ML25135A067
| ML25135A067 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 05/14/2025 |
| From: | Constellation Energy Generation |
| To: | Office of Nuclear Material Safety and Safeguards, Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML25135A065 | List: |
| References | |
| SVPLTR 25-0033 | |
| Download: ML25135A067 (1) | |
Text
Annual Radiological Environmental Operating Report YEAR: 2024 Page 0 of 76 Company: Constellation Plant: Dresden Clean Energy Center 2024 Docket Number: 50-010, 50-237, 50-249 Annual Radiological Environmental Operating Report
Annual Radiological Environmental Operating Report YEAR: 2024 Page 1 of 76 Company: Constellation Plant: Dresden Clean Energy Center TABLE OF CONTENTS 1.0 LIST OF ACRONYMS AND DEFINITIONS................................................................................ 3 2.0 EXECUTIVE
SUMMARY
............................................................................................................ 4 2.1 Summary of
Conclusions:
............................................................................................... 5
3.0 INTRODUCTION
........................................................................................................................ 6 4.0 SITE DESCRIPTION AND SAMPLE LOCATIONS..................................................................... 7 5.0 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM REQUIREMENTS................ 8 6.0 MAPS OF COLLECTION SITES.............................................................................................. 14 7.0 REPORTING LEVELS FOR RADIOACTIVITY CONCENTRATIONS IN ENVIRONMENTAL SAMPLES................................................................................................. 19 8.0 SAMPLING PROGRAM, PROGRAM MODIFICATION AND INTEPRETATION OF RESULTS................................................................................................................................ 20 8.1 Environmental Direct Radiation Dosimetry Results....................................................... 20 8.2 Air Particulate and Radioiodine Sample Results........................................................... 22 8.3 Waterborne Sample Results......................................................................................... 23 8.4 Ingestion Pathway Sample Results............................................................................... 24 9.0 LAND USE CENSUS............................................................................................................... 26 10.0 DEVIATIONS, ANOMALIES AND UNAVAILABILITY............................................................... 28 11.0 OTHER SUPPLEMENTAL INFORMATION............................................................................. 30 11.1 NEI 07-07 Onsite Radiological Groundwater Monitoring Program................................. 30 11.2 Corrections to Previous Reports................................................................................... 30 12.0 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....................... 19 Table 7, Maximum Values for the Limit of Detection............................................................................ 19 Table 8: Land Use Census - Nearest Receptors within 11.4 miles...................................................... 27 Table 9: Sample Deviation Summary................................................................................................... 29 Table 10: Dresden Station Data Summary Table................................................................................. 33 Table 11, Weekly Air Particulate Gross Beta (E-3 pCi/m3).................................................................... 38 Table 12, Quarterly Air Particulate Gamma Isotopic (pCi/m3 +/- 2 Sigma)............................................... 44 Table 13, Weekly Air Iodine I-131 (E-3 pCi/m3)..................................................................................... 48 Table 14, Monthly/Bi-Weekly Milk I-131 (pCi/L +/- 2 Sigma).................................................................. 54 Table 15, Monthly/Bi-Weekly Milk Gamma Isotopic (pCi/L +/- 2 Sigma)................................................. 54 Table 16, Annual Vegetation Gamma Isotopic (pCi/kg Wet +/- 2 Sigma)................................................ 55 Table 17, Monthly Surface Water Gross Beta (pCi/L +/- 2 Sigma).......................................................... 59 Table 18, Monthly Surface Water Gamma Isotopic (pCi/L +/- 2 Sigma).................................................. 60
Annual Radiological Environmental Operating Report YEAR: 2024 Page 2 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 19, Quarterly Surface Water Tritium (pCi/L +/- 2 Sigma).............................................................. 62 Table 20, Quarterly Ground Water Tritium (pCi/L +/- 2 Sigma).............................................................. 63 Table 21, Quarterly Ground Water Gamma Isotopic (pCi/L +/- 2 Sigma)................................................ 63 Table 22, Semi-Annual Fish Gamma Isotopic (pCi/kg Wet +/- 2 Sigma)................................................. 64 Table 23, Semi-Annual Shoreline Sediment Gamma Isotopic (pCi/kg Dry +/- 2 Sigma)......................... 65 Table 24: Analytics Environmental Radioactivity Cross Check Program.............................................. 69 Table 25: DOEs Mixed Analyte Performance Evaluation Program (MAPEP)...................................... 71 Table 26: ERA Environmental Radioactivity Cross Check Program..................................................... 73 FIGURES Figure 1, Potential exposure pathways to Members of the Public due to Plant Operations [7]............... 6 Figure 2, Dresden Station Inner Ring OSLD Locations, 2024.............................................................. 14 Figure 3, Dresden Station Fixed Air Sampling and OSLD Sites, Outer Ring OSLD Locations, 2024.... 15 Figure 4, Dresden Station Goat Milk Sample Location, 2024 16 Figure 5, Dresden Station Water, Sediment, and Fish Sampling Locations, 2024................................ 17 Figure 6, Dresden Station Broadleaf Vegetation Sampling Locations, 2024......................................... 18 Figure 7, Air Particulate: Analysis for Gross Beta, Average for All Indicator vs. Control Location......... 22 Figure 8: Surface Water Tritium Results.............................................................................................. 23 ATTACHMENTS, Data Table Summary.................................................................................................... 33, Complete Data Table for All Analysis Results Obtained In 2024................................... 38, Cross Check Intercomparison Program......................................................................... 66, Environmental Direct Radiation Dosimetry Results....................................................... 74
Annual Radiological Environmental Operating Report YEAR: 2024 Page 3 of 76 Company: Constellation Plant: Dresden Clean Energy Center 1.0 LIST OF ACRONYMS AND DEFINITIONS
- 1.
Airborne Activity Sampling: Continuous sampling of air through the collection of particulates and radionuclides on filter media.
- 2.
ARERR: Annual Radioactive Effluent Release Report
- 3.
AREOR: Annual Radiological Environmental Operating Report
- 4.
BWR: Boiling Water Reactor
- 5.
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 the composite period.
- 6.
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.
- 7.
Curie (Ci): A measure of radioactivity; equal to 3.7 x 1010 disintegrations per second, or 2.22 x 1012 disintegrations per minute.
- 8.
Direct Radiation Monitoring: The measurement of radiation dose at various distances from the plant is assessed using Thermoluminescent Dosimeters (TLD), Optically Stimulated Luminescence Dosimeters (OSLD) and pressurized ionization chambers.
- 9.
EPA: Environmental Protection Agency
- 10.
GPI: Groundwater Protection Initiative
- 11.
Grab Sample: A single discrete sample drawn at one point in time.
- 12.
Indicator: A sampling location that is likely to be affected by plant effluents due to its proximity and/or direction from the plant.
- 13.
Ingestion Pathway: The ingestion pathway includes milk, fish, drinking water and garden produce. Also sampled (under special circumstances) are other media such as vegetation or animal products when additional information about particular radionuclides is needed.
- 14.
ISFSI: Independent Spent Fuel Storage Installation
- 15.
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.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 4 of 76 Company: Constellation Plant: Dresden Clean Energy Center
- 16.
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.
- 17.
MDC: Minimum Detectable Concentration. Essentially synonymous with MDA for the purposes of radiological monitoring.
- 18.
Mean: The sum of all of the values in a distribution divided by the number of values in the distribution, synonymous with average.
- 19.
Microcurie: 3.7 x 104 disintegrations per second, or 2.22 x106 disintegrations per minute.
- 20.
N/A: Not Applicable
- 21.
NEI: Nuclear Energy Institute
- 22.
NIST: National Institute of Standards and Technology.
- 23.
NRC: Nuclear Regulatory Commission
- 24.
ODCM: Offsite Dose Calculation Manual
- 25.
OSLD: Optically Stimulated Luminescence Dosimeter
- 26.
pCi/L: picocuries / Liter
- 27.
PWR: Pressurized Water Reactor
- 28.
REMP: Radiological Environmental Monitoring Program
- 29.
TLD: Thermoluminescent Dosimeter 2.0 EXECUTIVE
SUMMARY
Dresden Clean Energy Center 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 Dresden Station 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 specifications detailed in 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.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 5 of 76 Company: Constellation Plant: Dresden Clean Energy Center The Annual Radiological Environmental Operating Report (AREOR) provides data obtained through analyses of environmental samples collected at Dresden Station for the reporting period of January 1st through December 31st, 2024. During that time period 1,872 analyses were performed on 1,751 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 Dresden Station, 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 Dresden Station. 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 naturally 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-7, 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 YEAR: 2024 Page 6 of 76 Company: Constellation Plant: Dresden Clean Energy Center
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].
Figure 1, Potential exposure pathways to Members of the Public due to Plant Operations [7]
Quality assurance aspects of the sampling program and TLD/OSLD data collection are conducted in accordance with Regulatory Guides 4.15 [8] and 4.13 [9]. REMP also adheres to the requirements of the State of Illinois, Dresden Station 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.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 7 of 76 Company: Constellation Plant: Dresden Clean Energy Center 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.
4.0 SITE DESCRIPTION AND SAMPLE LOCATIONS The Dresden Nuclear Power Station (DNPS), consisting of one retired reactor and two operating boiling water reactors owned and operated by Constellation Energy Corporation, is located in Grundy County, Illinois. Unit No. 1 went critical in 1960 and was retired in 1978. Unit No. 2 went critical on 16 June 1970. Unit No. 3 went critical on 02 November 1971. The site is located in Northern Illinois, approximately 12 miles southwest of Joliet, Illinois at the confluence of the Des Plaines and Kankakee Rivers where they form the Illinois River.
Dresden Station 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, Dresden Station Inner Ring OSLD Locations, 2024 Figure 3, Dresden Station Fixed Air Sampling and OSLD Sites, Outer Ring OSLD Locations, 2024
Annual Radiological Environmental Operating Report YEAR: 2024 Page 8 of 76 Company: Constellation Plant: Dresden Clean Energy Center 5.0 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM REQUIREMENTS Table 1, Radiological Environmental Sampling Program - Exposure Pathway - Direct Radiation Requirement Sample Location Description, Distance, and Direction Sampling Collection/
Frequency Type and Frequency of Analyses Direct Radiation 46 OSLD monitoring stations with two dosimeters placed as follows:
An inner ring of stations, one in each compass sector in the general area of the site boundary.
An outer ring of stations, one in each compass sector at approximately 5 miles from the site An other set located at the thirteen fixed air sampling locations A control location See Table 5 Quarterly Gamma dose Quarterly
Annual Radiological Environmental Operating Report YEAR: 2024 Page 9 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 2, Radiological Environmental Sampling Program - Exposure Pathway - Airborne Requirement Sample Location Description, Distance, and Direction Sampling Collection/
Frequency Type and Frequency of Analyses Airborne Radioiodine and Particulates Samples from 14 locations:
Nine locations close to the site boundary in different sectors of the highest calculated annual average ground level relative deposition factor (D/Q).
Four samples from the vicinity of a community having the highest calculated annual average D/Q.
One sample from a Control Location between 6.2 - 18.6 miles away in the least predominant wind direction.
D-01 Onsite Station 1, 0.8 miles NW D-02 Onsite Station 2, 0.3 miles NNE D-03 Onsite Station 3, 0.4 miles D-04 Collins Road, on Station, 0.8 miles W D-07 Clay Products, Dresden Road, 2.6 miles S D-08 Jugtown Road, Prairie Parks, 3.8 miles SW D-10 Goose Lake Road, Goose Lake Village, 3.5 miles SSW D-12 Quarry Road, Lisbon(C), 10.5 miles NW D-14 Center Street, Channahon,3.7 miles NE D-45 McKinley Woods Road, Channahon, 1.7 miles ENE D-53 Will Road, Hollyhock, 2.1 miles SSE D-55 Ridge Road, Minooka, 4.3 miles N D-56 Will Road, Wildfeather, 1.7 miles SE D-58 Will Road, Marina, 1.1 miles ESE One-week of continuous air sampling through glass fiber filter paper One week composite of continuous air sampling through charcoal filter Particulate sampler: Gross Beta analysis following weekly filter change and Gamma isotopic quarterly on composite filters by location on near field and control samples.
Radioiodine canister: I-131 analysis weekly on near field and control samples.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 10 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 3, Radiological Environmental Sampling Program - Exposure Pathway - Waterborne Requirement Sample Location Description, Distance, and Direction Sampling Collection/
Frequency Type and Frequency of Analyses Surface Water Two samples upstream (control) and one sample downstream D-21 Illinois River at EJ&E Bridge, D-52 DesPlaines River at Will Road, Upstream(C),
D-57 Kankakee River at Will Road(C),
Monthly composite sample or monthly composite from weekly grab samples.
Quarterly composite of monthly composite samples Gamma isotopic Monthly Gross beta Monthly H-3 Quarterly Groundwater/Well Water Three indicator locations down gradient from the plant, only if likely to be affected.
D-22 8150 N. Thorsen Rd, IL, 0.8 miles SSE D-35 Dresden Lock & Dam Morris, IL, 0.8 miles NW D-39 3985 Will Rd., Coal City, IL, 3.2 miles SSE Quarterly grab samples Gamma isotopic Quarterly H-3 Quarterly Sediment from Shoreline One sample downstream (indicator)
D-27 Illinois River at Dresden Lock and Dam, Downstream, 0.8 miles NW Semiannual grab samples Gamma isotopic Semiannually
Annual Radiological Environmental Operating Report YEAR: 2024 Page 11 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 4, Radiological Environmental Sampling Program - Exposure Pathway - Ingestion Requirement Sample Location Description, Distance, and Direction Sampling Collection/
Frequency Type and Frequency of Analyses Goat Milk Sample from milking animal from a maximum of three locations within 5km (3.1 miles) distance.
D-60* 8270 Duck Pond Road, Coal City, IL. 60416, 4.2 miles S Semimonthly when animals are on pasture (May through October),
monthly at other times (November through April)
Gamma isotopic and I-131 analysis on each sample Fish One sample upstream and one sample downstream of each commercially and recreationally important species in vicinity of site discharge.
D-28 Dresden Pool of Illinois River, Downstream, 0.9 miles NNW D-46 DesPlaines River, Upstream (C), 1.2 miles ESE Samples collected twice annually via electroshocking or other techniques Gamma isotopic analysis on edible portions Vegetation Five broad leaf vegetation grown nearest each of two different offsite locations of highest predicted annual average ground level D/Q if milk sampling is not performed and one sample collected from the control location.
D-25 Vince Biros Farm, Reed Road(C), 11.3 miles SW D-39* 3985 Will Rd., Coal City, IL, 3.2 miles SSE D-42 Dresden Site Garden, 0.4 miles N D-43 25158 W Elm St, 3.3 miles NE D-44 9980 Ridge Road, 3.0 miles N Grab samples July through September Gamma isotopic on each sample
- These locations are currently not listed in the ODCM but are included as sampling is being done. The ODCM will be updated to include these locations with the appropriate sampling frequency (CA 04780725-02).
