.0148 pCi/m3 Charcoal Ct 103 9/23/2024 1-131 0.0000 0.0000 0.0197 pCi/m3 Charcoal Ct 103 10/1/2024 1-131 0.0000 0.0000 0.0489 pCi/m3 Charcoal Ct 103 10/21/2024 1-131 0.0000 0.0000 0.0355 pCi/m3 Charcoal Ct 103 10/28/2024 1-131 0.0000 0.0000 0.0198 pCi/m3 Charcoal Ct 103 11/4/2024 1-131 0.0000 0.0000 0.0156 pCi/m3 Charcoal Ct 103 11/11/2024 1-131 0.0000 0.0000 0.0213 pCi/m3 Charcoal Ct 103 11/18/2024 1-131 0.0000 0.0000 0.0176 pCi/m3 Charcoal Ct 103 11/25/2024 1-131 0.0000 0.0000 0.0187 pCi/m3 Charcoal Ct 103 12/2/2024 1-131 0.0000 0.0000 0.0253 pCi/m3 Charcoal Ct 103 12/9/2024 1-131 0.0000 0.0000 0.0196 pCi/m3 Charcoal Ct 103 12/16/2024 1-131 0.0000 0.0000 0.0244 pCi/m3 Charcoal Ct 103 12/23/2024 1-131 0.0000 0.0000 0.0296 pCi/m3 Charcoal Ct 103 12/30/2024 1-131 0.0000 0.0000 0.0148 pCi/m3 Charcoal Ct 107 1/8/2024 1-131 0.0000 0.0000 0.0255 pCi/m3 Charcoal Ct 107 1/15/2024 1-131 0.0000 0.0000 0.0226 pCi/m3 Charcoal Ct 107 1/22/2024 1-131 0.0000 0.0000 0.0204 pCi/m3 Charcoal Ct 107 1/29/2024 1-131 0.0000 0.0000 0.0167 pCi/m3 Charcoal Ct 107 2/6/2024 1-131 0.0000 0.0000 0.0184 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 53 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Charcoal Ct 107 2/13/2024 1-131 0.0000 0.0000 0.0246 pCi/m3 Charcoal Ct 107 2/19/2024 1-131 0.0000 0.0000 0.0302 pCi/m3 Charcoal Ct 107 4/16/2024 1-131 0.0000 0.0000 0.0312 pCi/m3 Charcoal Ct 107 4/22/2024 1-131 0.0000 0.0000 0.0234 pCi/m3 Charcoal Ct 107 4/29/2024 1-131 0.0000 0.0000 0.0246 pCi/m3 Charcoal Ct 107 5/6/2024 1-131 0.0000 0.0000 0.0155 pCi/m3 Charcoal Ct 107 5/13/2024 1-131 0.0000 0.0000 0.0242 pCi/m3 Charcoal Ct 107 5/21/2024 1-131 0.0000 0.0000 0.0207 pCi/m3 Charcoal Ct 107 5/28/2024 1-131 0.0000 0.0000 0.0147 pCi/m3 Charcoal Ct 107 6/3/2024 1-131 0.0000 0.0000 0.0194 pCi/m3 Charcoal Ct 107 6/10/2024 1-131 0.0000 0.0000 0.0240 pCi/m3 Charcoal Ct 107 6/17/2024 1-131 0.0000 0.0000 0.0168 pCi/m3 Charcoal Ct 107 6/24/2024 1-131 0.0000 0.0000 0.0334 pCi/m3 Charcoal Ct 107 7/1/2024 1-131 0.0000 0.0000 0.0168 pCi/m3 Charcoal Ct 107 7/8/2024 1-131 0.0000 0.0000 0.0306 pCi/m3 Charcoal Ct 107 7/15/2024 1-131 0.0000 0.0000 0.0250 pCi/m3 Charcoal Ct 107 7/22/2024 1-131 0.0000 0.0000 0.0293 pCi/m3 Charcoal Ct 107 7/29/2024 1-131 0.0000 0.0000 0.0266 pCi/m3 Charcoal Ct 107 8/6/2024 1-131 0.0000 0.0000 0.0197 pCi/m3 Charcoal Ct 107 8/12/2024 1-131 0.0000 0.0000 0.0277 pCi/m3 Charcoal Ct 107 8/19/2024 1-131 0.0000 0.0000 0.0237 pCi/m3 Charcoal Ct 107 8/26/2024 1-131 0.0000 0.0000 0.0465 pCi/m3 Charcoal Ct 107 9/9/2024 1-131 0.0000 0.0000 0.0274 pCi/m3 Charcoal Ct 107 9/16/2024 1-131 0.0000 0.0000 0.0170 pCi/m3 Charcoal Ct 107 9/23/2024 1-131 0.0000 0.0000 0.0189 pCi/m3 Charcoal Ct 107 10/1/2024 1-131 0.0000 0.0000 0.0224 pCi/m3 Charcoal Ct 107 12/30/2024 1-131 0.0000 0.0000 0.0070 pCi/m3 Charcoal Ct 112 1/2/2024 1-131 0.0000 0.0000 0.0171 pCi/m3 Charcoal Ct 112 1/8/2024 1-131 0.0000 0.0000 0.0257 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 54 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Charcoal Ct 112 1/15/2024 1-131 0.0000 0.0000 0.0259 pCi/m3 Charcoal Ct 112 1/22/2024 1-131 0.0000 0.0000 0.0229 pCi/m3 Charcoal Ct 112 1/29/2024 1-131 0.0000 0.0000 0.0245 pCi/m3 Charcoal Ct 112 2/6/2024 1-131 0.0000 0.0000 0.0150 pCi/m3 Charcoal Ct 112 2/13/2024 1-131 0.0000 0.0000 0.0160 pCi/m3 Charcoal Ct 112 2/19/2024 1-131 0.0000 0.0000 0.0173 pCi/m3 Charcoal Ct 112 2/26/2024 1-131 0.0000 0.0000 0.0134 pCi/m3 Charcoal Ct 112 3/4/2024 1-131 0.0000 0.0000 0.0160 pCi/m3 Charcoal Ct 112 3/11/2024 1-131 0.0000 0.0000 0.0233 pCi/m3 Charcoal Ct 112 3/18/2024 1-131 0.0000 0.0000 0.0107 pCi/m3 Charcoal Ct 112 3/25/2024 1-131 0.0000 0.0000 0.0116 pCi/m3 Charcoal Ct 112 4/1/2024 1-131 0.0000 0.0000 0.0130 pCi/m3 Charcoal Ct 112 4/8/2024 1-131 0.0000 0.0000 0.0225 pCi/m3 Charcoal Ct 112 4/16/2024 1-131 0.0000 0.0000 0.0178 pCi/m3 Charcoal Ct 112 4/22/2024 1-131 0.0000 0.0000 0.0208 pCi/m3 Charcoal Ct 112 4/29/2024 1-131 0.0000 0.0000 0.0161 pCi/m3 Charcoal Ct 112 5/6/2024 1-131 0.0000 0.0000 0.0238 pCi/m3 Charcoal Ct 112 5/13/2024 1-131 0.0000 0.0000 0.0194 pCi/m3 Charcoal Ct 112 5/21/2024 1-131 0.0000 0.0000 0.0178 pCi/m3 Charcoal Ct 112 5/28/2024 1-131 0.0000 0.0000 0.0171 pCi/m3 Charcoal Ct 112 6/3/2024 1-131 0.0000 0.0000 0.0196 pCi/m3 Charcoal Ct 112 6/10/2024 1-131 0.0000 0.0000 0.0165 pCi/m3 Charcoal Ct 112 6/17/2024 1-131 0.0000 0.0000 0.0166 pCi/m3 Charcoal Ct 112 6/24/2024 1-131 0.0000 0.0000 0.0168 pCi/m3 Charcoal Ct 112 7/1/2024 1-131 0.0000 0.0000 0.0125 pCi/m3 Charcoal Ct 112 7/8/2024 1-131 0.0000 0.0000 0.0167 pCi/m3 Charcoal Ct 112 7/15/2024 1-131 0.0000 0.0000 0.0171 pCi/m3 Charcoal Ct 112 7/22/2024 1-131 0.0000 0.0000 0.0134 pCi/m3 Charcoal Ct 112 7/29/2024 1-131 0.0000 0.0000 0.0283 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 55 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Charcoal Ct 112 8/6/2024 1-131 0.0000 0.0000 0.0134 pCi/m3 Charcoal Ct 112 8/12/2024 1-131 0.0000 0.0000 0.0192 pCi/m3 Charcoal Ct 112 8/19/2024 1-131 0.0000 0.0000 0.0223 pCi/m3 Charcoal Ct 112 8/26/2024 1-131 0.0000 0.0000 0.0173 pCi/m3 Charcoal Ct 112 9/3/2024 1-131 0.0000 0.0000 0.0142 pCi/m3 Charcoal Ct 112 9/9/2024 1-131 0.0000 0.0000 0.0220 pCi/m3 Charcoal Ct 112 9/16/2024 1-131 0.0000 0.0000 0.0127 pCi/m3 Charcoal Ct 112 9/23/2024 1-131 0.0000 0.0000 0.0137 pCi/m3 Charcoal Ct 112 10/1/2024 1-131 0.0000 0.0000 0.0655 pCi/m3 Charcoal Ct 116 1/2/2024 1-131 0.0000 0.0000 0.0200 pCi/m3 Charcoal Ct 116 1/8/2024 1-131 0.0000 0.0000 0.0195 pCi/m3 Charcoal Ct 116 1/15/2024 1-131 0.0000 0.0000 0.0243 pCi/m3 Charcoal Ct 116 1/22/2024 1-131 0.0000 0.0000 0.0169 pCi/m3 Charcoal Ct 116 1/29/2024 1-131 0.0000 0.0000 0.0207 pCi/m3 Charcoal Ct 116 2/6/2024 1-131 0.0000 0.0000 0.0190 pCi/m3 Charcoal Ct 116 2/13/2024 1-131 0.0000 0.0000 0.0164 pCi/m3 Charcoal Ct 116 2/19/2024 1-131 0.0000 0.0000 0.0203 pCi/m3 Charcoal Ct 116 2/26/2024 1-131 0.0000 0.0000 0.0219 pCi/m3 Charcoal Ct 116 3/4/2024 1-131 0.0000 0.0000 0.0240 pCi/m3 Charcoal Ct 116 3/11/2024 1-131 0.0000 0.0000 0.0171 pCi/m3 Charcoal Ct 116 3/18/2024 1-131 0.0000 0.0000 0.0247 pCi/m3 Charcoal Ct 116 3/25/2024 1-131 0.0000 0.0000 0.0330 pCi/m3 Charcoal Ct 116 4/1/2024 1-131 0.0000 0.0000 0.0152 pCi/m3 Charcoal Ct 116 4/8/2024 1-131 0.0000 0.0000 0.0167 pCi/m3 Charcoal Ct 116 4/16/2024 1-131 0.0000 0.0000 0.0123 pCi/m3 Charcoal Ct 116 4/22/2024 1-131 0.0000 0.0000 0.0124 pCi/m3 Charcoal Ct 116 4/29/2024 1-131 0.0000 0.0000 0.0128 pCi/m3 Charcoal Ct 116 5/6/2024 1-131 0.0000 0.0000 0.0215 pCi/m3 Charcoal Ct 116 5/13/2024 1-131 0.0000 0.0000 0.0115 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 56 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Charcoal Ct 116 5/21/2024 1-131 0.0000 0.0000 0.0238 pCi/m3 Charcoal Ct 116 5/28/2024 1-131 0.0000 0.0000 0.0163 pCi/m3 Charcoal Ct 116 6/3/2024 1-131 0.0000 0.0000 0.0191 pCi/m3 Charcoal Ct 116 6/10/2024 1-131 0.0000 0.0000 0.0127 pCi/m3 Charcoal Ct 116 6/17/2024 1-131 0.0000 0.0000 0.0192 pCi/m3 Charcoal Ct 116 6/24/2024 1-131 0.0000 0.0000 0.0243 pCi/m3 Charcoal Ct 116 7/1/2024 1-131 0.0000 0.0000 0.0167 pCi/m3 Charcoal Ct 116 7/8/2024 1-131 0.0000 0.0000 0.0174 pCi/m3 Charcoal Ct 116 7/15/2024 1-131 0.0000 0.0000 0.0182 pCi/m3 Charcoal Ct 116 7/22/2024 1-131 0.0000 0.0000 0.0261 pCi/m3 Charcoal Ct 116 7/29/2024 1-131 0.0000 0.0000 0.0162 pCi/m3 Charcoal Ct 116 8/6/2024 1-131 0.0000 0.0000 0.0150 pCi/m3 Charcoal Ct 116 8/12/2024 1-131 0.0000 0.0000 0.0175 pCi/m3 Charcoal Ct 116 8/19/2024 1-131 0.0000 0.0000 0.0154 pCi/m3 Charcoal Ct 116 8/26/2024 1-131 0.0000 0.0000 0.0170 pCi/m3 Charcoal Ct 116 9/3/2024 1-131 0.0000 0.0000 0.0144 pCi/m3 Charcoal Ct 116 9/9/2024 1-131 0.0000 0.0000 0.0164 pCi/m3 Charcoal Ct 116 9/16/2024 1-131 0.0000 0.0000 0.0169 pCi/m3 Charcoal Ct 116 9/23/2024 1-131 0.0000 0.0000 0.0270 pCi/m3 Charcoal Ct 116 10/1/2024 1-131 0.0000 0.0000 0.0273 pCi/m3 Charcoal Ct 116 10/7/2024 1-131 0.0000 0.0000 0.0186 pCi/m3 Charcoal Ct 116 10/15/2024 1-131 0.0000 0.0000 0.0211 pCi/m3 Charcoal Ct 116 10/21/2024 1-131 0.0000 0.0000 0.0178 pCi/m3 Charcoal Ct 116 10/28/2024 1-131 0.0000 0.0000 0.0212 pCi/m3 Charcoal Ct 116 11/4/2024 1-131 0.0000 0.0000 0.0176 pCi/m3 Charcoal Ct 116 11/11/2024 1-131 0.0000 0.0000 0.0126 pCi/m3 Charcoal Ct 116 11/18/2024 1-131 0.0000 0.0000 0.0210 pCi/m3 Charcoal Ct 116 11/25/2024 1-131 0.0000 0.0000 0.0206 pCi/m3 Charcoal Ct 116 12/2/2024 1-131 0.0000 0.0000 0.0224 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 57 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Charcoal Ct 116 12/9/2024 1-131 0.0000 0.0000 0.0222 pCi/m3 Charcoal Ct 116 12/16/2024 1-131 0.0000 0.0000 0.0215 pCi/m3 Charcoal Ct 116 12/23/2024 1-131 0.0000 0.0000 0.0228 pCi/m3 Charcoal Ct 116 12/30/2024 1-131 0.0000 0.0000 0.0185 pCi/m3 Charcoal Ct 304 1/2/2024 1-131 0.0000 0.0000 0.0231 pCi/m3 Charcoal Ct 304 1/8/2024 1-131 0.0000 0.0000 0.0307 pCi/m3 Charcoal Ct 304 1/15/2024 1-131 0.0000 0.0000 0.0276 pCi/m3 Charcoal Ct 304 1/22/2024 1-131 0.0000 0.0000 0.0247 pCi/m3 Charcoal Ct 304 1/29/2024 1-131 0.0000 0.0000 0.0187 pCi/m3 Charcoal Ct 304 2/6/2024 1-131 0.0000 0.0000 0.0286 pCi/m3 Charcoal Ct 304 2/13/2024 1-131 0.0000 0.0000 0.0156 pCi/m3 Charcoal Ct 304 2/19/2024 1-131 0.0000 0.0000 0.0267 pCi/m3 Charcoal Ct 304 2/26/2024 1-131 0.0000 0.0000 0.0191 pCi/m3 Charcoal Ct 304 3/4/2024 1-131 0.0000 0.0000 0.0178 pCi/m3 Charcoal Ct 304 3/11/2024 1-131 0.0000 0.0000 0.0115 pCi/m3 Charcoal Ct 304 3/18/2024 1-131 0.0000 0.0000 0.0217 pCi/m3 Charcoal Ct 304 3/25/2024 1-131 0.0000 0.0000 0.0287 pCi/m3 Charcoal Ct 304 4/1/2024 1-131 0.0000 0.0000 0.0162 pCi/m3 Charcoal Ct 304 4/8/2024 1-131 0.0000 0.0000 0.0152 pCi/m3 Charcoal Ct 304 4/16/2024 1-131 0.0000 0.0000 0.0258 pCi/m3 Charcoal Ct 304 4/22/2024 1-131 0.0000 0.0000 0.0241 pCi/m3 Charcoal Ct 304 4/29/2024 1-131 0.0000 0.0000 0.0242 pCi/m3 Charcoal Ct 304 5/6/2024 1-131 0.0000 0.0000 0.0166 pCi/m3 Charcoal Ct 304 5/13/2024 1-131 0.0000 0.0000 0.0284 pCi/m3 Charcoal Ct 304 5/21/2024 1-131 0.0000 0.0000 0.0157 pCi/m3 Charcoal Ct 304 5/28/2024 1-131 0.0000 0.0000 0.0121 pCi/m3 Charcoal Ct 304 6/3/2024 1-131 0.0000 0.0000 0.0128 pCi/m3 Charcoal Ct 304 6/10/2024 1-131 0.0000 0.0000 0.0304 pCi/m3 Charcoal Ct 304 6/17/2024 1-131 0.0000 0.0000 0.0170 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 58 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Charcoal Ct 304 6/24/2024 1-131 0.0000 0.0000 0.0233 pCi/m3 Charcoal Ct 304 7/1/2024 1-131 0.0000 0.0000 0.0164 pCi/m3 Charcoal Ct 304 7/8/2024 1-131 0.0000 0.0000 0.0243 pCi/m3 Charcoal Ct 304 7/15/2024 1-131 0.0000 0.0000 0.0242 pCi/m3 Charcoal Ct 304 7/22/2024 1-131 0.0000 0.0000 0.0167 pCi/m3 Charcoal Ct 304 7/29/2024 1-131 0.0000 0.0000 0.0266 pCi/m3 Charcoal Ct 304 8/6/2024 1-131 0.0000 0.0000 0.0226 pCi/m3 Charcoal Ct 304 8/12/2024 1-131 0.0000 0.0000 0.0277 pCi/m3 Charcoal Ct 304 8/19/2024 1-131 0.0000 0.0000 0.0243 pCi/m3 Charcoal Ct 304 8/26/2024 1-131 0.0000 0.0000 0.0165 pCi/m3 Charcoal Ct 304 9/3/2024 1-131 0.0000 0.0000 0.0242 pCi/m3 Charcoal Ct 304 9/9/2024 1-131 0.0000 0.0000 0.0281 pCi/m3 Charcoal Ct 304 9/16/2024 1-131 0.0000 0.0000 0.0144 pCi/m3 Charcoal Ct 304 9/23/2024 1-131 0.0000 0.0000 0.0285 pCi/m3 Charcoal Ct 304 10/1/2024 1-131 0.0000 0.0000 0.0451 pCi/m3 Charcoal Ct 304 10/7/2024 1-131 0.0000 0.0000 0.0577 pCi/m3 Charcoal Ct 304 10/15/2024 1-131 0.0000 0.0000 0.0256 pCi/m3 Charcoal Ct 304 10/21/2024 1-131 0.0000 0.0000 0.0277 pCi/m3 Charcoal Ct 304 10/28/2024 1-131 0.0000 0.0000 0.0198 pCi/m3 Charcoal Ct 304 11/4/2024 1-131 0.0000 0.0000 0.0240 pCi/m3 Charcoal Ct 304 11/11/2024 1-131 0.0000 0.0000 0.0258 pCi/m3 Charcoal Ct 304 11/18/2024 1-131 0.0000 0.0000 0.0195 pCi/m3 Charcoal Ct 304 11/25/2024 1-131 0.0000 0.0000 0.0273 pCi/m3 Charcoal Ct 304 12/2/2024 1-131 0.0000 0.0000 0.0199 pCi/m3 Charcoal Ct 304 12/9/2024 1-131 0.0000 0.0000 0.0129 pCi/m3 Charcoal Ct 304 12/16/2024 1-131 0.0000 0.0000 0.0267 pCi/m3 Charcoal Ct 304 12/23/2024 1-131 0.0000 0.0000 0.0201 pCi/m3 Charcoal Ct 304 12/30/2024 1-131 0.0000 0.0000 0.0133 pCi/m3 Charcoal Ct 309 1/2/2024 1-131 0.0000 0.0000 0.0223 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 59 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Charcoal Ct 309 1/8/2024 1-131 0.0000 0.0000 0.0217 pCi/m3 Charcoal Ct 309 1/15/2024 1-131 0.0000 0.0000 0.0194 pCi/m3 Charcoal Ct 309 1/22/2024 1-131 0.0000 0.0000 0.0190 pCi/m3 Charcoal Ct 309 1/29/2024 1-131 0.0000 0.0000 0.0166 pCi/m3 Charcoal Ct 309 2/6/2024 1-131 0.0000 0.0000 0.0135 pCi/m3 Charcoal Ct 309 2/13/2024 1-131 0.0000 0.0000 0.0244 pCi/m3 Charcoal Ct 309 2/19/2024 1-131 0.0000 0.0000 0.0256 pCi/m3 Charcoal Ct 309 2/26/2024 1-131 0.0000 0.0000 0.0148 pCi/m3 Charcoal Ct 309 3/4/2024 1-131 0.0000 0.0000 0.0240 pCi/m3 Charcoal Ct 309 3/11/2024 1-131 0.0000 0.0000 0.0314 pCi/m3 Charcoal Ct 309 3/18/2024 1-131 0.0000 0.0000 0.0145 pCi/m3 Charcoal Ct 309 3/25/2024 1-131 0.0000 0.0000 0.0365 pCi/m3 Charcoal Ct 309 4/1/2024 1-131 0.0000 0.0000 0.0202 pCi/m3 Charcoal Ct 309 4/8/2024 1-131 0.0000 0.0000 0.0241 pCi/m3 Charcoal Ct 309 4/16/2024 1-131 0.0000 0.0000 0.0200 pCi/m3 Charcoal Ct 309 4/22/2024 1-131 0.0000 0.0000 0.0169 pCi/m3 Charcoal Ct 309 4/29/2024 1-131 0.0000 0.0000 0.0170 pCi/m3 Charcoal Ct 309 5/6/2024 1-131 0.0000 0.0000 0.0245 pCi/m3 Charcoal Ct 309 5/13/2024 1-131 0.0000 0.0000 0.0174 pCi/m3 Charcoal Ct 309 5/21/2024 1-131 0.0000 0.0000 0.0250 pCi/m3 Charcoal Ct 309 5/28/2024 1-131 0.0000 0.0000 0.0157 pCi/m3 Charcoal Ct 309 6/3/2024 1-131 0.0000 0.0000 0.0195 pCi/m3 Charcoal Ct 309 6/10/2024 1-131 0.0000 0.0000 0.0169 pCi/m3 Charcoal Ct 309 6/17/2024 1-131 0.0000 0.0000 0.0170 pCi/m3 Charcoal Ct 309 6/24/2024 1-131 0.0000 0.0000 0.0245 pCi/m3 Charcoal Ct 309 7/1/2024 1-131 0.0000 0.0000 0.0225 pCi/m3 Charcoal Ct 309 7/8/2024 1-131 0.0000 0.0000 0.0170 pCi/m3 Charcoal Ct 309 7/15/2024 1-131 0.0000 0.0000 0.0222 pCi/m3 Charcoal Ct 309 7/22/2024 1-131 0.0000 0.0000 0.0294 pCi/m3

