ML22131A134

Annual Radiological Environmental Operating Report for 2021

ML22131A134
Person / Time
Site:	Sequoyah
Issue date:	05/11/2022
From:	Marshall T Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Material Safety and Safeguards, Office of Nuclear Reactor Regulation
References
Download: ML22131A134 (59)

Text

1\14 TENNESSEE VALLEY AUTHORITY Sequoyah Nuclear Plant, Post Office Box 2000, Soddy Daisy, Tennessee 37384 May 11, 2022 10 CFR 50.4 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D. C. 20555-0001 Sequoyah Nuclear Plant, Units 1 and 2 Renewed Facility Operating License Nos. DPR-77 and DPR-79 NRC Docket Nos. 50-327, 50-328, and 72-034

Subject:

Annual Radiological Environmental Operating Report Enclosed is the Annual Radiological Environmental Operating Report for the period of January 1 to December 31, 2021. This report is being submitted as required by the respective Sequoyah Nuclear Plant (SON), Units 1 and 2, Technical Specification 5.6.1 and SON's Offsite Dose Calculation Manual Administrative Control Section 5.1, each of which specifies that the report be submitted prior to May 15th of each year.

There are no new regulatory commitments contained in this letter. If you have any questions concerning this matter, please contact Mr. Jeffrey Sowa, SON Licensing Manager, at (423) 843-8129.

Respectfully, Marshall, Digitally signed by Marshall, Thomas B.

Thomas B. Date: 2022.05.11 08:09:36

-04'00' Thomas Marshall Site Vice President Sequoyah Nuclear Plant

Enclosure:

Annual Radiological Environmental Operating Report, Sequoyah Nuclear Plant, 2021 cc (Enclosure):

NRC Regional Administrator- Region II NRC Resident Inspector- Sequoyah Nuclear Plant

ENCLOSURE ANNUAL RADIOLOGICAL ENVIRONMENTAL OPERATING REPORT SEQUOYAH NUCLEAR PLANT 2021

2021 Annual Radiological Environmental Operating Report Tennessee Valley Authority Sequoyah Nuclear Plant May 2022 Prepared under contract by Chesapeake Nuclear Services, Inc. and GEL Laboratories, LLC

[ijij* I Laboratories LLc a member of The GEL Group INC

TABLE OF CONTENTS Executive Summary .. .. .. ...... ...... ... .......... ........ .... .. ...... .. .... ..... .. .. .. ...... .... .... .... ... .. .... .. .. ............ ......... .. .... ........ . 1 Introduction ................................... ................ ............................................................................................... 2 Naturally Occurring and Background Radioactivity ............................................................................... ... 2 Electric Power Production ... ............. .. ........ ........ ............. .......... ........ ......... .. .. .......... ... ... ... .......... .. ..... ... .... 3 Site and Plant Description .................. .. .. ........... .............. .... .. ... .. .... ................ ... .... ... ..... ..................... ........... 5 Radiological Environmental Monitoring Program ........................................................................................ 7 Direct Radiation Monitoring ........ .. .. .. ............................. .. .... ... .. .. .............. .... ...... ...... ..... .. .. ... ........ ............. 10 Measurement Techniques ... .. .. .. ...... ................. ......... ...... ..... ....... ...... ....... ..... ... ... ... .... ........... ... ........ ... ... 10 Results ..................................................................................................................................................... 10 Atmospheric Monitoring ............................................................................................................................. 13 Sample Collection and Analysis .............. .... .. ....... .................... .... ...... ..... .. .. ...... .. .... .......... ....... .. ...... ....... 13 Results .......... ... ....... .............. .. .. ... ... ..... ..................... ........... ............. ....... ........ ... .................. ........... ....... . 13 Terrestrial Monitoring .......... ...... ......................... ...... ... ... ..... ........ ....... ... ..... ... ..... ........ ....... ... ...... ............ .... 15 Sample Collection and Analysis .............................................................................................................. 15 Results ............................................................................................ .. ....................................................... 15 Liquid Pathway Monitoring ............... ........... ....... ........ .. ... ...... ...... .... ...... ....... ........ ...... .... ...... ...... .......... ...... 17 Sample Collection and Analysis .................... ....... ... .... .... ......... .... .. .... ..... .. .. .. .... .. .. .. ............ ... .. .. ... ... .... .. . 17 Results .......... ... ............... .. ........ ...... .......................... ........... ............. ....... ........ ... ..................... ........ ........ 17 Assessment and Evaluation ........................................................................................................................ 19 Results ............. ................................................................................. ............................................... ........ 19 Conclusions ......... ....... ..... ................ ........ .... .. .......... ........ ....... ...... ...... ....... .. ........ ...... ........ ..... .. .. .. .... .... .. . 19 References .. ..... ................... ... ..... ... .................... ... ... ... ....... ...... ....... ........ ..................... ... ........ ....... ...... ....... 20 Appendix A Radiological Environmental Monitoring Program and Sampling Locations ....................... 21 Appendix B Program Modifications ................................................................ ....................................... 31 Appendix C Program Deviations ...................................................... ....... ................ ................................ 33 Appendix D Analytical Procedures .. .......... ..... .. ........ .... .... .. ... ... ....... ............ ...... .... ..... .. ................ .. ... ... .. 35 Appendix E Lower Limits Of Detection ..... ....................................... .................. ........................ ....... ..... 37 Appendix F Quality Assurance/ Quality Control Program ..................................................................... 41 Appendix G Land Use Census ................................................................................................................. 44 Appendix H Data Tables and Figures ................ .... ........ ....................... ...... .... .. ... ........ ... ........... .... .. .... .... 47 Appendix I Errata to Previous Annual Environmental Operating Reports ......................... .. .. ... .. ...... .... 54 2021 Sequoyah AREOR [i]

EXECUTIVE SUM MARY This report describes the Radiological Environmental Monitoring Program (REMP) conducted by the Tennessee Valley Authority (TVA) for the Sequoyah Nuclear Plant (SQN) during the 2021 monitoring period. The program is conducted in accordance with regulatory requirements to monitor the environment per 10 CFR 20, 10 CFR 50, applicable NUREGs (U.S. NRC, 1991) and TVA procedures (TVA, 2018). The REMP includes the collection and subsequent determination of radioactive material content in environmental samples. Various types of samples are collected within the vicinity of the plant, including air, water, food crops, soil, fish, and shoreline sediment; and direct radiation levels are measured. The radiation levels of these samples are measured and compared with results from control stations, which are located outside the plant's near vicinity, and with environmental data collected at Sequoyah Nuclear Plant prior to operations (preoperational data). This report contains an evaluation of the results from this monitoring program and resulting potential impact of SQN operations on the environment and the general public.

All environmental samples in support of the REMP were collected by TVA and/or contractor personnel.

All environmental media were analyzed by GEL Laboratories, LLC except for environmental dosimeters, which were analyzed by Landauer. The evaluation of all results and the generation of this report were performed by Chesapeake Nuclear Services, Inc. and GEL Laboratories.

There was no detectable increase in the background direct radiation levels normally observed in the areas surrounding the plant, as measured by environmental dosimeters. In 2021, trace quantities of cesium-137 (Cs-137) were measured in most soil samples from both indicator and control locations. The concentrations were typical of the levels expected to be present in the environment from past nuclear weapons testing. The fallout from accidents at the Chernobyl plant in the Ukraine in 1986 and the Fukushima plant in Japan in 2011 were also potential contributors to the low levels of Cs-137 and Sr-90 measured in environmental samples. There was no identified increase in Cs-137 and Sr-90 levels attributed to Sequoyah.

Tritium (H-3) was detected in some public drinking water samples, from both control and indicator locations. The measured tritium levels were very low and a small fraction (less than 10%) of the EPA drinking water limit. Gross beta was also identified some drinking water and groundwater samples. The gross beta levels were low, and at levels that can be attributed to natural radiation . Only naturally occurring radioactivity was identified in wet vegetation, fish, food products and shoreline sediment samples.

In summary, the measured levels of radioactivity in the environmental samples are considered representative of background levels; there were no detectable levels attributable to the operations of the Sequoyah Nuclear Plant.

2021 Sequoyah AREOR [1]

INTRODUCTION This report describes and summarizes the results of radioactivity measurements made in the vicinity of SQN and laboratory analyses of samples collected in the area . The measurements are made to comply with the requirements of 10 CFR 50, Appendix A, Criterion 64 and 10 CFR 50, Appendix I, Section IV.B.2, IV.B.3 and IV.C to determine potential effects on public health and safety. This report satisfies the annual reporting requirements of SQN Technical Specification 5.6.1 and Offsite Dose Calculation Manual (ODCM)

Administrative Control 5.1. In addition to reporting the data prescribed by specific requirements, other information is included to correlate the significance of results measured by this monitoring program to the levels of environmental radiation resulting from naturally occurring radioactive materials.

Naturally Occurring and Background Radioactivity Most materials in our world today contain trace amounts of naturally occurring, primordial radioactivity.

Potassium-40 (K-40), with a half-life of 1.3 billion years, is a common radioactive element found naturally in our environment. Approximately 0.01 percent of all potassium is radioactive potassium-40. Other examples of naturally occurring radioactivity are beryllium-7 (Be-7), bismuth-212 and 214 (Bi-212 and Bi-214), lead-210 and 214 (Pb-210 and Pb-214), thallium-208 (Tl-208), actinium-228 (Ac-228), uranium-235 and uranium-238 (U-235 and U-238), thorium-234 (Th-234), radium-226 (Ra-226), radon-220 and radon-222 (Rn-220 and Rn-222), carbon-14 (C-14), and hydrogen-3 (H-3, commonly called tritium). These naturally occurring radioactive elements are in the soil, our food, our drinking water, and our bodies.

Radiation emitted from these materials make up part of low-level natural background radiation exposures. Radiation emitted from cosmic rays is the remainder.

It is possible to get an idea of the relative hazard of different types of radiation sources by evaluating the amount of radiation the U.S. population receives from each general type of radiation source. The information in Table 1 is primarily adapted from the U.S. Nuclear Regulatory Commission (U .S. NRC, February 1996) and National Council on Radiation Protection (NCRP, March 2009).