Annual Radiological Environmental Operating Report YEAR: 2024 Page 12 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 5, REMP Sampling Locations - Direct Radiation Site #
Location Type Sector Distance Description D-101 Inner Ring N
1.0 miles D-102 Inner Ring NNE 1.4 miles D-103 Inner Ring NE 1.2 miles D-104 Inner Ring ENE 1.7 miles D-105 Inner Ring E
1.5 miles D-106 Inner Ring ESE 1.1 miles D-107 Inner Ring SE 1.4 miles D-108 Inner Ring SSE 1.9 miles D-109 Inner Ring S
0.8 miles D-110 Inner Ring SSW 0.9 miles D-111 Inner Ring SW 0.6 miles D-112 Inner Ring WSW 0.7 miles D-113 Inner Ring W
0.9 miles D-114 Inner Ring WNW 0.9 miles D-115 Inner Ring NW 0.8 miles D-116 Inner Ring NNW 1.0 miles D-201 Outer Ring N
4.8 miles D-202 Outer Ring NNE 5.1 miles D-203 Outer Ring NE 4.7 miles D-204 Outer Ring ENE 5.1 miles D-205 Outer Ring E
4.0 miles D-206 Outer Ring ESE 3.5 miles D-207 Outer Ring SE 4.2 miles
Annual Radiological Environmental Operating Report YEAR: 2024 Page 13 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 5, REMP Sampling Locations - Direct Radiation Site #
Location Type Sector Distance Description D-208 Outer Ring SSE 4.9 miles D-209 Outer Ring S
4.1 miles D-210 Outer Ring SSW 4.9 miles D-211 Outer Ring SW 4.8 miles D-212 Outer Ring WSW 6.0 miles D-213 Outer Ring W
4.6 miles D-214 Outer Ring WNW 5.0 miles D-215 Outer Ring NW 4.8 miles D-216 Outer Ring NNW 4.9 miles D-01 Other NW 0.8 miles Onsite 1 D-02 Other NNE 0.3 miles Onsite 2 D-03 Other S
0.4 miles Onsite 3 D-04 Other W
0.8 miles Collins Road, on Station property D-07 Other S
2.6 miles Clay Products, Dresden Road D-08 Other SW 3.8 miles Jugtown Road, Prairie Parks D-10 Other SSW 3.5 miles Goose Lake Road, Goose Lake Village D-14 Other NE 3.7 miles Center Street, Channahon D-45 Other ENE 1.7 miles McKinley Woods Road, Channahon D-53 Other SSE 2.1 miles Will Road, Hollyhock D-55 Other N
4.3 miles Ridge Road, Minooka D-56 Other SE 1.7 miles Will Road, Wildfeather D-58 Other ESE 1.1 miles Will Road, Marina D-12 Control NW 10.5 miles Lisbon
Annual Radiological Environmental Operating Report YEAR: 2024 Page 14 of 76 Company: Constellation Plant: Dresden Clean Energy Center 6.0 MAPS OF COLLECTION SITES Figure 2, Dresden Station Inner Ring OSLD Locations, 2024 D-115 D-104
Annual Radiological Environmental Operating Report YEAR: 2024 Page 15 of 76 Company: Constellation Plant: Dresden Clean Energy Center Figure 3, Dresden Station Fixed Air Sampling and OSLD Sites, Outer Ring OSLD Locations, 2024
Annual Radiological Environmental Operating Report YEAR: 2024 Page 16 of 76 Company: Constellation Plant: Dresden Clean Energy Center Figure 4, Dresden Goat Milk Sample Location, 2024
Annual Radiological Environmental Operating Report YEAR: 2024 Page 17 of 76 Company: Constellation Plant: Dresden Clean Energy Center Figure 5, Dresden Station Water, Sediment, and Fish Sampling Locations, 2024
Annual Radiological Environmental Operating Report YEAR: 2024 Page 18 of 76 Company: Constellation Plant: Dresden Clean Energy Center Figure 6, Dresden Station Broadleaf Vegetation Sampling Locations, 2024
Annual Radiological Environmental Operating Report YEAR: 2024 Page 19 of 76 Company: Constellation Plant: Dresden Clean Energy Center 7.0 REPORTING LEVELS FOR RADIOACTIVITY CONCENTRATIONS IN ENVIRONMENTAL SAMPLES Table 6, Reporting Levels for Radioactivity Concentrations in Environmental Samples Radionuclide Water (pCi/L)
Air Particulates or Gases (pCi/m3)
Fish (pCi/kg-wet)
Milk (pCi/L)
Food Products (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 I-131 2 (2) 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 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/l 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 40 CFR 141 Safe drinking water ACT.
4 If no drinking water pathway exists, a value of 15 pCi/l may be used Table 7, Maximum Values for the Limit of Detection Radionuclide Water (pCi/L)
Air Particulates or Gases (pCi/m3)
Fish (pCi/kg-wet)
Milk (pCi/L)
Food Products (pCi/Kg-wet)
Sediment (pCi/Kg-dry)
Gross Beta 4
0.01 NA NA NA NA H-3 2,000 (3)
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-95 30 NA NA NA NA NA Nb-95 15 NA NA NA NA NA I-131 1 (4) 0.07 NA 1
60 NA Cs-134 15 0.05 130 15 60 150 Cs-137 18 0.06 150 18 80 180
Annual Radiological Environmental Operating Report YEAR: 2024 Page 20 of 76 Company: Constellation Plant: Dresden Clean Energy Center 8.0 SAMPLING PROGRAM, PROGRAM MODIFICATION AND INTEPRETATION 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 environs 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.
8.1 Environmental Direct Radiation Dosimetry 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.
ANSI/HPS N13.37-2014 uses the concept of minimum differential dose (MDD), which is the minimum facility-related dose that can be detected above background. Due to natural background variations and measurement sensitivities and uncertainties, minimum differential dose is not zero. MDD is calculated based on statistical performance of the dosimetry system in the environment and is site specific.
Normalized 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.
Table 7, Maximum Values for the Limit of Detection Contd Radionuclide Water (pCi/L)
Air Particulates or Gases (pCi/m3)
Fish (pCi/kg-wet)
Milk (pCi/L)
Food Products (pCi/Kg-wet)
Sediment (pCi/Kg-dry)
Ba-140 60 NA NA 60 NA NA La-140 15 NA NA 15 NA NA
Annual Radiological Environmental Operating Report YEAR: 2024 Page 21 of 76 Company: Constellation Plant: Dresden Clean Energy Center During the calendar year 2024, a total of 46 locations were monitored and data., Environmental Direct Radiation Dosimetry Results, provides the annual direct radiation dosimetry analysis.
There was no direct radiation dose detected from the facility. All OSLD measurements were analyzed, and none were found to have radiation levels that had increased over normal background radiation levels.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 22 of 76 Company: Constellation Plant: Dresden Clean Energy Center 8.2 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 the calendar year 2024, a total of 727 samples were collected and analyzed for gross beta, gamma emitters and iodine. Particulate samplers are used to continuously collect airborne particulates on a filter. The samples are analyzed for gross beta activity following filter changeout which occurs weekly. Gamma isotopic analysis is also performed on the samples collected at each location and is analyzed quarterly. Radioiodine (I-131) analysis is performed weekly on radioiodine sample cartridges.
All air particulate and radioiodine samples were below detection limit and all air particulate gamma composite samples were below the detection limit except for naturally occurring radionuclides.
Figure 7, Air Particulate: Analysis for Gross Beta, Average for All Indicator vs. Control Location Air particulate and radioiodine results from this monitoring period, 2024, were compared to a 10-year average as shown in Figure, and there were no significant change.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 23 of 76 Company: Constellation Plant: Dresden Clean Energy Center 8.3 Waterborne Sample Results 8.3.1 Surface Water (i.e., Bay, Lake etc.)
Composite water samples are collected monthly at the upstream control location and at the downstream indicator locations. Monthly composite samples are analyzed for Gross Beta and gamma emitters. Aliquots from the monthly composites are combined to form a quarterly composite which is then analyzed for tritium. During the calendar year 2024, a total of 36 surface 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. Gross Beta was detected in 33 of the 36 samples with a range of 3 to 14 pCi/L. In the 3 samples that were non-detect for gross beta, the required LLD of 4 pCi/L was met. Samples from all locations were analyzed for gamma-emitting nuclides. No gamma-emiting nuclides were detected and all required LLDs were met. Tritium was detected in seven samples with concentrations ranging from 230 to 1780 pCi/L (Table 19, Quarterly Surface Water Tritium (pCi/L +/- 2 Sigma)). Tritium concentrations in surface water were well below the EPA tritium drinking water limit of 20,000 pCi/L and were consistent with expected levels as a result of permitted liquid discharges.
- There are no detected tritium results for D-52(Indicator). If there are detected results in the future, it will be added to the graph for trending.
Figure 8: Surface Water Tritium Results
Annual Radiological Environmental Operating Report YEAR: 2024 Page 24 of 76 Company: Constellation Plant: Dresden Clean Energy Center 8.3.2 REMP Groundwater Groundwater samples were collected from control location upgradient from the plant and indicator location down gradient from the plant. During the calendar year 2024, a total of 12 groundwater water samples were collected from offsite monitoring wells and analyzed in accordance with the requirements in the ODCM and shown in Table 3: Radiological Environmental Sampling Program - Exposure Pathway - Waterborne.
A total of three indicator sample locations were collected. These samples were analyzed for tritium and gamma quarterly. All samples were collected in new unused plastic bottles, which were rinsed with source water prior to collection.
Samples from all locations were analyzed for gamma-emitting nuclides. No nuclides were detected and all required LLDs were met. There has been no detectable tritium in any REMP groundwater samples in 2024 or the previous 10 years, therefore, no trend has been established above the detection limit to plot on a trending graph.
8.3.3 Sediment from Shoreline Shoreline sediment collections were made in May and October, 2024 and analyzed for gamma-emitting isotopes. Samples are collected from an indicator location. A total of 2 shoreline samples were analyzed in accordance with requirements in the ODCM and shown in Table 3, Radiological Environmental Sampling Program - Exposure Pathway - Waterborne.
No nuclides potentially associated with Dresden Station were detected and all required LLDs were met.
8.4 Ingestion Pathway Sample Results 8.4.1 Milk If there are no milk samples within 5 km, samples may be collected from three areas between 5 - 8 km away from plant center, where doses are calculated to be greater than 1 mrem per year. Milk and vegetation samples were collected June-December and were analyzed for gamma-emitting isotopes and Iodine-131(Low Level).
No nuclides potentially associated with Dresden Station were detected and all required LLDs were met.
A new location for milk sample was found in June 2024. Milk samples were collected on a monthly basis, and the results are provided in Attachment 1 below. However, the ODCM manual was not updated to reflect the new sample location. The sample location will be added to the ODCM manual as part of the REMP sampling (CA 04780725-02).
Annual Radiological Environmental Operating Report YEAR: 2024 Page 25 of 76 Company: Constellation Plant: Dresden Clean Energy Center 8.4.2 Fish A total of 8 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.
No nuclides potentially associated with Dresden Station were detected and all required LLDs were met.
8.4.3 Leafy Vegetation In accordance with the ODCM and as described in Table 4, Radiological Environmental Sampling Program - Exposure Pathway - Ingestion, 51 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 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 and Fukushima events.
Two locations mentioned in the ODCM, D-40 and D-41, are no longer being sampled.
The ODCM will be updated to exclude these two locations.
No nuclides potentially associated with Dresden Station were detected and all required LLDs were met.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 26 of 76 Company: Constellation Plant: Dresden Clean Energy Center 9.0 LAND USE CENSUS An annual land use census is required by the Offsite Dose Calculation Manual and 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. The 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 Receptors within 11.4 miles. In summary, the highest D/Q locations for nearest livestock and nearest residence did not change following the 2024 census, while there was a change to the milking animal. An additional location for milking animals was added due to the previous location no longer being able to provide milk.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 27 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 8: Land Use Census - Nearest Receptors within 11.4 miles Sector Direction Nearest Residence Distance (Miles)
Nearest Milk Animal Distance (Miles)
Livestock Distance (Miles)
A N
27141 Basswood Drive, on Ridge Rd.; east side.
1.5 V. Dollinger, Ridge Road, north of Cemetery Rd.
1.4 B
NNE John Orr, Off Hansel Rd. just past Bennitt Rd.;
house on ridge across from station 0.8 C
NE 26618 Kimberly Road; Highland Estates 0.8 D
ENE Lindstrom, 26605 Highland Drive 0.7 McDonald Farm, east side of McKinley Park Rd.; east side of road at D-45 1.7 E
E Ray and Janet Page, 26223 Highland Drive, west on Highland Dr. and off Mckinley Road.
1.1 F
ESE Harold Klinger, 6579 N. Will Road, near Yacht Club and TLD 106 1.1 G
SE McIntosh, 8495 Pheasant Trail, east bank of Kankakee River; on point of land between Des Plaines and Kankakee River 0.6 H
SSE Kenneth McMillian, 8110 Blanchard Court, end of Blanchard Road and Kankakee River; west bank 0.5 J
S Brian Blottiaux, 6450 Dresden Road, corner of Blanchard Ct. and Dresden Rd.
0.5 8270 Duck Pond Road, Coal City, IL. 60416 4.2 K
SSW 6990 Pine Bluff Road, David Grohne-owner; Erickson-resident; north side of Pine Bluff Rd., 1st farm west of Dresden Rd.
3.3
Annual Radiological Environmental Operating Report YEAR: 2024 Page 28 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 8: Land Use Census - Nearest Receptors within 11.4 miles Contd Sector Direction Nearest Residence Distance (Miles)
Nearest Milk Animal Distance (Miles)
Livestock Distance (Miles)
L SW Bill Boarshore, 5240 Pine Bluff Road, east of the corner of Jugtown and Pine Bluff Rd.
3.6 Biros Dairy Farm, Reed Road and Rt.47; east one Reed 1.2 miles; farm on north side of road.
11.4 M
WSW 2605 E. Collins Rd.
5.5 N
W Don Ehret, 4897 Cemetery Road 3.5 Constellation Property, just past Dresden Road 0.5 P
WNW Don Williams, 5480 Commercial Road, near corner of Rt. 6 and Quantum Rd.
3.2 Constellation Property, just past Dresden Road 0.5 Q
NW Dean Briscoe, 6700 Rt. 6, 0.4 miles from McLindon Road 2.2 Constellation Property, just past Dresden Road 0.5 R
NNW 27231 Deer Hollow Ln.
Channahon, IL.
1.5 V. Dollinger, Hansel Road, 0.4 miles west of Ridge Road.
1.0 10.0 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 TLDs/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, Sample Deviation, and Unavailable Samples.
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, TLD).
All required samples were collected and analyzed as scheduled except for the following:
Annual Radiological Environmental Operating Report YEAR: 2024 Page 29 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 9: Sample Deviation Summary Sample Type Location Collection Date or Period Reason for not conducting REMP sampling as required by ODCM Plans for preventing reoccurrence AP/AI D-03 01/05/2024 No power at the location during the whole collection period.
Actions have been assigned to address power failure and missing OSLD.
AP/AI D-03 01/12/2024 No power at the location during the whole collection period.
AP/AI D-12 01/12/2024 Power failure at the station. Sample was too small to collect. Volume was calculated to be 12.1 m3, where typical sample volume is approximately 260-300 m3. Activity calculations involve division of the sample volume therefore, low sample volume causes erroneously high result.
AP/AI D-01 01/19/2024 No power at the station during the whole collection period AP/AI D-03 01/19/2024 No power at the station during the whole collection period AP/AI D-04 01/19/2024 No power at the station during the whole collection period SW D-52 01/19/2024 No sample due to the river being frozen.
AP/AI D-03 01/26/2024 No power at the station during the whole collection period AP/AI D-04 01/26/2024 No power at the station during the whole collection period OSLD D-108-1,2 3rd Quarter 2024 Both OSLDs missing, possibly due to vandalism.