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 60 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Charcoal Ct 309 7/29/2024 1-131 0.0000 0.0000 0.0213 pCi/m3 Charcoal Ct 309 8/6/2024 1-131 0.0000 0.0000 0.0141 pCi/m3 Charcoal Ct 309 8/12/2024 1-131 0.0000 0.0000 0.0192 pCi/m3 Charcoal Ct 309 8/19/2024 1-131 0.0000 0.0000 0.0191 pCi/m3 Charcoal Ct 309 8/26/2024 1-131 0.0000 0.0000 0.0253 pCi/m3 Charcoal Ct 309 9/3/2024 1-131 0.0000 0.0000 0.0183 pCi/m3 Charcoal Ct 309 9/9/2024 1-131 0.0000 0.0000 0.0198 pCi/m3 Charcoal Ct 309 9/16/2024 1-131 0.0000 0.0000 0.0196 pCi/m3 Charcoal Ct 309 9/23/2024 1-131 0.0000 0.0000 0.0191 pCi/m3 Charcoal Ct 309 10/1/2024 1-131 0.0000 0.0000 0.0140 pCi/m3 Charcoal Ct 309 10/7/2024 1-131 0.0000 0.0000 0.0208 pCi/m3 Charcoal Ct 309 10/15/2024 1-131 0.0000 0.0000 0.0142 pCi/m3 Charcoal Ct 309 10/21/2024 1-131 0.0000 0.0000 0.0265 pCi/m3 Charcoal Ct 309 10/28/2024 1-131 0.0000 0.0000 0.0147 pCi/m3 Charcoal Ct 309 11/4/2024 1-131 0.0000 0.0000 0.0242 pCi/m3 Charcoal Ct 309 11/11/2024 1-131 0.0000 0.0000 0.0243 pCi/m3 Charcoal Ct 309 11/18/2024 1-131 0.0000 0.0000 0.0177 pCi/m3 Charcoal Ct 309 11/25/2024 1-131 0.0000 0.0000 0.0308 pCi/m3 Charcoal Ct 309 12/2/2024 1-131 0.0000 0.0000 0.0112 pCi/m3 Charcoal Ct 309 12/9/2024 1-131 0.0000 0.0000 0.0240 pCi/m3 Charcoal Ct 309 12/16/2024 1-131 0.0000 0.0000 0.0240 pCi/m3 Charcoal Ct 309 12/23/2024 1-131 0.0000 0.0000 0.0277 pCi/m3 Charcoal Ct 309 12/30/2024 1-131 0.0000 0.0000 0.0213 pCi/m3 Fish Gamma 170 Bass 4/23/2024 Mn-54 0.0000 0.0000 10.3760 pCi/Kg Fish Gamma 170 Bass 4/23/2024 Fe-59 0.0000 0.0000 24.0880 pCi/Kg Fish Gamma 170 Bass 4/23/2024 Be-7 0.0000 0.0000 70.0740 pCi/Kg Fish Gamma 170 Bass 4/23/2024 Co-58 0.0000 0.0000 8.0767 pCi/Kg Fish Gamma 170 Bass 4/23/2024 Co-60 0.0000 0.0000 11.6910 pCi/Kg Fish Gamma 170 Bass 4/23/2024 Zn-65 0.0000 0.0000 27.3210 pCi/Kg

