ML25113A181
| ML25113A181 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf  |
| Issue date: | 04/23/2025 |
| From: | Hardy J Entergy Operations |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| GNR02025-00010 | |
| Download: ML25113A181 (1) | |
Text
~
entergy GNRO2025-00010 April 23, 2025 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Entergy Operations, Inc.
P.O. Box 756 Port Gibson, Mississippi 39150 Jeffery Hardy Manager Regulatory Assurance Grand Gulf Nuclear Station Tel : 802-380-5124 GGNS TS 5.6.2
SUBJECT:
Grand Gulf Nuclear Station Annual Radiological Environmental Operating Report (AREOR)
Grand Gulf Nuclear Station, Unit 1 Docket No. 50-416 License No. NPF-29 In accordance with Grand Gulf Nuclear Station Unit 1 Technical Specification 5.6.2, attached is the Annual Radiological Environmental Operating Report (AREOR) for the time-period of January 1, 2024 through December 31, 2024.
There are no commitments contained in this submittal. If you have any questions or need additional information, please contact me at 802-380-5124.
SinceQA \\-\\,
JH/ram 1
Attachment:
1, Annual Radiological Environmental Operating Report
GNRO2025-00010 Page 2 of 2 cc:
NRC Senior Resident Inspector Grand Gulf Nuclear Station Port Gibson, MS 39150 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 GNRO2025-00010 Annual Radiological Environmental Operating Report
S) entergy Grand Gulf Nuclear Station 2024 Annual Radiological Environmental Operating Report Document Number: GNRO 2025-00010
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 1 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station 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.............................................................................................. 15 7.0 REPORTING LEVELS FOR RADIOACTIVITY CONCENTRATIONS IN ENVIRONMENTAL SAMPLES................................................................................................. 17 8.0 SAMPLING PROGRAM, PROGRAM MODIFICATION AND INTEPRETATION OF RESULTS................................................................................................................................ 18 8.1 Environmental Direct Radiation Dosimetry Results....................................................... 18 8.2 Air Particulate and Radioiodine Sample Results........................................................... 20 8.3 Waterborne Sample Results......................................................................................... 21 8.4 Ingestion Pathway Sample Results............................................................................... 23 9.0 LAND USE CENSUS............................................................................................................... 24 10.0 SAMPLE DEVIATIONS, ANOMALIES AND UNAVAILABILITY................................................ 25 11.0 OTHER SUPPLEMENTAL INFORMATION............................................................................. 26 11.1 NEI 07-07 Onsite Radiological Groundwater Monitoring Program................................. 26 11.2 Independent Spent Fuel Storage Installation (ISFSI) Monitoring Program.................... 26 11.3 lnterlaboratory Comparison Results.............................................................................. 26 11.4 Corrections to Previous Reports................................................................................... 26 12.0 BIBLIOGRAPHY...................................................................................................................... 27 TABLES Table 1, Exposure Pathway - Airborne................................................................................................... 8 Table 2, Exposure Pathway - Direct Radiation...................................................................................... 9 Table 3, Exposure Pathway - Waterborne........................................................................................... 10 Table 4, Exposure Pathway - Ingestion............................................................................................... 12 Table 5, REMP Sampling Locations - Direct Radiation........................................................................ 13 Table 6, Reporting Levels for Radioactivity Concentrations in Environmental Samples....................... 17 Table 7, Maximum Values for the Limit of Detection............................................................................ 17 Table 8: Direct Radiation Annual Results............................................................................................. 18 Table 9: Land Use Census - Nearest Receptors within 5 miles........................................................... 25 Table 1 O: Sample Deviation Summary................................................................................................. 26 Table 11, Air Particulate Data Summary Table.................................................................................... 36 Table 12, Radioiodine Cartridge Data Table Summary........................................................................ 38 Table 13, Air Gamma Quarterly Composite......................................................................................... 40
Annual Radiological Environmental Operating Report I YEAR: 2024 I
Page 2 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station Table 14, Thermoluminescent Dosimeters-Inner Ring....................................................................... 41 Table 15, Thermoluminescent Dosimeters - Outer Ring...................................................................... 42 Table 16, Thermoluminescent Dosimeters - Special Interest Areas.................................................... 42 Table 17, Thermoluminescent Dosimeters - Control........................................................................... 42 Table 18, Surface Water - Gamma...................................................................................................... 43 Table 19, Surface Water - Tritium...................................................................................................... 45 Table 20, Drinking Water - Gamma, l-131............................................................................................ 47 Table 21, Drinking Water-Tritium....................................................................................................... 48 Table 22, Sediment.............................................................................................................................. 48 Table 23, Fish...................................................................................................................................... 49 Table 24, Food Products...................................................................................................................... 49 Table 25, Special Samples, Surface Water-Gamma Isotopic............................................................ 51 Table 26, Special Samples, Meat........................................................................................................ 52 FIGURES Figure 1, Potential exposure pathways to Members of the Public due to Plant Operations [7]............... 6 Figure 2, REMP Sample Locations (Near Field/Site Boundary)........................................................... 15 Figure 3, REMP Sample Locations (Far Field)..................................................................................... 16 Figure 4, Air Particulate: Analysis for Gross Beta, Average for All Indicator vs. Control Location......... 20 Figure 5, Surface Water Tritium Results.............................................................................................. 21 ATTACHMENTS, Data Table Summary.................................................................................................... 29, Complete Data Table for All Analysis Results Obtained In 2024................................... 35, Cross Check lntercomparison Program......................................................................... 53, Environmental Direct Radiation Dosimetry Results....................................................... 59
Annual Radiological Environmental Operating Report I YEAR: 2024 I
Page 3 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station 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 I YEAR: 2024 I
Page 4 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station
- 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.
NIA: 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.
OSLO: 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
Grand Gulf Nuclear Station (GGNS) 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 GGNS 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) and GGNS Technical Specification 5.6.2. 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 I YEAR: 2024 I Page 5 of 60 Company: Enterav Operations, Inc.
I Plant: Grand Gulf Nuclear Station 2.1 The Annual Radiological Environmental Operating Report (AREOR) provides data obtained through analyses of environmental samples collected at GGNS for the reporting period of January 1st through December 31st, 2024. During that time period 657 analyses were performed on 619 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 GGNS, did not result in detection of plant related radionuclides in the environment.
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 GGNS. 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-?,
actinium-228 (present as a decay product of radium-228), and radium-226.
Additionally, some relatively long-lived anthropogenic radioisotopes, such as strontium-90 and cesium-137, are also seen in some REMP samples; these radionuclides exist in measurable quantities throughout the world as a result of fallout from historic atmospheric nuclear weapons testing. Detailed information on the exposure of the U.S. population to ionizing radiation can be found in NCRP Report No. 160 [1].
Annual Radiological Environmental Operating Report I YEAR: 2024 I
Page 6 of 60 Company: EnterQV Operations, Inc.
I Plant: Grand Gulf Nuclear Station
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].
- . 0 po ition Gaseous effiuents
<2,y=
c::>
\\ Depo ition
- * *. \\0/
Soil
- ***** Inge t' Livestock products
- Radiation o
- Radionuclides
- .. * :Behavior of radionuclides Figure 1, Potential exposure pathways to Members of the Public due to Plant Operations [7]
Quality assurance aspects of the sampling program and 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 Mississippi State Department of Health (MSDH), Division of Radiological Health monitoring program, GGNS 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. MSDH and the GGNS REMP entail similar radiological environmental monitoring program requirements. These programs include collecting air samples and splitting or sharing sample media such as water, sediment, and fish. Both programs have obtained similar results over previous years.
Annual Radiological Environmental Operating Report I YEAR: 2024 I
Page 7 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station 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 Grand Gulf Nuclear Station is a commercial nuclear power plant that achieved initial criticality in 1982. The facility is located in Claiborne County, Mississippi, on the east side of the Mississippi River approximately 5 miles northwest of Port Gibson, Mississippi, 25 miles south of Vicksburg and 37 miles north-northeast of Natchez, Mississippi. Grand Gulf Nuclear Station is a BWR-6 boiling water reactor with a rated power level of 4408 megawatts thermal. GGNS established the REMP in 1978 prior to the station becoming operational (1985) to provide data on background radiation and radioactivity normally present in the area.
GGNS 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, Exposure Pathway - Airborne Table 2, Exposure Pathway - Direct Radiation Table 3, Exposure Pathway - Waterborne Table 4, Exposure Pathway - Ingestion Table 5, REMP Sampling Locations - Direct Radiation Figure 2, REMP Sample Locations (Near Field/Site Boundary)
Figure 3, REMP Sample Locations (Far Field)
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 8 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station 5.0 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM REQUIREMENTS Table 1, Exposure Pathway - Airborne Requirement Sample Location Description, Sampling Collection/
Type and Frequency of Analyses Distance, and Direction Frequency RADIOIODINE AND PARTICULATES 1 sample close to the SITE AS-7 (Sector H, 0.5 miles) -
BOUNDARY having the highest South-southeast of GGNS at the calculated annual average ground IBEW Union Hall level D/Q_
RADIOIODINE AND PARTICULATES 1 sample from the vicinity of a AS-1 (Sector G, 5.5 miles) -
community having the highest Southeast of GGNS at the Port
. Radioiodine Canisters 131 analysis every 7 calculated annual average ground Gibson City Barn days level O/Q.
7 days, or more frequently. Air Particulate - Gross beta radioactivity if required by dust loading.
analysis following filter change RADIOIODINE AND PARTICULATES
. Air Particulate - Gamma Isotopic composite 1 sample from the vicinity of a AS-20 (Sector L, 0.9 miles) -
(by location) every 92 days community having the highest South-southeast of GGNS at the calculated annual average ground former Glodjo residence level D/Q.
RADIOIODINE AND PARTICULATES AS-3 (Sector B, 18 miles)-
1 sample from a control location 15 -
30 km distance.
North of the Vicksburg Airport
Annual Radiological Environmental Operating Report I YEA~R: 2024 J __ Page 9 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station Table 2, Exposure Pathway - Direct Radiation Requirement Sample Location Description, Sampling Collection/
Type and Frequency of Analyses Distance, and Direction Frequency Direct Radiation 16 stations with two or more dosimeters or one instrument for measuring and recording dose rate continuously. The stations will be placed in accessible sectors alternating between inner and outer ring locations:
- 1) an inner ring of stations in the general areas of the SITE BOUNDARY
- 2) an outer ring approximately 3 to See Table 5 92 days Gamma dose; 92 days 5 miles from the site.
8 additional stations should be placed in special interest areas such as population centers, nearby residences, schools, and in 1 or 2 areas to serve as control stations.