AP/AI D-02 11/15/2024 Pump stopped running after a short circuit.
AP/AI D-53 11/15/2024 Pump found not running due to a power failure.
AP/AI D-02 11/22/2024 No power at the station during the whole collection period AP/AI D-02 11/29/2024 No power at the station during the whole collection period AP/AI D-02 12/06/2024 No power at the station during the whole collection period SW D-52 12/06/2024 No sample due to the river being frozen.
AP/AI D-02 12/13/2024 No power at the station during the whole collection period SW D-52 12/13/2024 No sample due to the river being frozen.
AP/AI D-02 12/20/2024 No power at the station during the whole collection period AP/AI D-02 12/27/2024 No power at the station during the whole collection period
Annual Radiological Environmental Operating Report YEAR: 2024 Page 30 of 76 Company: Constellation Plant: Dresden Clean Energy Center 11.0 OTHER SUPPLEMENTAL INFORMATION 11.1 NEI 07-07 Onsite Radiological Groundwater Monitoring Program Dresden Clean Energy Center 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 in order 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 on-site groundwater monitoring program are separate from the Radiological Environmental Monitoring Program (REMP).
Results of the NEI 07-07 Radiological Groundwater Monitoring Program for onsite groundwater wells are provided in the ARERR.
11.2 Corrections to Previous Reports No corrections made to previous reports in 2024.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 31 of 76 Company: Constellation Plant: Dresden Clean Energy Center 12.0 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.
[10] "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, 1974.
[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 InitiativeFinal Guidance Document,," Nuclear Energy Institute, Washington, D.C..
Annual Radiological Environmental Operating Report YEAR: 2024 Page 32 of 76 Company: Constellation Plant: Dresden Clean Energy Center
[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] "40 CFR 190 - Environmental Radiation Protection Standards for Nuclear Power Operation," US Environmental Protection Agency, Washington, DC.
[24] "NUREG-0324 - XOQDOQ, Program for the Meteorological Evaluation of Routine Effluent Releases at Nuclear Power Stations," Nuclear Regulatory Commission, September, 1977.
[25] "10 CFR 20 - Standards for Protection Against Radiation," US Nuclear Regulatory Commission, Washington, DC.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 33 of 76 Company: Constellation Plant: Dresden Clean Energy Center
, Data Table Summary Table 10: Dresden Station Data Summary Table Medium or Pathway Sampled (Units)
Type, Total Number of Analyses performed (e.g., I-131, 400)
Lower Limit of Detection (LLD)
Indicator Mean5; (f6).
Range5 Location with Highest Annual Mean Control Mean5 (f6).
Range5 Number of Nonroutine Reported Measurements Name Distance and Direction Mean5 (f6)
Range5 Air Particulates (E-03 pCi/m3)
Gross Beta, 727 10 D-12 0
17.9 (673/674)
Lisbon 26.7 (53/53) 26.7 (53/53)
(5.4/59.2) 10.5 miles NW (7.1/503)
(7.1/503)
- Gamma, 56 Mn-54 N/A
< LLD
< LLD
< LLD
< LLD 0
Co-58 N/A
< LLD
< LLD
< LLD
< LLD 0
Fe-59 N/A
< LLD
< LLD
< LLD
< LLD 0
Co-60 N/A
< LLD
< LLD
< LLD
< LLD 0
Zn-65 N/A
< LLD
< LLD
< LLD
< LLD 0
Nb-95 N/A
< LLD
< LLD
< LLD
< LLD 0
Zr-95 N/A
< LLD
< LLD
< LLD
< LLD 0
I-131 N/A
< LLD
< LLD
< LLD
< LLD 0
Cs-134 50
< LLD
< LLD
< LLD
< LLD 0
Cs-137 60
< LLD
< LLD
< LLD
< LLD 0
Ba-140 N/A
< LLD
< LLD
< LLD
< LLD 0
La-140 N/A
< LLD
< LLD
< LLD
< LLD 0
Airborne Radioiodine (E-03 pCi/m3)
Gamma, 727 I-131 70
< LLD
< LLD
< LLD N/A 0
Direct Radiation (mrem/qtr.)
Gamma Dose, 183 N/A 20.5 D-110 25.1 20.3 0
(179/179) 0.9 miles SSW (4/4)
(4/4)
(13.2/29.9)
(23/29.9)
(17/23.7) 5 Mean and range are based on detectable measurements only.
6 Fraction are based on detectable measurements at specified locations is indicated in parentheses.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 34 of 76 Company: Constellation Plant: Dresden Clean Energy Center
, Data Table Summary Table 10: Dresden Station Data Summary Table Medium or Pathway Sampled (Units)
Type, Total Number of Analyses performed (e.g., I-131, 400)
Lower Limit of Detection (LLD)
Indicator Mean5; (f6).
Range5 Location with Highest Annual Mean Control Mean5 (f6).
Range5 Number of Nonroutine Reported Measurements Name Distance and Direction Mean5 (f6)
Range5 Goat Milk (pCi/L)
I-131 (Low Level), 5 1
< LLD
< LLD
< LLD N/A 0
Gamma, 5 Mn-54 N/A
< LLD
< LLD
< LLD N/A 0
Co-58 N/A
< LLD
< LLD
< LLD N/A 0
Fe-59 N/A
< LLD
< LLD
< LLD N/A 0
Co-60 N/A
< LLD
< LLD
< LLD N/A 0
Zn-65 N/A
< LLD
< LLD
< LLD N/A 0
Nb-95 N/A
< LLD
< LLD
< LLD N/A 0
Zr-95 N/A
< LLD
< LLD
< LLD N/A 0
I-131 60
< LLD
< LLD
< LLD N/A 0
Cs-134 60
< LLD
< LLD
< LLD N/A 0
Cs-137 80
< LLD
< LLD
< LLD N/A 0
Ba-140 N/A
< LLD
< LLD
< LLD N/A 0
La-140 N/A
< LLD
< LLD
< LLD N/A 0
Vegetation (pCi/Kg-wet)
- Gamma, 51 Mn-54 N/A
< LLD
< LLD
< LLD
< LLD 0
Co-58 N/A
< LLD
< LLD
< LLD
< LLD 0
Fe-59 N/A
< LLD
< LLD
< LLD
< LLD 0
Co-60 N/A
< LLD
< LLD
< LLD
< LLD 0
Zn-65 N/A
< LLD
< LLD
< LLD
< LLD 0
Nb-95 N/A
< LLD
< LLD
< LLD
< LLD 0
Zr-95 N/A
< LLD
< LLD
< LLD
< LLD 0
I-131 60
< LLD
< LLD
< LLD
< LLD 0
Cs-134 60
< LLD
< LLD
< LLD
< LLD 0
Cs-137 80
< LLD
< LLD
< LLD
< LLD 0
Ba-140 N/A
< LLD
< LLD
< LLD
< LLD 0
La-140 N/A
< LLD
< LLD
< LLD
< LLD 0
5 Mean and range are based on detectable measurements only.
6 Fraction are based on detectable measurements at specified locations is indicated in parentheses.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 35 of 76 Company: Constellation Plant: Dresden Clean Energy Center
, Data Table Summary Table 10: Dresden Station Data Summary Table Medium or Pathway Sampled (Units)
Type, Total Number of Analyses performed (e.g., I-131, 400)
Lower Limit of Detection (LLD)
Indicator Mean5; (f6).
Range5 Location with Highest Annual Mean Control Mean5 (f6).
Range5 Number of Nonroutine Reported Measurements Name Distance and Direction Mean5 (f6)
Range5 Surface Water (pCi/lL)
Gross Beta, 36 4
D-21 0
9.9 (11/12)
IL River at EJ&E Bridge 9.9 (11/12) 8.3 (22/24)
(6.3/14.2) 1.4 miles WNW (6.3/14.2)
(3.1/14.4)
H-3, 12 200 D-57 0
335.3 (3/4)
Kankakee River at Will Road 1233 (4/4) 1233 (4/4)
(230/398) 2.0 miles SE (322/1780)
(322/1780)
- Gamma, 36 Mn-54 15
< LLD
< LLD
< LLD
< LLD 0
Co-58 15
< LLD
< LLD
< LLD
< LLD 0
Fe-59 30
< LLD
< LLD
< LLD
< LLD 0
Co-60 15
< LLD
< LLD
< LLD
< LLD 0
Zn-65 30
< LLD
< LLD
< LLD
< LLD 0
Nb-95 15
< LLD
< LLD
< LLD
< LLD 0
Zr-95 30
< LLD
< LLD
< LLD
< LLD 0
I-131 15
< LLD
< LLD
< LLD
< LLD 0
Cs-134 15
< LLD
< LLD
< LLD
< LLD 0
Cs-137 18
< LLD
< LLD
< LLD
< LLD 0
Ba-140 60
< LLD
< LLD
< LLD
< LLD 0
La-140 15
< LLD
< LLD
< LLD
< LLD 0
5 Mean and range are based on detectable measurements only.
6 Fraction are based on detectable measurements at specified locations is indicated in parentheses.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 36 of 76 Company: Constellation Plant: Dresden Clean Energy Center
, Data Table Summary Table 10: Dresden Station Data Summary Table Medium or Pathway Sampled (Units)
Type, Total Number of Analyses performed (e.g., I-131, 400)
Lower Limit of Detection (LLD)
Indicator Mean5; (f6).
Range5 Location with Highest Annual Mean Control Mean5 (f6).
Range5 Number of Nonroutine Reported Measurements Name Distance and Direction Mean5 (f6)
Range5 Ground Water (pCi/lL)
H-3, 12 200
<LLD
<LLD
<LLD N/A 0
- Gamma, 12 Mn-54 15
< LLD
< LLD
< LLD N/A 0
Co-58 15
< LLD
< LLD
< LLD N/A 0
Fe-59 30
< LLD
< LLD
< LLD N/A 0
Co-60 15
< LLD
< LLD
< LLD N/A 0
Zn-65 30
< LLD
< LLD
< LLD N/A 0
Nb-95 15
< LLD
< LLD
< LLD N/A 0
Zr-95 30
< LLD
< LLD
< LLD N/A 0
I-131 15
< LLD
< LLD
< LLD N/A 0
Cs-134 15
< LLD
< LLD
< LLD N/A 0
Cs-137 18
< LLD
< LLD
< LLD N/A 0
Ba-140 60
< LLD
< LLD
< LLD N/A 0
La-140 15
< LLD
< LLD
< LLD N/A 0
5 Mean and range are based on detectable measurements only.
6 Fraction are based on detectable measurements at specified locations is indicated in parentheses.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 37 of 76 Company: Constellation Plant: Dresden Clean Energy Center
, Data Table Summary Table 10: Dresden Station Data Summary Table Medium or Pathway Sampled (Units)
Type, Total Number of Analyses performed (e.g., I-131, 400)
Lower Limit of Detection (LLD)
Indicator Mean5; (f6).
Range5 Location with Highest Annual Mean Control Mean5 (f6).
Range5 Number of Nonroutine Reported Measurements Name Distance and Direction Mean5 (f6)
Range5 Fish (pCi/kg Wet)
Gamma, 8 Mn-54 130
< LLD
< LLD
< LLD
< LLD 0
Co-58 130
< LLD
< LLD
< LLD
< LLD 0
Fe-59 260
< LLD
< LLD
< LLD
< LLD 0
Co-60 130
< LLD
< LLD
< LLD
< LLD 0
Zn-65 260
< LLD
< LLD
< LLD
< LLD 0
Nb-95 N/A
< LLD
< LLD
< LLD
< LLD 0
Zr-95 N/A
< LLD
< LLD
< LLD
< LLD 0
Cs-134 130
< LLD
< LLD
< LLD
< LLD 0
Cs-137 150
< LLD
< LLD
< LLD
< LLD 0
Ba-140 N/A
< LLD
< LLD
< LLD
< LLD 0
La-140 N/A
< LLD
< LLD
< LLD
< LLD 0
Sediment (pCi/kg Dry)