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 61 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Fish Gamma 170 Bass 4/23/2024 Cs-134 0.0000 0.0000 15.2680 pCi/Kg Fish Gamma 170 Bass 4/23/2024 Cs-137 0.0000 0.0000 8.2837 pCi/Kg Fish Gamma 170 Bass 10/30/2024 Be-7 0.0000 0.0000 56.3140 pCi/Kg Fish Gamma 170 Bass 10/30/2024 Cs-137 0.0000 0.0000 6.5736 pCi/Kg Fish Gamma 170 Bass 10/30/2024 Cs-134 0.0000 0.0000 6.0282 pCi/Kg Fish Gamma 170 Bass 10/30/2024 Zn-65 0.0000 0.0000 17.5480 pCi/Kg Fish Gamma 170 Bass 10/30/2024 Co-60 0.0000 0.0000 8.3379 pCi/Kg Fish Gamma 170 Bass 10/30/2024 Co-58 0.0000 0.0000 5.3112 pCi/Kg Fish Gamma 170 Bass 10/30/2024 Fe-59 0.0000 0.0000 17.6230 pCi/Kg Fish Gamma 170 Bass 10/30/2024 Mn-54 0.0000 0.0000 7.1325 pCi/Kg Fish Gamma 170 Carp 4/23/2024 Be-7 0.0000 0.0000 55.5280 pCi/Kg Fish Gamma 170 Carp 4/23/2024 Co-58 0.0000 0.0000 8.2617 pCi/Kg Fish Gamma 170 Carp 4/23/2024 Co-60 0.0000 0.0000 14.1660 pCi/Kg Fish Gamma 170 Carp 4/23/2024 Cs-134 0.0000 0.0000 9.9574 pCi/Kg Fish Gamma 170 Carp 4/23/2024 Mn-54 0.0000 0.0000 8.5893 pCi/Kg Fish Gamma 170 Carp 4/23/2024 Fe-59 0.0000 0.0000 27.3140 pCi/Kg Fish Gamma 170 Carp 4/23/2024 Cs-137 0.0000 0.0000 9.5850 pCi/Kg Fish Gamma 170 Carp 4/23/2024 Zn-65 0.0000 0.0000 31.7740 pCi/Kg Fish Gamma 170 Carp 10/30/2024 Be-7 0.0000 0.0000 46.5470 pCi/Kg Fish Gamma 170 Carp 10/30/2024 Co-58 0.0000 0.0000 6.9014 pCi/Kg Fish Gamma 170 Carp 10/30/2024 Co-60 0.0000 0.0000 7.7445 pCi/Kg Fish Gamma 170 Carp 10/30/2024 Cs-137 0.0000 0.0000 6.8257 pCi/Kg Fish Gamma 170 Carp 10/30/2024 Cs-134 0.0000 0.0000 6.1304 pCi/Kg Fish Gamma 170 Carp 10/30/2024 Zn-65 0.0000 0.0000 21.6920 pCi/Kg Fish Gamma 170 Carp 10/30/2024 Fe-59 0.0000 0.0000 18.3030 pCi/Kg Fish Gamma 170 Carp 10/30/2024 Mn-54 0.0000 0.0000 5.9444 pCi/Kg Fish Gamma 170 Crappie 10/30/2024 Be-7 0.0000 0.0000 53.0300 pCi/Kg Fish Gamma 170 Crappie 10/30/2024 Co-58 0.0000 0.0000 7.4830 pCi/Kg Fish Gamma 170 Crappie 10/30/2024 Co-60 0.0000 0.0000 8.4385 pCi/Kg

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 62 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Fish Gamma 170 Crappie 10/30/2024 Cs-134 0.0000 0.0000 5.4558 pCi/Kg Fish Gamma 170 Crappie 10/30/2024 Cs-137 0.0000 0.0000 6.1486 pCi/Kg Fish Gamma 170 Crappie 10/30/2024 Fe-59 0.0000 0.0000 20.1160 pCi/Kg Fish Gamma 170 Crappie 10/30/2024 Mn-54 0.0000 0.0000 8.2598 pCi/Kg Fish Gamma 170 Crappie 10/30/2024 Zn-65 0.0000 0.0000 19.2790 pCi/Kg Fish Gamma 170 Sucker 10/30/2024 Be-7 0.0000 0.0000 38.0440 pCi/Kg Fish Gamma 170 Sucker 10/30/2024 Co-58 0.0000 0.0000 5.6049 pCi/Kg Fish Gamma 170 Sucker 10/30/2024 Co-60 0.0000 0.0000 8.9594 pCi/Kg Fish Gamma 170 Sucker 10/30/2024 Cs-134 0.0000 0.0000 5.1245 pCi/Kg Fish Gamma 170 Sucker 10/30/2024 Cs-137 0.0000 0.0000 6.0660 pCi/Kg Fish Gamma 170 Sucker 10/30/2024 Fe-59 0.0000 0.0000 17.6210 pCi/Kg Fish Gamma 170 Sucker 10/30/2024 Mn-54 0.0000 0.0000 6.2146 pCi/Kg Fish Gamma 170 Sucker 10/30/2024 Zn-65 0.0000 0.0000 19.1110 pCi/Kg Fish Gamma 172 Bass 4/23/2024 Cs-137 0.0000 0.0000 12.2220 pCi/Kg Fish Gamma 172 Bass 4/23/2024 Cs-134 0.0000 0.0000 9.4089 pCi/Kg Fish Gamma 172 Bass 4/23/2024 Be-7 0.0000 0.0000 85.9690 pCi/Kg Fish Gamma 172 Bass 4/23/2024 Zn-65 0.0000 0.0000 33.2610 pCi/Kg Fish Gamma 172 Bass 4/23/2024 Co-60 0.0000 0.0000 13.4010 pCi/Kg Fish Gamma 172 Bass 4/23/2024 Co-58 0.0000 0.0000 10.2260 pCi/Kg Fish Gamma 172 Bass 4/23/2024 Fe-59 0.0000 0.0000 27.9240 pCi/Kg Fish Gamma 172 Bass 4/23/2024 Mn-54 0.0000 0.0000 9.5756 pCi/Kg Fish Gamma 172 Bass 10/30/2024 Mn-54 0.0000 0.0000 5.9100 pCi/Kg Fish Gamma 172 Bass 10/30/2024 Be-7 0.0000 0.0000 38.0710 pCi/Kg Fish Gamma 172 Bass 10/30/2024 Cs-137 16.6280 7.5263 0.0000 pCi/Kg Fish Gamma 172 Bass 10/30/2024 Cs-134 0.0000 0.0000 4.8006 pCi/Kg Fish Gamma 172 Bass 10/30/2024 Zn-65 0.0000 0.0000 16.5610 pCi/Kg Fish Gamma 172 Bass 10/30/2024 Co-60 0.0000 0.0000 6.1174 pCi/Kg Fish Gamma 172 Bass 10/30/2024 Co-58 0.0000 0.0000 5.9138 pCi/Kg Fish Gamma 172 Bass 10/30/2024 Fe-59 0.0000 0.0000 16.4470 pCi/Kg

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 63 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Fish Gamma 172 Bluegill 10/30/2024 Be-7 0.0000 0.0000 50.9700 pCi/Kg Fish Gamma 172 Bluegill 10/30/2024 Co-58 0.0000 0.0000 6.4527 pCi/Kg Fish Gamma 172 Bluegill 10/30/2024 Zn-65 0.0000 0.0000 20.3990 pCi/Kg Fish Gamma 172 Bluegill 10/30/2024 Co-60 0.0000 0.0000 9.7939 pCi/Kg Fish Gamma 172 Bluegill 10/30/2024 Fe-59 0.0000 0.0000 20.7990 pCi/Kg Fish Gamma 172 Bluegill 10/30/2024 Mn-54 0.0000 0.0000 7.3291 pCi/Kg Fish Gamma 172 Bluegill 10/30/2024 Cs-137 0.0000 0.0000 8.3339 pCi/Kg Fish Gamma 172 Bluegill 10/30/2024 Cs-134 0.0000 0.0000 7.3075 pCi/Kg Fish Gamma 172 Carp 4/23/2024 Be-7 0.0000 0.0000 66.9980 pCi/Kg Fish Gamma 172 Carp 4/23/2024 Co-58 0.0000 0.0000 8.9828 pCi/Kg Fish Gamma 172 Carp 4/23/2024 Co-60 0.0000 0.0000 12.5780 pCi/Kg Fish Gamma 172 Carp 4/23/2024 Cs-134 0.0000 0.0000 6.2850 pCi/Kg Fish Gamma 172 Carp 4/23/2024 Cs-137 0.0000 0.0000 10.1970 pCi/Kg Fish Gamma 172 Carp 4/23/2024 Zn-65 0.0000 0.0000 26.7250 pCi/Kg Fish Gamma 172 Carp 4/23/2024 Fe-59 0.0000 0.0000 24.4590 pCi/Kg Fish Gamma 172 Carp 4/23/2024 Mn-54 0.0000 0.0000 6.7273 pCi/Kg Fish Gamma 172 Carp 10/30/2024 Be-7 0.0000 0.0000 89.7360 pCi/Kg Fish Gamma 172 Carp 10/30/2024 Co-58 0.0000 0.0000 11.9100 pCi/Kg Fish Gamma 172 Carp 10/30/2024 Co-60 0.0000 0.0000 10.0710 pCi/Kg Fish Gamma 172 Carp 10/30/2024 Cs-134 0.0000 0.0000 8.4586 pCi/Kg Fish Gamma 172 Carp 10/30/2024 Cs-137 0.0000 0.0000 11.9830 pCi/Kg Fish Gamma 172 Carp 10/30/2024 Mn-54 0.0000 0.0000 11.1570 pCi/Kg Fish Gamma 172 Carp 10/30/2024 Zn-65 0.0000 0.0000 33.8770 pCi/Kg Fish Gamma 172 Carp 10/30/2024 Fe-59 0.0000 0.0000 33.6300 pCi/Kg Fish Gamma 172 Crappie 10/30/2024 Be-7 0.0000 0.0000 57.5710 pCi/Kg Fish Gamma 172 Crappie 10/30/2024 Co-58 0.0000 0.0000 6.4274 pCi/Kg Fish Gamma 172 Crappie 10/30/2024 Co-60 0.0000 0.0000 10.5870 pCi/Kg Fish Gamma 172 Crappie 10/30/2024 Cs-134 0.0000 0.0000 6.3235 pCi/Kg Fish Gamma 172 Crappie 10/30/2024 Cs-137 0.0000 0.0000 6.8735 pCi/Kg