5 additional stations will be placed in locations in the general area of the site boundary to supplement the inner ring monitoring locations.
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 10 of 60 Com~: Entergy Operations, Inc.
j Plant: Grand Gulf Nuclear Station Table 3, Exposure Pathway-Waterborne Requirement Sample Location Description, Sampling Collection/
Type and Frequency of Distance, and Direction Frequency Analyses MRUP (Sector R, Radius 1.8 Miles) -
At least 4500 ft upstream of the GGNS discharge point into the Mississippi SURFACE WATER River to allow adequate mixing of the Mississippi and Big Black Rivers.
Gamma isotopic and tritium 1 sample upstream and 1 sample 92 days downstream.
MRDOWN (Sector N, Radius 1.6 analysis; 92 days Miles) - At least 5000 ft downstream of the GGNS discharge point in the Mississippi River near Radial Well No.
- 1.
MRDOWN (Sector P, Radius 1.3 Miles) 1 sample downstream during a Liquid
- Downstream of the GGNS discharge 366 days Gamma isotopic and tritium Radwaste Discharge.
point in the Mississippi River near analysis; 366 days Radial Well No. 5.
1 sample from Outfall 007 OUTFALL 007 (Sector N, Radius 0.2 31 days Tritium; 31 days Miles) - Storm Drain System PGWELL (Sector G, Radius 5.0 Miles)
- Port Gibson Wells - Taken from distribution system or one of the five GROUNDWATER wells.
366 days Gamma isotopic and tritium Samples from 2 sources CONSTWELL (Sector Q, Radius 0.4 analysis; 366 days Miles) - GGNS Construction Water Well - Taken from distribution system or the well.
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 11 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station Table 3, Exposure Pathway - Waterborne SEDHAM (Sector N, Radius 1.6 Miles) -
Downstream of the GGNS discharge point SEDIMENT FROM SHORELINE in the Mississippi River near Hamilton Lake 1 sample from downstream area and 1 outlet 366 days Gamma isotopic; 366 days sample from upstream area)
SEDCONT (Minimum of 100 yds) -
Upstream of the GGNS discharge point in the Mississippi River.
Annual Radiological Environmental Operating Report j YEAR: 2024 j
Page 12 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station Table 4, Exposure Pathway - Ingestion Requirement Sample Location Description, Distance, and Sampling Collection/
Type and Frequency of Direction Frequency Analyses MILK If commercially available, 1 sample Currently, no available milking animals within 8 km of GGNS.
from milking animals within 8 km Gamma isotopic and 1-131; distant 92 days when required 92 days 1 sample from milking animals at a ALCONT (Sector K, Radius 10.5 Miles) - Located control location >8 km distant when an South-southwest of GGNS at Alcorn State indicator location exists.
University. (Control)
FISH AND INVERTEBRATES 1 sample in vicinity of GGNS discharge FISH DOWN - Downstream of the GGNS discharge point into the Mississippi River point 366 days Gamma isotopic on edible FISH UP - Upstream of the GGNS discharge point portions; 366 days 1 sample uninfluenced by GGNS into the Mississippi River uninfluenced by plant discharge operations.
FOOD PRODUCTS 1 sample of broad leaf vegetation grown VEG-J (Sector J, Radius 0.4 Miles) - South of in one of two different offsite locations GGNS near former Training Center on Bald Hill with highest anticipated annual average Road.
ground level D/Q if milk sampling is not 92 days when available Gamma isotopic and 1-131 ;
perfomied.
92 days 1 sample of similar vegetation grown 15 VEG-CONT (Sector K, Radius 10.5 Miles) - Alcorn State University south-southwest of GGNS when
- 30 km distant if milk sampling is not available, otherwise a location 15-30 km distant perfomied.
(Control)
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 13 of 60 Company: Entergy Operations, Inc.
/ Plant: Grand Gulf Nuclear Station Table 5, REMP Sampling Locations - Direct Radiation Site#
Location Type Sector Distance (Miles)
Description M-01 Special Interest E
3.5 Across the road from Lake Claiborne Entry Gate M-07 Special Interest G
5.5 AS-1 PG, Port Gibson City Barn M-09 Special Interest D
3.5 Warner Tully Y-Camp M-10 Special Interest A
1.5 Grand Gulf Military Park M-14 Control B
18 AS361VA, Hwy 61, North of Vicksburg Airport M-16 Inner A
0.9 Meteorological Tower M-19 Inner E
0.5 Eastern SITE BOUNDARY Property line, North-Northeast of HWSA M-21 Inner J
0.4 Near Former Training Center Building on Bald Hill Road M-22 Inner G
0.5 Former RR Entrance Crossing On Bald Hill Road M-23 Inner Q
0.5 Gin Lake Road 50 Yards North of Heavy Haul Road on Power Pole M-25 Inner N
1.6 Radial Well Number 1 M-28 Inner L
0.9 Bald Hill Road M-33 Control p
12.5 Newellton, Louisiana Water Tower M-36 Outer p
5 Curve on HW 608, Point Nearest GGNS at Power Pole M-38 Special M
9.5 Lake Bruin State Park, Entrance Road M-39 Special M
13 St. Joseph, Louisiana, Auxiliary Water Tank
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 14 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station Table 5, REMP Sampling Locations - Direct Radiation Site#
Location Type Sector Distance (Miles)
Description M-40 Outer M
2.3 Headly Drive, Near River Port Entrance M-48 Outer K
4.8 0.4 Miles South on Mont Gomer Road on West Side M-49 Outer H
4.5 Fork in Bessie Weathers Road/Shaifer Road M-50 Outer B
5.3 Panola Hunting Club Entrance M-55 Outer D
5 Near lngelside Karnac Ferry Road/Ashland Road Intersection M-57 Outer F
4.5 Hwy 61, Behind the Welcome to Port Gibson Sign at Glensdale Subdivision M-94 Inner R
0.8 Near Meteorological Tower M-95 Inner F
0.5 Spoils Area, fence of old storage area, near entrance gate M-96 Inner B
0.7 North Gate Fence M-97 Inner D
0.8 Grand Gulf Road entrance gate to spoils area M-98 Inner H
0.5 Bald Hill Road, across from Union Hall, in curve M-99 Inner K
0.4 North Fence of old Ball Field near utility pole M-100 Inner C
0.6 Grand Gulf Road
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 15 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station 6.0 MAPS OF COLLECTION SITES i:
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Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 16 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station I
See Figure 2
...J I Figure 3, REMP Sample Locations (Far Field)
Annual Radiological Environmental Operating Report I YEAR: 2024 l Page 17 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station 7.0 REPORTING LEVELS FOR RADIOACTIVITY CONCENTRATIONS IN ENVIRONMENTAL SAMPLES Table 6, Reporting Levels for Radioactivity Concentrations in Environmental Samples Air Particulates Fish (pCi/Kg-Food Products Radionuclide Water (pCi/L) or Gases Milk (pCi/L)
(pCi/m3) wet)
(pCi/Kg-wet)
H-3 20,000 (1)
NIA N/A NIA NIA Mn-54 1,000 NIA 30,000 NIA NIA Fe-59 400 NIA 10,000 NIA NIA Co-58 1,000 NIA 30,000 NIA NIA Co-60 300 NIA 10,000 NIA NIA Zn-65 300 NIA 20,000 NIA NIA Zr-Nb-95 400 NIA NIA NIA NIA 1-131 2
0.9 NIA 3
100 Cs-134 30 10 1,000 60 1,000 Cs-137 50 20 2,000 70 2,000 Ba-La-140 200 NIA NIA 300 NIA Table 7, Maximum Values for the Limit of Detection Water Air Particulates Fish Milk Food Products Sediment Radionuclide (pCi/L) or Gases (pCi/Kg-wet)
(pCi/L)
(pCi/Kg-wet)
(pCi/Kg-dry)
(pCi/m3)
Gross Beta 4.0 0.01 NIA NIA NIA NIA H-3 2,000 (2)
NIA NIA NIA NIA NIA Mn-54 15 NIA 130 NIA NIA NIA Fe-59 30 NIA 260 NIA NIA NIA Co-58, Co-60 15 NIA 130 NIA NIA NIA Zn-65 30 NIA 260 NIA NIA NIA Zr-95 30 NIA NIA NIA NIA NIA Nb-95 15 NIA 1-131 1 (3) 0.07 NIA 1
60 NIA Cs-134 15 0.05 130 15 60 150 Cs-137 18 0.06 150 18 80 180 Ba-La-140 15 15 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 3,000 pCi/L may be used.
3 LLD for drinking water samples. If no drinking water pathway exists, the LLD of gamma isotopic may be used.
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 18 of 60 Company: Enterav Operations, Inc.
I Plant: Grand Gulf Nuclear Station 8.0 SAMPLING PROGRAM, PROGRAM MODIFICATION AND INTEPRETATION OF RESULTS 8.1 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 result of above ground nuclear weapons testing. It is important to note, levels of Cs-137 in the 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.
Environmental Direct Radiation Dosimetry Results Grand Gulf Nuclear Station reports measured dose as net exposure (field reading less transit reading) normalized to 92 days and relied on comparison of the indicator locations to the control as a measure of plant impact. Grand Gulf Nuclear Station's comparison of the inner ring and special interest area TLD results to the control, as seen in Table 8, identified no noticeable trend that would indicate that the ambient radiation levels are being affected by plant operations. In addition, the inner ring value of 10.1 millirem/quarter (mR/Qtr) shown in Table 8 for 2024 is within the historical bounds of 2014 -2023 annual average results, which have ranged from 9.3 to 10.0 mrem. Overall, Grand Gulf Nuclear Station concluded that the ambient radiation levels are not being affected by plant operations.
Table 8: Direct Radiation Annual Results Year Inner Ring (mR/Qtr)
Outer Ring (mR/Qtr)
Control (mR/Qtr) 2014 10.0 9.9 11.0 2015 9.6 9.5 10.8 2016 9.3 9.3 10.7 2017 9.9 9.9 11.3 2018 9.7 9.8 10.6 2019 10.0 9.7 10.7 2020 9.6 9.4 10.7 2021 9.9 10.2 11.7 2022 9.6 9.7 10.8 2023 10.0 10.1 11.2 2024 10.1 10.1 10.9
Annual Radiological Environmental Operating Report I YEAR: 2024 I
Page 19 of 60 Company: Enterav Operations, Inc.
I Plant: Grand Gulf Nuclear Station GGNS is in the process of converting to ANSI/HPS N13.37-2014. Dose is measured as net exposure (field reading less transit reading) normalized to 91-day quarters.
Data will be 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 (MOD), 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. MOD 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.