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Table 1 - U.S. General Population Average Dose Equivalent Estimates Source millirem {mrem); per year per person Natural Background Dose Equivalent Cosmic 33 Terrestrial 21 In the body 29 Radon 228 Total 311 Medical {effective dose equivalent) 300 Nuclear energy 0.28 Consumer Products 13 TOTAL 624.28

One-thousandth of a Roentgen Equivalent Man (rem). By comparison, the NRC's annual radiation dose limit for the public from any licensed activity, such as a nuclear plant, is 100 mrem.

As can be seen from the data presented above, natural background radiation dose equivalent to the U.S.

population is typically several thousand times higher than that normally received from nuclear plants.

This perspective illustrates that routine nuclear plant operations result in population radiation doses that are small fractions of the dose from natural background radiation. As Table 1 shows, the use of radiation and radioactive materials for medical uses results in an effective dose equivalent on average to the U.S.

population that is essentially the same as that caused by natural background cosmic and terrestrial radiation.

Electric Power Production Nuclear power plants are similar in many respects to conventional coal burning (or other fossil fuel) electrical generating plants. The basic process behind electrical power production in power plants is that fuel is used to heat water to produce steam, which provides the force to turn turbines and generators. In a nuclear power plant, the fuel is uranium and the heat is produced in the reactor through the fission of the uranium. Nuclear plants include many complex systems to control the nuclear fission process and to safeguard against the possibility of reactor malfunction. The nuclear reactions produce radionuclide byproducts, commonly referred to as fission and activation products. Small amounts of these fission and activation products are released into the plant systems. This radioactive material can be transported throughout plant systems and some of it may be released to the environment in an authorized and controlled manner.

Paths through which radioactivity from a nuclear power plant is routinely released are monitored. Liquid and gaseous effluent monitors record the radiation levels for each release. These monitors also provide alarm mechanisms to prompt termination of any abnormal releases before limits are exceeded.

2021 Sequoyah AREOR [3]

Releases are monitored at the onsite points of release. The radiological environmental monitoring program, which measures the environmental radiation in areas around the plant, provides a confirmation that releases are being properly controlled and monitored in the plant and that any resulting levels in the environment are within the established regulatory limits and a small fraction of the natural background radiation levels. In this way, the release of radioactive materials from the plant is tightly controlled, and verification is provided that the public is not exposed to significant levels of radiation or radioactive materials as the result of plant operations.

The SQN ODCM, which describes the program required by the plant technical specifications, prescribes limits for the release of radioactive effluents, as well as limits for doses to the general public from the release of these effluents.

The NRC's annual dose limit to a member of the public for all licensees is 100 mrem . The NRC's regulations for nuclear power plants require implementing a philosophy of "as low as reasonably achievable," where the dose to a member of the public from radioactive materials released from nuclear power plants to unrestricted areas is further limited on a per unit operating basis to the following:

Liquid Effluents Total body ~ 3 mrem/yr Any organ ~ 10 mrem/yr Gaseous Effluents Noble gases:

Total body ~ 5 mrem/yr Gamma air ~ 10 mrad/yr Beta air ~ 20 mrad/yr Particulates:

Any organ ~ 15 mrem/yr In addition to NRC's regulations, the EPA standard for the total dose to the public in the vicinity of a nuclear power plant, established in the Environmental Dose Standard of 40 CFR 190, is as follows:

Total body ~ 25 mrem/yr Thyroid ~ 75 mrem/yr Any other organ ~ 25 mrem/yr Table E-1 of this report presents a comparison of the nominal lower limits of detection (LLD) for the SQN monitoring program with the regulatory limits for maximum annual average concentration released to unrestricted areas. The table also includes the concentrations of radioactive materials in the environment that would require a special report to the NRC. It should be noted that the levels of radioactive materials in the environmental samples are typically not detected, being below the required detection level, with only naturally occurring radionuclides having measurable levels.

2021 Sequoyah AREOR [4]

SITE AND PLANT DESCRIPTION Sequoyah is located on a site near the geographical center of Hamilton County, Tennessee, on a peninsula on the western shore of Chickamauga Lake at Tennessee River Mile (TRM) 484.5 . Figure 1 shows the site in relation to other TVA projects. The SQN site, containing approximately 525 acres, is approximately 7.5 miles northeast of the nearest city limit of Chattanooga, Tennessee, 14 miles west-northwest of Cleveland, Tennessee, and approximately 31 miles south-southwest of TV A's Watts Bar Nuclear Plant (WBN) site.

Population is distributed unevenly within 10 miles of the SQN site. Approximately 60 percent of the population is in the general area between 5 and 10 miles from the plant in the sectors ranging from the south, clockwise, to the northwest sector. This concentration is a reflection of suburban Chattanooga and the town of Soddy-Daisy. This area is characterized by considerable open land with scattered residential subdivisions. Residential subdivision growth has continued within the 10-mile radius of the plant. There is also some small-scale farming located within 5 miles of the plant.

Chickamauga Reservoir is one of a series of highly controlled multiple-use reservoirs located on the Tennessee River whose primary uses are flood control, navigation, and the generation of electric power.

Secondary uses include industrial and public water supply, commercial fishing, and recreation. Public access areas, boat docks, and residential subdivisions have been developed along the reservoir shoreline.

SQN consists of two pressurized water reactors. Fuel was loaded in Unit 1 on March 1, 1980, and the unit achieved criticality on July 5, 1980. Fuel was loaded in Unit 2 in July 1981, and the unit achieved initial criticality on November 5, 1981.

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Figure 1 - Tennessee Valley Region LOUIS\lllL E w V A.

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2021 Sequoyah AREOR [6]

RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM By design, the radiation and radioactive materials generated in a nuclear reactor are contained within the reactor and plant support systems. There are planned routine releases from these plant systems, but plant effluent radiation monitors are designed to monitor these releases to the environment.

Environmental monitoring is a final verification that the systems are performing as designed and planned .

The monitoring program is designed to monitor the pathways between the plant and the people in the immediate vicinity of the plant. Sample types are chosen so that the potential for detection of radioactivity in the environment will be maximized. The Radiological Environmental Monitoring Program (REMP) and sampling locations for SQN are outlined in Appendix A.

There are two primary pathways by which radioactivity can move through the environment to humans:

air and water (reference Figure 2). The air pathway can be separated into two components: the direct (airborne) pathway and the indirect (ground or terrestrial) pathway. The direct airborne pathway consists of direct radiation and inhalation by humans. In the terrestrial pathway, radioactive materials may be deposited on the ground, with direct exposure to individuals, and/or uptake by plants and then subsequently ingested by animals and/or humans. Human exposure through the liquid pathway may result from drinking water, eating fish, or by direct exposure at the shoreline. The types of samples collected in this program are designed to monitor these pathways.

Many factors were considered in determining the locations for collecting environmental samples. The locations for the atmospheric monitoring stations were determined from a critical pathway analysis based on weather patterns, dose projections, population distribution, and land use. Terrestrial sampling stations were selected after reviewing the local land uses, including the locations of dairy animals and gardens in conjunction with the air pathway analysis. Liquid pathway stations were selected based on dose projections, water use information, and availability of media such as fish and sediment. Table A-2 lists the sampling stations and the types of samples collected. Modifications made to the SQN monitoring program are reported in Appendix B. Deviations to the sampling program are included in Appendix C.

To determine the amount of radioactivity in the environment prior to the operation of SQN, a preoperational radiological environmental monitoring program was initiated in 1971 and operated until the plant began operation in 1980. Measurements of the same types of radioactive materials that are measured currently were assessed during the preoperational phase to establish normal background levels for various radionuclides in the environment.

The preoperational monitoring program is a very important part of the overall program. During the 1950s, 1960s, and 1970s, atmospheric nuclear weapons testing released radioactive material to the environment causing increases in background radiation levels. Knowledge of preexisting radionuclide patterns in the environment permits a determination, through comparison and trending analyses, of any increase attributable to SQN operation .

The determination of environmental impact during the operating phase also examines changes in the background that may be attributable to sources other than SQN . This potential contribution is determined with control stations that have been established in the environment outside any likely influence from the plant. Results of environmental samples taken at control stations (far from the plant) are compared with 2021 Sequoyah AREOR [7]

those from indicator stations (near the plant) to aid in the determination of any contribution from SQN operation.

In 2021 the sample analyses were performed by the contracted laboratory, GEL Laboratories, LLC, based in Charleston, SC. Analyses were conducted in accordance with written and approved procedures and are based on industry established standard analytical methods. A summary of the analysis techniques and methodology is presented in Appendix D.

As shown in Table E-1, the analytical methods used to determine the radionuclide content of samples collected in the environment are sensitive and capable of detecting small amounts of radioactivity. The sensitivity of the measurement process is defined in terms of the lower limit of detection (LLD). A description of the nominal LLDs for the Radioanalytical Laboratory is presented in Appendix E.

The laboratory applies a comprehensive quality assurance/quality control program to monitor laboratory performance throughout the year. One of the key purposes of the QA/QC program is to provide early identification of any problems in the measurement process so they can be corrected in a timely manner.

This program includes instrument checks, to ensure that the radiation measurement instruments are working properly, and the analysis of quality control samples. As part of an interlaboratory comparison program, the laboratory participates in a blind sample program administrated by Eckert & Ziegler Analytics. A complete description of the quality control program is presented in Appendix F.

An annual land use census is conducted for the purpose of identifying changes in the land uses around the plant and potential for changes in exposure pathways and locations. Appendix G contains the results of the annual land use census. Data tables summarizing the sample analysis results are presented in Appendix H. Finally, Appendix I contains any errata from previous AREORs.

2021 Sequoyah AREOR [8]

Figure 2 - Environmental Exposure Pathways ENVIRONMENTAL EXPOSURE PATHWAYS DF MAN DUE TD RELEASES DF RADIOACTIVE MATERIAL TD THE ATMOSPHERE AND LAKE.