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 64 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Fish Gamma 172 Crappie 10/30/2024 Fe-59 0.0000 0.0000 17.1640 pCi/Kg Fish Gamma 172 Crappie 10/30/2024 Zn-65 0.0000 0.0000 21.0860 pCi/Kg Fish Gamma 172 Crappie 10/30/2024 Mn-54 0.0000 0.0000 7.1328 pCi/Kg Fish Gamma 172 Sucker 10/30/2024 Be-7 0.0000 0.0000 77.5150 pCi/Kg Fish Gamma 172 Sucker 10/30/2024 Co-58 0.0000 0.0000 9.5923 pCi/Kg Fish Gamma 172 Sucker 10/30/2024 Co-60 0.0000 0.0000 16.5820 pCi/Kg Fish Gamma 172 Sucker 10/30/2024 Cs-134 0.0000 0.0000 8.2990 pCi/Kg Fish Gamma 172 Sucker 10/30/2024 Cs-137 0.0000 0.0000 12.4030 pCi/Kg Fish Gamma 172 Sucker 10/30/2024 Fe-59 0.0000 0.0000 35.5990 pCi/Kg Fish Gamma 172 Sucker 10/30/2024 Mn-54 0.0000 0.0000 11.4810 pCi/Kg Fish Gamma 172 Sucker 10/30/2024 Zn-65 0.0000 0.0000 33.2310 pCi/Kg H-3 Water 170 3/19/2024 Tritium 0.0000 0.0000 135.0000 pCi/L H-3 Water 170 6/24/2024 Tritium 0.0000 0.0000 86.6000 pCi/L H-3 Water 170 9/17/2024 Tritium 0.0000 0.0000 87.4151 pCi/L H-3 Water 170 12/23/2024 Tritium 0.0000 0.0000 89.5000 pCi/L H-3 Water 172 3/19/2024 Tritium 0.0000 0.0000 148.0000 pCi/L H-3 Water 172 6/24/2024 Tritium 0.0000 0.0000 93.0000 pCi/L H-3 Water 172 9/17/2024 Tritium 0.0000 0.0000 89.8000 pCi/L H-3 Water 172 12/23/2024 Tritium 0.0000 0.0000 151.0000 pCi/L Milk Gamma GSP 1/2/2024 Be-7 0.0000 0.0000 5.7902 pCi/L Milk Gamma GSP 1/2/2024 La-140 0.0000 0.0000 0.8839 pCi/L Milk Gamma GSP 1/2/2024 Ba-140 0.0000 0.0000 2.7057 pCi/L Milk Gamma GSP 1/2/2024 Cs-137 0.0000 0.0000 0.7170 pCi/L Milk Gamma GSP 1/2/2024 Cs-134 0.0000 0.0000 0.7356 pCi/L Milk Gamma GSP 1/2/2024 1-131 0.0000 0.0000 0.7572 pCi/L Milk Gamma GSP 1/16/2024 Be-7 0.0000 0.0000 4.5699 pCi/L Milk Gamma GSP 1/16/2024 La-140 0.0000 0.0000 0.6294 pCi/L Milk Gamma GSP 1/16/2024 Ba-140 0.0000 0.0000 2.1168 pCi/L Milk Gamma GSP 1/16/2024 Cs-137 0.0000 0.0000 0.5430 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 65 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Milk Gamma GSP 1/16/2024 Cs-134 0.0000 0.0000 0.8035 pCi/L Milk Gamma GSP 1/16/2024 1-131 0.0000 0.0000 0.7171 pCi/L Milk Gamma GSP 1/30/2024 Be-7 0.0000 0.0000 4.4783 pCi/L Milk Gamma GSP 1/30/2024 1-131 0.0000 0.0000 0.6833 pCi/L Milk Gamma GSP 1/30/2024 Cs-134 0.0000 0.0000 0.4814 pCi/L Milk Gamma GSP 1/30/2024 Cs-137 0.0000 0.0000 0.5191 pCi/L Milk Gamma GSP 1/30/2024 Ba-140 0.0000 0.0000 2.0940 pCi/L Milk Gamma GSP 1/30/2024 La-140 0.0000 0.0000 0.5966 pCi/L Milk Gamma GSP 2/13/2024 Cs-134 0.0000 0.0000 0.7436 pCi/L Milk Gamma GSP 2/13/2024 1-131 0.0000 0.0000 0.6428 pCi/L Milk Gamma GSP 2/13/2024 Be-7 0.0000 0.0000 4.4998 pCi/L Milk Gamma GSP 2/13/2024 La-140 0.0000 0.0000 0.5516 pCi/L Milk Gamma GSP 2/13/2024 Ba-140 0.0000 0.0000 1.9851 pCi/L Milk Gamma GSP 2/13/2024 Cs-137 0.0000 0.0000 0.5474 pCi/L Milk Gamma GSP 2/26/2024 Be-7 0.0000 0.0000 4.8706 pCi/L Milk Gamma GSP 2/26/2024 La-140 0.0000 0.0000 0.5691 pCi/L Milk Gamma GSP 2/26/2024 Ba-140 0.0000 0.0000 2.1837 pCi/L Milk Gamma GSP 2/26/2024 Cs-137 0.0000 0.0000 0.5986 pCi/L Milk Gamma GSP 2/26/2024 Cs-134 0.0000 0.0000 0.7687 pCi/L Milk Gamma GSP 2/26/2024 1-131 0.0000 0.0000 0.7213 pCi/L Milk Gamma GSP 3/12/2024 1-131 0.0000 0.0000 0.6753 pCi/L Milk Gamma GSP 3/12/2024 Be-7 0.0000 0.0000 4.4859 pCi/L Milk Gamma GSP 3/12/2024 La-140 0.0000 0.0000 0.5553 pCi/L Milk Gamma GSP 3/12/2024 Ba-140 0.0000 0.0000 2.0843 pCi/L Milk Gamma GSP 3/12/2024 Cs-137 0.0000 0.0000 0.5332 pCi/L Milk Gamma GSP 3/12/2024 Cs-134 0.0000 0.0000 0.5538 pCi/L Milk Gamma GSP 3/26/2024 1-131 0.0000 0.0000 0.6648 pCi/L Milk Gamma GSP 3/26/2024 Be-7 0.0000 0.0000 4.5739 pCi/L Milk Gamma GSP 3/26/2024 La-140 0.0000 0.0000 0.6043 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 66 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Milk Gamma GSP 3/26/2024 Ba-140 0.0000 0.0000 2.1334 pCi/L Milk Gamma GSP 3/26/2024 Cs-137 0.0000 0.0000 0.5576 pCi/L Milk Gamma GSP 3/26/2024 Cs-134 0.0000 0.0000 0.8613 pCi/L Milk Gamma GSP 4/9/2024 Be-7 0.0000 0.0000 4.0651 pCi/L Milk Gamma GSP 4/9/2024 La-140 0.0000 0.0000 0.5567 pCi/L Milk Gamma GSP 4/9/2024 Ba-140 0.0000 0.0000 1.8884 pCi/L Milk Gamma GSP 4/9/2024 Cs-137 0.0000 0.0000 0.4787 pCi/L Milk Gamma GSP 4/9/2024 Cs-134 0.0000 0.0000 0.7411 pCi/L Milk Gamma GSP 4/9/2024 1-131 0.0000 0.0000 0.6690 pCi/L Milk Gamma GSP 4/23/2024 Be-7 0.0000 0.0000 4.3531 pCi/L Milk Gamma GSP 4/23/2024 La-140 0.0000 0.0000 0.5800 pCi/L Milk Gamma GSP 4/23/2024 Ba-140 0.0000 0.0000 2.0562 pCi/L Milk Gamma GSP 4/23/2024 Cs-137 0.0000 0.0000 0.5436 pCi/L Milk Gamma GSP 4/23/2024 Cs-134 0.0000 0.0000 0.6779 pCi/L Milk Gamma GSP 4/23/2024 1-131 0.0000 0.0000 0.6913 pCi/L Milk Gamma GSP 5/7/2024 Be-7 0.0000 0.0000 4.6775 pCi/L Milk Gamma GSP 5/7/2024 1-131 0.0000 0.0000 0.6765 pCi/L Milk Gamma GSP 5/7/2024 Cs-134 0.0000 0.0000 0.7633 pCi/L Milk Gamma GSP 5/7/2024 Cs-137 0.0000 0.0000 0.5582 pCi/L Milk Gamma GSP 5/7/2024 Ba-140 0.0000 0.0000 2.1211 pCi/L Milk Gamma GSP 5/7/2024 La-140 0.0000 0.0000 0.5681 pCi/L Milk Gamma GSP 5/21/2024 1-131 0.0000 0.0000 0.7187 pCi/L Milk Gamma GSP 5/21/2024 Cs-134 0.0000 0.0000 0.7878 pCi/L Milk Gamma GSP 5/21/2024 Cs-137 0.0000 0.0000 0.5487 pCi/L Milk Gamma GSP 5/21/2024 Ba-140 0.0000 0.0000 2.1623 pCi/L Milk Gamma GSP 5/21/2024 La-140 0.0000 0.0000 0.6632 pCi/L Milk Gamma GSP 5/21/2024 Be-7 0.0000 0.0000 4.5666 pCi/L Milk Gamma GSP 6/4/2024 Ba-140 0.0000 0.0000 2.1384 pCi/L Milk Gamma GSP 6/4/2024 La-140 0.0000 0.0000 0.6614 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 67 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Milk Gamma GSP 6/4/2024 Cs-137 0.0000 0.0000 0.5760 pCi/L Milk Gamma GSP 6/4/2024 Cs-134 0.0000 0.0000 0.6175 pCi/L Milk Gamma GSP 6/4/2024 1-131 0.0000 0.0000 0.7136 pCi/L Milk Gamma GSP 6/4/2024 Be-7 0.0000 0.0000 4.7607 pCi/L Milk Gamma GSP 6/18/2024 Be-7 0.0000 0.0000 4.4378 pCi/L Milk Gamma GSP 6/18/2024 La-140 0.0000 0.0000 0.5543 pCi/L Milk Gamma GSP 6/18/2024 Ba-140 0.0000 0.0000 1.9311 pCi/L Milk Gamma GSP 6/18/2024 Cs-137 0.0000 0.0000 0.5481 pCi/L Milk Gamma GSP 6/18/2024 Cs-134 0.0000 0.0000 0.6073 pCi/L Milk Gamma GSP 6/18/2024 1-131 0.0000 0.0000 0.6904 pCi/L Milk Gamma GSP 7/1/2024 1-131 0.0000 0.0000 0.6986 pCi/L Milk Gamma GSP 7/1/2024 Cs-134 0.0000 0.0000 0.8490 pCi/L Milk Gamma GSP 7/1/2024 Cs-137 0.0000 0.0000 0.5410 pCi/L Milk Gamma GSP 7/1/2024 Ba-140 0.0000 0.0000 2.0975 pCi/L Milk Gamma GSP 7/1/2024 La-140 0.0000 0.0000 0.5625 pCi/L Milk Gamma GSP 7/1/2024 Be-7 0.0000 0.0000 4.6581 pCi/L Milk Gamma GSP 7/16/2024 1-131 0.0000 0.0000 0.7285 pCi/L Milk Gamma GSP 7/16/2024 Cs-134 0.0000 0.0000 1.0820 pCi/L Milk Gamma GSP 7/16/2024 Cs-137 0.0000 0.0000 0.6386 pCi/L Milk Gamma GSP 7/16/2024 Ba-140 0.0000 0.0000 2.2392 pCi/L Milk Gamma GSP 7/16/2024 La-140 0.0000 0.0000 0.6382 pCi/L Milk Gamma GSP 7/16/2024 Be-7 0.0000 0.0000 4.9614 pCi/L Milk Gamma GSP 7/30/2024 1-131 0.0000 0.0000 0.6816 pCi/L Milk Gamma GSP 7/30/2024 Cs-134 0.0000 0.0000 0.8409 pCi/L Milk Gamma GSP 7/30/2024 Cs-137 0.0000 0.0000 0.5846 pCi/L Milk Gamma GSP 7/30/2024 Ba-140 0.0000 0.0000 2.2260 pCi/L Milk Gamma GSP 7/30/2024 La-140 0.0000 0.0000 0.6460 pCi/L Milk Gamma GSP 7/30/2024 Be-7 0.0000 0.0000 4.9555 pCi/L Milk Gamma GSP 8/13/2024 Ba-140 0.0000 0.0000 2.1708 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 68 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Milk Gamma GSP 8/13/2024 Cs-137 0.0000 0.0000 0.6013 pCi/L Milk Gamma GSP 8/13/2024 1-131 0.0000 0.0000 0.7133 pCi/L Milk Gamma GSP 8/13/2024 Cs-134 0.0000 0.0000 0.5471 pCi/L Milk Gamma GSP 8/13/2024 La-140 0.0000 0.0000 0.6360 pCi/L Milk Gamma GSP 8/13/2024 Be-7 0.0000 0.0000 4.8928 pCi/L Milk Gamma GSP 8/27/2024 1-131 0.0000 0.0000 0.6910 pCi/L Milk Gamma GSP 8/27/2024 Cs-134 0.0000 0.0000 0.4903 pCi/L Milk Gamma GSP 8/27/2024 Cs-137 0.0000 0.0000 0.5109 pCi/L Milk Gamma GSP 8/27/2024 Ba-140 0.0000 0.0000 2.0484 pCi/L Milk Gamma GSP 8/27/2024 La-140 0.0000 0.0000 0.6081 pCi/L Milk Gamma GSP 8/27/2024 Be-7 0.0000 0.0000 4.6185 pCi/L Milk Gamma GSP 9/10/2024 Be-7 0.0000 0.0000 5.0303 pCi/L Milk Gamma GSP 9/10/2024 La-140 0.0000 0.0000 0.5925 pCi/L Milk Gamma GSP 9/10/2024 Ba-140 0.0000 0.0000 2.1878 pCi/L Milk Gamma GSP 9/10/2024 Cs-137 0.0000 0.0000 0.5893 pCi/L Milk Gamma GSP 9/10/2024 Cs-134 0.0000 0.0000 0.5660 pCi/L Milk Gamma GSP 9/10/2024 1-131 0.0000 0.0000 0.7044 pCi/L Milk Gamma GSP 9/24/2024 Be-7 0.0000 0.0000 4.7725 pCi/L Milk Gamma GSP 9/24/2024 La-140 0.0000 0.0000 0.6485 pCi/L Milk Gamma GSP 9/24/2024 Ba-140 0.0000 0.0000 2.2447 pCi/L Milk Gamma GSP 9/24/2024 Cs-137 0.0000 0.0000 0.6229 pCi/L Milk Gamma GSP 9/24/2024 Cs-134 0.0000 0.0000 0.5673 pCi/L Milk Gamma GSP 9/24/2024 1-131 0.0000 0.0000 0.7082 pCi/L Milk Gamma GSP 10/8/2024 Be-7 0.0000 0.0000 4.9606 pCi/L Milk Gamma GSP 10/8/2024 La-140 0.0000 0.0000 0.6301 pCi/L Milk Gamma GSP 10/8/2024 Ba-140 0.0000 0.0000 2.2559 pCi/L Milk Gamma GSP 10/8/2024 Cs-137 0.0000 0.0000 0.6095 pCi/L Milk Gamma GSP 10/8/2024 Cs-134 0.0000 0.0000 0.5354 pCi/L Milk Gamma GSP 10/8/2024 1-131 0.0000 0.0000 0.7408 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 69 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Milk Gamma GSP 10/22/2024 Be-7 0.0000 0.0000 4.9371 pCi/L Milk Gamma GSP 10/22/2024 La-140 0.0000 0.0000 0.6523 pCi/L Milk Gamma GSP 10/22/2024 Ba-140 0.0000 0.0000 2.1709 pCi/L Milk Gamma GSP 10/22/2024 Cs-137 0.0000 0.0000 0.6077 pCi/L Milk Gamma GSP 10/22/2024 Cs-134 0.0000 0.0000 0.5587 pCi/L Milk Gamma GSP 10/22/2024 1-131 0.0000 0.0000 0.7357 pCi/L Milk Gamma GSP 11/5/2024 Be-7 0.0000 0.0000 4.9361 pCi/L Milk Gamma GSP 11/5/2024 La-140 0.0000 0.0000 0.5871 pCi/L Milk Gamma GSP 11/5/2024 Ba-140 0.0000 0.0000 2.2929 pCi/L Milk Gamma GSP 11/5/2024 Cs-137 0.0000 0.0000 0.6077 pCi/L Milk Gamma GSP 11/5/2024 Cs-134 0.0000 0.0000 0.5823 pCi/L Milk Gamma GSP 11/5/2024 1-131 0.0000 0.0000 0.7326 pCi/L Milk Gamma GSP 11/18/2024 Be-7 0.0000 0.0000 4.9720 pCi/L Milk Gamma GSP 11/18/2024 La-140 0.0000 0.0000 0.6143 pCi/L Milk Gamma GSP 11/18/2024 Ba-140 0.0000 0.0000 2.3384 pCi/L Milk Gamma GSP 11/18/2024 Cs-137 0.0000 0.0000 0.6050 pCi/L Milk Gamma GSP 11/18/2024 Cs-134 0.0000 0.0000 0.5797 pCi/L Milk Gamma GSP 11/18/2024 1-131 0.0000 0.0000 0.7272 pCi/L Milk Gamma GSP 12/3/2024 1-131 0.0000 0.0000 0.7225 pCi/L Milk Gamma GSP 12/3/2024 Cs-134 0.0000 0.0000 0.5492 pCi/L Milk Gamma GSP 12/3/2024 Cs-137 0.0000 0.0000 0.6185 pCi/L Milk Gamma GSP 12/3/2024 Ba-140 0.0000 0.0000 2.2013 pCi/L Milk Gamma GSP 12/3/2024 La-140 0.0000 0.0000 0.6409 pCi/L Milk Gamma GSP 12/3/2024 Be-7 0.0000 0.0000 5.0503 pCi/L Milk Gamma GSP 12/17/2024 1-131 0.0000 0.0000 0.7261 pCi/L Milk Gamma GSP 12/17/2024 Cs-134 0.0000 0.0000 0.5431 pCi/L Milk Gamma GSP 12/17/2024 Cs-137 0.0000 0.0000 0.6013 pCi/L Milk Gamma GSP 12/17/2024 Ba-140 0.0000 0.0000 2.1785 pCi/L Milk Gamma GSP 12/17/2024 La-140 0.0000 0.0000 0.6122 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 70 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Milk Gamma GSP 12/17/2024 Be-7 0.0000 0.0000 5.0570 pCi/L Milk Gamma GSP 12/30/2024 Be-7 0.0000 0.0000 3.8270 pCi/L Milk Gamma GSP 12/30/2024 1-131 0.0000 0.0000 0.6467 pCi/L Milk Gamma GSP 12/30/2024 Cs-134 0.0000 0.0000 0.4259 pCi/L Milk Gamma GSP 12/30/2024 Cs-137 0.0000 0.0000 0.4552 pCi/L Milk Gamma GSP 12/30/2024 Ba-140 0.0000 0.0000 1.8880 pCi/L Milk Gamma GSP 12/30/2024 La-140 0.0000 0.0000 0.5166 pCi/L River Water 170 1/23/2024 Co-60 0.0000 0.0000 7.1520 pCi/L River Water 170 1/23/2024 Zn-65 0.0000 0.0000 12.9600 pCi/L River Water 170 1/23/2024 Zr-95 0.0000 0.0000 10.8960 pCi/L River Water 170 1/23/2024 Nb-95 0.0000 0.0000 5.8696 pCi/L River Water 170 1/23/2024 1-131 0.0000 0.0000 5.2233 pCi/L River Water 170 1/23/2024 Cs-134 0.0000 0.0000 7.9445 pCi/L River Water 170 1/23/2024 Cs-137 0.0000 0.0000 5.8940 pCi/L River Water 170 1/23/2024 Ba-140 0.0000 0.0000 18.7360 pCi/L River Water 170 1/23/2024 La-140 0.0000 0.0000 8.7751 pCi/L River Water 170 1/23/2024 Be-7 0.0000 0.0000 48.8120 pCi/L River Water 170 1/23/2024 Mn-54 0.0000 0.0000 5.2529 pCi/L River Water 170 1/23/2024 Fe-59 0.0000 0.0000 8.7035 pCi/L River Water 170 1/23/2024 Co-58 0.0000 0.0000 4.3308 pCi/L River Water 170 2/20/2024 Mn-54 0.0000 0.0000 3.4004 pCi/L River Water 170 2/20/2024 Fe-59 0.0000 0.0000 10.2320 pCi/L River Water 170 2/20/2024 Co-58 0.0000 0.0000 4.8838 pCi/L River Water 170 2/20/2024 Co-60 0.0000 0.0000 4.7793 pCi/L River Water 170 2/20/2024 Zn-65 0.0000 0.0000 12.9550 pCi/L River Water 170 2/20/2024 Zr-95 0.0000 0.0000 9.9757 pCi/L River Water 170 2/20/2024 Nb-95 0.0000 0.0000 5.0736 pCi/L River Water 170 2/20/2024 1-131 0.0000 0.0000 5.1614 pCi/L River Water 170 2/20/2024 Cs-134 0.0000 0.0000 7.7810 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 71 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units River Water 170 2/20/2024 Cs-137 0.0000 0.0000 5.8939 pCi/L River Water 170 2/20/2024 Ba-140 0.0000 0.0000 16.3140 pCi/L River Water 170 2/20/2024 La-140 0.0000 0.0000 8.2736 pCi/L River Water 170 2/20/2024 Be-7 0.0000 0.0000 44.6100 pCi/L River Water 170 3/19/2024 Zr-95 0.0000 0.0000 8.5710 pCi/L River Water 170 3/19/2024 Nb-95 0.0000 0.0000 9.7771 pCi/L River Water 170 3/19/2024 1-131 0.0000 0.0000 6.9346 pCi/L River Water 170 3/19/2024 Cs-134 0.0000 0.0000 8.0227 pCi/L River Water 170 3/19/2024 Cs-137 0.0000 0.0000 6.2315 pCi/L River Water 170 3/19/2024 Ba-140 0.0000 0.0000 22.6870 pCi/L River Water 170 3/19/2024 La-140 0.0000 0.0000 8.5676 pCi/L River Water 170 3/19/2024 Be-7 0.0000 0.0000 51.1700 pCi/L River Water 170 3/19/2024 Mn-54 0.0000 0.0000 6.8675 pCi/L River Water 170 3/19/2024 Fe-59 0.0000 0.0000 10.5830 pCi/L River Water 170 3/19/2024 Co-58 0.0000 0.0000 4.7816 pCi/L River Water 170 3/19/2024 Co-60 0.0000 0.0000 6.3101 pCi/L River Water 170 3/19/2024 Zn-65 0.0000 0.0000 23.2540 pCi/L River Water 170 4/29/2024 Mn-54 0.0000 0.0000 3.6435 pCi/L River Water 170 4/29/2024 Fe-59 0.0000 0.0000 6.6788 pCi/L River Water 170 4/29/2024 Co-58 0.0000 0.0000 2.7613 pCi/L River Water 170 4/29/2024 Co-60 0.0000 0.0000 3.3580 pCi/L River Water 170 4/29/2024 Zn-65 0.0000 0.0000 6.2288 pCi/L River Water 170 4/29/2024 Zr-95 0.0000 0.0000 4.6747 pCi/L River Water 170 4/29/2024 Nb-95 0.0000 0.0000 2.9569 pCi/L River Water 170 4/29/2024 1-131 0.0000 0.0000 3.7927 pCi/L River Water 170 4/29/2024 Cs-134 0.0000 0.0000 2.8543 pCi/L River Water 170 4/29/2024 Cs-137 0.0000 0.0000 3.0810 pCi/L River Water 170 4/29/2024 Ba-140 0.0000 0.0000 12.4200 pCi/L River Water 170 4/29/2024 La-140 0.0000 0.0000 4.6157 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 72 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units River Water 170 4/29/2024 Be-7 0.0000 0.0000 24.5010 pCi/L River Water 170 5/27/2024 Co-58 0.0000 0.0000 2.7535 pCi/L River Water 170 5/27/2024 Fe-59 0.0000 0.0000 6.8093 pCi/L River Water 170 5/27/2024 Co-60 0.0000 0.0000 3.8722 pCi/L River Water 170 5/27/2024 Zn-65 0.0000 0.0000 6.9022 pCi/L River Water 170 5/27/2024 Zr-95 0.0000 0.0000 4.4359 pCi/L River Water 170 5/27/2024 Nb-95 0.0000 0.0000 2.8845 pCi/L River Water 170 5/27/2024 1-131 0.0000 0.0000 4.2339 pCi/L River Water 170 5/27/2024 Cs-134 0.0000 0.0000 2.9538 pCi/L River Water 170 5/27/2024 Cs-137 0.0000 0.0000 3.2615 pCi/L River Water 170 5/27/2024 Ba-140 0.0000 0.0000 12.7120 pCi/L River Water 170 5/27/2024 La-140 0.0000 0.0000 3.3054 pCi/L River Water 170 5/27/2024 Be-7 0.0000 0.0000 24.6710 pCi/L River Water 170 5/27/2024 Mn-54 0.0000 0.0000 2.8014 pCi/L River Water 170 6/24/2024 Co-60 0.0000 0.0000 6.6103 pCi/L River Water 170 6/24/2024 Zn-65 0.0000 0.0000 10.6200 pCi/L River Water 170 6/24/2024 Zr-95 0.0000 0.0000 7.2050 pCi/L River Water 170 6/24/2024 Nb-95 0.0000 0.0000 5.1800 pCi/L River Water 170 6/24/2024 1-131 0.0000 0.0000 5.0747 pCi/L River Water 170 6/24/2024 Cs-134 0.0000 0.0000 4.6635 pCi/L River Water 170 6/24/2024 Mn-54 0.0000 0.0000 4.1909 pCi/L River Water 170 6/24/2024 Fe-59 0.0000 0.0000 11.3020 pCi/L River Water 170 6/24/2024 Cs-137 0.0000 0.0000 4.3902 pCi/L River Water 170 6/24/2024 Ba-140 0.0000 0.0000 18.7590 pCi/L River Water 170 6/24/2024 La-140 0.0000 0.0000 6.0688 pCi/L River Water 170 6/24/2024 Be-7 0.0000 0.0000 37.7430 pCi/L River Water 170 6/24/2024 Co-58 0.0000 0.0000 3.7122 pCi/L River Water 170 7/23/2024 Zr-95 0.0000 0.0000 7.7834 pCi/L River Water 170 7/23/2024 Zn-65 0.0000 0.0000 10.0930 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 73 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units River Water 170 7/23/2024 Nb-95 0.0000 0.0000 4.6365 pCi/L River Water 170 7/23/2024 1-131 0.0000 0.0000 4.8246 pCi/L River Water 170 7/23/2024 Cs-134 0.0000 0.0000 6.1768 pCi/L River Water 170 7/23/2024 Cs-137 0.0000 0.0000 4.8317 pCi/L River Water 170 7/23/2024 Ba-140 0.0000 0.0000 16.3000 pCi/L River Water 170 7/23/2024 La-140 0.0000 0.0000 4.5438 pCi/L River Water 170 7/23/2024 Be-7 0.0000 0.0000 39.3450 pCi/L River Water 170 7/23/2024 Fe-59 0.0000 0.0000 11.0950 pCi/L River Water 170 7/23/2024 Mn-54 0.0000 0.0000 3.9938 pCi/L River Water 170 7/23/2024 Co-58 0.0000 0.0000 4.5025 pCi/L River Water 170 7/23/2024 Co-60 0.0000 0.0000 5.5625 pCi/L River Water 170 9/17/2024 Mn-54 0.0000 0.0000 3.8776 pCi/L River Water 170 9/17/2024 Fe-59 0.0000 0.0000 9.1733 pCi/L River Water 170 9/17/2024 Co-58 0.0000 0.0000 4.1965 pCi/L River Water 170 9/17/2024 Co-60 0.0000 0.0000 5.5624 pCi/L River Water 170 9/17/2024 Zn-65 0.0000 0.0000 11.0540 pCi/L River Water 170 9/17/2024 Zr-95 0.0000 0.0000 9.1468 pCi/L River Water 170 9/17/2024 Nb-95 0.0000 0.0000 4.4536 pCi/L River Water 170 9/17/2024 1-131 0.0000 0.0000 5.1645 pCi/L River Water 170 9/17/2024 Cs-134 0.0000 0.0000 5.2264 pCi/L River Water 170 9/17/2024 Cs-137 0.0000 0.0000 5.0103 pCi/L River Water 170 9/17/2024 Ba-140 0.0000 0.0000 15.6850 pCi/L River Water 170 9/17/2024 La-140 0.0000 0.0000 6.3506 pCi/L River Water 170 9/17/2024 Be-7 0.0000 0.0000 38.3150 pCi/L River Water 170 10/29/2024 1-131 0.0000 0.0000 4.9877 pCi/L River Water 170 10/29/2024 Cs-134 0.0000 0.0000 4.6465 pCi/L River Water 170 10/29/2024 Cs-137 0.0000 0.0000 5.0103 pCi/L River Water 170 10/29/2024 Ba-140 0.0000 0.0000 15.6100 pCi/L River Water 170 10/29/2024 La-140 0.0000 0.0000 6.5606 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 7 4 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units River Water 170 10/29/2024 Be-7 0.0000 0.0000 37.7550 pCi/L River Water 170 10/29/2024 Mn-54 0.0000 0.0000 4.3173 pCi/L River Water 170 10/29/2024 Nb-95 0.0000 0.0000 5.0396 pCi/L River Water 170 10/29/2024 Zr-95 0.0000 0.0000 7.4274 pCi/L River Water 170 10/29/2024 Zn-65 0.0000 0.0000 11.3500 pCi/L River Water 170 10/29/2024 Co-60 0.0000 0.0000 5.1368 pCi/L River Water 170 10/29/2024 Co-58 0.0000 0.0000 4.4969 pCi/L River Water 170 10/29/2024 Fe-59 0.0000 0.0000 10.8250 pCi/L River Water 170 11/25/2024 Co-58 0.0000 0.0000 2.4044 pCi/L River Water 170 11/25/2024 Co-60 0.0000 0.0000 3.0264 pCi/L River Water 170 11/25/2024 Zn-65 0.0000 0.0000 6.2166 pCi/L River Water 170 11/25/2024 Zr-95 0.0000 0.0000 4.5660 pCi/L River Water 170 11/25/2024 1-131 0.0000 0.0000 4.5608 pCi/L River Water 170 11/25/2024 Nb-95 0.0000 0.0000 2.9054 pCi/L River Water 170 11/25/2024 Cs-134 0.0000 0.0000 2.4682 pCi/L River Water 170 11/25/2024 Cs-137 0.0000 0.0000 2.4723 pCi/L River Water 170 11/25/2024 Ba-140 0.0000 0.0000 12.8820 pCi/L River Water 170 11/25/2024 Be-7 0.0000 0.0000 21.9590 pCi/L River Water 170 11/25/2024 La-140 0.0000 0.0000 4.3763 pCi/L River Water 170 11/25/2024 Mn-54 0.0000 0.0000 2.3078 pCi/L River Water 170 11/25/2024 Fe-59 0.0000 0.0000 6.3200 pCi/L River Water 170 12/23/2024 Co-58 0.0000 0.0000 2.5674 pCi/L River Water 170 12/23/2024 Co-60 0.0000 0.0000 3.1644 pCi/L River Water 170 12/23/2024 Zn-65 0.0000 0.0000 7.0868 pCi/L River Water 170 12/23/2024 Zr-95 0.0000 0.0000 4.8838 pCi/L River Water 170 12/23/2024 Nb-95 0.0000 0.0000 2.8109 pCi/L River Water 170 12/23/2024 1-131 0.0000 0.0000 3.9365 pCi/L River Water 170 12/23/2024 Cs-134 0.0000 0.0000 2.6821 pCi/L River Water 170 12/23/2024 Cs-137 0.0000 0.0000 3.0271 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 75 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units River Water 170 12/23/2024 Ba-140 0.0000 0.0000 11.8560 pCi/L River Water 170 12/23/2024 La-140 0.0000 0.0000 4.1171 pCi/L River Water 170 12/23/2024 Be-7 0.0000 0.0000 25.6610 pCi/L River Water 170 12/23/2024 Mn-54 0.0000 0.0000 2.8803 pCi/L River Water 170 12/23/2024 Fe-59 0.0000 0.0000 7.0656 pCi/L River Water 172 1/23/2024 Mn-54 0.0000 0.0000 7.7590 pCi/L River Water 172 1/23/2024 Fe-59 0.0000 0.0000 9.7696 pCi/L River Water 172 1/23/2024 Co-58 0.0000 0.0000 4.0894 pCi/L River Water 172 1/23/2024 Co-60 0.0000 0.0000 6.1337 pCi/L River Water 172 1/23/2024 Zn-65 0.0000 0.0000 12.4650 pCi/L River Water 172 1/23/2024 Zr-95 0.0000 0.0000 7.9473 pCi/L River Water 172 1/23/2024 Nb-95 0.0000 0.0000 7.3537 pCi/L River Water 172 1/23/2024 1-131 0.0000 0.0000 5.3726 pCi/L River Water 172 1/23/2024 Cs-134 0.0000 0.0000 6.4111 pCi/L River Water 172 1/23/2024 Cs-137 0.0000 0.0000 4.8316 pCi/L River Water 172 1/23/2024 Ba-140 0.0000 0.0000 15.3980 pCi/L River Water 172 1/23/2024 La-140 0.0000 0.0000 7.6664 pCi/L River Water 172 1/23/2024 Be-7 0.0000 0.0000 42.6520 pCi/L River Water 172 2/20/2024 Mn-54 0.0000 0.0000 5.8199 pCi/L River Water 172 2/20/2024 Fe-59 0.0000 0.0000 10.3150 pCi/L River Water 172 2/20/2024 Co-58 0.0000 0.0000 4.6889 pCi/L River Water 172 2/20/2024 Co-60 0.0000 0.0000 4.9063 pCi/L River Water 172 2/20/2024 Zn-65 0.0000 0.0000 11.6420 pCi/L River Water 172 2/20/2024 Zr-95 0.0000 0.0000 8.2629 pCi/L River Water 172 2/20/2024 Nb-95 0.0000 0.0000 4.6299 pCi/L River Water 172 2/20/2024 1-131 0.0000 0.0000 5.4149 pCi/L River Water 172 2/20/2024 Cs-134 0.0000 0.0000 5.5410 pCi/L River Water 172 2/20/2024 Cs-137 0.0000 0.0000 4.7392 pCi/L River Water 172 2/20/2024 Ba-140 0.0000 0.0000 15.9490 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 76 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units River Water 172 2/20/2024 La-140 0.0000 0.0000 5.2271 pCi/L River Water 172 2/20/2024 Be-7 0.0000 0.0000 39.3080 pCi/L River Water 172 3/19/2024 Zr-95 0.0000 0.0000 11.2920 pCi/L River Water 172 3/19/2024 Nb-95 0.0000 0.0000 5.6168 pCi/L River Water 172 3/19/2024 1-131 0.0000 0.0000 8.2093 pCi/L River Water 172 3/19/2024 Cs-134 0.0000 0.0000 10.5180 pCi/L River Water 172 3/19/2024 Cs-137 0.0000 0.0000 7.8192 pCi/L River Water 172 3/19/2024 Ba-140 0.0000 0.0000 25.9110 pCi/L River Water 172 3/19/2024 La-140 0.0000 0.0000 10.6200 pCi/L River Water 172 3/19/2024 Be-7 0.0000 0.0000 61.0000 pCi/L River Water 172 3/19/2024 Mn-54 0.0000 0.0000 6.9103 pCi/L River Water 172 3/19/2024 Fe-59 0.0000 0.0000 14.4970 pCi/L River Water 172 3/19/2024 Co-58 0.0000 0.0000 6.2684 pCi/L River Water 172 3/19/2024 Co-60 0.0000 0.0000 7.5774 pCi/L River Water 172 3/19/2024 Zn-65 0.0000 0.0000 17.3750 pCi/L River Water 172 4/29/2024 Co-58 0.0000 0.0000 2.3251 pCi/L River Water 172 4/29/2024 Co-60 0.0000 0.0000 3.1647 pCi/L River Water 172 4/29/2024 Zn-65 0.0000 0.0000 7.0915 pCi/L River Water 172 4/29/2024 Zr-95 0.0000 0.0000 4.2796 pCi/L River Water 172 4/29/2024 Nb-95 0.0000 0.0000 3.0211 pCi/L River Water 172 4/29/2024 1-131 0.0000 0.0000 3.9921 pCi/L River Water 172 4/29/2024 Cs-134 0.0000 0.0000 2.8030 pCi/L River Water 172 4/29/2024 Cs-137 0.0000 0.0000 3.2365 pCi/L River Water 172 4/29/2024 Ba-140 0.0000 0.0000 11.4580 pCi/L River Water 172 4/29/2024 La-140 0.0000 0.0000 4.5007 pCi/L River Water 172 4/29/2024 Be-7 0.0000 0.0000 27.1530 pCi/L River Water 172 4/29/2024 Fe-59 0.0000 0.0000 5.9064 pCi/L River Water 172 4/29/2024 Mn-54 0.0000 0.0000 3.7601 pCi/L River Water 172 5/27/2024 Mn-54 0.0000 0.0000 4.1304 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 77 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units River Water 172 5/27/2024 Fe-59 0.0000 0.0000 5.8526 pCi/L River Water 172 5/27/2024 Co-58 0.0000 0.0000 2.9266 pCi/L River Water 172 5/27/2024 Co-60 0.0000 0.0000 3.2300 pCi/L River Water 172 5/27/2024 Zn-65 0.0000 0.0000 7.1677 pCi/L River Water 172 5/27/2024 Zr-95 0.0000 0.0000 5.2121 pCi/L River Water 172 5/27/2024 Nb-95 0.0000 0.0000 2.6103 pCi/L River Water 172 5/27/2024 1-131 0.0000 0.0000 4.0137 pCi/L River Water 172 5/27/2024 Cs-134 0.0000 0.0000 3.4895 pCi/L River Water 172 5/27/2024 Cs-137 0.0000 0.0000 3.1597 pCi/L River Water 172 5/27/2024 Ba-140 0.0000 0.0000 11.4500 pCi/L River Water 172 5/27/2024 La-140 0.0000 0.0000 3.7746 pCi/L River Water 172 5/27/2024 Be-7 0.0000 0.0000 25.6900 pCi/L River Water 172 6/24/2024 Nb-95 0.0000 0.0000 5.1739 pCi/L River Water 172 6/24/2024 Zr-95 0.0000 0.0000 7.7009 pCi/L River Water 172 6/24/2024 1-131 0.0000 0.0000 5.1922 pCi/L River Water 172 6/24/2024 Cs-134 0.0000 0.0000 7.7477 pCi/L River Water 172 6/24/2024 Cs-137 0.0000 0.0000 4.3753 pCi/L River Water 172 6/24/2024 Ba-140 0.0000 0.0000 16.5220 pCi/L River Water 172 6/24/2024 La-140 0.0000 0.0000 5.7180 pCi/L River Water 172 6/24/2024 Be-7 0.0000 0.0000 34.0320 pCi/L River Water 172 6/24/2024 Mn-54 0.0000 0.0000 6.1178 pCi/L River Water 172 6/24/2024 Fe-59 0.0000 0.0000 8.5517 pCi/L River Water 172 6/24/2024 Co-58 0.0000 0.0000 4.4504 pCi/L River Water 172 6/24/2024 Co-60 0.0000 0.0000 5.7628 pCi/L River Water 172 6/24/2024 Zn-65 0.0000 0.0000 9.5777 pCi/L River Water 172 7/23/2024 Zr-95 0.0000 0.0000 10.4730 pCi/L River Water 172 7/23/2024 Nb-95 0.0000 0.0000 5.0066 pCi/L River Water 172 7/23/2024 1-131 0.0000 0.0000 5.7134 pCi/L River Water 172 7/23/2024 Cs-134 0.0000 0.0000 5.2859 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 78 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units River Water 172 7/23/2024 Cs-137 0.0000 0.0000 5.7069 pCi/L River Water 172 7/23/2024 Ba-140 0.0000 0.0000 20.0230 pCi/L River Water 172 7/23/2024 La-140 0.0000 0.0000 8.0929 pCi/L River Water 172 7/23/2024 Be-7 0.0000 0.0000 38.9010 pCi/L River Water 172 7/23/2024 Mn-54 0.0000 0.0000 4.3311 pCi/L River Water 172 7/23/2024 Fe-59 0.0000 0.0000 11.9280 pCi/L River Water 172 7/23/2024 Co-58 0.0000 0.0000 5.9335 pCi/L River Water 172 7/23/2024 Co-60 0.0000 0.0000 7.1979 pCi/L River Water 172 7/23/2024 Zn-65 0.0000 0.0000 14.9070 pCi/L River Water 172 9/17/2024 Mn-54 0.0000 0.0000 5.8058 pCi/L River Water 172 9/17/2024 Fe-59 0.0000 0.0000 14.4960 pCi/L River Water 172 9/17/2024 Co-58 0.0000 0.0000 4.0344 pCi/L River Water 172 9/17/2024 Co-60 0.0000 0.0000 7.9335 pCi/L River Water 172 9/17/2024 Zn-65 0.0000 0.0000 13.1540 pCi/L River Water 172 9/17/2024 Zr-95 0.0000 0.0000 10.4880 pCi/L River Water 172 9/17/2024 Nb-95 0.0000 0.0000 5.8871 pCi/L River Water 172 9/17/2024 1-131 0.0000 0.0000 5.4147 pCi/L River Water 172 9/17/2024 Cs-134 0.0000 0.0000 4.7765 pCi/L River Water 172 9/17/2024 Cs-137 0.0000 0.0000 5.8775 pCi/L River Water 172 9/17/2024 Ba-140 0.0000 0.0000 15.7010 pCi/L River Water 172 9/17/2024 La-140 0.0000 0.0000 9.4900 pCi/L River Water 172 9/17/2024 Be-7 0.0000 0.0000 46.8440 pCi/L River Water 172 10/29/2024 La-140 0.0000 0.0000 7.7308 pCi/L River Water 172 10/29/2024 Be-7 0.0000 0.0000 42.9430 pCi/L River Water 172 10/29/2024 Mn-54 0.0000 0.0000 7.1460 pCi/L River Water 172 10/29/2024 Fe-59 0.0000 0.0000 12.5760 pCi/L River Water 172 10/29/2024 Co-58 0.0000 0.0000 4.6762 pCi/L River Water 172 10/29/2024 Zn-65 0.0000 0.0000 12.8790 pCi/L River Water 172 10/29/2024 Co-60 0.0000 0.0000 7.4259 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 79 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units River Water 172 10/29/2024 Ba-140 0.0000 0.0000 19.7370 pCi/L River Water 172 10/29/2024 Cs-137 0.0000 0.0000 4.6385 pCi/L River Water 172 10/29/2024 Cs-134 0.0000 0.0000 6.0604 pCi/L River Water 172 10/29/2024 1-131 0.0000 0.0000 3.7583 pCi/L River Water 172 10/29/2024 Nb-95 0.0000 0.0000 4.8368 pCi/L River Water 172 10/29/2024 Zr-95 0.0000 0.0000 6.2247 pCi/L River Water 172 11/25/2024 1-131 0.0000 0.0000 5.3525 pCi/L River Water 172 11/25/2024 Cs-134 0.0000 0.0000 3.2035 pCi/L River Water 172 11/25/2024 Cs-137 0.0000 0.0000 2.8009 pCi/L River Water 172 11/25/2024 Ba-140 0.0000 0.0000 13.9370 pCi/L River Water 172 11/25/2024 La-140 0.0000 0.0000 6.2691 pCi/L River Water 172 11/25/2024 Be-7 0.0000 0.0000 25.7080 pCi/L River Water 172 11/25/2024 Mn-54 0.0000 0.0000 3.2038 pCi/L River Water 172 11/25/2024 Fe-59 0.0000 0.0000 6.7985 pCi/L River Water 172 11/25/2024 Co-58 0.0000 0.0000 2.9558 pCi/L River Water 172 11/25/2024 Co-60 0.0000 0.0000 4.0780 pCi/L River Water 172 11/25/2024 Zn-65 0.0000 0.0000 6.0830 pCi/L River Water 172 11/25/2024 Zr-95 0.0000 0.0000 5.4727 pCi/L River Water 172 11/25/2024 Nb-95 0.0000 0.0000 3.4987 pCi/L River Water 172 12/23/2024 Zr-95 0.0000 0.0000 5.9418 pCi/L River Water 172 12/23/2024 Nb-95 0.0000 0.0000 3.7199 pCi/L River Water 172 12/23/2024 1-131 0.0000 0.0000 4.1616 pCi/L River Water 172 12/23/2024 Cs-134 0.0000 0.0000 3.6312 pCi/L River Water 172 12/23/2024 Cs-137 0.0000 0.0000 3.8906 pCi/L River Water 172 12/23/2024 Ba-140 0.0000 0.0000 13.9440 pCi/L River Water 172 12/23/2024 La-140 0.0000 0.0000 5.3525 pCi/L River Water 172 12/23/2024 Be-7 0.0000 0.0000 29.5250 pCi/L River Water 172 12/23/2024 Mn-54 0.0000 0.0000 2.8781 pCi/L River Water 172 12/23/2024 Fe-59 0.0000 0.0000 8.6986 pCi/L