During the calendar year 2024, a total of 116 locations were monitored and data analyzed in accordance with the requirements in Table 1, Attachment 4, Environmental Direct Radiation Dosimetry Results, provides the annual direct radiation dosimetry analysis.
There was no direct radiation dose detected from the facility. All TLD measurements were analyzed, and none were found to have radiation levels that had increased over normal background radiation levels. TLD results are in Table 14, Table 15 and Table
- 16.
Annual Radiological Environmental Operating Report I YEAR: 2024 I
Page 20 of 60 Company: Enterav Operations, Inc.
I Plant: Grand Gulf Nuclear Station 8.2 Air Particulate and Radioiodine Sample Results Air particulate filters and charcoal canisters were collected from locations specified in Table 1,. During the calendar year 2024, a total of 422 of 424 scheduled samples were collected and analyzed for gross beta, gamma emitters and iodine. Two samples were not collected due to equipment failure see Table 10: Sample Deviation Summary. 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 (1-131) analysis is performed weekly on radioiodine sample cartridges. All collected radioiodine samples were below detection limits.
In the absence of plant-related gamma radionuclides, gross beta activity is attributed to naturally occurring radionuclides. Attachment 1, Data Table Summary, which includes gross beta concentrations and provides a comparison of the indicator and control means and ranges emphasizes the consistent trends seen in this pathway to support the presence of naturally occurring activity. Therefore, it can be concluded that the airborne pathway continues to be unaffected by Grand Gulf Nuclear Station operations.
0.025 1: 0.020
u
- a. 0.015 0.010 0.005 0.000 2014 Air Particulate: Gross Beta 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024
~
Indicator
~
Control
- Pre-Operational Average Figure 4, 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 preoperational data as shown in Figure 4, there were no significant changes. Gross beta, iodine and gamma results are in Table 11, Table 12 and Table
- 13.
Annual Radiological Environmental Operating Report I YEAR: 2024 I
Page 21 of 60 Company: Enterav Operations, Inc.
I Plant: Grand Gulf Nuclear Station 8.3 Waterborne Sample Results 8.3.1 Surface Water (i.e., Bay, Lake etc.)
Surface water samples are collected from two indicator locations (Outfall 007&
MRDOWN) and one control location (MRUP) and analyzed for gamma emitting radionuclides and tritium. During the calendar year 2024, a total of ~4 surface water samples were collected and analyzed in accordance with the requirements in the ODCM and shown in Table 3, Exposure Pathway - Waterborne. Plant related gamma emitting radionuclides and tritium remained undetectable in the upstream and downstream Mississippi River locations, Figure 5, Surface Water Tritium Results, which is consistent with previous operational years. Storm waters contribute to Outfall 007 and can include tritium due to washout and entrainment of normal, previously monitored gaseous effluents. As a result, tritium is occasionally observed.
Tritium was measured January (1,720 pCi/L), February (951 pCi/L) and June (755 pCi/L) at the Outfall 007 location. Tritium was not observed in the remaining Outfall 007 samples collected during 2024. Tritium concentrations in surface water were well below the reporting levels of Table 6, Reporting Levels for Radioactivity Concentrations in Environmental Samples, 30,000 pCi/L. Surface water sample results are in Table 18, Table 19 and Table 25.
Mississippi River Surface Water 3000 2500 2000
...J 0 1500
- 0.
1000 500 0
2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024
- 6.
Indicator MDC 0
Control MDC Pre-Operational Average Figure 5, Surface Water Tritium Results
Annual Radiological Environmental Operating Report I YEAR: 2024 I
Page 22 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station 8.3.2 REMP Groundwater Groundwater monitoring data collected during administration of the Groundwater Protection initiative (GPI) site program are included in the Annual Radioactive Effluent Release Report.
8.3.3 Drinking Water A total of 4 drinking water samples were obtained in 2024. These samples were analyzed for 1-131, gamma radionuclides and tritium in accordance with requirements in the ODCM and shown in Table 3, Exposure Pathway-Waterborne. During 2024, gamma radionuclides, 1-131, and tritium concentrations were below the LLD limits at the indicator and control locations, which is consistent with previous operational years. Results are reported as annual average pCi/L.
Analysis lodine-131 Gamma Tritium 2024
<LLD
<LLD
<LLD 2014-2023 Properational
<LLD
<LLD
<LLD
<LLD
<LLD
<LLD Grand Gulf Nuclear Station personnel have noted no definable trends associated with drinking water results at the indicator location. Therefore, the operation of Grand Gulf Nuclear Station had no definable impact on this waterborne pathway during 2024 and levels of radionuclides remain similar to those obtained in previous operational years.
Results from 2024 are summarized in Attachment 1 and details are in Table 20 and Table 21.
Annual Radiological Environmental Operating Report I YEAR: 2024 I
Page 23 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station 8.3.4 Sediment from Shoreline Shoreline sediment collections were made in two locations in 2024 and analyzed for gamma-emitting isotopes. Samples are collected at both indicator and control locations. A total of 4 shoreline samples were analyzed in accordance with requirements in the ODCM and shown in Table 3, Exposure Pathway - Waterborne.
Listed below is a comparison of 2024 indicator results to the 2014 - 2023 operational years. Grand Gulf Nuclear Station operations had no significant impact on the environment or public by the waterborne pathway. Results are reported as pCi/g.
Results from 2024 are summarized in Attachment 1 and details are in Table 22.
Monitoring Period 2014 - 2023 (Minimum Value) 2024 Value 2014-2023 (Maximum Value)
Preoperational 8.4 Ingestion Pathway Sample Results 8.4.1 Milk Result
<LLD
<LLD
<LLD 295.0 No milk samples are present within 8 km, broadleaf samples are collected from broad leaf vegetation grown in one of two different offsite locations of highest anticipated annual average ground level atmospheric deposition factors (D/Q).
8.4.2 Fish and Invertebrates A total of 4 fish and invertebrate samples were collected in 2024. These samples were analyzed for gamma emitting radionuclides, in accordance with requirements of the ODCM and summarized in Table 4, Exposure Pathway-Ingestion. These samples are collected from the indicator and control areas as required by the ODCM.
In 2024, gamma radionuclides were below detectable limits which are consistent with preoperational and operational years. Therefore, based on these measurements, Grand Gulf Nuclear Station operations had no significant radiological impact upon the environment or public by this ingestion pathway. environment or public by the waterborne pathway. Results are reported as pCi/g. Results from 2024 are summarized in Attachment 1 and details are in Table 23.
Annual Radiological Environmental Operating Report I YEAR: 2024 I
Page 24 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station 8.4.3 Food Products In accordance with the ODCM and as described in Table 4, Exposure Pathway -
Ingestion, 14 samples were collected from growing locations nearest site boundary in areas of highest predicted annual average ground level D/Q. Samples are collected and analyzed for gamma isotopic and I 131 from the indicator and control locations quarterly. It is common to detect Cs-137 in broadleaf samples at both indicator and control locations. Cs-137 can be attributed to offsite sources such as weapons testing, Chernobyl, and Fukushima events.
In 2024, food product samples were collected from two locations and analyzed for plant related lodine-131 and gamma radionuclides. The 2024 levels remained undetectable, as has been the case in previous years. Therefore, based on these measurements, Grand Gulf Nuclear Station operations had no significant radiological impact upon the environment or public by this ingestion pathway. Results from 2024 are summarized in Attachment 1 and details are in Table 24.
8.4.4 Special Sample A total of 1 deer meat sample was analyzed in 2024, for gamma emitting radionuclides. The 2024 levels remained undetectable, as has been the case in previous years. Therefore, based on these measurements, Grand Gulf Nuclear Station operations had no significant radiological impact upon the environment or public by this ingestion pathway. Results from 2024 are summarized in Attachment 1 and details are in Table 26.
9.0 LAND USE CENSUS A land use census is performed every two years as 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.
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 9: Land Use Census - Nearest Receptors within 5 miles. In summary, the highest D/Q locations for nearest garden, nearest residence and nearest milk animal did not change following the 2024 census.
The land use census identified no milk-producing animals within a five-mile radius of the plant site. In accordance with ODCM Section 6.12.1, Grand Gulf Nuclear Station personnel sampled broadleaf vegetation.
Annual Radiological Environmental Operating Report I YEAR: 2024 I
Page 25 of 60 Company: Enterav Operations, Inc.
I Plant: Grand Gulf Nuclear Station Table 9: Land Use Census - Nearest Receptors within 5 miles Sector Direction Nearest Residence Nearest Milk Animal Nearest Garden (Miles)
(Miles)
(Miles)
A N
1.02 none within 5 miles none within 5 miles B
NNE 1.51 none within 5 miles 1.52 C
NE 0.70 none within 5 miles none within 5 miles D
ENE 2.60 none within 5 miles 4.50 E
E 0.83 none within 5 miles 0.91 F
ESE 2.25 none within 5 miles none within 5 miles G
SE 3.72 none within 5 miles 4.20 H
SSE 1.10 none within 5 miles 4.31 J
s 3.14 none within 5 miles none within 5 miles K
SSW 2.20 none within 5 miles 2.18 L
SW 0.89 none within 5 miles 0.89 M
WSW none within 5 miles none within 5 miles none within 5 miles N
w none within 5 miles none within 5 miles none within 5 miles p
WNW none within 5 miles none within 5 miles none within 5 miles Q
NW none within 5 miles none within 5 miles none within 5 miles R
NNW 1.44 none within 5 miles none within 5 miles 10.0 SAMPLE DEVIATIONS, ANOMALIES AND UNAVAILABILITY Sampling and analysis are performed for media types addressed in the Offsite Dose Calculation Manual. Sampling and analysis challenges may be experienced due to a multitude of reasons including environmental factors, loss of TLDs, 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 I YEAR: 2024 I Page 26 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station Table 10: Sample Deviation Summary Sample Location Collection Reason for not conducting Plans for preventing Type and Date or REMP sampling as required reoccurrence Analysis Period by ODCM Air-Gross AS-1 05/28/24-Sample Deviation Replaced faulty equipment. CR-Beta 06/04/24 Equipment malfunction GGN-2024-03532 Air-Iodine AS-1 05/28/24 -
Sample Deviation Replaced faulty equipment. CR-06/04/24 Equipment malfunction GG N-2024-03532 11.0 11.1 11.2 11.3 11.4 OTHER SUPPLEMENTAL INFORMATION NEI 07-07 Onsite Radiological Groundwater Monitoring Program Grand Gulf Nuclear Station 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.