Gamma, 2 Mn-54 N/A
< LLD
< LLD
< LLD
< LLD 0
Co-58 N/A
< LLD
< LLD
< LLD
< LLD 0
Fe-59 N/A
< LLD
< LLD
< LLD
< LLD 0
Co-60 N/A
< LLD
< LLD
< LLD
< LLD 0
Zn-65 N/A
< LLD
< LLD
< LLD
< LLD 0
Nb-95 N/A
< LLD
< LLD
< LLD
< LLD 0
Zr-95 N/A
< LLD
< LLD
< LLD
< LLD 0
Cs-134 150
< LLD
< LLD
< LLD
< LLD 0
Cs-137 180
< LLD
< LLD
< LLD
< LLD 0
Ba-140 N/A
< LLD
< LLD
< LLD
< LLD 0
La-140 N/A
< LLD
< LLD
< LLD
< LLD 0
5 Mean and range are based on detectable measurements only.
6 Fraction are based on detectable measurements at specified locations is indicated in parentheses.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 38 of 76 Company: Constellation Plant: Dresden Clean Energy Center
, Complete Data Table for All Analysis Results Obtained In 2024 Note: Throughout Attachment 2, bold data entries are for the reported concentration Table 11, Weekly Air Particulate Gross Beta (E-3 pCi/m3)
Collection Date D-01 D-02 D-03 D-04 D-07 D-45 D-53 D-56 D-58 01/05/2024 18
+/-
4 20
+/-
4 (1) 16
+/-
4 20
+/-
4 18
+/-
4 19
+/-
4 21
+/-
4 18
+/-
4 01/12/2024 19
+/-
4 24
+/-
5 (1) 11
+/-
4 23
+/-
4 23
+/-
5 19
+/-
4 19
+/-
4 23
+/-
5 01/19/2024 (1) 20
+/-
4 (1)
(1) 20
+/-
4 25
+/-
5 21
+/-
5 21
+/-
5 27
+/-
5 01/26/2024 10
+/-
4 13
+/-
4 (1)
(1) 10
+/-
4 9
+/-
4 9
+/-
4 12
+/-
4 11
+/-
4 02/02/2024 13
+/-
4 14
+/-
4 16
+/-
9 14
+/-
4 16
+/-
4 19
+/-
4 15
+/-
4 12
+/-
4 19
+/-
4 02/09/2024 13
+/-
4 14
+/-
4 14
+/-
4 15
+/-
4 14
+/-
4 16
+/-
4 14
+/-
4 13
+/-
4 17
+/-
4 02/16/2024 14
+/-
4 15
+/-
4 20
+/-
4 15
+/-
4 20
+/-
4 19
+/-
4 17
+/-
4 16
+/-
4 19
+/-
4 02/23/2024 13
+/-
8 19
+/-
4 18
+/-
4 21
+/-
5 17
+/-
4 18
+/-
4 14
+/-
4 14
+/-
4 15
+/-
4 03/01/2024 18
+/-
4 17
+/-
4 17
+/-
4 14
+/-
4 14
+/-
4 13
+/-
4 16
+/-
4 15
+/-
4 18
+/-
4 03/08/2024 16
+/-
4 12
+/-
4 12
+/-
4 17
+/-
4 14
+/-
4 15
+/-
4 15
+/-
4 15
+/-
4 17
+/-
4 03/15/2024 14
+/-
4 18
+/-
4 21
+/-
5 13
+/-
4 14
+/-
4 18
+/-
4 15
+/-
4 14
+/-
4 14
+/-
4 03/22/2024 14
+/-
4 11
+/-
4 14
+/-
4 12
+/-
4 14
+/-
4 12
+/-
4 11
+/-
4 10
+/-
4 12
+/-
4 03/29/2024 13
+/-
3 16
+/-
4 15
+/-
4 16
+/-
4 16
+/-
4 13
+/-
4 14
+/-
4 14
+/-
4 17
+/-
4 04/05/2024 7
+/-
3 5
12
+/-
4 9
+/-
4 8
+/-
4 8
+/-
4 7
+/-
4 5
+/-
3 8
+/-
4 04/12/2024 9
+/-
3 9
+/-
3 12
+/-
4 13
+/-
4 10
+/-
3 11
+/-
4 12
+/-
4 12
+/-
4 9
+/-
3 04/19/2024 11
+/-
4 11
+/-
4 11
+/-
4 12
+/-
4 11
+/-
4 16
+/-
4 17
+/-
4 13
+/-
4 14
+/-
4 04/26/2024 16
+/-
4 14
+/-
4 16
+/-
4 17
+/-
4 13
+/-
4 14
+/-
4 18
+/-
4 17
+/-
4 17
+/-
4 05/03/2024 15
+/-
4 13
+/-
4 16
+/-
4 16
+/-
4 12
+/-
4 13
+/-
4 19
+/-
4 17
+/-
4 18
+/-
4 05/10/2024 12
+/-
4 11
+/-
4 12
+/-
4 12
+/-
4 11
+/-
4 8
+/-
4 12
+/-
6 13
+/-
4 10
+/-
4 05/17/2024 13
+/-
4 12
+/-
4 12
+/-
4 13
+/-
4 11
+/-
3 13
+/-
4 17
+/-
6 13
+/-
4 13
+/-
4 05/24/2024 13
+/-
4 16
+/-
4 15
+/-
4 16
+/-
4 14
+/-
4 18
+/-
4 18
+/-
4 14
+/-
4 11
+/-
4 (1) See Sample Deviations Table (Table 9)
Annual Radiological Environmental Operating Report YEAR: 2024 Page 39 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 11, Weekly Air Particulate Gross Beta (E-3 pCi/m3) Contd (1) See Sample Deviations Table (Table 9)
Collection Date D-08 D-10 D-14 D-55 D-12 01/05/2024 19
+/-
4 18
+/-
4 20
+/-
4 16
+/-
4 18
+/-
4 01/12/2024 18
+/-
4 20
+/-
4 21
+/-
4 20
+/-
4 (1) 01/19/2024 26
+/-
5 17
+/-
4 27
+/-
5 23
+/-
5 21
+/-
5 01/26/2024 11
+/-
4 14
+/-
4 11
+/-
4 10
+/-
4 13
+/-
4 02/02/2024 18
+/-
4 13
+/-
4 15
+/-
4 17
+/-
4 16
+/-
4 02/09/2024 15
+/-
4 16
+/-
4 17
+/-
4 15
+/-
4 14
+/-
4 02/16/2024 16
+/-
4 18
+/-
4 15
+/-
4 17
+/-
4 13
+/-
4 02/23/2024 17
+/-
4 16
+/-
4 16
+/-
4 14
+/-
4 20
+/-
4 03/01/2024 13
+/-
4 14
+/-
4 18
+/-
4 14
+/-
4 20
+/-
4 03/08/2024 15
+/-
4 15
+/-
4 18
+/-
4 14
+/-
4 16
+/-
4 03/15/2024 16
+/-
4 14
+/-
4 18
+/-
4 17
+/-
4 15
+/-
4 03/22/2024 10
+/-
4 15
+/-
4 13
+/-
4 16
+/-
4 14
+/-
4 03/29/2024 14
+/-
4 13
+/-
3 18
+/-
4 14
+/-
4 13
+/-
3 04/05/2024 8
+/-
4 6
+/-
3 7
+/-
3 8
+/-
4 7
+/-
4 04/12/2024 11
+/-
4 12
+/-
4 10
+/-
4 12
+/-
4 9
+/-
3 04/19/2024 13
+/-
4 14
+/-
4 16
+/-
4 11
+/-
4 13
+/-
4 04/26/2024 18
+/-
4 14
+/-
4 13
+/-
4 18
+/-
4 19
+/-
4 05/03/2024 12
+/-
4 14
+/-
4 13
+/-
4 17
+/-
4 15
+/-
4 05/10/2024 7
+/-
4 10
+/-
4 12
+/-
4 11
+/-
4 8
+/-
4 05/17/2024 10
+/-
4 12
+/-
4 14
+/-
4 16
+/-
4 13
+/-
4 05/24/2024 15
+/-
4 14
+/-
4 15
+/-
4 19
+/-
4 15
+/-
4
Annual Radiological Environmental Operating Report YEAR: 2024 Page 40 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 11, Weekly Air Particulate Gross Beta (E-3 pCi/m3) Contd Collection Date D-01 D-02 D-03 D-04 D-07 D-45 D-53 D-56 D-58 05/31/2024 10
+/-
4 11
+/-
4 9
+/-
4 10
+/-
4 10
+/-
4 11
+/-
4 13
+/-
4 13
+/-
4 13
+/-
4 06/07/2024 18
+/-
4 15
+/-
4 13
+/-
4 11
+/-
4 14
+/-
4 14
+/-
4 19
+/-
4 14
+/-
4 14
+/-
4 06/14/2024 12
+/-
4 10
+/-
4 8
+/-
4 8
+/-
4 7
+/-
4 10
+/-
4 13
+/-
4 10
+/-
4 14
+/-
4 06/21/2024 16
+/-
4 18
+/-
4 18
+/-
4 14
+/-
4 21
+/-
5 17
+/-
4 16
+/-
4 19
+/-
4 15
+/-
4 06/28/2024 15
+/-
4 13
+/-
4 11
+/-
4 12
+/-
4 10
+/-
3 16
+/-
4 13
+/-
4 12
+/-
4 14
+/-
4 07/05/2024 10
+/-
4 10
+/-
4 11
+/-
4 9
+/-
4 9
+/-
4 17
+/-
4 14
+/-
4 11
+/-
4 14
+/-
4 07/12/2024 15
+/-
4 17
+/-
4 16
+/-
4 16
+/-
4 14
+/-
4 19
+/-
4 16
+/-
4 13
+/-
4 14
+/-
4 07/19/2024 23
+/-
8 15
+/-
4 17
+/-
4 12
+/-
4 13
+/-
4 15
+/-
4 17
+/-
4 20
+/-
4 18
+/-
4 07/26/2024 11
+/-
7 15
+/-
5 14
+/-
5 16
+/-
5 11
+/-
4 14
+/-
5 12
+/-
4 17
+/-
5 16
+/-
5 08/02/2024 15
+/-
4 15
+/-
4 10
+/-
4 15
+/-
4 16
+/-
4 19
+/-
4 16
+/-
4 20
+/-
4 17
+/-
4 08/09/2024 18
+/-
4 18
+/-
4 20
+/-
4 23
+/-
4 14
+/-
4 17
+/-
4 22
+/-
4 25
+/-
5 21
+/-
4 08/16/2024 19
+/-
4 21
+/-
5 20
+/-
4 19
+/-
4 15
+/-
4 20
+/-
4 24
+/-
5 26
+/-
5 21
+/-
5 08/23/2024 12
+/-
4 16
+/-
4 12
+/-
4 12
+/-
4 11
+/-
4 14
+/-
4 13
+/-
4 14
+/-
4 15
+/-
4 08/30/2024 28
+/-
5 25
+/-
5 27
+/-
5 33
+/-
5 22
+/-
5 24
+/-
5 26
+/-
5 29
+/-
5 30
+/-
5 09/06/2024 22
+/-
4 19
+/-
4 20
+/-
4 24
+/-
5 18
+/-
4 19
+/-
4 19
+/-
4 19
+/-
4 21
+/-
4 09/14/2024 18
+/-
4 21
+/-
4 21
+/-
4 21
+/-
4 17
+/-
4 25
+/-
4 21
+/-
4 23
+/-
4 25
+/-
4 09/20/2024 30
+/-
5 29
+/-
5 34
+/-
6 36
+/-
6 30
+/-
5 32
+/-
5 29
+/-
5 35
+/-
6 32
+/-
5 09/27/2024 18
+/-
4 18
+/-
4 22
+/-
4 24
+/-
5 21
+/-
4 22
+/-
4 29
+/-
5 25
+/-
5 20
+/-
4 10/04/2024 21
+/-
4 17
+/-
4 23
+/-
5 23
+/-
5 26
+/-
5 24
+/-
5 21
+/-
5 19
+/-
4 21
+/-
4 10/11/2024 20
+/-
5 23
+/-
5 22
+/-
5 25
+/-
5 22
+/-
5 22
+/-
5 30
+/-
5 27
+/-
5 20
+/-
5 10/18/2024 18
+/-
4 17
+/-
4 20
+/-
4 24
+/-
4 20
+/-
4 25
+/-
5 27
+/-
5 25
+/-
5 23
+/-
4 10/25/2024 24
+/-
5 23
+/-
5 27
+/-
5 30
+/-
5 28
+/-
5 25
+/-
5 34
+/-
5 30
+/-
5 24
+/-
5
Annual Radiological Environmental Operating Report YEAR: 2024 Page 41 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 11, Weekly Air Particulate Gross Beta (E-3 pCi/m3) Contd Collection Date D-08 D-10 D-14 D-55 D-12 05/31/2024 13
+/-
4 10
+/-
4 10
+/-
4 13
+/-
4 10
+/-
4 06/07/2024 13
+/-
4 13
+/-
4 15
+/-
4 13
+/-
4 13
+/-
4 06/14/2024 8
+/-
4 11
+/-
4 11
+/-
4 10
+/-
4 11
+/-
4 06/21/2024 19
+/-
4 15
+/-
4 15
+/-
4 19
+/-
4 18
+/-
4 06/28/2024 14
+/-
4 12
+/-
4 14
+/-
4 14
+/-
4 14
+/-
4 07/05/2024 10
+/-
4 15
+/-
4 13
+/-
4 17
+/-
4 12
+/-
4 07/12/2024 17
+/-
4 16
+/-
4 19
+/-
4 18
+/-
4 18
+/-
4 07/19/2024 15
+/-
4 14
+/-
4 21
+/-
4 15
+/-
5 16
+/-
4 07/26/2024 16
+/-
5 18
+/-
5 18
+/-
5 15
+/-
5 14
+/-
5 08/02/2024 13
+/-
4 12
+/-
4 22
+/-
4 21
+/-
4 14
+/-
4 08/09/2024 21
+/-
4 20
+/-
4 25
+/-
5 25
+/-
5 20
+/-
4 08/16/2024 20
+/-
4 21
+/-
5 27
+/-
5 23
+/-
5 19
+/-
4 08/23/2024 15
+/-
4 15
+/-
4 14
+/-
4 17
+/-
4 14
+/-
4 08/30/2024 27
+/-
5 26
+/-
5 29
+/-
5 33
+/-
5 26
+/-
5 09/06/2024 20
+/-
4 17
+/-
4 23
+/-
4 21
+/-
4 18
+/-
4 09/14/2024 25
+/-
4 21
+/-
4 22
+/-
4 24
+/-
4 24
+/-
4 09/20/2024 33
+/-
5 31
+/-
5 36
+/-
6 37
+/-
6 27
+/-
5 09/27/2024 22
+/-
5 17
+/-
4 26
+/-
5 20
+/-
4 22
+/-
4 10/04/2024 18
+/-
4 19
+/-
4 19
+/-
4 22
+/-
5 20
+/-
4 10/11/2024 23
+/-
5 21
+/-
5 27
+/-
5 26
+/-
5 22
+/-
5 10/18/2024 18
+/-
4 24
+/-
4 23
+/-
4 28
+/-
5 25
+/-
5 10/25/2024 26
+/-
5 25
+/-
5 25
+/-
5 25
+/-
5 26
+/-
5
Annual Radiological Environmental Operating Report YEAR: 2024 Page 42 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 11, Weekly Air Particulate Gross Beta (E-3 pCi/m3) Contd Collection Date D-01 D-02 D-03 D-04 D-07 D-45 D-53 D-56 D-58 11/01/2024 59
+/-
11 25
+/-
5 26
+/-
5 24
+/-
5 27
+/-
5 26
+/-
5 37
+/-
5 29
+/-
5 24
+/-
4 11/08/2024 11
+/-
4 13
+/-
4 12
+/-
4 13
+/-
4 15
+/-
4 9
+/-
4 12
+/-
4 14
+/-
4 12
+/-
4 11/15/2024 20
+/-
4 43
+/-
13 18
+/-
4 17
+/-
4 24
+/-
4 22
+/-
4 (1) 21
+/-
4 21
+/-
4 11/22/2024 20
+/-
4 (1) 23
+/-
5 24
+/-
5 20
+/-
4 25
+/-
5 26
+/-
5 39
+/-
5 21
+/-
4 11/29/2024 13
+/-
4 (1) 16
+/-
4 20
+/-
4 18
+/-
4 16
+/-
4 15
+/-
4 15
+/-
4 19
+/-
4 12/06/2024 20
+/-
4 (1) 22
+/-
5 23
+/-
5 23
+/-
5 23
+/-
5 20
+/-
4 22
+/-
5 22
+/-
4 12/13/2024 21
+/-
4 (1) 22
+/-
4 28
+/-
5 24
+/-
4 23
+/-
4 23
+/-
4 24
+/-
4 19
+/-
4 12/20/2024 22
+/-
5 (1) 25
+/-
5 32
+/-
5 27
+/-
5 32
+/-
5 35
+/-
5 28
+/-
5 25
+/-
5 12/27/2024 17
+/-
4 (1) 15
+/-
4 37
+/-
5 21
+/-
5 22
+/-
5 18
+/-
4 17
+/-
4 19
+/-
5 01/03/2025 28
+/-
4 (1) 29
+/-
5 24
+/-
4 27
+/-
4 31
+/-
5 30
+/-
5 27
+/-
4 25
+/-
4 (1) See Sample Deviations Table (Table 9)
Annual Radiological Environmental Operating Report YEAR: 2024 Page 43 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 11, Weekly Air Particulate Gross Beta (E-3 pCi/m3) Contd Collection Date D-08 D-10 D-14 D-55 D-12 11/01/2024 29
+/-
5 34
+/-
5 32
+/-
5 29
+/-
5 26
+/-
5 11/08/2024 14
+/-
4 14
+/-
4 12
+/-
4 15
+/-
4 13
+/-
4 11/15/2024 21
+/-
4 22
+/-
4 21
+/-
4 22
+/-
4 24
+/-
4 11/22/2024 30
+/-
5 26
+/-
5 25
+/-
5 20
+/-
4 26
+/-
5 11/29/2024 19
+/-
4 18
+/-
4 19
+/-
4 18
+/-
4 18
+/-
4 12/06/2024 22
+/-
5 25
+/-
5 28
+/-
5 21
+/-
5 21
+/-
5 12/13/2024 24
+/-
4 26
+/-
5 24
+/-
4 19
+/-
4 19
+/-
5 12/20/2024 21
+/-
5 25
+/-
5 27
+/-
5 33
+/-
5 33
+/-
5 12/27/2024 20
+/-
4 19
+/-
4 21
+/-
5 19
+/-
4 19
+/-
4 01/03/2025 25
+/-
4 23
+/-
4 30
+/-
5 26
+/-
4 27
+/-
4
Annual Radiological Environmental Operating Report YEAR: 2024 Page 44 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 12, Quarterly Air Particulate Gamma Isotopic (pCi/m3 +/- 2 Sigma)
Station Nuclide Q1 Q2 Q3 Q4 Station Nuclide Q1 Q2 Q3 Q4 D-01 Mn-54 3
3
< 2 3
D-03 Mn-54 3