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 80 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units River Water 172 12/23/2024 Co-58 0.0000 0.0000 3.1802 pCi/L River Water 172 12/23/2024 Co-60 0.0000 0.0000 4.2325 pCi/L River Water 172 12/23/2024 Zn-65 0.0000 0.0000 8.8089 pCi/L Sediment 170 4/29/2024 Co-58 0.0000 0.0000 5.3254 pCi/Kg Sediment 170 4/29/2024 Co-60 0.0000 0.0000 7.4455 pCi/Kg Sediment 170 4/29/2024 Cs-134 0.0000 0.0000 4.8914 pCi/Kg Sediment 170 4/29/2024 Cs-137 0.0000 0.0000 5.9202 pCi/Kg Sediment 170 4/29/2024 Be-7 0.0000 0.0000 48.1150 pCi/Kg Sediment 170 10/25/2024 Be-7 0.0000 0.0000 63.0840 pCi/Kg Sediment 170 10/25/2024 Cs-137 0.0000 0.0000 7.1712 pCi/Kg Sediment 170 10/25/2024 Cs-134 0.0000 0.0000 9.8972 pCi/Kg Sediment 170 10/25/2024 Co-60 0.0000 0.0000 8.5671 pCi/Kg Sediment 170 10/25/2024 Co-58 0.0000 0.0000 6.7092 pCi/Kg Sediment 172 4/29/2024 Cs-137 0.0000 0.0000 7.0238 pCi/Kg Sediment 172 4/29/2024 Co-58 0.0000 0.0000 7.4718 pCi/Kg Sediment 172 4/29/2024 Be-7 0.0000 0.0000 54.8460 pCi/Kg Sediment 172 4/29/2024 Cs-134 0.0000 0.0000 8.3279 pCi/Kg Sediment 172 4/29/2024 Co-60 0.0000 0.0000 9.2408 pCi/Kg Sediment 172 10/25/2024 Co-60 0.0000 0.0000 5.5383 pCi/Kg Sediment 172 10/25/2024 Co-58 0.0000 0.0000 9.5957 pCi/Kg Sediment 172 10/25/2024 Be-7 0.0000 0.0000 38.2240 pCi/Kg Sediment 172 10/25/2024 Cs-137 0.0000 0.0000 8.2249 pCi/Kg Sediment 172 10/25/2024 Cs-134 0.0000 0.0000 4.1117 pCi/Kg Vegetation 106 1/29/2024 Be-7 11954.0000 1097.6000 0.0000 pCi/Kg Vegetation 106 1/29/2024 Cs-137 0.0000 0.0000 29.7900 pCi/Kg Vegetation 106 1/29/2024 Cs-134 0.0000 0.0000 43.1490 pCi/Kg Vegetation 106 1/29/2024 1-131 0.0000 0.0000 34.2300 pCi/Kg Vegetation 106 3/25/2024 Be-7 14956.0000 1221.2000 0.0000 pCi/Kg Vegetation 106 3/25/2024 Cs-137 112.9200 20.5280 0.0000 pCi/Kg