Independent Spent Fuel Storage Installation (ISFSI) Monitoring Program The ISFSI annual report on radioactive releases is submitted as a separate report.
lnterlaboratory Comparison Results Teledyne Brown Engineering and Stanford Dosimetry analyzed interlaboratory comparison samples to fulfill the requirements of ODCM Specification 6.12.1. Results are shown in Attachment 3.
Corrections to Previous Reports There are no corrections to previous AREOR reports identified.
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 27 of 60 Company: Enterav Operations, Inc.
I Plant: Grand Gulf Nuclear Station 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.
[1 O] "NUREG/CR-2919, "XOQDOQ Computer Program for the Meteorological Evaluation of Routine Effluent Releases at Nuclear Power Stations,"," Nuclear Regulatory Commission, September, 1982.
[11] "Measurements of Radionuclides in the environment Sampling and Analysis of plutonium in soil,"
Nuclear Regulatory Commission, 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 Initiative-Final Guidance Document,"," Nuclear Energy Institute, Washington, D.C..
Annual Radiological Environmental Operating Report I YEAR: 2024 I
Page 28 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station
[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..
l
[22] Nuclear Regulatory Commission, 25 June 2015. [Online]. Available: http://www.nrc.gov/reading-rm/basic-ref/students/animated-bwr.html. [Accessed October 2020].
[23] "NEI 07-07, "Industry Ground Water Protection Initiative-Final Guidance Document," Rev. 1,"
Nuclear Energy Institute, Washington, D.C., 2019.
[24] Nuclear Regulatory Commission, 25 June 2015. [Online]. Available: http://www.nrc.gov/reading-rm/basic-ref/students/animated-bwr.html. [Accessed October 2020].
[25] [Online]. Available: http://hps.org/hpspublications/radiationfactsheets.html. [Accessed 2020].
[26] "Japan Atomic Energy Agency," 06 November 2020. [Online]. Available:
https:/ /www.jaea.go.jp/eng I ish/04/ntokai/houkan/hou kan _ 02. html.
[27] "NRC Resource Page," [Online]. Available: http://www.nrc.gov/about-nrc/radiation.html. [Accessed 10 November 2020].
[28] "NUREG-0133, Preparation of Effluent Technical Specifications for Nuclear Power Plants,"
Nuclear Regulatory Commission, 1987.
[29] Nuclear Regulatory Commission, 30 June 2015. [Online]. Available: http://www.nrc.gov/reading-rm/basic-ref/students/animated-pwr.html. [Accessed October 2020].
[30] "Regulatory Guide 4.13, Performance, Testing, and Procedural Specifications for Thermoluminescence Dosimetry: Environmental Applications, Revision 2," Nuclear Regulatory Commision, June, 2019.
[31] "Regulatory Guide 4.15, Quality Assurance for Radiological Monitoring Programs (Inception through Normal Operations to License Termination) -- Effluent Streams and the Environment,"
Nuclear Regulatory Commission, July, 2007.
[32] "10 CFR 50 - Domestic Licensing of Production and Utilization Facilities," US Nuclear Regulatory Commission, Washington, DC.
[33] "40 CFR 190 - Environmental Radiation Protection Standards for Nuclear Power Operation," US Environmental Protection Agency, Washington, DC.
[34] "NUREG-0324 - XOQDOQ, Program for the Meteorological Evaluation of Routine Effluent Releases at Nuclear Power Stations," Nuclear Regulatory Commission, September, 1977.
[35] "NCRP Report No. 160 - Ionizing Radiation Exposure of the Population of the United States,"
National Council on Radiation Protection and Measurements, Bethesda, MD, 2009.
[36] "Regulatory Guide 1.109 - Calculation of Annual Doses to Man from Routine Releases of Reactor Effluents for the Purpose of Demonstrating Compliance with 1 O CFR Part 50, Appendix I," Nuclear Regulatory Commission, Ocotober, 1977.
[37] "40 CFR 141 - National Primary Drinking Water Regulations," US Environmental Protection Agency, Washington, DC..
[38] "10 CFR 20 - Standards for Protection Against Radiation," US Nuclear Regulatory Commission, Washington, DC.
[39] "4th Quarter 2024 Quality Assurance Report, Teledyne Brown Engineering Environmental Services, 2024".
[40] "Annual Quality Assurance Status Report," Environmental Dosimetry Company, 2024.
Annual Radiological Environmental Operating Report I YEAR: 2024 l___f_age 29 of 60 Company: Entergy QQerations, Inc.
I Plant: Grand Gulf Nuclear Station, Data Table Summary Location with the Highest Annual Control Sample Type Type/ Number Indicator Locations Mean Locations Number of (Units) of Analyses LLD [Note2]
Mean (F)INote 31 Mean (F)[Note 3]
Non-Routine
[Note 1]
[Range]
Mean (F)[Note 3]
Results [Note 51 Location [Note 41
[Range]
[Range]
GB/ 211 0.01 0.0224 (158 / 158)
AS-20 GR 0.0226 (53 I 53) 0.0225 (53 I 53) 0 Air
[0.0064 - 0.0435]
(Sector L, 0.9 mi)
[0.0083 - 0.0393]
[0.0077 - 0.0395]
Particulates GS I 16 (pCi/m 3)
Cs-134 0.05
<LLD N/A N/A
<LLD 0
CS-137 0.06
<LLD N/A N/A
<LLD 0
Airborne 1-131 / 211 0.07
< LLD N/A N/A
< LLD 0
Iodine (pCi/ m3)
Inner Ring Gamma I 56
[Note 6]
10.1 (56 / 56)
M-99 12.4 (4 I 4)
TLDs (mR/Qtr)
N/A 0
[6.6 -14.0]
(Sector K, 0.4 mi.)
[11.1 -14.0]
Outer Ring Gamma /28
[Note 6]
10.1 (28 / 28)
M-57 11.8(4/4)
N/A 0
TLDs (mR/Qtr)
[5.2 - 12.7]
(Sector F, 4.5 mi.)
[10.1 -12.7]
Special Interest TLDs Gamma I 28 (Note6]
10.4 (28 / 28)
M-01 11.7 (4 I 4)
N/A 0
(mR/Qtr)
[8.3 -12.9]
(Sector E, 3.5 mi.)
[10.6 - 12.5]
Control TLD Gamma I 4
[Note 6]
N/A N/A NIA 10.9 (4 / 4) 0 (mR/Qtr)
[9.3 - 11.8]
Annual Radiological Environmental Operating Report
/ YEAR: 2024 I Page 30 of 60 Com~: Entergy Operations, Inc.
l Plant: Grand Gulf Nuclear Station, Data Table Summary Location with the Highest Annual Control Sample Type Type/ Number Indicator Locations Mean Locations Number of of Analyses LLD [Note2]
Mean (F)[Note 3]
Non-Routine (Units)
[Note 1)
[Range)
Mean (F)[Note 3J Mean (F)[Note 3)
Results [Note SJ Location [Note 41
[Range)
[Range]
H-3 / 44 3000 1180 (5 / 36)
Outfall 007 831 (5 / 26)
< LLD 0
[755 -1720]
(Sector N, 0.2 mi.)
[755 -1720]
GS I 18 Mn-54 15
< LLD N/A N/A
< LLD 0
Fe-59 30
< LLD N/A N/A
< LLD 0
Co-58 15
< LLD N/A N/A
< LLD 0
Surface Water Co-60 15
< LLD N/A N/A
< LLD 0
(pCi/1)
Zn-65 30
< LLD N/A N/A
< LLD 0
Zr-95 30
< LLD N/A N/A
< LLD 0
Nb-95 15
< LLD N/A N/A
< LLD 0
1-131 15
< LLD N/A N/A
< LLD 0
Cs-134 15
< LLD 0
Cs-137 18
< LLD N/A N/A
< LLD 0
Ba-140 60
< LLD N/A N/A
< LLD 0
La-140 15
< LLD N/A N/A
< LLD 0
Annual Radiological Environment_al Ope_!'ating Report J YEAR: 2024 [
Page 31 of 60 Company: Entergy Operations, Inc.
[ Plant: Grand Gulf Nuclear Station, Data Table Summary Location with the Highest Annual Control Sample Type Type/ Number Indicator Locations Mean Locations Number of (Units) of Analyses LLD [Note2]
Mean (F)[Note 3]
Mean (F)[Note 3]
Non-Routine
[Note 1]
[Range]
Mean (F)[Note 3]
Results [Note S]
Location [Note 41
[Range]
[Range]
1-131 / 4 1
< LLD N/A N/A
< LLD 0
H-3 / 4 2000
< LLD I
N/A N/A
< LLD 0
GS/ 4 Mn-54 15
< LLD N/A N/A
< LLD 0
Fe-59 30
< LLD N/A N/A
< LLD 0
Drinking Water Co-58 15
< LLD N/A N/A
< LLD 0
(pCi/1)
Co-60 15
< LLD N/A N/A
< LLD 0
Zn-65 30
< LLD N/A N/A
< LLD 0
Zr-95 30
< LLD N/A N/A
< LLD 0
Nb-95 15
< LLD N/A N/A
< LLD 0
Cs-134 15
< LLD N/A N/A
< LLQ 0
Cs-137 18
< LLD N/A N/A
< LLD 0
Ba-140 60
< LLD N/A N/A
< LLD 0
La-140 15
< LLD N/A N/A
< LLD 0
Sediment GS / 4
< LLD N/A N/A N/A 0
Cs-134 150 (pCi/kg)
Cs-137 180
< LLD N/A N/A N/A 0
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 32 of 60 Company: Entergy Operations, Inc.
J Plant: Grand Gulf Nuclear Station, Data Table Summary Location with the Highest Annual Control Sample Type Type/ Number Indicator Locations Mean Locations Number of of Analyses LLD [Note2]
Mean (F)INote 31 Non-Routine (Units)
[Note 1]
[Range]
Mean (F)[Note 3]
Mean (F)INote 3]
Results [Note SJ Location [Note 41
[Range]
[Range]
GS/4 Mn-54 130
< LLD N/A N/A
< LLD 0
Fe-59 260
< LLD N/A N/A
< LLD 0
Fish (pCi/kg)
Co-58 130
< LLD N/A N/A
< LLD 0
Co-60 130
< LLD N/A N/A
< LLD 0
Zn-65 260
< LLD N/A N/A
< LLD 0
Cs-134 130
< LLD N/A N/A
< LLD 0
Cs-137 150
< LLD N/A N/A
< LLD 0
1-131 / 14 60
< LLD N/A N/A N/A 0
Food Products GS/ 14 (pCi/kg)
Cs-134 60
Cs-137 80
< LLD N/A N/A N/A 0
Annual Radiological Environmental Operating Report TvEAR: io24 l Page 33 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Data Table Summary Location with the Highest Annual Sample Type Type/ Number Indicator Locations Mean of Analyses LLD [Note2]
Mean (F)[Note 3]
(Units)
[Note 1]
[Range]
Mean (F)[Note 3]
Location [Note 41
[Range]
GS I 10 Mn-54 15
< LLD N/A N/A Fe-59 30
< LLD N/A N/A Co-58 15
< LLD N/A N/A Surface Water Zn-65 30
< LLD N/A N/A (Special)
Zr-95 30
< LLD N/A N/A Nb-95 15
< LLD N/A N/A (pCi/1) 1-131 15
< LLD N/A N/A Cs-134 15
< LLD N/A N/A Ba-140 60
< LLD N/A N/A La-140 15
< LLD N/A N/A GS I 1 Mn-54 130
< LLD N/A N/A Meat Fe-59 260
< LLD N/A N/A (Special)
Co-58 130
< LLD N/A N/A (pCi/kg)
Zn-65 260
< LLD N/A N/A Cs-134 130
< LLD N/A N/A LEGEND:
[Note 1]- GB= Gross beta; 1-131 = lodine-131 ; H-3 = Tritium; GS= Gamma scan.