< 2 2
2 Co-58 2
3
< 3 3
Co-58 3
< 4 2
2 Fe-59 5
8
< 7 6
Fe-59 9
< 9 4
4 Co-60 2
3
< 3 4
Co-60 3
< 4 2
3 Zn-65 6
5 7
8 Zn-65 7
< 7 5
5 Nb-95 3
3
< 3 3
Nb-95 3
< 3 2
2 Zr-95 4
5
< 5 5
Zr-95 5
< 6 3
3 Cs-134 2
3
< 3 3
Cs-134 3
< 2 2
2 Cs-137 2
2
< 3 3
Cs-137 3
< 3 1
2 Ba-140 12 42
< 19 23 Ba-140 18
< 43 10 13 La-140 5
20
< 5 9
La-140 6
< 13 5
7 D-02 Mn-54 2
2
< 2 4
D-04 Mn-54 2
< 2 3
2 Co-58 1
2
< 2 7
Co-58 3
< 3 3
3 Fe-59 6
6
< 5 20 Fe-59 6
< 7 7
7 Co-60 3
2
< 1 5
Co-60 3
< 2 3
3 Zn-65 5
2
< 6 11 Zn-65 7
< 5 10 7
Nb-95 2
2
< 2 9
Nb-95 2
< 2 3
3 Zr-95 3
4
< 4 12 Zr-95 4
< 5 6
4 Cs-134 2
2
< 2 4
Cs-134 3
< 2 4
2 Cs-137 2
2
< 2 4
Cs-137 2
< 2 4
2 Ba-140 16 27
< 9 416A Ba-140 15
< 35 19 21 La-140 3
16
< 3 222A La-140 8
< 13 7
8 A Anomalous results identified. Dresden will track the sample and trend the sample location results to ensure there not a trend developing.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 45 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 12, Quarterly Air Particulate Gamma Isotopic (pCi/m3 +/- 2 Sigma) Contd Station Nuclide Q1 Q2 Q3 Q4 Station Nuclide Q1 Q2 Q3 Q4 D-07 Mn-54 3
3 1
2 D-08 Mn-54 2
3 2
3 Co-58 3
3 1
2 Co-58 2
3 2
3 Fe-59 7
8 4
5 Fe-59 2
11 5
5 Co-60 3
2 1
3 Co-60 3
3 2
3 Zn-65 7
5 4
7 Zn-65 6
7 5
6 Nb-95 3
3 1
3 Nb-95 2
5 1
3 Zr-95 5
4 1
5 Zr-95 3
7 2
6 Cs-134 3
2 2
3 Cs-134 2
3 2
3 Cs-137 3
2 1
3 Cs-137 2
3 2
3 Ba-140 14 31 8
22 Ba-140 7
46 12 19 La-140 9
11 4
9 La-140 5
25 4
10 D-10 Mn-54 2
2 2
2 D-12 Mn-54 3
3 2
2 Co-58 2
3 2
2 Co-58 3
4 2
2 Fe-59 5
2 5
4 Fe-59 7
12 5
5 Co-60 2
3 3
2 Co-60 3
3 3
2 Zn-65 6
6 5
4 Zn-65 8
9 7
5 Nb-95 3
3 2
2 Nb-95 3
4 2
2 Zr-95 5
5 4
4 Zr-95 5
8 4
3 Cs-134 3
3 3
2 Cs-134 3
4 2
1 Cs-137 3
2 1
2 Cs-137 3
3 2
2 Ba-140 15 27 12 17 Ba-140 17 70 13 14 La-140 4
12 6
5 La-140 7
24 5
9
Annual Radiological Environmental Operating Report YEAR: 2024 Page 46 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 12, Quarterly Air Particulate Gamma Isotopic (pCi/m3 +/- 2 Sigma) Contd Station Nuclide Q1 Q2 Q3 Q4 Station Nuclide Q1 Q2 Q3 Q4 D-14 Mn-54 2
1 3
2 D-53 Mn-54 2
3 2
2 Co-58 2
3 3
2 Co-58 2
4 1
2 Fe-59 6
6 6
5 Fe-59 5
10 5
6 Co-60 3
2 3
3 Co-60 3
3 2
3 Zn-65 8
4 9
6 Zn-65 5
6 5
6 Nb-95 2
2 4
2 Nb-95 2
3 2
3 Zr-95 3
4 5
4 Zr-95 5
6 3
5 Cs-134 3
2 2
2 Cs-134 2
2 2
3 Cs-137 2
2 3
2 Cs-137 2
2 2
2 Ba-140 13 35 18 21 Ba-140 13 39 11 21 La-140 6
14 7
10 La-140 2
17 5
7 D-45 Mn-54 2
3 2
2 D-55 Mn-54 3
4 2
3 Co-58 2
2 3
2 Co-58 3
4 2
3 Fe-59 5
6 5
6 Fe-59 7
9 5
6 Co-60 2
3 3
3 Co-60 4
5 2
1 Zn-65 6
6 7
4 Zn-65 6
8 6
4 Nb-95 2
3 3
2 Nb-95 4
4 2
2 Zr-95 5
6 4
5 Zr-95 6
10 5
5 Cs-134 3
3 2
3 Cs-134 4
3 3
3 Cs-137 2
2 2
2 Cs-137 3
4 2
2 Ba-140 11 49 16 17 Ba-140 17 60 17 21 La-140 5
12 7
10 La-140 7
34 7
11
Annual Radiological Environmental Operating Report YEAR: 2024 Page 47 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 12, Quarterly Air Particulate Gamma Isotopic (pCi/m3 +/- 2 Sigma) Contd Station Nuclide Q1 Q2 Q3 Q4 D-56 Mn-54 2
2 2
2 Co-58 2
4 2
2 Fe-59 5
8 5
5 Co-60 2
2 3
2 Zn-65 5
6 5
4 Nb-95 2
3 2
2 Zr-95 4
4 5
4 Cs-134 2
3 2
2 Cs-137 2
3 1
2 Ba-140 11 46 10 17 La-140 3
12 6
7 D-58 Mn-54 2
3 2
2 Co-58 2
2 2
2 Fe-59 4
8 3
5 Co-60 1
3 3
2 Zn-65 6
5 5
4 Nb-95 2
3 2
2 Zr-95 5
4 3
3 Cs-134 2
3 2
2 Cs-137 2
2 2
2 Ba-140 10 37 10 15 La-140 7
13 6
6
Annual Radiological Environmental Operating Report YEAR: 2024 Page 48 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 13, Weekly Air Iodine I-131 (E-3 pCi/m3)
Collection Date D-01 D-02 D-03 D-04 D-07 D-45 D-53 D-56 D-58 01/05/2024 47 47 (1) 47 20 37 36 37 37 01/12/2024 44 43 (1) 44 28 51 50 40 40 01/19/2024 (1) 24 (1)
(1) 58 23 53 53 21 01/26/2024 41 42 (1)
(1) 43 41 40 19 40 02/02/2024 60 60 61 60 57 54 56 56 56 02/09/2024 57 57 57 57 25 36 29 29 29 02/16/2024 27 12 27 27 26 40 37 37 37 02/23/2024 52 52 52 52 23 35 15 35 34 03/01/2024 31 31 31 31 22 29 21 28 28 03/08/2024 24 24 24 16 23 30 36 36 36 03/15/2024 34 34 34 34 29 37 36 15 36 03/22/2024 35 32 32 32 31 40 32 32 32 03/29/2024 17 16 16 17 19 22 11 11 11 04/05/2024 37 18 38 37 37 35 38 38 38 04/12/2024 27 21 27 27 27 44 36 36 36 04/19/2024 33 36 33 33 33 16 42 42 42 04/26/2024 37 38 38 38 30 28 27 12 27 05/03/2024 29 30 30 22 30 22 34 34 34 05/10/2024 31 31 31 31 39 33 43 33 33 05/17/2024 35 35 15 35 33 16 28 21 21 05/24/2024 28 28 27 28 21 16 53 53 53 (1) See Sample Deviations Table (Table 9)
Annual Radiological Environmental Operating Report YEAR: 2024 Page 49 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 13, Weekly Air Iodine I-131 (E-3 pCi/m3) Contd (1) See sample deviation table (Table 9)
Collection Date D-08 D-10 D-14 D-55 D-12 01/05/2024 46 28 37 38 37 01/12/2024 43 51 51 41 (1) 01/19/2024 58 58 54 53 58 01/26/2024 43 43 43 41 18 02/02/2024 53 53 23 57 54 02/09/2024 36 36 15 29 36 02/16/2024 19 39 40 38 40 02/23/2024 31 31 31 35 31 03/01/2024 32 32 33 29 33 03/08/2024 30 15 30 36 30 03/15/2024 29 29 33 37 29 03/22/2024 17 40 40 32 40 03/29/2024 22 9
22 11 22 04/05/2024 35 27 35 39 35 04/12/2024 43 18 44 37 44 04/19/2024 31 31 31 43 31 04/26/2024 33 30 30 28 30 05/03/2024 22 22 15 35 22 05/10/2024 40 17 40 33 40 05/17/2024 38 38 38 21 38 05/24/2024 38 38 38 54 38
Annual Radiological Environmental Operating Report YEAR: 2024 Page 50 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 13, Weekly Air Iodine I-131 (E-3 pCi/m3) Contd Collection Date D-01 D-02 D-03 D-04 D-07 D-45 D-53 D-56 D-58 05/31/2024 27 13 27 27 27 31 25 24 24 06/07/2024 37 38 38 38 16 47 34 34 34 06/14/2024 31 16 31 31 31 35 34 34 34 06/21/2024 36 36 36 36 16 38 29 29 29 06/28/2024 31 31 31 14 31 45 23 23 23 07/05/2024 49 21 50 49 50 34 43 43 43 07/12/2024 39 39 39 39 34 21 16 21 21 07/19/2024 50 32 32 32 34 38 36 36 36 07/26/2024 40 33 33 33 32 39 37 36 36 08/02/2024 28 28 28 28 13 28 14 27 27 08/09/2024 14 32 32 32 32 43 38 38 38 08/16/2024 35 36 36 35 19 42 34 34 34 08/23/2024 15 15 15 10 14 33 34 33 33 08/30/2024 37 16 37 37 37 39 35 35 35 09/06/2024 24 34 34 34 32 29 25 25 25 09/14/2024 19 19 19 13 20 31 33 33 32 09/20/2024 48 49 48 48 22 49 47 47 47 09/27/2024 20 45 45 45 43 36 40 40 40 10/04/2024 13 26 26 26 26 25 33 33 33 10/11/2024 37 37 37 37 27 38 18 37 38 10/18/2024 19 38 38 38 39 35 41 40 39 10/25/2024 35 35 35 35 19 34 34 34 22
Annual Radiological Environmental Operating Report YEAR: 2024 Page 51 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 13, Weekly Air Iodine I-131 (E-3 pCi/m3) Contd Collection Date D-08 D-10 D-14 D-55 D-12 05/31/2024
< 31 31 21 25 31 06/07/2024
< 46 46 22 35 46 06/14/2024
< 34 26 35 34 35 06/21/2024
< 34 34 35 30 34 06/28/2024
< 43 43 19 23 43 07/05/2024
< 14 33 34 44 34 07/12/2024
< 35 35 27 21 35 07/19/2024
< 38 38 25 42 38 07/26/2024
< 38 38 19 37 39 08/02/2024
< 25 25 25 28 25 08/09/2024
< 43 22 43 39 43 08/16/2024
< 41 41 22 35 42 08/23/2024
< 33 33 33 34 24 08/30/2024 28 39 39 35 39 09/06/2024 29 29 22 25 29 09/14/2024 31 13 31 33 31 09/20/2024 48 48 36 48 49 09/27/2024 24 36 36 40 36 10/04/2024 24 24 17 33 25 10/11/2024 34 34 35 38 35 10/18/2024 34 34 39 41 34 10/25/2024 42 42 42 34 42
Annual Radiological Environmental Operating Report YEAR: 2024 Page 52 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 13, Weekly Air Iodine I-131 (E-3 pCi/m3) Contd (1) See Sample Deviations Table (Table 9)
Collection Date D-01 D-02 D-03 D-04 D-07 D-45 D-53 D-56 D-58 11/01/2024 35 34 34 34 34 27 31 31 29 11/08/2024 29 14 29 29 29 19 35 35 35 11/15/2024 32 59 32 32 32 35 (1) 33 31 11/22/2024 25 (1) 19 25 25 40 39 28 27 11/29/2024 39 (1) 39 39 44 41 40 40 18 12/06/2024 39 (1) 39 39 39 47 46 41 38 12/13/2024 30 (1) 41 41 41 26 26 24 23 12/20/2024 40 (1) 40 40 40 48 47 49 49 12/27/2024 34 (1) 34 34 35 35 35 24 25 01/03/2025 32 (1) 32 32 32 34 34 26 27
Annual Radiological Environmental Operating Report YEAR: 2024 Page 53 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 13, Weekly Air Iodine I-131 (E-3 pCi/m3) Contd Collection Date D-08 D-10 D-14 D-55 D-12 11/01/2024 37 37 38 31 37 11/08/2024 18 18 12 35 18 11/15/2024 35 17 35 33 35 11/22/2024 25 19 40 29 40 11/29/2024 44 44 45 41 32 12/06/2024 19 46 22 42 47 12/13/2024 41 26 26 24 30 12/20/2024 19 22 49 50 48 12/27/2024 26 35 17 24 35 01/03/2025 25 34 16 26 34
Annual Radiological Environmental Operating Report YEAR: 2024 Page 54 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 14, Monthly/Bi-Weekly Milk I-131 (pCi/L +/- 2 Sigma)
Table 15, Monthly/Bi-Weekly Milk Gamma Isotopic (pCi/L +/- 2 Sigma)
Collection Date Control Farm D-60 06/18/2024 0.7 07/09/2024 0.9 08/27/2024 0.9 09/10/2024 0.8 12/03/2024 0.8 Station Collection Dates Mn-54 Co-58 Fe-59 Co-60 Zn-65 Nb-95 Zr-95 Cs-134 Cs-137 Ba-140 La-140 D-60 06/18/2024 10 13 25 13 25 11 19 11 11 43 12 07/09/2024 11 10 24 12 27 10 18 14 11 46 11 08/13/2024 11 13 30 10 27 12 19 12 10 59 10 09/10/2024 9
10 20 8
18 8
17 9
8 31 9
12/03/2024 7
9 23 12 20 10 15 10 9
36 9
Annual Radiological Environmental Operating Report YEAR: 2024 Page 55 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 16, Annual Vegetation Gamma Isotopic (pCi/kg Wet +/- 2 Sigma)
Station Collection Dates Mn-54 Co-58 Fe-59 Co-60 Zn-65 Nb-95 Zr-95 I-131 Cs-134 Cs-137 Ba-140 La-140 D-25 Collard greens 07/10/2024 30
< 25 66 25 51 25 41 35 30 27 107 27 Red beets 07/10/2024 17
< 20 46 22 47 23 34 30 23 19 96 25 Red beets leaves 07/10/2024 25
< 28 71 33 77 35 56 34 25 31 121 45 Swiss chard 07/10/2024 19
< 19 42 27 46 19 35 24 19 19 81 28 Collard greens 08/14/2024 37
< 32 66 32 94 30 48 33 35 34 133 25 Swiss chard 08/14/2024 28
< 20 73 30 55 20 41 22 30 20 87 20 Turnips 08/14/2024 21
< 19 47 22 42 22 29 27 25 27 80 22 Collard greens 09/20/2024 36
< 34 73 35 68 32 58 48 36 40 144 36 Red beet leaves 09/20/2024 19
< 17 41 19 44 20 32 22 23 19 75 25 Swiss chard 09/20/2024 34
< 35 86 32 109 37 66 44 39 43 166 44 Collard 10/18/2024 47
< 40 82 32 81 40 72 48 44 39 165 52 Red beet leaves 10/18/2024 32
< 35 89 42 87 43 56 50 41 37 129 52 Swiss chard 10/18/2024 33
< 30 62 28 69 28 43 35 34 32 108 34 D-39 Cabbage 07/12/2024 33
< 32 67 26 66 26 51 37 33 34 138 23 Kohlrabi 07/12/2024 23
< 25 59 31 72 27 43 37 28 30 105 39
Annual Radiological Environmental Operating Report YEAR: 2024 Page 56 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 16, Annual Vegetation Gamma Isotopic (pCi/kg Wet +/- 2 Sigma) Contd Station Collection Dates Mn-54 Co-58 Fe-59 Co-60 Zn-65 Nb-95 Zr-95 I-131 Cs-134 Cs-137 Ba-140 La-140 D-42 Kale 07/19/2024 21