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 81 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Vegetation 106 3/25/2024 Cs-134 0.0000 0.0000 25.3250 pCi/Kg Vegetation 106 3/25/2024 1-131 0.0000 0.0000 20.6030 pCi/Kg Vegetation 106 4/29/2024 1-131 0.0000 0.0000 10.1580 pCi/Kg Vegetation 106 4/29/2024 Be-7 3675.7000 333.0400 0.0000 pCi/Kg Vegetation 106 4/29/2024 Cs-137 40.9340 11.7850 0.0000 pCi/Kg Vegetation 106 4/29/2024 Cs-134 0.0000 0.0000 7.9813 pCi/Kg Vegetation 106 5/28/2024 Be-7 3177.3000 356.2100 0.0000 pCi/Kg Vegetation 106 5/28/2024 Cs-137 116.3800 25.6000 0.0000 pCi/Kg Vegetation 106 5/28/2024 Cs-134 0.0000 0.0000 21.8800 pCi/Kg Vegetation 106 5/28/2024 1-131 0.0000 0.0000 21.6170 pCi/Kg Vegetation 106 6/24/2024 1-131 0.0000 0.0000 19.2070 pCi/Kg Vegetation 106 6/24/2024 Cs-134 0.0000 0.0000 20.5920 pCi/Kg Vegetation 106 6/24/2024 Cs-137 41.4910 20.4530 0.0000 pCi/Kg Vegetation 106 6/24/2024 Be-7 2040.4000 286.0900 0.0000 pCi/Kg Vegetation 106 7/29/2024 1-131 0.0000 0.0000 10.6860 pCi/Kg Vegetation 106 7/29/2024 Cs-134 0.0000 0.0000 10.9230 pCi/Kg Vegetation 106 7/29/2024 Cs-137 72.5870 13.6690 0.0000 pCi/Kg Vegetation 106 7/29/2024 Be-7 4047.2000 359.0500 0.0000 pCi/Kg Vegetation 106 8/26/2024 Cs-137 68.2880 18.4940 0.0000 pCi/Kg Vegetation 106 8/26/2024 Be-7 2384.3780 282.0490 0.0000 pCi/Kg Vegetation 106 8/26/2024 1-131 0.0000 0.0000 43.5860 pCi/Kg Vegetation 106 8/26/2024 Cs-134 0.0000 0.0000 12.6040 pCi/Kg Vegetation 106 10/1/2024 1-131 0.0000 0.0000 10.7790 pCi/Kg Vegetation 106 10/1/2024 Cs-134 0.0000 0.0000 9.9997 pCi/Kg Vegetation 106 10/1/2024 Cs-137 56.2640 15.3280 0.0000 pCi/Kg Vegetation 106 10/1/2024 Be-7 1400.6000 175.8200 0.0000 pCi/Kg Vegetation 106 10/28/2024 1-131 0.0000 0.0000 16.5300 pCi/Kg Vegetation 106 10/28/2024 Cs-134 0.0000 0.0000 13.6410 pCi/Kg Vegetation 106 10/28/2024 Cs-137 0.0000 0.0000 14.3290 pCi/Kg