[Note 2] - LLD= Required lower limit of detection based on ODCM Table 6.12.1-3.
Control Locations Mean (F)[Note 3]
[Range]
< LLD
< LLD
< LLD
< LLD
< LLD
< LLD
< LLD
< LLD
< LLD
< LLD
< LLD
< LLD
< LLD
< LLD
< LLD
< LLD
< LLD
< LLD
< LLD Number of Non-Routine Results [Note 51 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
Annual Radiological E:nvironment~I Operating Report I YEAR: 2024 I Page 34 of 60 Company: Enter-gy_ O~erations, Inc.
_J Plant: Grand Gulf Nuclear Station
[Note 3] - Mean and range based upon detectable measurements only. Fraction of detectable measurements at specified locations is indicated in parenthesis (F).
[Note 4] - Where applicable, locations are specified (1) by name, (2) distance from reactor site, and (3) meteorological sector.
[Note 5] - Non-routine results are those which exceed ten times the control station value. If no control station value is available, the result is considered non-routine if it exceeds ten times the preoperational value for the location.
[Note 6] - LLD is not defined in ODCM Table 6.12.1-3.
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 35 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024
Annual Radiological Environmental Operating Report I YEAR: 2024 I
Page 36 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 11, Air Particulate Data Summary Table Analysis: Gross Beta I
Units: pCi/m3 Station Station Station Station Start Date End Date AS-1 AS-7 AS-20 [Note 1]
AS-3 (Indicator)
(Indicator)
(Indicator)
(Control)
REQUIRED LLD ~
0.01 0.01 0.01 0.01 12/26/23 01/02/24 0.0364 0.0327 0.0278 0.0310 01/02/24 01/09/24 0.0250 0.0282 0.0234 0.0294 01/09/24 01/17/24 0.0308 0.0294 0.0346 0.0302 01/17/24 01/23/24 0.0210 0.0225 0.0189 0.0238 01/23/24 01/30/24 0.0064 0.0066 0.0083 0.0077 01/30/24 02/06/24 0.0229 0.0245 0.0245 0.0231 02/06/24 02/13/24 0.0154 0.0149 0.0164 0.0161 02/13/24 02/20/24 0.0262 0.0251 0.0219 0.0252 02/20/24 02/27/24 0.0210 0.0252 0.0273 0.0226 02/27/24 03/05/24 0.0148 0.0150
, 0.0161 0.0151 03/05/24 03/12/24 0.0143 0.0154 0.0130 0.0153 03/12/24 03/19/24 0.0205 0.0217 0.0215 0.0178 03/19/24 03/26/24 0.0208 0.0186 0.0218 0.0176 03/26/24 04/02/24 0.0250 0.0209 0.0217 0.0204 04/02/24 04/09/24 0.0181 0.0189 0.0187 0.0216 04/09/24 04/16/24 0.0149 0.0139 0.0144 0.0132 04/16/24 04/23/24 0.0185 0.0185 0.0195 0.0189 04/23/24 04/30/24 0.0219 0.0208 0.0217 0.0217 04/30/24 05/07/24 0.0172 0.0138 0.0173 0.0166 05/07/24 05/14!24 0.0149 0.0160 0.0194 0.0143 05/14/24 05/21/24 0.0188 0.0194 0.0203 0.0213 05/21/24 05/28/24 0.0258 0.0225 0.0269 0.0226 05/28/24 06/04/24 See Table 10 0.0187 0.0164 0.0155 06/04/24 06/11/24 0.0216 0.0190 0.0195 0.0147 06/11/24 06/18/24 0.0191 0.0180 0.0209 0.0182 06/18/24 06/25/24 0.0150 0.0135 0.0168 0.0173 06/25/24 07/02/24 0.0127 0.0136 0.0127 0.0111
Annual Radiological Environmental Operating Report I YEAR: 2024 I
Page 37 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 11, Air Particulate Data Summary Table Analysis: Gross Beta I
Units: pCi/m3 Station Station Station Station Start Date End Date AS-1 AS-7 AS-20 [Note 1)
AS-3 (Indicator)
(Indicator)
(Indicator)
(Control)
REQUIRED LLD +
0.01 0.01 0.01 0.01 07/02/24 07/09/24 0.0213 0.0221 0.0224 0.0242 07/09/24 07/16/24 0.0216 0.0244 0.0237 0.0214 07/16/24 07/23/24 0.0170 0.0147 0.0199 0.0188 07/23/24 07/30/24 0.0129 0.0119 0.0128 0.0141 07/30/24 08/06/24 0.0323 0.0287 0.0242 0.0293 08/06/24 08/13/24 0.0332 0.0293 0.0356 0.0320 08/13/24 08/20/24 0.0295 0.0280 0.0272 0.0318 08/20/24 08/27/24 0.0274 0.0277 0.0300 0.0271 08/27/24 09/03/24 0.0151 0.0158 0.0166 0.0188 09/03/24 09/10/24 0.0230 0.0263 0.0268 0.0274 09/10/24 09/17/24 0.0180 0.0219 0.0175 0.0235 09/17/24 09/24/24 0.0274 0.0281 0.0297 0.0284 09/24/24 10/01/24 0.0283 0.0275 0.0296 0.0320 10/01/24 10/08/24 0.0322 0.0322 0.0331 0.0288 10/08/24 10/15/24 0.0198 0.0195 0.0212 0.0199 10/15/24 10/22/24 0.0288 0.0283 0.0229 0.0213 10/22/24 10/29/24 0.0376 0.0356 0.0373 0.0395 10/29/24 11/05/24 -
0.0160 0.018 0.0187 0.0184 11/05/24 11/12/24 0.0139 0.0132 0.0166 0.0140 11/12/24 11 /19/24 0.0287 0.0287 0.0278 0.0299 11/19/24 11/26/24 0.0236 0.0257 0.0258 0.0214 11/26/24 12/03/24 0.0435 0.0410 0.0393 0.0369 12/03/24 12/10/24 0.0308 0.0260 0.0306 0.0334 12/10/24 12/17/24 0.0185 0.0176 0.0180 0.0213 12/17/24 12/23/24 0.0239 0.0287 0.0260 0.0262 12/23/24 12/31/24 0.0253 0.0249 0.0233 0.0284
[Note 1] - Station with highest annual mean.
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 38 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 12, Radioiodine Cartridge Data Table Summary Analysis: 1-131 I
Units: pCi/m3 Start Date End Date AS-1 AS-7 AS-20 AS-3 (Indicator)
(Indicator)
(Indicator)
(Control)
REQUIRED LLD -+
0.07 0.07 0.07 0.07 12/26/23 01/02/24
<0.0472
<0.0482
<0.0482
<0.0489 01/02/24 01/09/24
<0.0419
<0.0171
<0.0410
<0.0424 01/09/24 01/17/24
<0.0483
<0.0473
<0.0478
<0.0479 01/17/24 01/23/24
<0.0539
<0.0528
<0.0536
<0.0538 01/23/24 01/30/24
<0.0393
<0.0386
<0.0398
<0.0395 01/30/24 02/06/24
<0.0287
<0.0134
<0.0282
<0.0292 02/06/24 02/13/24
<0.0330
<0.0328
<0.0327
<0.0328 02/13/24 02/20/24
<0.0322
<0.0318
<0.0316
<0.0322 02/20/24 02/27/24
<0.0449
<0.0446
<0.0444
<0.0446 02/27/24 03/05/24
<0.0440
<0.0434
<0.0433
<0.0438 03/05/24 03/12/24
<0.0466
<0.0463
<0.0462
<0.0464 03/12/24 03/19/24
<0.0503
<0.0497
<0.0502
<0.0507 03/19/24 03/26/24
<0.0307
<0 0230
<0.0303
<0.0311 03/26/24 04/02/24
<0.0445
<0.0436
<0.0438
<0.0422 04/02/24 04/09/24
<0.0489
<0.0482
<0.0485
<0.0496 04/09/24 04/16/24
<0.0349
<0.0344
<0.0345
<0.0346 04/16/24 04/23/24
<0.0307
<0.0307
<0.0233
<0.0308 04/23/24 04/30/24
<0.0321
<0.0344
<0.0326
<0.0327 04/30/24 05/07/24
<0.0287
<0.0684
<0.0682
<0.0691 05/07/24 05/14/24
<0.0427
<0.0441
<0.0474
<0.0447 05/14/24 05/21/24
<0.0305
<0.0306
<0.0306
<0.0311 05/21/24 05/28/24
<0.0547
<0.0551
<0.0228
<0.0562 05/28/24 06/04/24 See Table 10
<0.0269
<0.0272
<0.0110 06/04/24 06/11/24
<0.0561
<0.0508
<0.0510
<0.0518 06/11/24 06/18/24
<0.0410
<0.0354.