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Diluted By Atmosphere Airborne Releases D {\

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Liquid Releases Diluted By Lake MAN Animals (Milk.Meat) I.__ _ _~

Consum~By Man ~Shoreline 0 Exposure Consumed '\\

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~___,I Fish Vegetation Uptake From Soil l.________ -1 2021 Sequoyah AREOR [9]

DIRECT RADIATION MONITORING Direct radiation levels are measured at various monitoring points around the plant site . These measurements include contributions from cosmic radiation, radioactivity in the ground, fallout from atmospheric nuclear weapons tests conducted in the past, and any radioactivity that may be present from plant operations. Any plant contribution to the total direct radiation component is small compared to that from background. Therefore, an in-depth analysis, comparing the variation in measurements and the background fluctuation, is undertaken to identify any significant plant contribution. This process is further described below.

Measurement Techniques The Landauer lnlight environmental dosimeter is used in the radiological environmental monitoring program for the measurement of direct radiation . This dosimeter contains four elements consisting of aluminum oxide detectors with open windows as well as plastic and copper filters. The dosimeter is processed using optically stimulated luminescence (OSL) technology to determine the amount of radiation exposure.

The dosimeters are placed approximately one meter above the ground, with two at each monitoring location. Sixteen monitoring points are located around the plant near the site boundary, one location in each of the 16 compass sectors. One monitoring point is also located in each of the 16 compass sectors at approximately four to five miles from the plant.

Dosimeters are also placed at additional monitoring locations out to approximately 32 miles from the site.

The dosimeters are exchanged every three months. The dosimeters are sent to Landauer for processing and results reporting. The values are corrected for transit and shielded background exposure. An average of the two dosimeter results is calculated for each monitoring point. The environmental dosimetry program is conducted in accordance with the specifications outlined in American National Standards Institute (ANSI) and Health Physics Society (HPS) ANSI/HPS NB.37-2014 (Health Physics Society, 2014) for environmental applications of dosimeters.

Results For reporting dose, all results for environmental dosimeter measurements are normalized to a standard quarter (91 days). In general, two direct radiation measurements are taken in each meteorological sector:

one "inner ring" location within approximately 2 miles from the plant, and one "outer ring" location approximately 5 miles from the plant. In addition, control dosimeters are placed at locations further from the plant (approximately 10 - 30 miles) .

Beginning in 2021, the SQN environmental dosimeters were evaluated in compliance with ANSI NB.37-2014. The process of this evaluation is summarized below:

1. The average field dosimeter result is determined for each location and normalized to a standard quarter (91 days)

2. The field result is adjusted by the transit and shield (storage) dose to determine the net dose at each location. This is performed at each location for each quarter, and the four quarters are summed to determine the annual net dose.

2021 Sequoyah AREOR [10]

3. The quarterly and annual historical average net dose were determined for each monitoring location, based on data from 2017 - 2021.

4. The standard deviation of each historical net dose was calculated, to determine the 90 th percentile standard deviation for both the quarterly and annual results.

5. The 2021 quarterly and annual net doses are compared to the historical averages (plus 3 times the 90 th percentile standard deviation, also known as the minimum differential dose) to determine if any facility related dose was identified at any location during any quarter or the year.

The result of the evaluation of environmental dosimeters is that there is no facility related dose measured in the environment around Sequoyah (see Table 2) . There were no quarterly or annual dosimeters that exceeded the historical baseline plus the calculated minimum differential dose. The dosimeters from location SSE-2, in the 2nd quarter, were not found during dosimeter change out, so no measurement was recorded for that location and time period . An average quarterly value was assumed, however, for determination of the annual exposure at this location.

The difference in onsite (< 2 miles) and offsite (> 2 miles) averages is consistent with levels measured for the preoperational and construction phases of TVA nuclear power plant sites, where the average levels onsite were slightly higher than levels offsite. Figure 3 compares plots of the data from the the onsite stations with those from the offsite stations over the period from 1977 through 2021. Landauer In light Optically Stimulated Luminescence (OSL) dosimeters have been deployed since 2007, replacing the Panasonic UD-814 dosimeters used during the previous years. In order to implement the methodology of ANSI N13.37-2014, the dose received by dosimeters in shielded storage that are used as unexposed controls was determined. This in turn was used to account for the extraneous dose that should be removed from the gross measurements as measured by the field dosimeters.

Figure 3 - Direct Radiation SQN Direct Radiation Four Quarter Rolling Average 24.0 ~-------------------------------~

Initial SONP operation In July ,

1980 lnlight Dosimeter Deployment in January,

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197 5 1980 1985 1 990 1995 2000 2005 2010 2015 2020 O n -Site ~ Off-Site 2021 Sequoyah AREOR [11]

Table 2 - Sequoyah Environmental Dosimeters Quarterly 2021 Quarterly Results Quarterly Net Dose Annual Annual Annual Net M ap Land. Direction Distance Baseline (mrem/qtr) (mrem/qtr) Base line Dose Dose Location ldent. Station Description (deg) (miles) (mrem/qtr) 1 2 3 4 1 2 3 4 (mrem/yr) (mre m) (mrem/yr) 14 1 NW-3 320 20.0 11.9 10.2 9.0 10.5 11.0 ND ND ND ND 47.8 40.6 ND 8 2 W- 3 PM -3 SQN 280 5.6 12.6 11.8 10.4 12.3 11.8 ND ND ND ND 50.4 46.2 ND 78 3 WSW-3 Crab t ree Rd 248 5.7 16.1 16.4 16.9 12.9 11.3 ND ND ND ND 64.4 57.5 ND 79 4 WSW-4 Love Lane 244 7.8 13.0 13.4 12.2 11.9 11.8 ND ND ND ND 52. 1 49.4 ND 7 5 SW-2 PM-2 SQN 227 3.8 13.7 11.8 12.7 11.8 12.8 ND ND ND ND 54.7 49.0 ND 77 6 WSW- 2 Be n Ha l l ; Th rasher La n e 238 2.5 11.1 11.0 9.0 9.5 11.3 ND ND ND ND 44.3 40.7 ND 10 7 WSW-2A PM-9 SQN 250 2.6 13.0 14.5 10.8 10.3 10.8 ND ND ND ND 52.0 46.3 ND 76 8 WSW- 1 #1, S of Trai n i ng Cen te r Rd 241 0.9 17.1 14.8 14.5 11.5 14.8 ND ND ND ND 68.3 55.6 ND 75 9 SW-1 #9 EDS 228 0.7 17.9 15.9 17.8 15.4 14.8 ND ND ND ND 71.6 63.9 ND 81 10 W-1 #2 Tra ini ng Ct r Rd/ Igou Fe rry 260 0.6 20.4 18.1 21.0 20.4 18.9 ND ND ND ND 81.4 78.4 ND 83 11 WNW-1 SQN En t rance, S 292 0.4 16.0 15.4 14.1 14.4 14.8 ND ND ND ND 64.0 58.7 ND 73 12 SSW- 1 #29 Igou Ce me t ery 203 0.6 16.1 14.8 14.1 15.3 13.5 ND ND ND ND 64.2 57.6 ND 57 13 ENE- 1 #3 4 E. of Coo l i ng Cana I 73 0.2 14.0 12.6 12.2 12.8 13.5 ND ND ND ND 56.2 51.1 ND 85 14 NW- 1 #4 SQN Ent rance; N 315 0.4 17.2 17.5 15.7 19.8 16.3 ND ND ND ND 68.7 69. 3 ND 87 15 NNW-1 #3 St ones age Rd 344 0.6 16.4 15.7 11.1 16.8 17.6 ND ND ND ND 65.6 61.1 ND 49 16 N-1 #13 Near LM*2 SQN 3 0.6 16.0 12.3 14.1 11.3 16.8 ND ND ND ND 63.8 54.4 ND 88 17 NNW-2 Shady Grove Commun ity 342 1.7 13.0 11.8 13.9 10.8 12.0 ND ND ND ND 52.2 48.4 ND 82 18 W- 2 SQ Hea lth Cen t e r 275 4.3 11.0 11.0 8.3 10.8 7.8 ND ND ND ND 44. 1 37.8 ND 84 19 WNW- 2 Soddy-Daisy Fire Sta t io n 295 5.3 11.8 9.3 10.4 10.8 9.0 ND ND ND ND 47.2 39.5 ND 86 20 NW- 2 Soddy-Daisy Wa t er Filt . Pl ant 318 5.2 13.4 11.0 11.3 11.6 11.7 ND ND ND ND 53.7 45.5 ND 89 21 NNW- 3 Osage Drive 334 5.3 13.3 12.6 10.8 13.8 12.5 ND ND ND ND 53.3 49.7 ND 51 22 N-3 Lee Pike 358 5.2 13.5 11.0 10.8 12.3 11.0 ND ND ND ND 53.9 45.0 ND 52 23 N-4 Ra il road St., Sa le Creek 355 10.0 14.9 13.2 14.1 13.8 12.0 ND ND ND ND 59.8 53.0 ND 13 24 ESE- 3 RM-3 SQN 117 11.3 14.3 14.0 13.6 11.0 12.3 ND ND ND ND 57.3 50.8 ND 70 25 SSE-2 Snow Hi l l Rd 158 4.6 17.2 14.8 N/A 14.3 14.0 ND N/A ND ND 68.7 57.4 ND 68 26 SE- 4 Cross Rds . Chu rch 136 5.2 16.7 14.8 13.6 15.9 16.0 ND ND ND ND 66.7 60.3 ND 63 27 ESE-2 Oo l tewa h/G ' t own Pi ke 112 4.9 16.1 14.8 15.9 16.5 15.0 ND ND ND ND 64.4 62.2 ND 60 28 E- 2 Smith Fa rm 87 5.2 14.4 11.5 14.1 13.4 13.5 ND ND ND ND 57.7 52.5 ND 58 29 ENE-2 Ga mb le Rd., E 66 5.1 14.3 16.4 10.8 13.9 14.0 ND ND ND ND 57.1 55.1 ND 56 30 NE- 2 Ga mb l e Rd ., W 51 4.1 11.1 9.9 10.8 14.4 9.0 ND ND ND ND 44.5 44. 1 ND 53 31 NNE- 2 El dri dge Rd, W of Bi rch wood Pk 31 5.3 13.2 11.5 12.7 12.9 14.0 ND ND ND ND 52.9 51.0 ND 50 32 N- 2 Dogwood Drive 4 2.1 14.9 15.1 13.2 14.4 13.8 ND ND ND ND 59.8 56.4 ND 5 33 NNE- 1 LM-5 SQN 13 1.8 18.4 16.1 18.3 15.8 18.3 ND ND ND ND 73.6 68.4 ND 55 34 N E- 1 Bi rch wood Pike, N 38 2.4 15.1 14.8 14.1 13.9 14.5 ND ND ND ND 60.5 57.2 ND 4 35 N E- l A LM-4SQN 50 1.5 16.0 11.8 18.7 19.4 13.0 ND ND ND ND 64.0 62.9 ND 59 36 E- 1 IBEW 96 1.2 12.9 12. 3 12.4 13.6 13.3 ND ND ND ND 51.4 51.6 ND 62 37 ESE-1 La kes i de Rd 110 1. 2 14.2 12.9 12.0 15.1 13.3 ND ND ND ND 56.7 53.2 ND 66 38 SE- 1 Cha ttan ooga Wa te r Sk i Cl u b 131 1.4 11.2 10.4 9.4 8.0 10.3 ND ND ND ND 44.6 38.1 ND 67 39 SE- 2 Bi rch wood Pike, S 129 1.9 14.5 14.3 15.0 14.1 13.8 ND ND ND ND 58.1 57.1 ND 69 40 SSE- 1 Ha rri son Bay Rd, E 154 1.6 12.7 10.4 14.1 13.1 13.3 ND ND ND ND 50.8 50.8 ND 71 41 S- 1 Ha rri son Bay Rd 183 1.5 17.4 15.4 17.8 15.1 15.3 ND ND ND ND 69.7 63.5 ND 90 42 SSW - 18 En t rance to Ha milto n Is l and 192 1.5 12.3 10.4 15.0 10.5 11.3 ND ND ND ND 49.2 47.2 ND 3 43 SSW- l C Siren St a ti on 27, LM-3 SQN 198 2.0 13.6 11.3 15.1 12.3 12.8 ND ND ND ND 54.3 51.4 ND 74 44 SSW- 2 Ha rri so n Bay St a te Park 204 4.0 19.3 17.0 20.6 18.1 15.3 ND ND ND ND 77. 1 70.9 ND 72 45 S- 2 Ra msey Tow n Rd 185 4.7 12.5 12.1 10.8 12.1 9.8 ND ND ND ND 50.0 44.7 ND 9 46 SSW-3 PM-8SQN 203 8.7 15.6 11.8 16.4 14.3 15.8 ND ND ND ND 62.4 58.2 ND 11 47 SW- 3 RM-1 SQN 228 16.7 17.5 16.1 16.4 17.8 15.8 ND ND ND ND 70.1 66.0 ND 12 N N E-4 RM-2 SQN 32 17.8 15.2 13.4 16.3 16.0 18.1 ND ND ND ND 60.7 63.9 ND 2021 Sequoyah AREOR [12]