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 82 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Vegetation 106 10/28/2024 Be-7 1509.8000 232.4200 0.0000 pCi/Kg Vegetation 106 11/25/2024 Cs-134 0.0000 0.0000 12.8290 pCi/Kg Vegetation 106 11/25/2024 Cs-137 77.6070 18.2530 0.0000 pCi/Kg Vegetation 106 11/25/2024 1-131 0.0000 0.0000 27.6490 pCi/Kg Vegetation 106 11/25/2024 Be-7 5806.9000 478.8100 0.0000 pCi/Kg Vegetation 106 12/30/2024 1-131 0.0000 0.0000 18.0760 pCi/Kg Vegetation 106 12/30/2024 Be-7 8151.2000 597.1200 0.0000 pCi/Kg Vegetation 106 12/30/2024 Cs-137 57.2960 18.5470 0.0000 pCi/Kg Vegetation 106 12/30/2024 Cs-134 0.0000 0.0000 14.2510 pCi/Kg Vegetation 112 1/29/2024 1-131 0.0000 0.0000 36.2350 pCi/Kg Vegetation 112 1/29/2024 Cs-134 0.0000 0.0000 32.4790 pCi/Kg Vegetation 112 1/29/2024 Cs-137 0.0000 0.0000 20.8300 pCi/Kg Vegetation 112 1/29/2024 Be-7 3981.0000 492.3400 0.0000 pCi/Kg Vegetation 112 2/26/2024 Cs-137 0.0000 0.0000 5.8133 pCi/Kg Vegetation 112 2/26/2024 Be-7 997.0600 122.1400 0.0000 pCi/Kg Vegetation 112 2/26/2024 1-131 0.0000 0.0000 6.5992 pCi/Kg Vegetation 112 2/26/2024 Cs-134 0.0000 0.0000 5.8159 pCi/Kg Vegetation 112 3/25/2024 Be-7 2691.1000 298.0000 0.0000 pCi/Kg Vegetation 112 3/25/2024 Cs-134 0.0000 0.0000 17.9680 pCi/Kg Vegetation 112 3/25/2024 1-131 0.0000 0.0000 17.3100 pCi/Kg Vegetation 112 3/25/2024 Cs-137 0.0000 0.0000 12.7080 pCi/Kg Vegetation 112 4/29/2024 Be-7 3104.8000 345.5300 0.0000 pCi/Kg Vegetation 112 4/29/2024 Cs-137 0.0000 0.0000 15.8530 pCi/Kg Vegetation 112 4/29/2024 Cs-134 0.0000 0.0000 16.7590 pCi/Kg Vegetation 112 4/29/2024 1-131 0.0000 0.0000 19.1580 pCi/Kg Vegetation 112 5/28/2024 1-131 0.0000 0.0000 11.5960 pCi/Kg Vegetation 112 5/28/2024 Cs-134 0.0000 0.0000 8.5402 pCi/Kg Vegetation 112 5/28/2024 Cs-137 15.0530 7.7769 0.0000 pCi/Kg Vegetation 112 5/28/2024 Be-7 1125.4000 142.1200 0.0000 pCi/Kg

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 83 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Vegetation 112 6/24/2024 1-131 0.0000 0.0000 27.2120 pCi/Kg Vegetation 112 6/24/2024 Cs-134 0.0000 0.0000 27.5430 pCi/Kg Vegetation 112 6/24/2024 Cs-137 0.0000 0.0000 24.2960 pCi/Kg Vegetation 112 6/24/2024 Be-7 1536.2000 294.9300 0.0000 pCi/Kg Vegetation 112 7/29/2024 Cs-134 0.0000 0.0000 14.8260 pCi/Kg Vegetation 112 7/29/2024 1-131 0.0000 0.0000 14.4450 pCi/Kg Vegetation 112 7/29/2024 Be-7 1579.7000 211.6600 0.0000 pCi/Kg Vegetation 112 7/29/2024 Cs-137 0.0000 0.0000 12.0920 pCi/Kg Vegetation 112 8/26/2024 Be-7 1391.2000 247.3700 0.0000 pCi/Kg Vegetation 112 8/26/2024 Cs-137 0.0000 0.0000 17.7460 pCi/Kg Vegetation 112 8/26/2024 Cs-134 0.0000 0.0000 15.6800 pCi/Kg Vegetation 112 8/26/2024 1-131 0.0000 0.0000 20.1050 pCi/Kg Vegetation 112 10/1/2024 Cs-134 0.0000 0.0000 16.8600 pCi/Kg Vegetation 112 10/1/2024 Cs-137 0.0000 0.0000 16.8820 pCi/Kg Vegetation 112 10/1/2024 Be-7 3421.0000 384.2900 0.0000 pCi/Kg Vegetation 112 10/1/2024 1-131 0.0000 0.0000 19.8080 pCi/Kg Vegetation 112 10/28/2024 Cs-137 0.0000 0.0000 14.1960 pCi/Kg Vegetation 112 10/28/2024 Be-7 2895.1470 333.6740 0.0000 pCi/Kg Vegetation 112 10/28/2024 Cs-134 0.0000 0.0000 12.8280 pCi/Kg Vegetation 112 10/28/2024 1-131 0.0000 0.0000 30.9240 pCi/Kg Vegetation 112 11/25/2024 1-131 0.0000 0.0000 32.9820 pCi/Kg Vegetation 112 11/25/2024 Cs-134 0.0000 0.0000 17.3270 pCi/Kg Vegetation 112 11/25/2024 Cs-137 0.0000 0.0000 18.9330 pCi/Kg Vegetation 112 11/25/2024 Be-7 681.9500 393.2700 0.0000 pCi/Kg Vegetation 112 12/30/2024 1-131 0.0000 0.0000 11.2450 pCi/Kg Vegetation 112 12/30/2024 Cs-134 0.0000 0.0000 9.6084 pCi/Kg Vegetation 112 12/30/2024 Cs-137 0.0000 0.0000 9.5374 pCi/Kg Vegetation 112 12/30/2024 Be-7 2856.8000 253.2800 0.0000 pCi/Kg Vegetation 416 1/29/2024 Be-7 9062.5000 783.2700 0.0000 pCi/Kg

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 84 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Vegetation 416 1/29/2024 Cs-137 0.0000 0.0000 15.8920 pCi/Kg Vegetation 416 1/29/2024 Cs-134 0.0000 0.0000 18.7060 pCi/Kg Vegetation 416 1/29/2024 1-131 0.0000 0.0000 16.4950 pCi/Kg Vegetation 416 3/25/2024 Be-7 2961.9000 271.9000 0.0000 pCi/Kg Vegetation 416 3/25/2024 Cs-137 0.0000 0.0000 7.7266 pCi/Kg Vegetation 416 3/25/2024 Cs-134 0.0000 0.0000 9.1272 pCi/Kg Vegetation 416 3/25/2024 1-131 0.0000 0.0000 13.3160 pCi/Kg Vegetation 416 4/29/2024 1-131 0.0000 0.0000 7.5865 pCi/Kg Vegetation 416 4/29/2024 Cs-134 0.0000 0.0000 6.2875 pCi/Kg Vegetation 416 4/29/2024 Cs-137 0.0000 0.0000 6.7842 pCi/Kg Vegetation 416 4/29/2024 Be-7 1413.1000 150.0700 0.0000 pCi/Kg Vegetation 416 5/28/2024 Be-7 1229.6000 139.8200 0.0000 pCi/Kg Vegetation 416 5/28/2024 Cs-137 0.0000 0.0000 6.2804 pCi/Kg Vegetation 416 5/28/2024 Cs-134 0.0000 0.0000 12.5680 pCi/Kg Vegetation 416 5/28/2024 1-131 0.0000 0.0000 11.5210 pCi/Kg Vegetation 416 6/24/2024 Be-7 5196.5000 471.0900 0.0000 pCi/Kg Vegetation 416 6/24/2024 Cs-137 0.0000 0.0000 15.1850 pCi/Kg Vegetation 416 6/24/2024 Cs-134 0.0000 0.0000 15.7730 pCi/Kg Vegetation 416 6/24/2024 1-131 0.0000 0.0000 16.3580 pCi/Kg Vegetation 416 7/29/2024 Be-7 1580.7000 171.4200 0.0000 pCi/Kg Vegetation 416 7/29/2024 Cs-137 0.0000 0.0000 6.9872 pCi/Kg Vegetation 416 7/29/2024 Cs-134 0.0000 0.0000 11.7900 pCi/Kg Vegetation 416 7/29/2024 1-131 0.0000 0.0000 11.9770 pCi/Kg Vegetation 416 8/26/2024 Be-7 1557.2000 207.8900 0.0000 pCi/Kg Vegetation 416 8/26/2024 Cs-137 0.0000 0.0000 11.7000 pCi/Kg Vegetation 416 8/26/2024 Cs-134 0.0000 0.0000 12.3940 pCi/Kg Vegetation 416 8/26/2024 1-131 0.0000 0.0000 14.9170 pCi/Kg Vegetation 416 10/1/2024 Be-7 2385.9000 254.9300 0.0000 pCi/Kg Vegetation 416 10/1/2024 Cs-137 0.0000 0.0000 10.8410 pCi/Kg