<0.0363
<0.0362 06/18/24 06/25/24
<0.0629
<0.0616
<0.0632
<0.0623 06/25/24 07/02/24
<0.0476
<0.0464
<0.0479
<0.0467
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 39 of 60 Company: Enterav Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 12, Radioiodine Cartridge Data Table Summary Analysis: 1-131 I
Units: pCi/m3 Start Date End Date AS-1 AS-7 AS-20 AS-3 (Indicator)
(Indicator)
(Indicator)
(Control)
REQUIRED LLD -+
0.07 0.07 0.07 0.07 07/02/24 07/09/24
<0.0300
<0.0289
<0.0301
<0.0298 07/09/24 07/16/24
<0.0300
<0.0294
<0.0301
<0.0299 07/16/24 07/23/24
<0.0318
<0.0316
<0.0318
<0.0319 07/23/24 07/30/24
<0.0326
<0.0247
<0.0325
<0.0325 07/30/24 08/06/24
<0.0536
<0.0522
<0.0537
<0.0537 08/06/24 08/13/24
<0.0406
<0.0393
<0.0404
<0.0408 08/13/24 08/20/24
<0.0338
<0.0325
<0.0332
<0.0357 08/20/24 08/27/24
<0.0361
<0.0349
<0.0356
<0.0349 08/27/24 09/03/24
<0.0320
<0.0314
<0.0314
<0.0318 09/03/24 09/10/24
<0.0302
<0.0291
<0.0225
<0.0298 09/10/24 09/17/24
<0.0149
<0.0367
<0.0148
<0.0148 09/17/24 09/24/24
<0.0435
<0.0436
<0.0434
<0.0434 09/24/24 10/01 /24
<0.0206
<0.0206
<0.0156
<0.0207 10/01/24 10/08/24
<0.0367
<0.0366
<0.0363
<0.0360 10/08/24 10/15/24
<0.0247
<0.0247
<0.0246
<0.0244 10/15/24 10/22/24
<0.0419
<0.0423
<0.0417
<0.0430 10/22/24 10/29/24
<0.0446
<0.0442
<0.0440
<0.0446 10/29/24 11/05/24
<0.0304
<0.0311
<0.0313
<0.0233 11/05/24 11/12/24
<0.0318
<0.0316
<0.0241
<0.0319 11/12/24 11/19/24
<0.0532
<0.0529
<0.0533
<0.0536 11/19/24 11/26/24
<0.0462
<0.0349
<0.0467
<0.0469 11/26/24 12/03/24
<0.0312
<0.0307
<0.0314
<0.0313 12/03/24 12/10/24
<0.0381
<0.0376
<0.0382
<0.0380 12/10/24 12/17/24
<0.0344
<0.0345
<0.0347
<0.0345 12/17/24 12/23/24
<0.0621
<0.0628
<0.0633
<0.0621 12/23/24 12/31/24
<0.0336
<0.0430
<0.0432
<0.0335
Annual Radiological Environmental Operating Report l YEAR: 2024 l Page 40 of 60 Company: Enterav Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 1.0 T able 13, Air Gamma Quarterlv Comoosite Analysis: Gamma Isotopic Units: pCi/cu.m Location Date CS-134 CS-137 REQUIRED LLD ~
0.05 0.06 AS-1
<0.0032
< 0.0025 AS-3
<0.0021
< 0.0019 03/26/24 AS-7
<0.0020
< 0.0017 AS-20
<0.0016
< 0.0016 AS-1
<0.0025
< 0.0019 AS-3
<0.0013
< 0.0014 06/25/24 AS-7
<0.0017
< 0.0015 AS-20
<0.0026
< 0.0019 AS-1
<0.0023
< 0.0016 AS-3 09/24/24
<0.0013
< 0.0017 AS-7
<0.0034
< 0.0022 AS-20
<0.0024
< 0.0014 AS-1
<0.0020
< 0.0022 AS-3
<0.0014
<0.0014 12/31/24 AS-7
<0.0016
< 0.0013 AS-20
<0.0022
< 0.0013
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 41 of 60 Company: Enterav Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 14, Thermoluminescent Dosimeters - Inner Ring Analysis: Gamma Dose I
Units: mrem Station 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr Annual 2024 2024 2024 2024 Mean 2024 M-16 11.0 10.5 10.9 12.4 11.2 M-19 9.2 9.0 9.5 11.3 9.7 M-21 11.7 11.7 12.3 13.0 12.2 M-22 8.3 8.3 8.6 10.0 8.8 M-23 8.7 8.6 9.2 9.9 9.1 M-25 8.8 6.6 8.7 9.4 8.4 M-28 10.6 9.9 11.4 12.2 11.0 M-94 10.1 8.5 10.5 14.0 10.8 M-95 7.2 9.6 7.3 8.5 8.1 M-96 9.8 6.6 9.4 10.5 9.1 M-97 7.7 10.2 7.9 9.2 8.8 M-98 11.6 7.8 11.8 13.3 11.1 M-99[Note 1]
12.0 11.1 12.7 14.0 12.4 M-100 10.3 12.1 10.9 12.3 11.4
[Note 1] - Station with highest annual mean.
Annual Radiological Environmental Operating Report I YEAR: 2024 I
Page 42 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 15, Thermoluminescent Dosimeters - Outer Ring Analysis: Gamma Dose I
Units: mrem Station 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr Annual Mean 2024 2024 2024 2024 2024 M-36 8.2 11.9 8.5 9.6 9.6 M-40 5.9 8.2 5.6 7.2 6.7 M-48 10.0 5.2 10.2 11.1 9.1 M-49 11.1 9.5 11.3 12.4 11.1 M-50 10.4 10.8 10.8 11.1 10.8 M-55 12.7 10.1 12.0 12.0 11.7 M-57[Note 1]
11.7 11.2 11.7 12.5 11.8
[Note 1] - Station with highest annual mean.
Table 16, Thermoluminescent Dosimeters - Special Interest Areas Analysis: Gamma Dose I
Units: mrem Station 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr Annual Mean 2024 2024 2024 2024 2,024 M-01[Note1]
10.6 11.8 11.9 12.5 11.7 M-07 10.5 9.9 10.4 11.4 10.6 M-09 10.3 9.6 10.3 11.1 10.3 M-10 8.4 8.3 8.8 9.4 8.7 M-33 11.9 11.9 11.4 12.9 12.0 M-38 9.6 8.4 9.3 10.8 9.5 M-39 9.6 8.8 9.6 10.9 9.7
[Note 1] - Station with highest annual mean.
Table 17, Thermoluminescent Dosimeters - Control Analysis: Gamma Dose I
Units: mrem Station 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr Annual Mean 2024 2024 2024 2024 2024 M-14 10.7 9.3 11.8 11.8 10.9
Annual Radiologic~! En_vironmental Operating Report J
YEAR: 2024 J
Page 43 of 60 Company: Entergy Operations, Inc.~ _ J Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 18, Surface Water - Gamma Analysis: Gamma Isotopic Units: pCi/L Location Date Mn-54 Co-58 Fe-59 Co-60 Zn-65 Nb-95 Zr-95 1-131 Cs-134 Cs-137 Ba-140 La-140 REQUIRED LLD-+
15 15 30 15 30 15 30 15 15
~
60 15 MRDOWN 01/31/24
<5.347
<6.149
<11.05
<5.329
<10.60
<5.422
<9.037
<12.13
<6.241
<6.703
<28.90
<9.223 MRUP 01/31/24
<7.123
<6.920
<14.40
<5.249
<17.81
<8.090
<12.44
<12.87
<9.587
<8.045
<36.46
<9.008 MRDOWN GG 01/31/24
<5.742
<5.580
<13.09
<8.355
<7.771
<6.401
<9.655
<11.3
<4.305
<5.744
<15.80
<14.26 MRUP GG 01/31/24
<8.021
<6.943
<14.52
<7.030
<11.54
<7.92
<12.17
<11.22
<7.262
<8.264
<36.55
<10.53 MRDOWN 05/01/24
<6.104
<5.670
<11.49
<6.674
<11.09
<6.858
<10.16
<9.386
<6.226
<5.625
<28.63
<10.98 MRUP 05/01/24
<5.771
<7.015
<12.14
<5.426
<12.23
<7.265
<12.66
<12.18
<5.929
<6.202
<32.43
<13.74 MRDOWN GG 05/01/24
<7.653
<6.554
<13.38
<9.958
<12.14
<6.475
<9.722
<10.33
<7.654
<9.138
<36.02
<12.33 MRUP GG 05/01/24
<6.880
<6.445
<16.18
<6.832
<12.29
<5.631
<11.66
<13.61
<7.691
<6.946
<36.76
<13.86 MRDOWN 07/31/24
<3.429
<3.854
<10.21
<4.432
<7.368
<3.702
<6.842
<11.34
<4.515
<4.078
<25.30
<8.113 MRUP 07/31/24
<4.059
<4.133
<8.766
<3.767
<8.377
<4.562
<7.821
<11.00
<4.852
<4.836
<25.88
<7.652
Annual Radiological Environmental Operating Report
[ YEAR: 2024 [
Page 44 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 18, Surface Water - Gamma Analysis: Gamma Isotopic Units: pCi/L Location Date Mn-54 Co-58 Fe-59 Co-60 Zn-65 Nb-95 Zr-95 1-131 Cs-134 REQUIRED LLD -+
15 15 30 15 30 15 30 15 15 MRDOWN GG 07/31/24
<4.488
<4.048
<9.572
<4.574
<9.602
<4.358
<8.878
<12.05
<5.116 MRUP GG 07/31/24
<3.660
<4.497
<9.805
<4.160
<8.190
<4.775
<9.139
<12.17
<5.138 MRDOWN 10/17/24
<6.292
<8.026
<13.26
<8.096
<18.68
<8.407
<13.34
<13.72
<6.062 MRUP 10/17/24
<6.032
<8.142
<18.98
<7.889
<16.71
<9.492
<13.14
<14.27
<8.001 MRDOWN GG 10/17/24
<5.479
<5.893
<11.01
<9.178
<13.03
<5.801
<10.38
<12.11
<6.683 MRUP GG 10/17/24
<6.035
<6.297
<16.21
<8.068
<11.36
<7.502
<10.87
<10.36
<6.406 MRDOWN*
10/17/24
<5.260
<5.659
<10.31
<5.970
<10.99
<5.575
<10.99
<10.27
<5.877 MRDOWN GG*
10/17/24
<6.036
<6.748
<13.68
<8.515
<16.38
<8.176
<11.75
<12.94
<8.566 GG - indicates duplicate sample
- - indicates annual sample collected during liquid effluent discharge Cs-137 18
<5.020
<4.822
<7.283
<7.515
<6.681
<6.515
<4.420
<7.077 Ba-140 La-140 60 15
<31.56
<7.771
<31.35
<8.858
<37.64
<12.07
<35.57
<14.01
<30.25
<9.898
<28.87
<10.33
<25.06
<8.094
<40.27
<13.62
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 45 of 60 Company: Enterav Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 19, Surface Water - Tritium Analysis: H-3 Units: pCi/L Location Date H-3 REQUIRED LLD+
3000 OUTFALL 007 01/03/24 1720 OUTFALL 007 GG 01/03/24 1690 OUTFALL 007 01/17/24
<626 OUTFALL 007 GG 01/17/24
<613 MRDOWN 01/31/24
<598 MRUP 01/31/24
<601 MRDOWN GG 01/31/24
<599 MRUP GG 01/31/24
<602 OUTFALL 007 02/13/24 951 OUTFALL 007 GG 02/13/24 786 OUTFALL 007 03/12/24
<592 OUTFALL 007 GG 03/12/24
<588 OUTFALL 007 04/16/24
<606 OUTFALL 007 GG 04/16/24
<598 MRDOWN 05/01/24
<632 MRUP 05/01/24
<616 MRDOWN GG 05/01/24
<628 MRUP GG 05/01/24
<630 OUTFALL 007 05/14/24
<670 OUTFALL 007 GG 05/14/24
<677 OUTFALL 007 06/10/24
<626 OUTFALL 007 GG 06/10/24 755 OUTFALL 007 07/15/24
<556 OUTFALL 007 GG 07/15/24
<550
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 46 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 19, Surface Water - Tritium Analysis: H-3 Units: pCi/L Location Date H-3 MRDOWN 07/31/24
<570 MRUP 07/31/24
<569 MRDOWN GG 07/31/24
<576 MRUP GG 07/31/24
<572 OUTFALL 007 08/13/24
<554 OUTFALL 007 GG 08/13/24
<560 OUTFALL 007 09/09/24
<543 OUTFALL 007 GG 09/09/24
<541 OUTFALL 007 10/15/24
<503 OUTFALL 007 GG 10/15/24
<505 MRDOWN 10/17/24
<577 MRUP 10/17/24
<592 MRDOWN GG 10/17/24
<576 MRUP GG 10/17/24
<581 MRDOWN*
10/17/24
<573 MRDOWN GG*
10/17/24
<574 OUTFALL 007 11/11/24
<529 OUTFALL 007 GG 11/11/24
<524 OUTFALL 007 12/16/24
<369 OUTFALL 007 GG 12/16/24
<366 GG - indicates duplicate sample
- - indicates Annual Sample collected during liquid discharge
Annual Radiological Environmental Operating Report J
YEAR: 2024 J
Pc:1ge 47 of 60 Company: Entergy Operations! Inc.
J Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 20, Drinking Water-Gamma, 1-131 Analysis: Gamma Isotopic, 1-131 Units: pCi/L Location Date 1-131 Mn-54 Co-58 Fe-59 Co-60 Zn-65 Nb-95 Zr-95 Cs-134 REQUIRED LLD -+
1 15 15 30 15 30 15 30 15 CONSTWELL 11/06/24
<0.777
<6.610
<5.721
<14.08
<9.230
<16.29
<7.275
<10.92
<7.364 CONSTWELL GG 11/06/24
<0.677
<7.301
<6.270
<12.55
<9.260
<13.00
<5.821
<12.15
<9.241 PGWELL 11/06/24
<0.699
<9.792
<7.249
<15.92
<11.57
<18.87
<7.810
<13.92
<9.406 PGWELL GG 11/06/24
<0.937
<6.989
<5.964
<14.36
<9.222
<13.37
<9.304
<11.73
<6.593 GG - indicates duplicate sample Cs-137 18
<7.651
<8.706
<7.828
<8.311 Ba-140 La-140 60 15
<19.14
<7.453
<25.34
<7.033
<39.59
<10.72
<24.63
<10.72
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 48 of 60 Company: Enterav Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 21, Drinking Water - Tritium Analysis: H-3 Units: pCi/L Location Date H-3 REQUIRED LLD +
2000 CONSTWELL 11/06/24
<489 CONSTWELL GG 11/06/24
<495 PGWELL 11/06/24
<522 PGWELL GG 11/06/24
<514 GG - indicates duplicate sample Table 22, Sediment Analysis: Gamma Isotopic Units: pCi/kg Location Date Cs-134 Cs-137 REQUIRED LLD +
150 180 SEDHAM 09/03/24
<95.48
<84.99 SEDHAM GG 09/03/24
<117.9
<88.32 SEDCONT 09/03/24
<93.34
<71.98 SEDCONT GG 09/03/24
<93.75
<77.15 GG - indicates duplicate sample
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 49 of 60 Company: Enterav Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 23, Fish Analysis: Gamma Isotopic Units: pCi/kg Location Collection Mn-54 Co-58 Fe-59 Co-60 Zn-65 Cs-134 Date REQUIRED LLD -+
130 130 260 130 260 130 FISHDOWN 08/21/24
<75.55
<58.83
<147.9
<40.74
<168.2
<79.63 FISHDOWN GG 08/21/24
<54.75
<56.33
<88.91
<51.89
<131.9
<79.17 FISHUP 08/21/24
<74.50
<82.06
<136.9
<75.54
<161.9
<88.79 FISHUP GG 08/21/24
<57.44
<72.52
<164.8
<50.83
<142.2
<52.55 GG - indicates duplicate sample Table 24, Food Products Analysis: Gamma Isotopic, 1-131 Units: pCi/kg Location Collection Date 1-131 Cs-134 Cs-137 REQUIRED LLD -+
60 60 80 VEG-CONT 02/07/24
<28.49
<37.23
<23.03 VEG-J 02/07/24
<36.67
<26.53
<23.21 VEG-CONT GG 02/07/24
<36.40
<23.23
<26.80 VEG-J GG 02/07/24
<36.03
<24.75
<27.08 VEG-CONT 05/14/24
<25.70
<29.59
<24.39 VEG-J 05/14/24
<24.06
<30.33
<29.95 VEG-CONT 08/06/24
<36.95
<33.13
<21.87 VEG-J 08/06/24
<49.55
<32.92
<35.97 VEG-CONT GG 08/06/24
<36.07
<27.72
<30.70 VEG-J GG 08/06/24
<51.18
<33.41
<25.54 VEG-CONT 11/04/24
<20.32
<19.31
<18.25 VEG-CONT GG 11/04/24
<19.34
<17.05
<17.43 VEG-J 11/04/24
<19.66
<17.92
<17.23 Cs-137 150
<81.13
<65.48
<92.10
<60.83
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 50 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 24, Food Products Analysis: Gamma Isotopic, 1-131 Units: pCi/kg Location Collection Date 1-131 Cs-134 Cs-137 VEG-J GG 11/04/24
<23.31
<19.43
<20.86 GG - indicates duplicate sample
Annual Radiologic~~E:n_viron_111enta! Qperating Report __ J_ Yl::~R: 2024 j
Page 51 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 25, Special Samples, Surface Water - Gamma Isotopic Analysis: Gamma Isotopic Units: pCi/L Location Date Mn-54 Co-58 Fe-59 Co-60 Zn-65 Nb-95 Zr-95 1-131 Cs-134 Cs-137 Ba-140 La-140 REQUIRED LLD ~
15 15 30 15 30 15 30 15 15 18 60 15 OSN 007 01/03/24
<6.316
<4.693
<11.70
<7.199
<10.55
<5.262
<12.72
<7.059
<5.707
<6.007
<22.94
<8.701 OSN 007 GG 01/03/24
<6.295
<7.408
<11.77
<5.714
<14.78
<5.847
<11.44
<9.184
<5.915
<7.632
<30.73
<5.632 OSN 007 03/12/24
<7.599
<6.302
<16.56
<9.193
<13.48
<6.352
<13.66
<11.94
<8.619
<7.007
<27.66
<11.39 OSN 007 GG 03/12/24
<7.879
<6.898
<16.59
<9.144
<16.68
<8.789
<11.64
<13.06
<8.115
<7.691
<35.02
<11.5 OSN 007 06/20/24
<6.981
<5.307
<16.30
<8.961
<19.48
<6.813
<12.73
<11.21
<7.115
<6.439
<32.98
<10.05 OSN 007 GG 06/20/24
<7.589
<6.805
<14.22
<7.72
<18.53
<7.991
<12.96
<10.53
<7.873
<7.084
<33.14
<11.44 OSN 007 09/18/24
<8.941
<7.54
<16.17
<7.216
<16.34
<7.964
<10.96
<14.07
<8.157
<7.376
<41.46
<7.159 OSN 007 GG 09/18/24
<6.573
<6.485
<12.76
<8.673
<14.06
<6.617
<10.17
<11.21
<6.27
<6.467
<31.88
<9.166 OSN 007 12/16/24
<4.549
<4.696
<9.975
<4.48
<6.941
<5.047
<7.648
<7.366
<5.035
<4.417
<20.12
<7.933 OSN 007 GG 12/16/24
<3.471
<4.169
<8.747
<5.354
<5.487
<3.945
<6.661
<6.444
<3.682
<3.478
<18.58
<7.335 GG - indicates duplicate sample
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 52 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Complete Data Table for All Analysis Results Obtained In 2024 Table 26, Special Samples, Meat Analysis: Gamma Isotopic Units: pCi/kg Location I
Date Mn-54 Co-58 Fe-59 Co-60 Zn-65 Cs-134 Cs-137 REQUIRED LLD -+
130 130 260 130 260 130 150 DEER
\\ 10/16/24
<85.63
<82.98
<166.1
<91.83
<190.7
<90.31
<82.35
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 53 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Cross Check lntercomparison Program, Cross Check lntercomparison Program
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 54 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Cross Check lntercomparison Program Summary of Cross Check Program Participation in cross check intercomparison studies is mandatory for laboratories performing analyses of REMP samples satisfying the requirements in the Offsite Site Dose Calculation Manual.
lntercomparison studies provide a consistent and effective means to evaluate the accuracy and precision of analyses performed by a laboratory. Study results should fall within specified control limits and results that fall outside the control limits are investigated and corrected.
Teledyne Brown Engineering Environmental Services participated in the following proficiency testing studies provided by Environmental Resource Associates (ERA), and Eckert Ziegler Analytics in 2024. The Laboratory's intercomparison program results for 2024 are summarized below. The Environmental Dosimetry Quality Assurance Status Report for 2024 can be found on page 58.
Teledyne Brown Engineering Summary of Results The Teledyne Brown Engineering Environmental Services (TSE-ES) laboratory analyzed Performance Evaluation (PE) samples of air particulate (AP), milk, soil, vegetation, and water matrices that represent test and matrix combinations available for REMP programs. The PE samples supplied by Eckert & Ziegler (E&Z) Analytics Inc., Environmental Resource Associates (ERA), and Department of Energy (DOE) Mixed Analyte Performance Evaluation Program (MAPEP), were evaluated against the following pre-set acceptance criteria:
A. E&Z Analytics Evaluation Criteria Analytics' evaluation report provides a ratio of TB E's result and E&Z Analytics' known value.
Since flag values are not assigned by E&Z Analytics, TSE evaluates the reported ratios based on internal QC requirements based on the DOE MAPEP criteria.