ATMOSPHERIC MONITORING The atmospheric monitoring network is divided into three groups identified as local, perimeter, and remote. Four local air monitoring stations are located on or adjacent to the plant site in the general directions of highest wind frequency. Four perimeter air monitoring stations are located between 6 to 11 miles from the plant, and two air monitors are located out to 15 miles and used as control or baseline stations. The monitoring program and the locations of monitoring stations are identified in the tables and figures of Appendix A.

Results from the analysis of samples in the atmospheric pathway are presented in Table H-1 through Table H-3. Radioactivity levels identified in this reporting period are consistent with background and preoperational program data. There is no indication of an increase in atmospheric radioactivity due to SQN operations.

Sample Collection and Analysis Air particulates are collected by continuously sampling air at a flow rate of approximately 2 cubic feet per minute (cfm) through a 2-inch glass fiber filter. The sampling system consists of a pump, a magnehelic gauge for measuring the pressure drop across the system, and a dry gas meter. This allows for an accurate determination of the volume of air passing through the filter. The sampling system is housed in a metal structure. The filter is contained in a sampling head mounted on the outside of the monitoring structure.

The filter is replaced weekly. Each filter is analyzed for gross beta activity at least 3 days after collection to allow time for the naturally occurring radon daughters to decay. Monthly composites of the filters from each location are analyzed by gamma spectroscopy.

Atmospheric radioiodine is collected using a commercially available cartridge containing triethylenediamine (TEDA)-impregnated charcoal. This system is designed to collect iodine in both the elemental form and as organic compounds. The cartridge is in the same sampling head as the air particulate filter and is downstream of the particulate filter. The cartridge is changed at the same time as the particulate filter and samples the same volume of air. Each cartridge is analyzed for radioiodines (1-131, -133, and -135) by gamma spectroscopy ..

Results The results from the analysis of air particulate samples are summarized in Table H-1. Gross beta activity levels in 2021 were consistent with levels reported in previous years. The annual average gross beta activity measured for air particulate samples was 0.036 pCi/m 3 for indicator locations and 0.037pCi/m 3 for control locations. The annual averages of the gross beta activity in air particulate filters at these stations for the period 1977-2021 are presented in Figure H-1. Increased levels due to fallout from atmospheric nuclear weapons testing are evident in the years prior to 1981 and a small increase from the Chernobyl accident can be seen in 1986. These patterns are consistent with data from monitoring programs conducted by TVA at other nuclear power plant sites. GEL Laboratories, LLC took over radiochemistry analysis for the SQN REMP program in 2017. Since that change, the air filter gross beta results increased from a long-term average of approximately 0.02 pCi/m 3 to approximately 0.03 pCi/m 3 .

This slight increase is the result of the new laboratory using a different calibration source (Tc-99) than the prior laboratory (Sr-90), which resulted in a slightly higher correlation of the instrument measurement to 2021 Sequoyah AREOR [13]

the corresponding calculated air concentration . The current results are consistent between indicator and control samples, and consistent with results from other nuclear power plant environmental monitoring programs.

As shown in Table H-2, 1-131 was not detected in any charcoal cartridge samples. Only natural radioactive materials were identified by the monthly gamma spectral analysis of the air particulate samples collected in 2021 (see Table H-3) .

2021 Sequoyah AREOR [14]

TERRESTRIAL MONITORING Terrestrial monitoring is accomplished by collecting samples of environmental media representing the transport of radioactive material from the atmosphere to the ground and various food products. For example, radioactive material may be deposited on vegetation and be ingested by consuming vegetables or it may be deposited on pasture grass where dairy cattle are grazing. When the cow ingests the radioactive material, some of it may be transferred to the milk and consumed by humans who drink the milk. Therefore, samples of milk, soil, and food crops are collected and analyzed to determine potential impacts from exposure through these pathways. The results from the analysis of these samples are shown in Table H-5 and Table H-6.

A land use census is conducted annually between April and October to identify the location of the nearest milk animal, the nearest residence, and the nearest garden of greater than 500 square feet producing fresh leafy vegetables in each of 16 meteorological sectors within 5 miles from the plant. This land use census satisfies the requirements 10 CFR 50, Appendix I, Section IV.B.3. The results of the 2021 land use census are presented in Appendix G.

Sample Collection and Analysis There is no milk pathway currently applicable to SQN. In previous years, there was a milk consumption pathway at one location applicable to SQN and was monitored via milk or vegetation samples at the location. Beginning in November 2019, wet vegetation samples in lieu of milk samples were taken from two control locations. There are no indicator samples, as there is no actual milk pathway in 2021. The land use census will continue to monitor if the milk pathway becomes applicable to SQN again.

Soil samples are collected annually from the area surrounding each air monitoring station. The samples are collected with either a "cookie cutter" or an auger type sampler. After drying and grinding, the sample is analyzed by gamma spectroscopy. When the gamma analysis is complete, the sample is analyzed for Sr-89 and Sr- 90, which require chemical processing prior to measurement.

Samples representative of food crops raised in the area near the plant are obtained from individual gardens. Types of foods may vary from year to year due to changes in the local vegetable gardens.

Samples of the same food products grown in areas that would not be affected by the plant were obtained from area produce markets as control samples. The edible portion of each sample is analyzed by gamma spectroscopy.

Results The wet vegetation (milk substitute) samples collected in 2021 did not identify any plant related radionuclides. The vegetation results are provided in Table H-4.

The gamma analysis of soil samples detected trace levels of Cs-137 at four indicator and two control locations. The concentrations of Cs-137 are consistent with levels previously reported from fallout. One indicator sample was positive for Sr-90 at 356 pCi/kg. All other radionuclides reported were naturally occurring isotopes. The soil analysis data are provided in Table H-5. The single highest soil radioactivity was from an indicator location sample (PM-8, Harrison, TN) at 405 pCi/kg for Cs-137.

2021 Sequoyah AREOR [15]

A plot of the annual average Cs-137 concentrations in soil is presented in Figure 4. The concentrations of Cs-137 in soil are steadily decreasing due to the cessation of weapons testing in the atmosphere, the 30-year half-life of Cs-137 and transport through the environment.

Radionuclides reported in food samples were all naturally occurring. Analysis of these samples indicated no contribution from plant activities. The results are reported in Table H-6.

Figure 4 -Average Cs-137 Soil Radioactivity Cs-137 Radioactivity in Soil Sequoyah 3.0 c:-

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-e- lndicator - control - - Preoperational Average 2021 Sequoyah AREOR [16]

LIQUID PATHWAY MONITORING Potential exposures from the liquid pathway can occur from drinking water, ingestion of edible fish, or from direct radiation exposure from radioactive materials deposited in shoreline sediment. The monitoring program included the collection of samples of surface water, groundwater, drinking water supplies, fish, and shoreline sediment. Samples from the reservoir are collected both upstream and downstream from the plant. Results from the analysis of aquatic samples are presented in Table H-7 through Table H-11.