< 23 55
< 27 61 22
< 47 31 24 25 101
< 21 Swiss chard 07/19/2024 27
< 32 76
< 33 79 34
< 59 43 32 32 124
< 53 Turnip 07/19/2024 24
< 25 45
< 32 61 27
< 48 35 26 25 96
< 23 Cabbage 08/16/2024 20
< 18 45
< 32 53 25
< 34 26 22 24 89
< 18 Kale 08/16/2024 26
< 25 50
< 26 68 29
< 53 35 30 28 128
< 34 Turnip 08/16/2024 20
< 20 44
< 23 49 22
< 37 26 24 22 87
< 28 Collard 09/20/2024 36
< 23 77
< 40 84 30
< 62 40 27 32 143
< 24 Kale 09/20/2024 31
< 29 52
< 23 69 32
< 51 39 30 29 112
< 39 Rutabaga 09/20/2024 28
< 34 64
< 26 64 27
< 48 33 30 31 111
< 37 Collard 10/18/2024 31
< 29 61
< 30 58 24
< 43 35 31 29 124
< 44 Kale 10/18/2024 34
< 36 58
< 38 77 31
< 66 44 40 35 138
< 35 Turnip 10/18/2024 21
< 19 42
< 17 51 20
< 38 30 23 21 87
< 22
Annual Radiological Environmental Operating Report YEAR: 2024 Page 57 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 16, Annual Vegetation Gamma Isotopic (pCi/kg Wet +/- 2 Sigma) Contd Station Collection Dates Mn-54 Co-58 Fe-59 Co-60 Zn-65 Nb-95 Zr-95 I-131 Cs-134 Cs-137 Ba-140 La-140 D-43 Kale 07/26/2024 35 35 75 42 81 35
< 58 44 40 38
< 122 43 Turnip 07/26/2024 27 34 58 40 74 31
< 62 46 39 35
< 160 42 Collard 07/26/2024 40 39 82 44 92 39
< 68 49 46 41
< 153 53 Kale 08/16/2024 20 20 46 21 50 21
< 37 24 23 22
< 85 18 Turnip 08/16/2024 11 14 26 12 26 11
< 20 15 13 13
< 48 15 Collard 08/16/2024 33 31 62 40 83 37
< 65 46 36 41
< 149 36 Swiss chard 09/20/2024 9
10 19 12 22 10
< 16 13 11 10
< 41 12 Turnip 09/20/2024 19 16 27 19 36 16
< 31 23 21 19
< 70 10 Collard 09/20/2024 31 40 80 36 76 35
< 62 46 40 34
< 182 46 Kale 10/18/2024 38 31 85 40 91 40
< 68 48 38 39
< 162 44 Swiss chard 10/18/2024 29 27 59 36 80 33
< 54 37 33 26
< 107 42 Turnip 10/18/2024 15 13 27 15 34 13
< 23 17 18 14
< 61 15
Annual Radiological Environmental Operating Report YEAR: 2024 Page 58 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 16, Annual Vegetation Gamma Isotopic (pCi/kg Wet +/- 2 Sigma) Contd Station Collection Dates Mn-54 Co-58 Fe-59 Co-60 Zn-65 Nb-95 Zr-95 I-131 Cs-134 Cs-137 Ba-140 La-140 D-44 Kale 07/19/2024 33 33 76 37
< 50
< 38 60 39 39 30
< 142 46 Swiss chard 07/19/2024 30 26 73 34
< 78
< 28 45 39 32 32
< 152 49 Turnip 07/19/2024 33 40 70 41
< 64
< 40 74 48 39 38
< 118 19 Collard 08/16/2024 28 24 49 27
< 61
< 22 42 32 26 28
< 107 29 Kale 08/16/2024 34 30 69 33
< 70
< 31 55 45 34 33
< 115 37 Swiss chard 08/16/2024 26 30 64 40
< 68
< 35 53 42 32 35
< 133 35 Collard 09/20/2024 25 29 57 36
< 65
< 24 42 45 28 28
< 136 30 Swiss chard 09/20/2024 42 26 70 37
< 80
< 31 58 43 33 37
< 136 33 Turnip 09/20/2024 23 22 71 40
< 59
< 26 48 43 29 31
< 120 40 Collard 10/18/2024 37 36 92 36
< 81
< 37 57 47 36 40
< 134 50 Swiss chard 10/18/2024 31 28 72 37
< 83
< 26 55 47 36 35
< 125 36 Turnip 10/18/2024 19 22 50 18
< 67
< 20 28 23 22 20
< 74 25
Annual Radiological Environmental Operating Report YEAR: 2024 Page 59 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 17, Monthly Surface Water Gross Beta (pCi/L +/- 2 Sigma)
Station Collection Dates Gr-B D-52 1/5/2024 1/26/2024 9
+/-
3 2/2/2024 2/23/2024 6
+/-
2 3/1/2024 3/29/2024 13
+/-
4 4/5/2024 4/26/2024 8
+/-
3 5/3/2024 5/31/2024 9
+/-
3 6/7/2024 6/28/2024 10
+/-
3 7/5/2024 7/26/2024 10
+/-
3 8/2/2024 8/30/2024 3
+/-
2 9/6/2024 9/27/2024 14
+/-
4 10/4/2024 10/25/2024 13
+/-
4 11/1/2024 11/29/2024 9
+/-
2 12/20/2024 12/27/2024 14
+/-
3 D-21 12/29/2023 1/26/2024 12
+/-
2 1/26/2024 2/23/2024 6
+/-
2 2/23/2024 3/29/2024 12
+/-
4 3/29/2024 4/26/2024 3
4/26/2024 5/31/2024 6
+/-
2 5/31/2024 6/28/2024 7
+/-
2 6/28/2024 7/26/2024 8
+/-
3 7/26/2024 8/30/2024 14
+/-
3 8/30/2024 9/27/2024 14
+/-
4 9/27/2024 10/25/2024 12
+/-
4 10/25/2024 11/29/2024 6
+/-
2 11/29/2024 12/27/2024 12
+/-
3 D-57 1/26/2024 1/26/2024 14
+/-
3 2/23/2024 2/23/2024 4
+/-
2 3/29/2024 3/29/2024 4
4/26/2024 4/26/2024 4
+/-
2 5/31/2024 5/31/2024 6
+/-
2 6/28/2024 6/28/2024 3
7/26/2024 7/26/2024 7
+/-
3 8/30/2024 8/30/2024 10
+/-
3 9/27/2024 9/27/2024 6
+/-
2 10/25/2024 10/25/2024 5
+/-
3 11/29/2024 11/29/2024 5
+/-
2 12/27/2024 12/27/2024 5
+/-
2
Annual Radiological Environmental Operating Report YEAR: 2024 Page 60 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 18, Monthly Surface Water Gamma Isotopic (pCi/L +/- 2 Sigma)
Station Collection Dates Mn-54 Co-58 Fe-59 Co-60 Zn-65 Nb-95 Zr-95 I-131 Cs-134 Cs-137 Ba-140 La-140 D-21 12/29/2023 01/26/2024 8
10 18 10 12 7
13 12 10 8
< 40
< 11 01/26/2024 02/23/2024 8
6 14 9
15 8
13 10 8
7
< 25
< 14 02/23/2024 03/29/2024 7
8 11 7
20 8
14 11 9
7
< 29
< 9 03/29/2024 04/26/2024 7
7 18 7
13 7
13 9
9 6
< 32
< 10 04/26/2024 05/31/2024 5
7 14 8
10 7
10 9
7 7
< 27
< 14 05/31/2024 06/28/2024 6
7 15 8
14 7
9 11 8
6
< 32
< 15 06/28/2024 07/26/2024 5
4 10 5
11 4
9 7
5 6
< 16
< 6 07/26/2024 08/30/2024 8
8 17 9
16 8
14 11 9
8
< 34
< 9 08/30/2024 09/27/2024 7
7 12 8
17 8
14 12 10 6
< 40
< 12 09/27/2024 10/25/2024 4
4 6
4 8
4 8
7 4
5
< 20
< 7 10/25/2024 11/29/2024 7
7 16 7
14 8
12 12 9
8
< 40
< 7 11/29/2024 12/27/2024 6
6 12 7
13 6
12 11 6
7
< 22
< 8 D-52 01/05/2024 01/26/2024 7
7 13 7
15 7
9 12 8
7
< 31
< 10 02/02/2024 02/23/2024 5
5 12 7
10 6
12 11 6
7
< 32
< 8 03/01/2024 03/29/2024 7
8 9
7 15 7
10 12 8
5
< 33
< 14 04/05/2024 04/26/2024 5
7 15 7
16 8
12 7
7 8
< 31
< 11 05/03/2024 05/31/2024 7
7 16 8
12 6
12 10 7
7
< 30
< 8 06/07/2024 06/28/2024 7
8 17 11 13 7
13 10 5
8
< 27
< 9 07/05/2024 07/26/2024 6
5 14 8
13 6
10 7
6 6
< 24
< 10 08/02/2024 08/30/2024 8
9 16 8
17 8
10 10 7
7
< 32
< 13 09/06/2024 09/27/2024 8
8 20 10 16 9
16 12 7
9
< 30
< 11 10/04/2024 10/25/2024 7
8 14 10 14 7
13 13 7
7
< 34
< 12 11/01/2024 11/29/2024 6
7 13 7
12 7
12 8
7 6
< 30
< 10 12/20/2024 12/27/2024 4
4 9
5 9
4 9
8 4
4
< 19
< 8
Annual Radiological Environmental Operating Report YEAR: 2024 Page 61 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 18, Monthly Surface Water Gamma Isotopic (pCi/L +/- 2 Sigma) Contd Station Collection Dates Mn-54 Co-58 Fe-59 Co-60 Zn-65 Nb-95 Zr-95 I-131 Cs-134 Cs-137 Ba-140 La-140 D-57 01/26/2024 01/26/2024
< 7 8
19 7
17 8
11 12 9
8
< 34
< 11 02/23/2024 02/23/2024
< 7 7
17 6
17 8
11 9
7 6
< 31
< 11 03/29/2024 03/29/2024
< 5 6
14 5
15 5
13 10 8
6
< 25
< 8 04/26/2024 04/26/2024
< 6 7
15 9
16 7
12 11 8
7
< 24
< 7 05/31/2024 05/31/2024
< 8 6
17 7
17 8
15 10 8
7
< 30
< 8 06/28/2024 06/28/2024
< 6 6
13 7
15 6
11 10 8
8
< 33
< 8 07/26/2024 07/26/2024
< 5 5
10 5
13 6
11 8
6 6
< 21
< 9 08/30/2024 08/30/2024
< 7 6
14 6
17 8
12 10 8
6
< 35
< 14 09/27/2024 09/27/2024
< 8 7
16 9
15 7
13 12 9
7
< 37
< 12 10/25/2024 10/25/2024
< 6 6
15 7
17 7
12 9
7 7
< 27
< 9 11/29/2024 11/29/2024
< 8 6
15 6
15 8
12 10 7
7
< 30
< 9 12/27/2024 12/27/2024
< 4 3
9 5
10 4
7 6
4 4
< 17
< 6
Annual Radiological Environmental Operating Report YEAR: 2024 Page 62 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 19, Quarterly Surface Water Tritium (pCi/L +/- 2 Sigma)
Station Collection Dates H-3 D-21 12/29/2023
- 03/29/2024 398
+/-
129 03/29/2024
- 06/28/2024 197 06/28/2024
- 09/27/2024 378
+/- 129 09/27/2024
- 12/27/2024 230
+/-
119 D-52 01/05/2024
- 03/29/2024 183 04/05/2024
- 06/28/2024 197 07/05/2024
- 09/27/2024 180 10/04/2024
- 12/27/2024 177 D-57 12/29/2023
- 03/29/2024 1540
+/-
221 03/29/2024
- 06/28/2024 322
+/-
133 06/28/2024
- 09/27/2024 1780
+/-
249 09/27/2024
- 12/27/2024 1290
+/-
198
Annual Radiological Environmental Operating Report YEAR: 2024 Page 63 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 21, Quarterly Ground Water Gamma Isotopic (pCi/L +/- 2 Sigma)
Table 20, Quarterly Ground Water Tritium (pCi/L +/- 2 Sigma)
Collection Date D-22 D-35 D-39 01/12/2024 195 185
< 186 04/12/2024 194 198
< 199 07/12/2024 185 190
< 188 10/11/2024 190 189
< 189 Station Collection Dates Mn-54 Co-58 Fe-59 Co-60 Zn-65 Nb-95 Zr-95 I-131 Cs-134 Cs-137 Ba-140 La-140 D-22 01/12/2024 01/12/2024 6
6
< 12
< 7
< 15
< 7
< 8
< 11
< 6
< 6 34
< 13 04/12/2024 04/12/2024 5
8
< 17
< 10
< 14
< 6
< 12
< 11
< 6
< 6 25
< 12 07/12/2024 07/12/2024 5
5
< 10
< 4
< 12
< 5
< 9
< 8
< 7
< 6 19
< 8 10/11/2024 10/11/2024 6
7
< 15
< 9
< 15
< 7
< 11
< 11
< 8
< 8 27
< 12 D-35 01/12/2024 01/12/2024 6
6
< 14
< 8
< 15
< 7
< 8
< 14
< 8
< 7 38
< 14 04/12/2024 04/12/2024 6
6
< 15
< 7
< 12
< 6
< 11
< 9
< 6
< 8 32
< 7 07/12/2024 07/12/2024 4
4
< 8
< 5
< 10
< 4
< 7
< 7
< 5
< 5 18
< 5 10/11/2024 10/11/2024 7
8
< 13
< 10
< 17
< 8
< 15
< 11
< 7
< 7 36
< 12 D-39 01/12/2024 01/12/2024 6
6
< 14
< 5
< 12
< 6
< 8
< 14
< 6
< 5 33
< 10 04/12/2024 04/12/2024 5
7
< 13
< 7
< 17
< 7
< 14
< 11
< 8
< 7 34
< 9 07/12/2024 07/12/2024 3
3
< 7
< 4
< 7
< 4
< 7
< 5
< 4
< 3 14
< 6 10/11/2024 10/11/2024 6
7
< 11
< 7
< 15
< 7
< 13
< 11
< 9
< 7 31
< 12
Annual Radiological Environmental Operating Report YEAR: 2024 Page 64 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 22, Semi-Annual Fish Gamma Isotopic (pCi/kg Wet +/- 2 Sigma)
Station Collection Dates Mn-54 Co-58 Fe-59 Co-60 Zn-65 Nb-95 Zr-95 Cs-134 Cs-137 Ba-140 La-140 D-28 Black Buffalo 06/03/2024
< 44 40 101 72 80 45 80 45
< 44
< 215
< 74 Common Carp 06/03/2024
< 50 58 91 57 106 59 85 57
< 58
< 284
< 104 Black Buffalo 09/24/2024
< 79 101 186 60 196 98 157 80
< 78
< 893
< 261 Common Carp 09/24/2024
< 67 77 154 70 168 83 119 77
< 71
< 675
< 229 D-46 Black Buffalo 06/03/2024
< 50 48 97 47 90 41 80 49
< 41
< 227
< 71 Common Carp 06/03/2024
< 34 37 85 49 88 32 57 46
< 42
< 172
< 49 Common Carp 09/24/2024
< 67 66 158 55 147 83 137 68
< 69
< 773
< 236 Largemouth Bass 09/24/2024
< 68 69 135 59 144 83 134 71
< 71
< 815
< 176
Annual Radiological Environmental Operating Report YEAR: 2024 Page 65 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 23, Semi-Annual Shoreline Sediment Gamma Isotopic (pCi/kg Dry +/- 2 Sigma)
Station Collection Dates Mn-54 Co-58 Fe-59 Co-60 Zn-65 Nb-95 Zr-95 Cs-134 Cs-137 Ba-140 La-140 D-27 05/15/2024 69
< 63 138 102 144
< 65
< 111 82 84 308 69 10/16/2024 122
< 83 205 115 272
< 104
< 161 117 115 411 138
Annual Radiological Environmental Operating Report YEAR: 2024 Page 66 of 76 Company: Constellation Plant: Dresden Clean Energy Center
, Cross Check Intercomparison 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. Intercomparison 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.