- 1. A= Acceptable - reported result falls within ratio limits of 0.80-1.20
- 2. W = Acceptable with warning - reported result falls within 0.70-0.80 or 1.20-1.30
- 3.
N = Not Acceptable - reported result falls outside the ratio limits of< 0.70 and > 1.30 B. ERA Evaluation Criteria ERA's evaluation report provides an acceptance range for control and warning limits with associated flag values. ERA's acceptance limits are established per the US EPA, National Environmental Laboratory Accreditation Conference (NELAC), state-specific Performance Testing (PT) program requirements or ERA's SOP for the Generation of Performance Acceptance Limits, as applicable. The acceptance limits are either determined by a regression equation specific to each analyte or a fixed percentage limit promulgated under the appropriate regulatory document.
- 1. A = Acceptable - Reported value falls within the Acceptance Limits
- 2. N = Not Acceptable -. Reported value falls outside of the Acceptance Limits C. DOE Evaluation Criteria MAPEP's evaluation report provides an acceptance range with associated flag values. MAPEP defines three levels of performance:
- 1. Acceptable (flag = "A") - result within +/- 20% of the reference value
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 55 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Cross Check lntercomparison Program
- 2. Acceptable with Warning (flag = "W') - result falls in the+/- 20% to +/- 30% of the reference value
- 3. Not Acceptable (flag = "N") - bias is greater than 30% of the reference value Note: The Department of Energy (DOE) Mixed Analyte Performance Evaluation Program (MAPEP) samples are created to mimic conditions found at DOE sites which do not always resemble typical environmental samples obtained at commercial nuclear power facilities.
The Inter-Laboratory Comparison Program provides evidence of "in control" counting systems and methods, and that the laboratories are producing accurate and reliable data. 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:
A. 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.
B. 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.
C. 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-231 to better reflect client sample testing and acceptable results were achieved.
Acceptable results returned in a later sample study, supporting effectiveness of corrective action.
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 56 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Cross Check lntercomparison Program D. NCR 24-06: E&Z Analytics March E14092 air particulate study Co-60 evaluated as "Not Acceptable." TSE reported 168 pCi and the known value returned at 126 pCi. Additionally, March E 14093 soil Ce-141 evaluated as "Not Acceptable." TSE reported 0.106 pCi/g and the known value returned at 0.071 pCi/g. The root cause investigation was unable to determine any anomaly thus no proposed corrective action. No recurrence has occurred.
E. CAR 24-02 (CAR 23-31): MAPEP February 24-MaS50 soil study Fe-55 evaluated as "Not Acceptable." TSE reported 297 Sq/Kg and the known value returned at 650 Sq/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.
F. NCR 24-08: MAPEP February 24-MaS50 soil study Ni-63 evaluated as "Not Acceptable."
TSE reported 1070 Sq/Kg and the known value returned at 1530 Sq/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. TSE analytical procedure TSE-2013 was updated to include this change.
G. 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 TSE's 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.
H. NCR 24-10: MAPEP February 24-MaW50 water study Tc-99 evaluated as "Not Acceptable."
TBE reported 9.95 Sq/Land the known value returned 7.47 Sq/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.
I.
NCR 24-11: MAPEP February 24-RdV50 vegetation study Sr-90 evaluated as "Not Acceptable." TSE reported 0.276 Sq/sample and the known value returned 0.529 Sq/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.
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 57 of 60 Company: Enterav Operations, Inc.
I Plant: Grand Gulf Nuclear Station, Cross Check lntercomparison Program J.
NCR 24-14: ERA September MRAD-41 air particulate study U-234/238 evaluated as "Not Acceptable." TSE 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 carrier/tracer has already been added to the sample.
K. NCR 24-15: ERA September MRAD-41 water study Fe-55 evaluated as "Not Acceptable."
TSE reported 615 pCi/L and the known value returned at 1230 pCi/L (range 723-1790). The root cause is still under investigation.
L. NCR 24-16: MAPEP August 24-MaS51 soil study Fe-55 evaluated as "Not Acceptable." TBE did not report a value and the known value returned 780 Bq/Kg (range 546-1014). The root cause is still under investigation.
M. NCR 24-17: MAPEP August 24-RdV51 vegetation study Sr-90 evaluated as "Not Acceptable. " TSE reported 0.95 Sq/sample and the known value returned 2.39 Sq/sample (range 1.67-3.11). The root cause is still under investigation.
Additional details can be found in the report, "4th Quarter 2024 Quality Assurance Report,"
Teledyne Brown Engineering Environmental Services, 2024.
Annual Radiological Environmental Operating Report YEAR: 2024 Page 58 of 60, Cross Check Intercom arison Pro ram TLD Annual QA Status Report EXECUTIVE
SUMMARY
Routine quality control (QC) testing was performed for dosimeters issued by the Environmental Dosimetry Company (EDC).
During this annual period 100% (72/72) of the individual dosimeters, evaluated against the EDC internal performance acceptance criteria (high-energy photons only), met the criterion for accuracy and 100%
(72/72) met the criterion for precision. In addition, 100% (12/12) of the dosimeter sets evaluated against the internal tolerance limits met EDC acceptance criteria and 100% of independent testing passed the performance criteria.
One internal assessment was performed in 2024. There were no findings. Additional details can be found in the Environm,ental Dosimetry Company, 2024 Annual Quality Assurance Status Report.
Annual Radiological Environmental Operating Report j YEAR: 2024 I Page 59 of 60 Company: Entergy Operations1 Inc.
I Plant: Grand Gulf Nuclear Station Direct Radiation Dosimetry Results, Environmental Direct Radiation Dosimetry Results Normalized Quarterly Monitoring Quarterly Facility Dose, Quarterly Bg+
Data, Mg Fg=Mg*Bg Annual BA+
Annual Annual Facility Dose, Monitoring
- Baseline, MDDg (mrem)
(mrem, or "ND" If f g S MDDg)
- Baseline, MDD11 Monitoring F11=M11-B11 Location Bg B11 Data, M11 (mrem, or "ND" If (mrem)
(mrem) 1 2
3 4
1 2
3 4
(mrem)
(mrem)
(mrem)
F11S MDD11)
M-01 15.0 20.0 14.2 15.3 15.2 14.3 ND ND ND ND 60.0 70.0 59.0 ND M-07 13.9 18.9 14.1 13.4 13.7 13.2 ND ND ND ND 55.5 65.5 54.3 ND M-09 13.1 18.1 13.9 13.2 13.6 12.9 ND ND ND ND 52.3 62.3 53.5 ND M-10 12.0 17.0 12.0 11.8 12.1 11.2 ND ND ND ND 48.1 58.1 47.1 ND M-14 14.2 19.2 14.2 13.7 14.3 13.5 ND ND ND ND 56.7 66.7 55.8 ND M-16 14.1 19.1 14.5 14.1 14.2 14.1 ND ND ND ND 56.2 66.2 56.8 ND M-19 12.7 17.7 12.7 12.6 12.7 13.9 ND ND ND ND 50.7 60.7 51.9 ND M-21 15.2 20.2 15.3 15.2 15.6 14.8 ND ND ND ND 60.9 70.9 60.8 ND M-22 11.6 16.6 11.9 11.9 11.9 12.5 ND ND ND ND 46.5 56.5 48.2 ND M-23 11.8 16.8 12.3 12.1 12.4 11. 7 ND ND ND ND 47.6 57.6 48.5 ND M-25 11.7 16.7 12.4 10.1 11.9 11.2 ND ND ND ND 46.3 56.3 45.6 ND M-28 14.3 19.3 14.2 13.5 14.7 14.0 ND ND ND ND 57.0 67.0 56.4 ND M-31 12.0 17.0 16.1 12.6 13.7 14.0 ND ND ND ND 47.9 57.9 56.4 ND M-33 15.0 20.0 15.4 15.6 14.5 14.6 ND ND ND ND 60.0 70.0 60.0 ND M-36 11.8 16.8 11.8 12.1 11.7 11.4 ND ND ND ND 47.3 57.3 46.9 ND M-38 12.9 17.9 13.2 12.6 12.4 12.5 ND ND ND ND 51.6 61.6 50.7 ND M-39 12.3 17.3 13.1 12.5 12.7 12.6 ND ND ND ND 49.5 59.5 50.9 ND M-40 8.5 13.5 9.5 8.7 8.9 9.1 ND ND ND ND 34.3 44.3 36.2 ND M-48 13.5 18.5 13.5 13.0 13.5 12.9 ND ND ND ND 53.9 63.9 53.0 ND M-49 14.4 19.4 14.7 14.3 14.7 14.3 ND ND ND ND 57.8 67.8 57.9 ND M-50 13.2 18.2 14.0 13.6 14.1 13.0 ND ND ND ND 52.6 62.6 54.7 ND M-55 14.5 19.5 16.2 14.7 15.2 14.3 ND ND ND ND 58.1 68.1 60.4 ND
Annual Radiological Environmental Operating Report I YEAR: 2024 I Page 60 of 60 Company: Entergy Operations, Inc.
I Plant: Grand Gulf Nuclear Station Direct Radiation Dosimetry Results Normalized Quarterly Monitoring Quarterly Ba+
Data, Ma Monitoring
- Baseline, MDDa (mrem)
Location Ba (mrem)
(mrem) 1 2
3 4
M-57 15.0 20.0 15.2 15.3 15.0 14.3 M-94 13.7 18.7 13.7 13.1 14.0 15.7 M-95 10.3 15.3 10.7 10.1 10.6 10.3 M-96 11.6 16.6 13.4 13.8 12.7 12.3 M-97 10.9 15.9 11.3 11.3 11.2 11.0 M-98 14.9 19.9 15.1 14.5 15.2 15.1 M-99 15.6 20.6 15.5 15.6 16.0 15.8 M-100 14.0 19.0 13.9 14.1 14.0 15.1 MDDo = Quarterly Minimum Differential Dose = 5 mrem MDDA = Annual Minimum Differential Dose= 10 mrem Quarterly Facility Dose, Fa=Ma-Ba (mrem, or "ND" if Fa S MDDa) 1 2
3 4
ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND= Not Detected, where Mo~ (Bo+MDDo) or MA~ (BA+MDDA)
Annual BA+
- Baseline, MDDA BA (mrem)
(mrem) 59.9 69.9 54.7 64.7 41.2 51.2 46.3 56.3 43.6 53.6 59.5 69.5 62.3 72.3 55.8 65.8 Annual Monitoring Data, MA (mrem) 59.8 56.4 41.7 52.1 44.8 59.9 62.9 57.1 Annual Facility Dose, FA=MA-BA (mrem, or "ND" If FASMDDA)
ND ND ND ND ND ND ND ND