Sample Collection and Analysis Samples of surface water are collected from the Tennessee River downstream and upstream of the plant using automatic sampling systems. A timer turns on the system at least once every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and the sample collects into a composite jug. A 1-gallon sample is removed from the composite jug each month and the remaining water in the jug is discarded. The monthly composite sample is analyzed for gamma-emitting radionuclides by gamma spectroscopy and gross beta analysis. A quarterly composite sample is analyzed for tritium by liquid scintillation counting.

Samples are collected by an automatic sampling system at the first downstream drinking water intake and at the water intake for the city of Dayton located approximately 20 miles upstream. At other selected locations, grab samples are collected from drinking water systems which use the Tennessee River as their source. These monthly samples are analyzed by gamma spectroscopy and gross beta analysis. A quarterly composite sample from each station is analyzed for tritium. Additional tritium analyses are performed on samples from two of the locations that are shared with the Watts Bar monitoring program. The sample collected at the water intake for the city of Dayton also serves as control sample for surface water.

Groundwater is sampled from an onsite well using an automatic composite sampler; and a grab sample is collected quarterly from a private well in an area unaffected by SQN. Samples from the wells are collected quarterly and analyzed by gamma spectroscopy and for gross beta and tritium activity.

Samples of commercial and game fish species are collected semiannually from each of two reservoirs: the reservoir on which the plant is located (Chickamauga Reservoir) and the upstream reservoir (Watts Bar Reservoir). The samples are collected using a combination of netting techniques and electrofishing.

Samples are prepared from filleted fish. After drying and grinding, the samples are analyzed by gamma spectroscopy.

Samples of shoreline sediment are collected from two downstream recreational use areas and one upstream location. The samples are dried and ground and analyzed by gamma spectroscopy.

Results There were no fission or activation product radionuclides identified from the gamma spectroscopy analyses performed on surface water samples. Tritium activity above the nominal LLD value was measured in some control location samples of surface water. The tritium concentrations in six monthly samples from the control location averaged 494 pCi/liter. These tritium concentrations represent a small fraction of the Environmental Protection Agency (EPA) drinking water limit of 20,000 pCi/liter. The values were consistent with previously reported values. A summary table of the results is shown in Table H-7.

2021 Sequoyah AREOR [17]

There were no fission or activation products identified by the gamma spectroscopy of drinking water samples. Tritium activity was identified in some drinking water samples. The tritium concentrations in six samples from the control location averaged 494 pCi/liter, and one sample from the indicator location was 1400 pCi/liter. These tritium levels represented a small fraction of the EPA drinking water limit of 20,000 pCi/liter. The values were consistent with previously reported values. Some samples were positive for gross beta, with indicator positive samples averaging 13.4 pCi/liter and a single control sample was positive at 24.1 pCi/liter. The gross beta results are consistent with past samples, where occasionally these samples are positive for gross beta. This is likely due to natural radioactivity, and not necessarily indicative of a contribution from the power plant. The results are shown in Table H-8.

No fission or activation products were detected by the gamma spectroscopy analyses performed on groundwater samples from the REMP monitoring locations. Tritium was not detected in any collected ground water samples. No gross beta activity was detected for indicator location samples, but gross beta was identified in the offsite well control location, averaging 8.21 pCi/liter. These gross beta levels are representative of the levels typically found in groundwater. The results from the analysis of groundwater samples are presented in Table H-9.

In 2021 game fish (largemouth bass) and commercial fish (channel catfish) were sampled and analyzed from both control and indicator locations. No fission or activation products were identified in any of the samples. The results are summarized in Table H-10.

No fission or activation products were detected by the gamma spectroscopy performed on shoreline sediment samples from the REMP monitoring locations. All other radionuclides reported were naturally occurring isotopes. Results from the analysis of shoreline sediment samples are shown in Table H-11.

2021 Sequoyah AREOR [18]

ASSESSMENT AND EVALUATION Results The results of the environmental monitoring program did not identify any increases in environmental levels attributable to plant operations. As stated earlier in the report, any increase in radiation dose to the public resulting from the operation of SQN is negligible, especially when compared to the dose from natural background radiation . The results from each environmental sample are compared with the concentrations from the corresponding control stations and appropriate preoperational and background data to determine influences from the plant.

Conclusions The 2021 radiological environmental monitoring program results demonstrate that exposures to members of the general public, which may have been attributable to SQN, are small fractions of regulatory limits and essentially indistinguishable from the natural background radiation . The radioactivity reported herein is primarily the result of fallout or natural background. Any activity, which may be present in the environment as a result of plant operations, does not represent a significant contribution to the exposure of members of the public. The results confirm that radioactive effluents from the plant are controlled, maintaining releases as low as reasonably achievable (ALARA) and to a small fraction of the limits for doses to members of the public.

2021 Sequoyah AREOR [19]

REFERENCES GEL. (2022). 2021 Annual Quality Assurance Report for the REMP.

Health Physics Society. (2014). ANSI/HPS N13.37 Environmental Dosimetry- Criteria for System Design and Implementation. Health Physics Society.

NCRP. (March 2009). Report No. 160, Ionizing Radiation Exposure of the Population of the United States.

NCRP, Washington, D.C.

TVA. (2018) . Sequoyah Nuclear Plant Offsite Dose Calculation Manual, Revision 63.

U.S. NRC. (1991) . NUREG-1301 Offsite Dose Calculation Manual Guidance: Standard Radiological Effluent Controls for Pressurized Water Reactors, Generic Letter 89-01, Supplement 1. Washington, D.C.:

USNRC. Retrieved from http://www.nrc.gov/docs/ML0910/ML091050061.pdf U.S. NRC. (February 1996). Instruction Concerning Risks from Occupational Exposure. USNRC, Washington, D.C.

2021 Sequoyah AREOR [20]

APPENDIX A RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM AND SAMPLING LOCATIONS 2021 Sequoyah AREOR [21]

APPENDIX A Table A Sequoyah Radiological Environmental Monitoring Program Exposure Pathway and/or Sample Number of Sam_ples and Locationsa Sampling and Collection Type and Frequency of Analysis Frequency

1. AIRBORNE

a. Particulates 4 samples from locations (in different sectors} Continuous sampler operation Analyze for gross beta radioactivity ~

at or near the site boundary (LM -2, 3, 4 and 5} with sample collection weekly 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> following filter change .

(more frequently if required by Perform gamma isotopic analysis on 4 samples from communities approximately 6- dust loading} each sample if gross beta> 10 times 10 miles from plant (PM-2, 3, 8 and 9} yearly mean of control sample.

Composite at least once per 31 days 4 samples from control locations > 10 miles (by location} for gamma from the plant (RM-1, 2, 3 and 4} spectroscopy.

b. Radioiodine Samples from same locations as air particulates Continuous sample operation 1-131 by gamma spectroscopy on with filter collection weekly. each sample.

c. Soil Samples from same location as air particulates Annually Gamma spectroscopy, Sr-89, Sr-90 annually

2. DIRECT

a. Dosimeters 2 or more dosimeters placed at or near the site Quarterly (once per 92 days} Gamma dose quarterly (at least boundary in each of the 16 sectors. once per 92 days}

2 or more dosimeters placed at stations located approximately 4 to 5 miles from the plant in each of the 16 sectors.

2 or more dosimeters in other locations of special interest.

2021 Sequoyah AREOR [22]

APPENDIX A Table A Sequoyah Radiological Environmental Monitoring Program (Continued)

Exposure Pathway and/or Sample Number of Sam_ples and Locations Sampling and Collection Type and Frequency of Analysis Frequency

3. WATERBORNE

a. Surface Water TRM 503.8 Collected by automatic Gross beta and gamma spectroscopy sequential-type samplerb with on each sample . Composite for TRM 483.4 composite samples collected tritium analysis at least once per 92 over a period of approximately days.

31 days.

b. Ground water 1 sample adjacent to the plant {Well #6) Quarterly {Once per 92 days) Gross beta, gamma spectroscopy, and tritium analysis of each sample.

1 sample from ground water source up gradient

{Farm HW).

c. Drinking Water 1 sample at the first potable surface water Monthly {once per 31 days) Gross beta and gamma scan of each supplies, downstream from the plant {TRM sample.

473.0). Composite for tritium once per 92 days.

1 sample at the next 2 downstream potable water systems {greater than 10 miles downstream) {TRM 469.9 and TRM 465.3) 1 sample at a control location {TRM 503.8)c

d. Shoreline Sediment TRM 485 Semi-Annually {at least once Gamma spectroscopy of each per 184 days) sample TRM 480 TRM 479 2021 Sequoyah AREOR [23]

APPENDIX A Table A Sequoyah Radiological Environmental Monitoring Program (Continued)

Exposure Pathway and/or Sample Number of Sam_ples and Locations Sampling and Collection Type and Frequency of Analysis Frequency

4. INGESTION

a. Milk N/A. As of 2017, the milk pathway is not Once per 15 days 1-131 and gamma spectroscopy on applicable to SQN. each sample. Sr-89 and Sr-90 quarterly.

b. Fish One sample of commercially important species Semi-Annually {at least once Gamma spectroscopy on edible and one sample of recreationally important per 184 days) portions species. One sample of each species from Chickamauga and Watts Bar Reservoirs.

c. Vegetationd Samples from farms producing milk but not Monthly {at least once per 31 1-131 analysis and gamma

{Pasturage and grass) providing a milk sample days) spectroscopy of each sample

d. Food Products 1 sample of each principal food products grown Annually at time of harvest. Gamma spectroscopy on edible at private gardens and/or farms in the The types of foods available for portions immediate vicinity of the plant. sampling will vary. Typically available foods may include:

1 sample of each of the same foods grown at

• Cabbage greater than 10 miles distance from the plant.