Teledyne Brown Engineering Inc. (TBE) participated in the following proficiency testing studies provided by Eckert Ziegler Analytics, DOEs Mixed Analyte Performance Evaluation Program (MAPEP), and/or Environmental Resource Associates (ERA) in 2024. The Laboratorys intercomparison program results for 2024 are summarized below.
For the TBE laboratory, 152 out of 167 analyses performed met the specified acceptance criteria. Fifteen analyses did not meet the specified acceptance criteria and were addressed through the TBE Corrective Action Program. A summary is found below:
I. NCR 24-02: ERA March MRAD-40 study with Air Particulate AM-241 evaluated as Not Acceptable. TBE reported 38.8 pCi/filter and the known value returned at 55.0 pCi/filter (range 39.3-73.3). The root cause investigation determined that the sample was not logged into the system correctly and therefore not prepared with the required tracer. To correct and prevent recurrence, personnel involved are to utilize a template to ensure all analyses are logged as required and the QA Manager will perform sample log review as a back up to ensure accuracy. Acceptable results returned in a later sample study, supporting effectiveness of corrective action.
II.
NCR 24-03: ERA March MRAD-40 air particulate study GR-B evaluated as Not Acceptable. TBE reported 42.1 pCi/filter and the known value returned at 22.2 pCi/filter (range 13.5-33.5). The root cause investigation determined that alpha-to-beta crosstalk was more significant than normal which caused the beta activity to report falsely high data. To correct and prevent recurrence, personnel involved are to adjust the alpha-to-beta crosstalk via correction calculation measures when high alpha activities are observed. Acceptable results returned in a later sample study, supporting effectiveness of corrective action.
III.
NCR 24-05: ERA April RAD-137 water study GR-A evaluated as Not Acceptable.
TBE reported 35.2 pCi/L and the known value returned at 52.6 pCi/L (range 39.6-65.6). The root cause investigation determined that the provided samples contained a solids content that was significantly higher than the typical client samples tested by the laboratory. A set aliquot volume for prior ERA samples was used and not adjusted to account for the sudden increase in solid content. To correct and prevent recurrence, new sample types were ordered from ERA that used Am-241 to better reflect client sample testing and acceptable results were achieved. Acceptable results returned in a later sample study, supporting effectiveness of corrective action.
IV.
NCR 24-06: E&Z Analytics March E14092 air particulate study Co-60 evaluated as Not Acceptable. TBE reported 168 pCi and the known value returned at 126 pCi.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 67 of 76 Company: Constellation Plant: Dresden Clean Energy Center Additionally, March E14093 soil Ce-141 evaluated as Not Acceptable. TBE reported 0.106pCi/g and the known value returned at 0.071pCi/g. The root cause investigation was unable to determine any anomaly thus no proposed corrective action. No recurrence has occurred.
V.
CAR 24-02 (CAR 23-31): MAPEP February 24-MaS50 soil study Fe-55 evaluated as Not Acceptable. TBE reported 297 Bg/Kg and the known value returned at 650 Bg/Kb (range 455-845). The root cause investigation suspects that the current analytical procedure is not sufficient to add the interferences added to the sample by MAPEP.
This investigation is still ongoing (See NCR 24-16) as the suggested corrective action did not provide desired results.
VI.
NCR 24-08: MAPEP February 24-MaS50 soil study Ni-63 evaluated as Not Acceptable. TBE reported 1070 Bg/Kg and the known value returned at 1530 Bg/Kb (range 1071-1989). The root cause investigation suspected that the sample contained added interferences that are not typically seen in client samples. All QC efforts associated with the sample were acceptable and no anomalies found, even after reanalysis. To correct and prevent recurrence, samples suspected of additional interferences will include the addition of Ni-59 tracer to determine yield results when calculating results. TBE analytical procedure TBE-2013 was updated to include this change.
VII.
NCR 24-09: MAPEP February 24-MaSU50 urine study Zn-65 evaluated as Not Acceptable. The root cause investigation determined that the sample was spiked lower than TBEs typical detection limit and client requirements. The report was revised by MAPEP indicating Not Evaluated, resulting in this nuclide to not be considered a failure.
VIII.
NCR 24-10: MAPEP February 24-MaW50 water study Tc-99 evaluated as Not Acceptable. TBE reported 9.95Bg/L and the known value returned 7.47Bg/L (range 5.23-9.71). The root cause investigation suspects Thorium interference that was not removed during the column separation process of the analytical procedure; however, it cannot be confirmed as all QC efforts associated with the sample were acceptable and with no anomalies found. To potentially correct and prevent recurrence, an additional rinse step was added to the procedure. Acceptable results returned in a later sample study, supporting effectiveness of corrective action.
IX.
NCR 24-11: MAPEP February 24-RdV50 vegetation study Sr-90 evaluated as Not Acceptable. TBE reported 0.276Bg/sample and the known value returned 0.529Bg/sample (range 0.370-0.688). The root cause investigation determined a laboratory accident resulting in a spilled (loss) of sample. No corrective action was performed as the cause was an unintentional sample spill.
X.
NCR 24-14: ERA September MRAD-41 air particulate study U-234/238 evaluated as Not Acceptable. TBE reported 14.0/14.2 pCi/filter and the known value returned at 31.1/30.9 pCi/filter (range 23.1-36.9). The root cause investigation determined that the laboratory technician placed double the amount of tracer in the sample by error. To correct and prevent recurrence, samples that have been digested/leached with carrier/tracer added will have a label placed over the cap indicating it has already been added. Additionally, the beaker that aliquot is put in should have markings to indicate
Annual Radiological Environmental Operating Report YEAR: 2024 Page 68 of 76 Company: Constellation Plant: Dresden Clean Energy Center carrier/tracer has already been added to the sample.
XI.
NCR 24-15: ERA September MRAD-41 water study Fe-55 evaluated as Not Acceptable. TBE reported 615 pCi/L and the known value returned at 1230 pCi/L (range 723-1790). The root cause is still under investigation.
XII.
NCR 24-16: MAPEP August 24-MaS50 soil study Fe-55 evaluated as Not Acceptable. TBE did not report a value, and the known value returned 780Bg/Kg (range 546-1014). The root cause is still under investigation.
XIII.
NCR 24-17: MAPEP August 24-RdV51 vegetation study Sr-90 evaluated as Not Acceptable. TBE reported 0.95Bg/sample and the known value returned 2.39Bg/sample (range 1.67-3.11). The root cause is still under investigation.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 69 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 24: Analytics Environmental Radioactivity Cross Check Program Teledyne Brown Engineering Environmental Services Month/Year Identification Number Matrix Nuclide Units TBE Reported Value Known Value (a)
Ratio of TBE to Analytics Result Evaluation (b)
March 2024 E14089 Milk Sr-89 pCi/L 79.6 78.2 1.02 A
Sr-90 pCi/L 12.6 11.9 1.06 A
E14090 Milk Ce-141 pCi/L 75.6 85.0 0.89 A
Co-58 pCi/L
-0.069 Not Measured Co-60 pCi/L 139 158 0.88 A
Cr-51 pCi/L 212 230 0.92 A
Cs-134 pCi/L 167 198 0.84 A
Cs-137 pCi/L 158 171 0.93 A
Fe-59 pCi/L 81.1 86.5 0.94 A
I-131 pCi/L 80.9 90.8 0.89 A
Mn-54 pCi/L 173 183 0.95 A
Zn-65 pCi/L 165 176 0.93 A
E14091 Charcoal I-131 pCi 90.1 90.3 1.00 A
E14092 AP Ce-141 pCi 68.1 67.5 1.01 A
Co-58 pCi 1.73 Not Measured Co-60 pCi 168 126 1.34 N(1)
Cr-51 pCi 182 183 0.99 A
Cs-134 pCi 157 157 1.00 A
Cs-137 pCi 132 136.0 0.97 A
Fe-59 pCi 70.3 68.6 1.02 A
Mn-54 pCi 144 145 0.99 A
Zn-65 pCi 125 140 0.89 A
E14093 Soil Ce-141 pCi/g 0.106 0.071 1.48 N(1)
Co-58 pCi/g
-0.005 Not Measured Co-60 pCi/g 0.121 0.133 0.91 A
Cr-51 pCi/g 0.198 0.194 1.02 A
Cs-134 pCi/g 0.206 0.166 1.24 W
Cs-137 pCi/g 0.207 0.209 0.99 A
Fe-59 pCi/g 0.063 0.073 0.87 A
Mn-54 pCi/g 0.140 0.153 0.91 A
Zn-65 pCi/g 0.149 0.148 1.01 A
E14094 AP Sr-89 pCi 83.9 90.6 0.93 A
Sr-90 pCi 11.7 13.8 0.85 A
(a) The Analytics known value is equal to 100% of the parameter present in the standard as determined by gravimetric and/or volumetric measurements made during standard preparation (b) Analytics evaluation based on TBE internal QC limits:
A = Acceptable - reported result falls within ratio limits of 0.80-1.20 W = Acceptable with warning - reported result falls within 0.70-0.80 or 1.20-1.30 N = Not Acceptable - reported result falls outside the ratio limits of < 0.70 and > 1.30 (1) See NCR 24-06
Annual Radiological Environmental Operating Report YEAR: 2024 Page 70 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 24: Analytics Environmental Radioactivity Cross Check Program Contd Teledyne Brown Environmental Services Month/Year Identification Number Matrix Nuclide Units TBE Reported Value Known Value (a)
Ratio of TBE to Analytics Result Evaluation (b)
September 2024 E14095 Milk Sr-89 pCi/L 88.0 92.3 0.95 A
Sr-90 pCi/L 12.4 15.2 0.82 A
E14096 Milk Ce-141 pCi/L 124 124 1.00 A
Co-58 pCi/L 154 150 1.03 A
Co-60 pCi/L 232 236 0.98 A
Cr-51 pCi/L 284 274 1.04 A
Cs-134 pCi/L 180.0 187 0.96 A
Cs-137 pCi/L 126 127 0.99 A
Fe-59 pCi/L 127.0 113 1.12 A
I-131 pCi/L 85.3 89.0 0.96 A
Mn-54 pCi/L 162 162 1.00 A
Zn-65 pCi/L 294 275 1.07 A
E14097 Charcoal I-131 pCi 98.8 92.6 1.07 A
E14098 AP Ce-141 pCi 82.0 76.7 1.07 A
Co-58 pCi 91.0 92.6 0.98 A
Co-60 pCi 180 146 1.23 W
Cr-51 pCi 208 170 1.22 W
Cs-134 pCi 116 116 1.00 A
Cs-137 pCi 83.1 78.9 1.05 A
Fe-59 pCi 75.6 70.2 1.08 A
Mn-54 pCi 101 100 1.01 A
Zn-65 pCi 167 170 0.98 A
E14099 Soil Ce-141 pCi/g 0.224 0.222 1.01 A
Co-58 pCi/g 0.249 0.268 0.93 A
Co-60 pCi/g 0.420 0.423 0.99 A
Cr-51 pCi/g 0.492 0.492 1.00 A
Cs-134 pCi/g 0.278 0.336 0.83 A
Cs-137 pCi/g 0.276 0.295 0.94 A
Fe-59 pCi/g 0.233 0.204 1.14 A
Mn-54 pCi/g 0.279 0.290 0.96 A
Zn-65 pCi/g 0.538 0.494 1.09 A
E14100 AP Sr-89 pCi 79.8 82.7 0.96 A
Sr-90 pCi 12.0 13.6 0.88 A
E14197 Liquid Gr-A (Am241) pCi/L 47.6 50.1 0.95 A
Gr-B (Cs137) pCi/L 248 270 0.92 A
(a) The Analytics known value is equal to 100% of the parameter present in the standard as determined by gravimetric and/or volumetric measurements made during standard preparation (b) Analytics evaluation based on TBE internal QC limits:
A = Acceptable - reported result falls within ratio limits of 0.80-1.20 W = Acceptable with warning - reported result falls within 0.70-0.80 or 1.20-1.30 N = Not Acceptable - reported result falls outside the ratio limits of < 0.70 and > 1.30
Annual Radiological Environmental Operating Report YEAR: 2024 Page 71 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 25: DOEs Mixed Analyte Performance Evaluation Program (MAPEP)
Teledyne Brown Engineering Environmental Services Month/Year Identification Number Matrix Nuclide Units TBE Reported Value Known Value (a)
Acceptance Range Evaluation (b)
February 2024 24-MaS50 Soil Fe-55 Bq/kg 297 650 455 - 845 N(3)
Ni-63 Bq/kg 1070 1530 1071 - 1989 N(4)
Tc-99 Bq/kg 325 336 235 - 437 A
Th-228 Bq/kg 34.6 48.8 34.2 - 63.4 W
Th-230 Bq/kg 49.7 54.0 38.0 - 70.0 A
Th-232 Bq/kg 36.4 45.1 31.6 - 58.6 A
24-MaSU50 Urine Cs-134 Bq/L 1.12 1.36 0.95 - 1.77 A
Cs-137 Bq/L 2.00 2.23 1.56 - 2.90 A
Co-57 Bq/L 1.06 1.26 0.88 - 1.64 A
Co-60 Bq/L 2.26 2.38 1.67 - 3.09 A
K-40 Bq/L
-1.80 NR Mn-54 Bq/L 1.44 1.51 1.06 - 1.96 A
U-234 Bq/L 0.00101 (1)
A U-238 Bq/L 0.00228 (1)
A Zn-65 Bq/L
-0.42 0.84 0.59 - 1.09 NE(5) 24-MaW50 Water Ni-63 Bq/L 0.338 0.80 (2)
A Tc-99 Bq/L 9.95 7.47 5.23 - 9.71 N(6) 24-RdV50 Vegetation Cs-134 Bq/sample 2.80 3.67 2.57 - 4.77 W
Cs-137 Bq/sample 2.21 2.57 1.80 - 3.34 A
Co-57 Bq/sample 2.23 2.53 1.77 - 3.29 A
Co-60 Bq/sample 2.42 2.96 2.07 - 3.85 A
Mn-54 Bq/sample 0.033 (1)
A Sr-90 Bq/sample 0.276 0.529 0.370 - 0.688 N(7)
Zn-65 Bq/sample 6.83 8.02 5.61 - 10.43 A
(a) The MAPEP known value is equal to 100% of the parameter present in the standard as determined by gravimetric and/or volumetric measurements made during standard preparation (b) DOE/MAPEP evaluation:
A = Acceptable - reported result falls within ratio limits of 0.80-1.20 W = Acceptable with warning - reported result falls within 0.70-0.80 or 1.20-1.30 N = Not Acceptable - reported result falls outside the ratio limits of < 0.70 and > 1.30 (1) False positive test (2) Sensitivity evaluation (3) See CAR 23 Analyte not on XCHK list (4) See NCR 24-08 (5) Not Evaluated (6) See NCR 24-10 (7) See NCR 24-11 (8) Not Reported (9) See NCR 24-16 (10) See NCR 24-17
Annual Radiological Environmental Operating Report YEAR: 2024 Page 72 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 25: DOEs Mixed Analyte Performance Evaluation Program (MAPEP) Contd Teledyne Brown Engineering Environmental Services Month/Year Identification Number Matrix Nuclide Units TBE Reported Value Known Value (a)
Acceptance Range Evaluation (b)
August 2024 24-MaS51 Soil Fe-55 Bq/kg (8) 780 546 - 1014 N(9)
Ni-63 Bq/kg 1140.00 1450.00 1015 - 1885 W
Tc-99 Bq/kg 155.00 171.00 120 - 222 A
Th-228 Bq/kg 38.00 43.30 30.3 - 56.3 A
Th-230 Bq/kg 46.10 44.00 30.8 - 57.2 A
Th-232 Bq/kg 38.90 42.60 29.8 - 55.4 A
24-MaW51 Water Ni-63 Bq/L 0.60 (1)
A Tc-99 Bq/L 11.90 11.20 7.8 - 14.6 A
24-RdV51 Vegetation Cs-134 Bq/sample 3.12 2.89 2.02 - 3.76 A
Cs-137 Bq/sample 2.18 1.91 1.34 - 2.48 A
Co-57 Bq/sample 0.00 (1)
A Co-60 Bq/sample 2.24 2.01 1.41 - 2.61 A
Mn-54 Bq/sample 3.76 3.53 2.47 - 4.59 A
Sr-90 Bq/sample 0.95 2.39 1.67 - 3.11 N(10)
Zn-65 Bq/sample 10.30 9.13 6.39 - 11.87 A
(a) The MAPEP known value is equal to 100% of the parameter present in the standard as determined by gravimetric and/or volumetric measurements made during standard preparation (b) DOE/MAPEP evaluation:
A = Acceptable - reported result falls within ratio limits of 0.80-1.20 W = Acceptable with warning - reported result falls within 0.70-0.80 or 1.20-1.30 N = Not Acceptable - reported result falls outside the ratio limits of < 0.70 and > 1.30 (1) False positive test (2) Sensitivity evaluation (3) See CAR 23 Analyte not on XCHK list (4) See NCR 24-08 (5) Not Evaluated (6) See NCR 24-10 (7) See NCR 24-11 (8) Not Reported (9) See NCR 24-16 (10) See NCR 24-17
Annual Radiological Environmental Operating Report YEAR: 2024 Page 73 of 76 Company: Constellation Plant: Dresden Clean Energy Center Table 26: ERA Environmental Radioactivity Cross Check Program Teledyne Brown Engineering Environmental Services Month/Year Identification Number Matrix Nuclide Units TBE Reported Value Known Value (a)
Acceptance Limits Evaluation (b)
March 2024 MRAD-40 Water Am-241 pCi/L 101 139 95.4 - 178 A
Fe-55 pCi/L 2185 2480 1460- 3610 A
Pu-238 pCi/L 62.0 70.4 42.3 - 91.2 A
Pu-239 pCi/L 61.2 76.5 47.3 - 94.3 A
Soil Am-241 pCi/kg NR 1880 1020 - 2660 Pu-238 pCi/kg 667 512 255 - 778 A
Pu-239 pCi/kg 562 545 297 - 784 A
Sr-90 pCi/kg 4050 3630 1130 - 5650 A
U-234 pCi/kg 3040 4360 2040 - 5710 A
U-238 pCi/kg 3270 4320 2370 - 5800 A
AP Am-241 pCi/filter 38.8 55.0 39.3 - 73.3 N(1)
Fe-55 pCi/filter 387 386 141 - 616 A
Pu-238 pCi/filter 45.9 41.1 31.0 - 50.5 A
Pu-239 pCi/filter 54.9 56.1 41.9 - 67.7 A
U-234 pCi/filter 11.1 11.6 8.60 - 13.6 A
U-238 pCi/filter 12.8 11.5 8.68 - 13.7 A
GR-A pCi/filter 116 95.9 50.1 - 158 A
GR-B pCi/filter 42.1 22.2 13.5 - 33.5 N(2)
April 2024 RAD-137 Water Ba-133 pCi/L 62.8 65.9 50.1 - 81.7 A
Cs-134 pCi/L 51.0 57.8 42.8 - 72.8 A
Cs-137 pCi/L 153 186 149 - 223 A
Co-60 pCi/L 92.1 98.8 79.7 - 118 A
Zn-65 pCi/L 208 240 188 - 292 A
GR-A pCi/L 35.2 52.6 39.6 - 65.6 N(3)
GR-B pCi/L 49 46.5 33.9 - 59.1 A
U-Nat pCi/L 56.0 59.3 52.8-65.8 A
H-3 pCi/L 19,000 21,300 18,200 - 24,400 A
Sr-89 pCi/L 48.9 52.2 37.8 - 66.6 A
Sr-90 pCi/L 32.6 37.6 32.0 - 43.2 A
I-131 pCi/L 21.8 25.1 21.7 - 28.5 A
(a) The ERA known value is equal to 100% of the parameter present in the standard as determined by gravimetric and/or volumetric measurements made during standard preparation.
(b) ERA evaluation:
A = Acceptable - Reported value falls within the Acceptance Limits N = Not Acceptable - Reported value falls outside of the Acceptance Limits (1) See NCR 24-02 (2) See NCR 24-03 (3) See NCR 24-05 (4) See NCR 24-15 (5) See NCR 24-14
Annual Radiological Environmental Operating Report YEAR: 2024 Page 74 of 76 Company: Constellation Plant: Dresden Clean Energy Center
, Environmental Direct Radiation Dosimetry Results Monitoring Location Quarterly
- Baseline, BQ (mrem)
BQ +
MDDQ Normalized Quarterly Monitoring Data, MQ Quarterly Facility Dose, Annual
- Baseline, BA (mrem)
BA +
MDDA Annual Monitoring Data, MA (mrem)
Annual Facility
- Dose, FA=MA-BA FQ=MQ-BQ (mrem, or ND if (mrem)
(mrem)
(mrem, or ND if FQ MDDQ)
(mrem)
FA MDDA) 1 2
3 4
1 2
3 4
D-01 27.7 40.5 17.4 21.3 19.7 23.7 ND ND ND ND 110.7 155.1 82.1 ND D-02 28.8 41.6 17.7 22.6 16.5 22.5 ND ND ND ND 115.4 159.8 79.4 ND D-03 23.9 36.7 21.1 18.5 18.7 21.2 ND ND ND ND 95.6 140 79.4 ND D-04 27.4 40.2 19.4 20.6 19.7 22.4 ND ND ND ND 109.7 154.1 82.1 ND D-07 26.7 39.5 22.8 20.8 17.1 23.4 ND ND ND ND 106.6 151 84 ND D-08 24.4 37.2 22.1 20.4 19 23.8 ND ND ND ND 97.8 142.2 85.3 ND D-10 28.6 41.4 23.1 21.9 20.2 23.4 ND ND ND ND 114.5 158.9 88.6 ND D-12 23.7 36.5 18.8 21.6 17 23.7 ND ND ND ND 90.2 134.6 81 ND D-14 23.5 36.3 20.4 17.9 17.3 22.6 ND ND ND ND 93.8 138.2 78.2 ND D-45 23.2 36 23.8 21.6 20.1 24.9 ND ND ND ND 92.9 137.3 90.4 ND D-53 27.5 40.3 15.8 18.7 18.3 21.2 ND ND ND ND 110 154.4 73.9 ND D-55 27.2 40 18.2 20.3 17.4 21 ND ND ND ND 108.8 153.2 76.9 ND D-56 25.3 38.1 17.3 19.1 16.1 21 ND ND ND ND 101.1 145.5 73.5 ND D-58 26.5 39.3 16.2 15.8 15.5 18.9 ND ND ND ND 105.9 150.3 66.4 ND D-101 26.6 39.4 22.3 19.8 20.7 24.2 ND ND ND ND 106.5 150.9 87 ND D-102 28.6 41.4 26.7 23.2 20.4 25.4 ND ND ND ND 114.3 158.7 95.7 ND D-103 26.4 39.2 20.5 22.7 19.4 21.9 ND ND ND ND 105.6 150 84.4 ND D-104 28.3 41.1 23.5 22.2 17.6 22.6 ND ND ND ND 107.4 151.8 86 ND D-105 27.1 39.9 20 22.9 20.8 23.4 ND ND ND ND 108.6 153 87.1 ND D-106 24.1 36.9 14.8 14.9 14.1 19.1 ND ND ND ND 91.7 136.1 62.9 ND MDDQ = Quarterly Minimum Differential Dose = 12.8 mrem MDDA = Annual Minimum Differential Dose = 44.4 mrem ND = Not Detected, where MQ (BQ+MDDQ) or MA (BA+MDDA)
Annual Radiological Environmental Operating Report YEAR: 2024 Page 75 of 76 Company: Constellation Plant: Dresden Clean Energy Center Monitoring Location Quarterly
- Baseline, BQ (mrem)
BQ + MDDQ Normalized Quarterly Monitoring Data, MQ Quarterly Facility Dose, Annual
- Baseline, BA (mrem)
BA +
MDDA Annual Monitoring Data, MA (mrem)
Annual Facility
- Dose, FA=MA-BA FQ=MQ-BQ (mrem, or ND if (mrem)
(mrem)
(mrem, or ND if FQ MDDQ)
(mrem)
FA MDDA) 1 2
3 4
1 2
3 4
D-107 23.8 36.6 19 16.9 18.4 18.9 ND ND ND ND 95.3 139.7 73.1 ND D-108 26.8 39.6 18.6 19.9 (1) 21.6 ND ND (1)
ND 107.3 151.7 80.1 ND D-109 27 39.8 19.2 22.8 19.1 24.1 ND ND ND ND 108.2 152.6 85.2 ND D-110 31.1 43.9 23 24.2 23.2 29.9 ND ND ND ND 124.6 169 100.3 ND D-111 28.6 41.4 22.4 22.7 19.7 23.9 ND ND ND ND 103.1 147.5 88.6 ND D-112A 25.3 38.1 16.1 17.5 16.9 21.9 ND ND ND ND 101.2 145.6 72.4 ND D-113 25.1 37.9 21.7 19.2 19.6 22.4 ND ND ND ND 95.5 139.9 82.9 ND D-114 24.6 37.4 20 16.2 17.4 19.2 ND ND ND ND 98.2 142.6 72.7 ND D-115 27.5 40.3 23.2 21.5 21.8 22.4 ND ND ND ND 110.2 154.6 88.8 ND D-116 29.4 42.2 24.6 23.8 22.3 27 ND ND ND ND 117.7 162.1 97.7 ND D-201 30.8 43.6 22.2 23 21.2 27.2 ND ND ND ND 110.8 155.2 93.5 ND D-202 27.6 40.4 23 19.3 21.8 23.8 ND ND ND ND 104.9 149.3 87.9 ND D-203 26.2 39 20.1 20.1 19.5 23.4 ND ND ND ND 94.4 138.8 83.1 ND D-204 24.4 37.2 19.3 19.3 17 20.2 ND ND ND ND 97.8 142.2 75.8 ND D-205 23.3 36.1 22.2 21.6 20.5 21.6 ND ND ND ND 93.4 137.8 85.9 ND D-206 26.6 39.4 23.8 20 18.6 21 ND ND ND ND 101.1 145.5 83.4 ND D-207 24.8 37.6 18.6 17.1 14.9 19.5 ND ND ND ND 99.1 143.5 70.1 ND D-208 23 35.8 18 17.9 16.2 19 ND ND ND ND 91.9 136.3 71.1 ND D-209 23.1 35.9 17.5 18.5 13.2 22 ND ND ND ND 92.4 136.8 71.1 ND MDDQ = Quarterly Minimum Differential Dose = 12.8 mrem MDDA = Annual Minimum Differential Dose = 44.4 mrem ND = Not Detected, where MQ (BQ+MDDQ) or MA (BA+MDDA)
(1) See Sample Deviations Table (Table 9)
Annual Radiological Environmental Operating Report YEAR: 2024 Page 76 of 76 Company: Constellation Plant: Dresden Clean Energy Center MDDQ = Quarterly Minimum Differential Dose = 12.8 mrem MDDA = Annual Minimum Differential Dose = 44.4 mrem ND = Not Detected, where MQ (BQ+MDDQ) or MA (BA+MDDA)
Monitoring Location Quarterly
- Baseline, BQ (mrem)
BQ + MDDQ Normalized Quarterly Monitoring Data, MQ Quarterly Facility Dose, Annual
- Baseline, BA (mrem)
BA +
MDDA Annual Monitoring Data, MA (mrem)
Annual Facility
- Dose, FA=MA-BA FQ=MQ-BQ (mrem, or ND if (mrem)
(mrem)
(mrem, or ND if FQ MDDQ)
(mrem)
FA MDDA) 1 2
3 4
1 2
3 4
D-210 26.1 38.9 23.3 23.3 21.6 22.1 ND ND ND ND 104.6 149 90.3 ND D-211 27.7 40.5 20.5 20.2 19.4 23.9 ND ND ND ND 111 155.4 83.9 ND D-212 24.5 37.3 17.8 18 16.7 19 ND ND ND ND 98 142.4 71.5 ND D-213 23.1 35.9 19.5 16.7 15.6 17.9 ND ND ND ND 92.6 137 69.6 ND D-214 31 43.8 21 21.5 17.4 23.2 ND ND ND ND 123.8 168.2 83 ND D-215 29.9 42.7 21.5 26.8 22 25.4 ND ND ND ND 119.8 164.2 95.7 ND D-216 28 40.8 20.1 21 19 20.9 ND ND ND ND 106.3 150.7 80.9 ND