Annual Radiological Environmental Operating Report I YEAR: 2024 I

Page 85 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Complete Data Table for All Analysis Results Obtained In 2024 Sample Type Location Date Nuclide Activity 95% CL MDA Units Vegetation 416 10/1/2024 Cs-134 0.0000 0.0000 10.4020 pCi/Kg Vegetation 416 10/1/2024 1-131 0.0000 0.0000 11.3480 pCi/Kg Vegetation 416 10/28/2024 1-131 0.0000 0.0000 14.4330 pCi/Kg Vegetation 416 10/28/2024 Cs-134 0.0000 0.0000 11.9690 pCi/Kg Vegetation 416 10/28/2024 Cs-137 0.0000 0.0000 13.0890 pCi/Kg Vegetation 416 10/28/2024 Be-7 1520.8000 196.6500 0.0000 pCi/Kg Vegetation 416 11/25/2024 Be-7 1756.0000 214.8400 0.0000 pCi/Kg Vegetation 416 11/25/2024 Cs-137 0.0000 0.0000 11.4310 pCi/Kg Vegetation 416 11/25/2024 Cs-134 0.0000 0.0000 10.8940 pCi/Kg Vegetation 416 11/25/2024 1-131 0.0000 0.0000 19.2380 pCi/Kg Vegetation 416 12/30/2024 1-131 0.0000 0.0000 25.6350 pCi/Kg Vegetation 416 12/30/2024 Cs-134 0.0000 0.0000 20.1400 pCi/Kg Vegetation 416 12/30/2024 Cs-137 0.0000 0.0000 21.3150 pCi/Kg Vegetation 416 12/30/2024 Be-7 7292.9000 692.6700 0.0000 pCi/Kg

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 86 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Cross Check lntercomparison Program

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 87 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Cross Check lntercomparison Program Participation in cross check intercomparison studies is mandatory for laboratories performing analyses of REMP samples satisfying the requirements in the Offsite Site Dose Calculation Manual. lntercomparison studies provide a consistent and effective means to evaluate the accuracy and precision of analyses performed by a laboratory.

Study results should fall within specified control limits and results that fall outside the control limits are investigated and corrected.

Georgia Power Company Environmental Lab participated in the following proficiency testing studies provided by Eckert Ziegler Analytics, Inc. in 2024. The Laboratory's intercomparison program results for 2024 are summarized below.

Cross Check I ntercomparison Results Radionuclide/Standard Units Reported Assigned Acceptance Performance Value Value Limits Evaluation Air Filter Mixed Gamma Ce-141 pCi 73.3 69.7 0.80-1.25 1.05 Co-58 pCi 89.4 84.2 0.80-1.25 1.06 Co-60 pCi 136 133 0.80-1.25 1.02 Cr-51 pCi 165 154 0.80-1.25 1.07 Cs-134 pCi 110 105 0.80-1.25 1.04 Cs-137 pCi 78.9 71.7 0.80-1.25 1.10 Fe-59 pCi 68.0 63.9 0.80-1.25 1.06 Mn-54 pCi 102 91.0 0.80-1.25 1.12 Zn-65 pCi 173 155 0.80-1.25 1.12 Air Filter Gross Alpha/Beta Gross Alpha pCi 203 198 0.80-1.25 1.03 Gross Beta pCi 85.0 91.7 0.80-1.25 0.93 Water Mixed Gamma Ce-141 pCi/L 39.9 37.5 0.80-1.25 1.06 Co-58 pCi/L 0.0 Not Measured 0.80-1.25 NA Co-60 pCi/L 374 391 0.80-1.25 0.96 Cr-51 pCi/L 288 291 0.80-1.25 0.99 Cs-134 pCi/L 234 242 0.80-1.25 0.97 Cs-137 pCi/L 231 229 0.80-1.25 1.01 Fe-59 pCi/L 170 174 0.80-1.25 0.98 1-131 pCi/L 182 185 0.80-1.25 0.98 Mn-54 pCi/L 212 204 0.80-1.25 1.04 Zn-65 pCi/L 107 99.1 0.80-1.25 1.08

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 88 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Cross Check lntercomparison Program Cross Check I ntercomparison Results Radionuclide/Standard Units Reported Assigned Acceptance Performance Value Value Limits Evaluation Water Gross Alpha/Beta Gross Alpha pCi/L 116 112 0.80-1.25 1.04 Gross Beta pCi/L 335 292 0.80-1.25 1.15 Water Tritium H-3 pCi/L 13700 14500 0.80-1.25 0.94 Charcoal 1-131 pCi 92.4 91.5 0.80-1.25 1.01 Milk Mixed Gamma Ce-141 pCi/L 126 124 0.80-1.25 1.02 Co-58 pCi/L 152 150 0.80-1.25 1.02 Co-60 pCi/L 234 236 0.80-1.25 0.99 Cr-51 pCi/L 279 274 0.80-1.25 1.02 Cs-134 pCi/L 185 187 0.80-1.25 0.99 Cs-137 pCi/L 133 127 0.80-1.25 1.04 Fe-59 pCi/L 111 113 0.80-1.25 0.98 1-131 pCi/L 88.6 89.0 0.80-1.25 1.00 Mn-54 pCi/L 172 162 0.80-1.25 1.06 Zn-65 pCi/L 292 275 0.80-1.25 1.06 Vegetation Mixed Gamma Ce-141 pCi/g 0.234 0.226 0.80-1.25 1.04 Co-58 pCi/g 0.265 0.272 0.80-1.25 0.97 Co-60 pCi/g 0.414 0.429 0.80-1.25 0.96 Cr-51 pCi/g 0.507 0.499 0.80-1.25 1.02 Cs-134 pCi/g 0.321 0.341 0.80-1.25 0.94 Cs-137 pCi/g 0.232 0.232 0.80-1.25 1.00 Fe-59 pCi/g 0.203 0.207 0.80-1.25 0.98 Mn-54 pCi/g 0.302 0.294 0.80-1.25 1.03 Zn-65 pCi/g 0.496 0.501 0.80-1.25 0.99

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 89 of 91 Company: Southern Nuclear I Plant:

Hatch Nuclear Plant, Environmental Direct Radiation Dosimetry Sample Results

Quarterly Monitoring

Baseline, Location BQ (mrem)

H064 14.7 H101 14.8 H102 15 H103 14.8 H104 18.1 H105 17.1 H106 14.2 H107 13.4 H108 13.7 H109 15.2 H110 16.1 H111 13.8 H112 13.8 H113 16.5 H114 15.5 H115 21.3 H116 13.2 H201 15.6 H202 14.5 H203 18.7 H204 16.1 Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 90 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant BQ+

MDDQ 19.7 19.8 20.0 19.8 23.1 22.1 19.2 18.4 18.7 20.2 21.1 18.8 18.8 21.5 20.5 26.3 18.2 20.6 19.5 23.7 21.1, Environmental Direct Radiation Dosimetry Sample Results 2024 Environmental Direct Radiation Dosimetry Sample Results Normalized Quarterly Monitoring Data, MQ Quarterly Facility Dose, FQ=MQ-BQ (mrem)

(mrem) 1 2

3 4

1 2

3 4

16.5 17.5 15.0 16.3 ND ND ND ND 15.1 15.0 13.7 ND ND ND 14.9 16.8 12.6 16.3 ND ND ND ND 15.5 17.6 13.9 16.7 ND ND ND ND 16.4 21.0 16.1 19.8 ND ND ND ND 17.6 20.5 15.2 19.6 ND ND ND ND 16.4 15.5 12.7 16.2 ND ND ND ND 15.5 16.1 13.2 15.9 ND ND ND ND 15.4 15.5 12.5 15.5 ND ND ND ND 17.2 16.4 14.1 17.3 ND ND ND ND 16.6 17.8 13.9 17.0 ND ND ND ND 15.9 18.2 12.4 14.6 ND ND ND ND 15.1 15.9 13.2 14.8 ND ND ND ND 17.7 18.1 14.2 16.8 ND ND ND ND 15.7 17.4 13.6 16.4 ND ND ND ND 19.8 23.3 19.9 20.9 ND ND ND ND 13.9 15.8 12.8 14.3 ND ND ND ND 16.7 16.8 13.3 16.4 ND ND ND ND 15.6 15.8 14.3 14.9 ND ND ND ND 18.9 20.7 18.0 ND ND ND 16.8 19.8 14.0 16.7 ND ND ND ND Annual

Baseline, BA+

BA MDDA (mrem) 59.0 69.4 59.1 69.5 59.9 70.3 59.3 69.7 72.5 82.9 68.4 78.8 56.8 67.2 53.8 64.2 54.8 65.2 60.9 71.3 64.5 74.9 55.1 65.5 55.1 65.5 66.2 76.6 62.2 72.6 85.0 95.4 53.0 63.4 62.2 72.6 57.8 68.2 74.9 85.3 64.4 74.8 Annual Annual Facility Monitoring Data, MA

Dose, (mrem)

FA=MA-BA (mrem) 65.3 ND 43.8 ND 60.6 ND 63.8 ND 73.3 ND 72.9 ND 60.8 ND 60.7 ND 58.9 ND 65.0 ND 65.2 ND 61.0 ND 59.0 ND 66.8 ND 63.1 ND 83.9 ND 56.7 ND 63.2 ND 60.7 ND 57.6 ND 67.4 ND

Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 91 of 91 Company: Southern Nuclear I Plant: Hatch Nuclear Plant, Environmental Direct Radiation Dosimetry Sample Results 2024 Environmental Direct Radiation Dosimetry Sample Results Normalized Quarterly Monitoring Data, MQ Quarterly Facility Dose, FQ=MQ-BQ Quarterly Monitoring

Baseline, BQ+

(mrem)

Location BQ MDDQ (mrem) 1 2

3 4

1 2

3 4

H205 15.8 20.8 16.4 18.2 13.6 18.0 ND ND ND ND H206 13.9 18.9 15.1 15.6 13.1 15.2 ND ND ND ND H207 12.4 17.4 14.0 15.2 11.5 15.0 ND ND ND ND H208 13.4 18.4 14.3 14.6 11.8 14.6 ND ND ND ND H209 13.4 18.4 14.3 15.1 11.2 14.7 ND ND ND ND H210 12.6 17.6 12.0 15.2 11.3 14.3 ND ND ND ND H211 14.4 19.4 16.4 17.9 13.4 15.5 ND ND ND ND H212 14.3 19.3 16.1 18.2 13.1 16.3 ND ND ND ND H213 14.9 19.9 15.3 17.5 14.2 16.9 ND ND ND ND H214 19.4 24.4 18.8 21.2 16.6 19.2 ND ND ND ND H215 18.6 23.6 20.6 20.8 16.7 21.4 ND ND ND ND H216 14.9 19.9 17.6 17.7 13.4 16.5 ND ND ND ND H301 14.9 19.9 16.1 17.1 14.6 18.0 ND ND ND ND H304 15.3 20.3 15.8 17.9 15.3 17.9 ND ND ND ND H309 14 19.0 15.7 17.3 12.4 15.9 ND ND ND ND H416 15.9 20.9 15.5 17.8 14.1 17.8 ND ND ND ND MDDo = Quarterly Minimum Differential Dose = 5 mrem MDDA = Annual Minimum Differential Dose = 10 mrem ND = Not Detected, where Mo s; (Bo+MDDo) or MA s; (BA+MDDA)

Annual

Baseline, BA+

BA MDDA (mrem) 63.2 73.6 55.6 66.0 49.7 60.1 54.0 64.4 53.8 64.2 50.5 60.9 57.7 68.1 57.3 67.7 59.6 70.0 77.4 87.8 74.5 84.9 59.7 70.1 59.5 69.9 61.4 71.8 55.8 66.2 63.8 74.2 Annual Monitoring Data, MA (mrem) 66.3 59.1 55.8 55.4 55.2 52.9 63.3 63.8 63.9 75.8 79.6 65.2 65.8 66.8 61.4 65.3 Blanks in the Normalized Quarterly MonitorinQ Data columns are due to OSLO deviations and anomalies. For more information, see Table 9, Sample Deviation Summary.

Annual Facility

Dose, FA=MA-BA (mrem)

ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND

NL-25-0181, Annual Radiological Environmental Operating Reports for 2024

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SUMMARY

Conclusions:

3.0 INTRODUCTION

SUMMARY

Conclusions:

3.0 INTRODUCTION

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NL-25-0181, Annual Radiological Environmental Operating Reports for 2024

Text

Enclosure:

SUMMARY

Conclusions:

3.0 INTRODUCTION

SUMMARY

Conclusions:

3.0 INTRODUCTION

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