• Corn

• Green Beans

• Potatoes

• Tomatoes a Sample locations are shown on Figure A-1 through Figure A-3.

b Samples shall be collected by collecting an aliquot at intervals not exceeding 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> c The samples collected at TRMs 503.8 are taken from the raw water supply, therefore, the upstream surface water sample will be considered the control sample for drinking water d Vegetation sampling is applicable only for farms that meet the criteria for milk sampling and when milk sampling cannot be performed 2021 Sequoyah AREOR [24]

APPENDIX A Table A Sequoyah REMP Sampling Locations Map Location Distance Indicator (I) or Number* Station Sector (miles) Control (Cl Sam~les Collectedb 2 LM -2 N 0 .7 AP ,CF,S 3 LM-3 SSW 2.0 AP,CF,S 4 LM -4 NE 1.5 AP ,CF,S 5 LM-5 NNE 1.8 AP ,CF,S 7 PM-2 SW 3.8 AP,CF,S 8 PM-3 w 5.6 AP,CF,S 9 PM-8 SSW 8.7 AP,CF,S 10 PM-9 WSW 2.6 I AP,CF,S 11 RM-1 SW 16.7 C AP,CF,S 12 RM-2 NNE 17.8 C AP,CF,S 13 RM-3 ESE 11.3 C AP,CF,S 14 RM-4 NW 20.0 C AP,CF,S 19 Farm HW NW 1.2 we 24 Well No. 6 NNE 0.15 w 31 TRM 473 .0 10.7d PW (East Side Utilities)c 32 TRM 469 .9 13.8d PW (E . I. DuPont) 33 TRM 465.3 18.4d PW (Chattanooga) 35 TRM 503 .8 (Dayton) 20.ld C PW,SW 37 TRM 485 .0 1.3d C ss 38 TRM 483 .4 0.3 d SW 40 TRM 479 .0 4.7 d ss 44 TRM 480.0 3.7 d ss 46 Chickamauga Reservoir F (TRM 471-530) 47 Watts Bar Reservoir C F (TRM 530-602)

• See Figure A-1 through Figure A-3 b Sample Codes:

AM = Atmospheric moisture PW= Public water ss = Shoreline sediment AP= Air particulate filter V= Vegetation SW= Surface water F = Fish S= Soil W= Well water CF= Charcoal Filter M= Milk c A control for well water d Distance from plant discharge (TRM 483.7) 2021 Sequoyah AREOR [25]

APPENDIX A Table A Sequoyah Environmental Dosimeter Locations Map Location Distance Onsite or Number* Station Sector (miles) Offsiteb 3 SSW-1C SSW 2.0 off 4 NE-1A NE 1.5 on site 5 NNE-1 NNE 1.8 on site 7 SW-2 SW 3.8 off 8 W-3 w 5.6 off 9 SSW-3 SSW 8.7 off 10 WSW-2A WSW 2.6 off 11 SW-3 SW 16.7 off 12 NNE-4 NNE 17.8 off 13 ESE-3 ESE 11.3 off 14 NW-3 NW 20.0 off 49 N-1 N 0.6 on site 50 N-2 N 2.1 off 51 N-3 N 5.2 off 52 N-4 N 10.0 off 53 NNE-2 NNE 5.3 off 55 NE-1 NE 2.4 off 56 NE-2 NE 4.1 off 57 ENE-1 ENE 0.2 on site 58 ENE-2 ENE 5.1 off 59 E-1 E 1.2 on site 60 E-2 E 5.2 off 62 ESE-1 ESE 1.2 on site 63 ESE-2 ESE 4.9 off 66 SE-1 SE 1.4 on site 67 SE-2 SE 1.9 on site 68 SE-4 SE 5.2 off 69 SSE-1 SSE 1.6 on site 70 SSE-2 SSE 4.6 off 71 S-1 s 1.5 on site 72 S-2 s 4.7 off 73 SSW-1 SSW 0.6 on site 74 SSW-2 SSW 4.0 off 75 SW-1 SW 0.7 on site 76 WSW-1 WSW 0.9 on site 77 WSW-2 WSW 2.5 off 78 WSW-3 WSW 5.7 off 79 WSW-4 WSW 7.8 off 81 W-1 w 0.6 on site 82 W-2 w 4.3 off 83 WNW-1 WNW 0.4 on site 2021 Sequoyah AREOR [26]

APPENDIX A Table A Sequoyah Environmental Dosimeter Locations (Continued)

Map Location Distance Onsite or Number Station Sector (miles) Offsite 84 WNW-2 WNW 5.3 Off 85 NW-1 NW 0.4 on site 86 NW-2 NW 5.2 off 87 NNW-1 NNW 0.6 on site 88 NNW-2 NNW 1.7 on site 89 NNW-3 NNW 5.3 off 90 SSW-1B SSW 1.5 on site

• See Figure A-1 through Figure A-3 b Dosimeters designated "onsite" are located 2 miles or less from the plant; "offsite" are located more than 2 miles from the plant 2021 Sequoyah AREOR [27]

APPENDIX A Figure A Radiological Environmental Sampling Locations Within 1 Mile of the Plant N 11 .25 78 . 75 E

10 1. 2 5 123 . 75 191.25 $ 168 . 7 5 Scale 0 Mile 1 2021 Sequoyah AREOR [28]

APPENDIX A Figure A Radiological Environmental Sampling Locations from 1 to 5 Miles from the Plant 348.75 N 11.25 191 .25 s 168.75 SCALE 0 1 2 MILES 2021 Sequoyah AREOR [29]

APPENDIX A Figure A Radiological Environmental Sampling Locations Greater Than 5 Miles from the Plant 191.25 168.75 0:,-=-~:,,==-~ 1

- 6SCALE1S .. . **2075 MILES 2021 Sequoyah AREOR [30]

APPENDIX B PROGRAM MODIFICATIONS 2021 Sequoyah AREOR [31]

APPENDIX B Radiological Environmental Monitoring Program Modifications In December 2021, location PM-9 was relocated. This location was used for air (particulate and iodine) and soil sampling. The PM-9 location was on private property, and an agreement for access to the location has expired. The new location, still in the WSW sector, is approximately 2 miles closer to the plant and will be recorded beginning in 2022.

2021 Sequoyah AREOR [32]

APPENDIX C PROGRAM DEVIATIONS 2021 Sequoyah AREOR [33]

APPENDIX C Program Deviations Media Location Date CR Issue Direct Radiation SSE-2 7/15/2021 1707624 TLD 25, Snowhill Road, was not located in the Q2 field, and pole and basket were damaged.

Pole and basket were replaced.

2021 Sequoyah AREOR [34]

APPENDIX D ANALYTICAL PROCEDURES 2021 Sequoyah AREOR [35]

APPENDIX D Analytical Procedures Analyses of environmental samples are performed by GEL Laboratories, LLC in Charleston, SC. Analysis of environmental dosimeters are performed by Landauer, Inc. in Glenwood, IL. Analysis procedures are based on accepted methods and summarized below.

The gross beta measurements are made with an automatic low background counting system . Normal counting times are 50 minutes. Water samples are prepared by evaporating 400 milliliter (ml) of samples to near dryness, transferring to a stainless steel planchet, and completing the evaporation process. Air particulate filters are counted directly in a shallow planchet.

Gamma analyses are performed in various counting geometries depending on the sample type and volume . All gamma counts are obtained with germanium type detectors interfaced with a high resolution gamma spectroscopy system. All samples requiring gamma analysis are analyzed in this manner.

The necessary efficiency values, weight-efficiency curves, and geometry tables are established and maintained on each detector and counting system. A series of daily and periodic quality control checks are performed to monitor counting instrumentation. System logbooks and control charts are used to document the results of the quality control checks.

The specific analysis of 1-131 in milk is performed by first isolating and purifying the iodine by radiochemical separation and then counting the final precipitate on a beta-gamma coincidence counting system. The normal count time is 480 minutes. Then the 1-131 is counted by gamma spectroscopy utilizing high resolution Ge detectors.

After a radiochemical separation, milk samples analyzed for Sr-89 and Sr-90 are counted on a low background beta counting system . The sample is counted a second time after a minimum ingrowth period of six days. From the two counts, the Sr-89 and Sr-90 concentrations can be determined.

Water samples are analyzed for tritium content by first distilling a portion of the sample and then counting by liquid scintillation. A commercially available scintillation cocktail is used.

The Landauer In light Environmental Dosimetry System is used for measuring direct radiation in the REMP.

Landauer has performed type testing of this system in accordance with ANSI N13.37-2014 standards.

2021 Sequoyah AREOR [36]

APPENDIX E LOWER LIMITS OF DETECTION 2021 Sequoyah AREOR [37]

APPENDIX E Lower Limits of Detection Many factors influence the Lower Limit of Detection (LLD) for a specific analysis method, including sample size, count time, counting efficiency, chemical processes, radioactive decay factors, and interfering isotopes encountered in the sample. Nominal LLD values for the environmental monitoring program are calculated based on system parameter values for each of the components as identified above, in accordance with the methodology prescribed in the ODCM . The current nominal LLD values achieved by the radioanalytical lab are listed in Table E-2 and Table E-3. For comparison, the maximum values for the lower limits of detection specified in the ODCM are given in Table E-4.

Table E Comparison of Program Lower Limits of Detection with the Regulatory Limits for Maximum Annual Average Effluent Concentration Released to Unrestricted Areas and Reporting Levels Concentrations in Water {12CiLLiter) Concentrations in Air {12CiLm 3) 10 CFR 20 10 CFR 20 Effluent Lower Effluent Lower Concentration Reporting Limit of Concentration Reporting Limit of Analysis Limita Levelb, c Detectiond Limita Levelb, c Detectiond H-3 1,000,000 20,000 270 100,000 Cr-51 500,000 45 30,000 0.02 Mn-54 30,000 1000 5 1,000 0.005 Fe-59 10,000 400 10 500 0.005 Co-58 20,000 1000 5 1,000 0.005 Co-60 3,000 300 5 50 0.005 Zn-65 5,000 300 10 400 0.005 Sr-89 8,000 1,000 Sr-90 500 6 Nb-95 30,000 400 5 2,000 0.0005 Zr-95 20,000 400 10 400 0.005 Ru-103 30,000 5 900 0.005 Ru-106 3,000 40 20 0.02 1-131 1,000 2 0.4 200 0.9 0.03 Cs-134 900 30 5 200 10 0.005 Cs-137 1,000 50 5 200 20 0.005 Ce-144 3,000 30 40 0.01 Ba-140 8,000 200 25 2,000 0.015 La-140 9,000 200 10 2,000 0.01

• Source: Table 2 of Appendix B to 10 CFR 20.1001-20.2401 b For those reporting levels and lower limits of detection that are blank, no value is given in the reference c Source: SQN Offsite Dose Calculation Manual, Table 2.3-2 d Source: Table E-2 and Table E-3 of this report 2021 Sequoyah AREOR [38]

APPENDIX E Table E Nominal LLD Values - Radiochemical Airborne Particulate or Wet Sediment Gases Water Milk Vegetation and Soil Analysis {12CiLm 3 ) il&lL!J il&lL!J {12CiLkg, wet) {12CiLkg, dry)

Gross beta 0.002 1.9 H-3 3.0 270 1-131 0.4 0.4 6.0 Sr-89 3.5 1.6 Sr-90 2.0 0.4 Table E Nominal LLD Values - Gamma Analysis Water Wet Sediment Food Airborne Charcoal and Vegetation and Soil Fish Products Particulate Filter Milk {12CiLkg, {12CiLkg, {12CiLkg, {12CiLkg, Analysis {12CiLm 3 } {12CiLm 3 } il&lL!J wet} Qill wet} wet}

Ce-141 0.005 0.02 10 35 0.10 0.07 20 Ce-144 0.01 0.07 30 115 0.20 0.15 60 Cr-51 0.02 0.15 45 200 0.35 0.30 95 1-131 0.005 0.03 10 60 0.25 0.20 20 Ru-103 0.005 0.02 5 25 0.03 0.03 25 Ru-106 0.02 0.12 40 190 0.20 0.15 90 Cs-134 0.005 0.02 5 30 0.03 0.03 10 Cs-137 0.005 0.02 5 25 0.03 0.03 10 Zr-95 0.005 0.03 10 45 0.05 0.05 45 Nb-95 0.005 0.02 5 30 0.04 0.25 10 Co-58 0.005 0.02 5 20 0.03 0.03 10 Mn-54 0.005 0.02 5 20 0.03 0.03 10 Zn-65 0.005 0.03 10 45 0.05 0.05 45 Co-60 0.005 0.02 5 20 0.03 0.03 10 K-40 0.04 0.30 100 400 0.75 0.40 250 Ba-140 0.015 0.07 25 130 0.30 0.30 50 La-140 0.01 0.04 10 50 0.20 0.20 25 Fe-59 0.005 0.04 10 40 0.05 0.08 25 Be-7 0.02 0.15 45 200 0.25 0.25 90 Pb-212 0.005 0.03 15 40 0.10 0.04 40 Pb-214 0.005 0.07 20 80 0.15 0.10 80 2021 Sequoyah AREOR [39]

APPENDIX E Table E Nominal LLD Values - Gamma Analysis (continued)

Water Wet Sediment Food Airborne Charcoal and Vegetation and Soil Fish Products Particulate Filter Milk (12CiLkg, (12CiLkg, (12CiLkg, (12CiLkg, Analysis (12CiLm 3 ) (12CiLm 3 ) 1I&lL!J wet) .9.IYl wet) wet)

Bi-214 0 .005 0 .05 20 55 0.15 0.10 40 Bi-212 0.02 0.20 so 250 0.45 0.25 130 Tl-208 0.002 0.02 10 30 0.06 0.03 30 Ra-224 0.75 Ra-226 0.15 Ac-228 0.01 0.07 20 70 0.25 0.10 so Pa-234m 800 4.0 Table E Maximum Values for Lower Limits of Detection (LLD)

Airborne Particulate or Fish Food Water Gases (12CiLkg, Milk Products Sediment Analysis 1I&lL!J (12CiLm 3) wet) 1I&lL!J (12CiLkg 1 wet} (12CiLkg, dry}

Gross beta 4 0.01 H-3 2000a Mn-54 15 130 Fe-59 30 260 Co-58, 60 15 130 Zn-65 30 260 Zr-95 30 Nb-95 15 1-131 lb 0.07 1 60 Cs-134 15 0.05 130 15 60 150 Cs-137 18 0.06 150 18 80 180 Ba-140 60 60 La-140 15 15 Notes

a. If no drinking water pathway exists, a value of 3000 pCi/L may be used

b. If no drinking water pathway exists, a value of 15 pCi/L may be used.

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APPENDIX F QUALITY ASSURANCE/ QUALITY CONTROL PROGRAM APPENDIX F Quality Assurance/ Quality Control Program A quality assurance program is employed by the offsite vendor laboratory to ensure that the environmental monitoring data are reliable. This program includes the use of written, approved procedures in performing the work, provisions for staff training and certification, internal self-assessments of program performance, audits by various external organizations, and a laboratory quality control program .

The quality control program employed by the radioanalytical laboratory is designed to ensure that the sampling and analysis process is working as intended . The program includes equipment checks and the analysis of quality control samples, along with routine field samples. Instrument quality control checks include background count rate and counts reproducibility. In addition to these two general checks, other quality control checks are performed on the variety of detectors used in the laboratory. The exact nature of these checks depends on the type of device and the method it uses to detect radiation or store the information obtained.

Quality control samples of a variety of types are used by the laboratory to verify the performance of different portions of the analytical process. These quality control samples include blanks, field duplicates, process duplicates, matrix spikes, laboratory control samples, and independent cross-checks.

Blanks are samples which contain no measurable radioactivity of the type being measured. Such samples are analyzed to determine whether there is any contamination or cross-contamination of equipment, reagents, processed samples, or interferences from isotopes other than the ones being measured.

Duplicate field samples are generated at random by the sample computer program which schedules the collection of the routine samples. For example, if the routine program calls for four milk samples every week, on a random basis each farm might provide an additional sample several times a year. These duplicate samples are analyzed along with other routine samples. They provide information about the variability of radioactive content in the various sample media. If enough sample is available for a particular analysis, the laboratory staff can split the sample taking two individual aliquots, known as process duplicates. Duplicate samples provide information about the variability of the entire sampling and analytical process.

Matrix spikes are field samples that have been spiked with known low levels of specific target isotopes.

Recovery of the known amount allow the analyst to determine if any interferences are exhibited from the field sample's matrix.

Laboratory control samples are another type of quality control sample. A known amount of radioactivity is added to a sample medium and processed along with the other QC and field samples in the analytical batch . Laboratory control samples provide the assurance that all aspects of the process have been successfully completed within the criteria established by Standard Operating Procedure.

Another category of quality control samples is cross-check samples. The laboratory procures single-blind performance evaluation samples from Eckert & Ziegler Analytics to verify the analysis of sample matrices processed at the laboratory. Samples are received on a quarterly basis. The laboratory's Third-Party Cross-Check Program provides environmental matrices encountered in a typical nuclear utility REMP.

Once performance evaluation samples have been prepared in accordance with the instructions from the performance evaluator provider, samples are managed and analyzed in the same manner as 2021 Sequoyah AREOR [42]

APPENDIX F environmental samples. These samples have a known amount of radioactivity added and are presented to the lab staff labeled as cross-check samples. The laboratory does not know the amount of radioactivity added to the sample. Such samples test the best performance of the laboratory by determining if the laboratory can find the "right answer." These samples provide information about the accuracy of the measurement process. Further information is available about the variability of the process if multiple analyses are requested on the same sample. Like matrix spikes or laboratory control samples, these samples can also be spiked with low levels of activity to test detection limits. The analysis results for internal cross-check samples met program performance goals for 2021.

The quality control data are routinely collected, examined and reported to laboratory supervisory personnel. They are checked for trends, problem areas, or other indications that a portion of the analytical process needs correction or improvement. The result is a measurement process that provides reliable and verifiable data and is sensitive enough to measure the presence of radioactivity far below the levels which could be harmful to humans.

Per the GEL 2021 Annual Environmental Quality Assurance (QA) Report (GEL, 2022), forty-five (45) radioisotopes associated with seven (7) matrix types (air filter, cartridge, water, milk, soil, liquid and vegetation) were analyzed under GEL's Performance Evaluation program in participation with ERA, Department of Energy Mixed Analyte Performance Evaluate Program (MAPEP), and Eckert & Ziegler Analytics. Matrix types were representative of client analyses performed during 2021. Of the four hundred thirty-three (433) total results, 96.51% (418 of 433) were found to be acceptable within the PT providers three sigma or other statistical criteria. For the Eckert & Ziegler Analytics Environmental Cross Check Program, GEL was provided ninety-one (91) individual environmental analyses. The accuracy of each result reported to Eckert & Ziegler Analytics, Inc. is measured by the ratio of GEL's result to the known value. All results fell within GEL's acceptance criteria (100% within acceptance) .

The radioanalytical lab performance in 2021 meets the criteria described in Reg. Guide 4.15 and ANSI/HPS N13.37-2014.

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APPENDIX G APPENDIX G LAND USE CENSUS 2021 Sequoyah AREOR [44]

APPENDIX G Land Use Census A land use census is conducted annually to identify the location of the nearest milk producing animal, the nearest residence, and the nearest garden of greater than 500 square feet producing fresh leafy vegetables in each of 16 meteorological sectors within 5 miles (8,047 meters) from the plant.

The land use census is conducted between April 1 and October 1 using appropriate techniques such as door-to-door survey, mail survey, telephone survey, aerial survey, or information from local agricultural authorities or other reliable sources.

The location of the nearest resident changed in one sector in 2021. The location of the nearest garden greater than 500 ft 2 was updated in two sectors.

Results of the 2021 Land Use Census did not identify the need for any changes to the sampling locations or sampling media as currently required by the SQN REMP.

Table G Updated Nearest Residence 2020 Nearest 2021 Nearest Resident Resident Sector {meters) {meters)

WNW 1331 624 Table G Updated Nearest Garden 2020 Nearest 2021 Nearest Garden Garden Sector {meters) {meters)

ESE 1861 1851 SSE 6190 2330 Table G Sequoyah Land Use Census Results Nearest Nearest Nearest Milk Meteorological Resident Garden Production Sector {meters) {meters) {meters)

N 1389 4329 NNE 2456 3770 NE 3400 6230 ENE 2127 5220 E 1732 5370 ESE 1693 1851 SE 1721 3406 SSE 2073 2330 2021 Sequoyah AREOR [45]

APPENDIX G Nearest Nearest Nearest Milk Meteorological Resident Garden Production Sector (meters) (meters) (meters) s 1764 4010 SSW 2129 4363 SW 2502 4920 WSW 1036 1152 w 982 3050 WNW 624 5363 NW 1316 1316 NNW 864 2502 2021 Sequoyah AREOR [46]

APPENDIX H DATA TABLES AND FIGURES APPENDIX H Table H Weekly Airborne Particulate Gross Beta All Indicator Location with Highest Annual Mean All Control Sample Lower Limit Non-routine Type and Number of Locations Locations Pathway of Detection Name, Distance and Reported Analysis Performed Mean (Count) Mean (Count)

(Measurement Unit) (LLD)* Mean (Range) Measurements Range Direction Range Air Filter 0.036 (416/416) 0.038 (52/52) 0.037 (208/208)

Inhalation Gross Beta 624 0.01 RM-2, 15.0 Mi. SWb 0 (0.001- 0.086) (0.019 - 0.084) (0.001- 0.086)

(pCi/m 3 )

NOTES

a. LLD is the a priori limit as prescribed by the ODCM.

b. The location with the highest annual mean is a control location.

Figure H-1 -Average Beta Activity in Air Filters Annual Average Beta Activity in Air Filters Sequoyah

("(')

E 0.2500

...._ 0.2000 0

0..

';: 0.1500

-~ 0.1000 u

<(

ca. 0.0500 a.,

tl.O

~ 0.0000 a.,

1970 1980 1990 2000 2010 2020

~

-+- Indicator - control - - Preoperational Average 2021 Sequoyah AREOR [48]

APPENDIX H Table H Weekly Airborne 1-131 Radioactivity All Indicator Location with Highest Annual Mean All Control Sample Lower Limit Non-routine Type and Number of Locations Locations Pathway

• of Detection Name, Distance and Reported Analysis Performed Mean (Count) Mean (Count)

(Measurement Unit) (LLD) Mean (Range) Measurements Range Direction Range Activated Charcoal Inhalation 1-131 624 0.07 < LLD* (0/416) < LLD < LLD < LLD (0/208) 0 (pCi/m 3 )

NOTES

a. The term "< LLD" as used means that results had no identified activity above the minimum detectable.

Table H Monthly Airborne Composite Particulate Gamma Radioactivity All Indicator Location with Highest Annual Mean All Control Sample Lower Limit Non-routine Type and Number of Locations Locations Pathway of Detection Reported Analysis Performed Mean (Count) Name, Distance and Mean (Count)

(Measurement Unit) (LLD) Mean (Range) Measurements Range Direction Range Air Filter Gamma Inhalation 156 Various < LLD* (0/104) < LLD < LLD < LLD (0/52) 0 Isotopic *

(pCi/m 3 )

NOTES

a. Natural occurring radionuclides were observed in monthly composite air samples.

b. See Table E-1 through Table E-4 for the required and nominal LLDs for individual radionuclides via gamma isotopic analysis.

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APPENDIX H Table H Monthly Vegetation Gamma Radioactivity All Indicator Location with Highest Annual Mean All Control Sample Lower Limit Non-routine Type and Number of Locations Locations Pathway* of Detection Name, Distance and Reported Analysis Performed Mean (Count) Mean (Count)

(Measurement Unit) (LLD) Mean (Range) Measurements Range Direction Range Vegetation Gamma Ingestion 26 Various N/A < LLD < LLD < LLD (0/26) 0 Isotopic *

(pCi/m 3 )

NOTES

a. Natural occurring radionuclides were observed in vegetation samples.

Table H Annual Soil Radioactivity All Indicator Location with Highest Annual Mean All Control Sample Lower Limit Non-routine Type and Number of Locations Locations Pathway of Detection Reported Analysis Performed Mean (Count) Name, Distance and Mean (Count)

(Measurement Unit) (LLD) Mean (Range) Measurements Range Direction Range Gamma 12 Various < LLD* (0/8) < LLD < LLD < LLD (0/4) 0 Isotopic

• Soil 238 (4/8) 409 (1/1) 143 (2/4)

Cs-137b 12 180 PM-8, 8.7 Mi. SSW 0 Direct Radiation 115 -409 409-409 141- 145 (pCi/g) 115 (1/1) 115 (1/1)

Sr-89 12 N/A LM-3, 2.0 Mi. SSW < LLD (0/4) 0 115- 115 115- 115 Sr-90 12 N/A < LLD (0/8) < LLD < LLD < LLD (0/4) 0 NOTES

a. Natural occurring radionuclides were observed in soil samples.

b. Cs-137 is the only non-natural radionuclide positively identified as part of the gamma isotopic analysis 2021 Sequoyah AREOR [SO]

APPENDIX H Table H Annual Local Crop Radioactivity All Indicator Location with Highest Annual Mean All Control Lower Limit Non-routine Sample Pathway Type and Number of Locations Locations of Detection Name, Distance and Reported (Measurement Unit) Analysis Performed Mean (Count) Mean (Count)

(LLD} Mean (Range) Measurements Range Direction Range Food Products Gamma Ingestion 12 Various b < LLD (0/6) < LLD < LLD < LLD (0/6) 0 Isotopic *

(pCi/g)

NOTES

a. Natural occurring radionuclides were observed in local crop samples.

b. See Table E-1 through Table E-4 for the required and nominal LLD s for individual radionuclides via gamma isotopic analysis.

Table H Monthly Surface Water Radioactivity All Indicator Location with Highest Annual Mean All Control Sample Lower Limit Non-routine Type and Number of Locations Locations Pathway of Detection Name, Distance and Reported Analysis Performed Mean (Count) Mean (Count)

(Measurement Unit) (LLD} Mean (Range) Measurements Range Direction Range Gamma Surface Water 28 Various < LLD (0/15) < LLD < LLD < LLD (0/13) 0 Isotopic

• Direct Exposure 494 (6/17) 494 (6/17) 524 (3/17)

(pCi/L) Tritiumb 21 2000 TRM 503 .8 c 0 281- 773 281- 773 482 - 551 NOTES

a. Natural occurring radionuclides were observed in surface water samples .

b. SQN ODCM requires quarterly tritium samples on surface water samples

c. The location with the highest annual mean is a control location .

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APPENDIX H Table H Monthly Public Drinking Water Radioactivity All Indicator Location with Highest Annual Mean All Control Sample Lower Limit Non-routine Type and Number of Locations Locations Pathway of Detection Name, Distance and Reported Analysis Performed Mean (Count) Mean (Count)

(Measurement Unit) (LLD) Mean (Range) Measurements Range Direction Range 13.4 (4/39) 28.1 (1/13 24.1 (1/14)

Gross Beta 53 4.0 TRM 465 .3 0 2.6-28.1 28.1-28.1 24.1-24.1 Drinking Water Gamma Ingestion 52 Various < LLD* (0/39) N/A N/A < LLD (0/14) 0 Isotopic a (pCi/L) 1400 (1/12) 1400 (1/4) 494 (6/16)

Tritium 28 2000 TRM 465 .3 0 1400-1400 1400-1400 281- 773 NOTES

a. Natural occurring radionuclides were observed in drinking water samples.

Table H Quarterly Well (Ground) Water Radioactivity All Indicator Location with Highest Annual Mean All Control Sample Lower Limit Non-routine Type and Number of Locations Locations Pathway of Detection Name, Distance and Reported Analysis Performed Mean (Count) Mean (Count)

(Measurement Unit) (LLD) Mean (Range) Measurements Range Direction Range 8.2 (3/4) 8.2 (3/4)

Gross Beta 11 4.0 < LLD (0/7) Farm HW, 1.2 Mi., NWb 0 Ground Water 4.55-10.5 4.55-10.5 Ingestion Gamma 11 Various < LLD* (0/7) < LLD < LLD < LLD (0/4) 0 (pCi/L) Isotopic a Tritium 11 2000 < LLD (0/7) < LLD < LLD < LLD (0/4) 0 NOTES

a. Natural occurring radionuclides were observed in ground water samples.

b. The location with the highest annual mean is a control location 2021 Sequoyah AREOR [52]

APPENDIX H Table H Semi-Annual Fish Radioactivity All Indicator Location with Highest Annual Mean All Control Sample Lower Limit Non-routine Type and Number of Locations Locations Pathway of Detection Name, Distance and Reported Analysis Performed Mean (Count) Mean (Count)

(Measurement Unit) (LLD) Mean (Range) Measurements Range Direction Range Game Fish - Large Mouth Bass Gamma 4 Various < LLD* (0/2) < LLD < LLD < LLD (0/2) 0 Ingestion Isotopic *

(pCi/kg)

Commercial Fish -

Channel Catfish Gamma 6 Various < LLD (0/4) < LLD < LLD < LLD (0/2) 0 Ingestion Isotopic (pCi/kg)

NOTES

a. Natural occurring radionuclides were observed in fish samples.

Table H Semi-Annual Shoreline Sediment Radioactivity All Indicator Location with Highest Annual Mean All Control Sample Lower Limit Non-routine Type and Number of Locations Locations Pathway of Detection Name, Distance and Reported Analysis Performed Mean (Count) Mean (Count)

(Measurement Unit) (LLD) Mean (Range) Measurements Range Direction Range Shoreline Sediment Gamma 34.7 (1/2)

Direct Radiation 6 Various < LLD* (0/4) TRM 479.0 < LLD (0/2) 0 Isotopic

• 34.7- 34.7 (pCi/kg)

NOTES

a. Natural occurring radionuclides were observed in shoreline sediment samples.

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APPENDIX I ERRATA TO PREVIOUS ANNUAL ENVIRONMENTAL OPERATING REPORTS

APPENDIX I Errata to Previous AREORs There are no identified errors in previous AREORs.

2021 Sequoyah AREOR [55]