ML24120A040

Annual Radioactive Effluent Release Report for 2023

ML24120A040
Person / Time
Site:	Oyster Creek
Issue date:	04/29/2024
From:	Noval W Holtec Decommissioning International
To:	Office of Nuclear Material Safety and Safeguards, Document Control Desk, Office of Nuclear Reactor Regulation
References
HDI-OC-24-020
Download: ML24120A040 (1)

Text

Krishna P. Singh Technology Campus, 1 Holtec Blvd., Camden, NJ 08104 Telephone (856) 797-0900 Fax (856) 797-0909 HDI-OC-24-020 10 CFR 50.36a(a)(2) 10 CFR 72.44 (d)(3)

April 29, 2024 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 Oyster Creek Nuclear Generating Station Renewed Facility Operating License No. DPR-16 NRC Docket No. 50-219 and 72-15

Subject:

Annual Radioactive Effluent Release Report for 2023 Enclosed with this cover letter is the Annual Radioactive Effluent Release Report for the period January 1 to December 31, 2023. This report includes the Oyster Creek Nuclear Generating Station Independent Spent Fuel Storage Facility.

There are no regulatory commitments in this letter.

Should you have any question or require further information, please contact Kevin Wolf, Radiation Protection and Chemistry Manager, at (609) 971-4051.

Respectfully, William Noval Director of Regulatory Affairs Holtec Decommissioning International, LLC

Enclosures:

1) 2023 Annual Radioactive Effluent Release Report cc:

USNRC Regional Administrator, Region I USNRC Project Manager, NMSS - Oyster Creek Nuclear Generating Station USNRC Region I, Lead Inspector - Oyster Creek Nuclear Generating Station Assistant Commissioner, Air Quality, Energy and Sustainability, NJ DEP Principal Engineer, American Nuclear Insurers Assistant Director Radiation Protection Element, NJ Bureau of Nuclear Engineering Digitally signed by William Noval DN: cn=William Noval, c=US, o=HDI, ou=Regulatory Affairs, email=w.noval@holtec.com Date: 2024.04.29 07:51:30 -04'00' William Noval

to HDI-OC-24-020 Annual Radioactive Effluent Release Report (ARERR) 2023 Oyster Creek Nuclear Station

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 2 ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT January 1, 2023, through December 31, 2023 HOLTEC DECOMMISSIONING INTERNATIONAL OYSTER CREEK NUCLEAR STATION DOCKET NO. 50-219 (Oyster Creek Nuclear Station)

DOCKET NO. 72-15 (Independent Spent Fuel Storage Facility)

Submitted to The United States Nuclear Regulatory Commission Pursuant to Renewed Facility Operating License DPR-16

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 3 TABLE OF CONTENTS I.

EXECUTIVE

SUMMARY

......................................................................................................... 4

1.

Understanding Radiation..................................................................................................... 6

2.

Sources of Radiation......................................................................................................... 10

3.

Exposure Pathways........................................................................................................... 12

4.

Radiation Risk................................................................................................................... 13

5.

Annual Reports.................................................................................................................. 15

6.

Introduction........................................................................................................................ 16 II.

SUPPLEMENTAL INFORMATION (MAIN BODY OF REG GUIDE 1.21 REPORT)............... 18

1.

Abnormal Releases and Abnormal Discharges (e.g., leaks and spills)............................... 18

2.

Non routine, Planned Discharges...................................................................................... 18

3.

Radioactive Waste Treatment System Changes................................................................ 18

4.

Annual Land-Use Census Changes................................................................................... 18

5.

Effluent Monitor Instrument Inoperability............................................................................ 18

6.

Offsite Dose Calculation Manual Changes......................................................................... 18

7.

Process Control Program Changes................................................................................... 18

8.

Errata/Corrections to Previous ARERRs............................................................................ 18

9.

Other................................................................................................................................. 18 III.

Appendices........................................................................................................................ 19

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 4 I.

EXECUTIVE

SUMMARY

The 2023 Oyster Creek Nuclear Station Annual Radioactive Effluent Release Report (ARERR) is attached. The format of this report was modified for the 2019 report following the adoption of Regulatory Guide 1.21, Revision 2, reporting format and updated reporting tables. There have also been some simplifications to the reporting which is the result of the new reporting format and physical changes to the station (system, structure and source term reductions) as decommissioning was initiated in 2019, including transfer of the station and decommissioning license from Exelon Nuclear to Holtec Decommissioning International, LLC (HDI).

Report Format Changes Radioactive waste and effluent tables used are from the latest revision to Regulatory Guide 1.21, revision 2, Measuring, Evaluating, and Reporting Radioactive Material in Liquid and Gaseous Effluents and Solid Waste Meteorological Data are not reported here, per revision 2 to Regulatory Guide 1.21. This information is readily available at the station for review upon request.

Effluents are strictly monitored to ensure that radioactivity released to the environment is as low as reasonably achievable (ALARA) and does not exceed regulatory limits. Effluent control includes the operation of monitoring systems, in-plant and environmental sampling and analyses programs, quality assurance programs for the effluent and environmental programs, and procedures covering all aspects of effluent and environmental monitoring.

Both radiological environmental and effluent monitoring indicate that the operation of Oyster Creek Nuclear Station (formerly Oyster Creek Nuclear Generating Station - OCGS) does not result in significant radiation exposure to the people or the environment surrounding OCGS and is well below the applicable levels set by the Nuclear Regulatory Commission (NRC) and the Environmental Protection Agency (EPA). This continues to be true now that Oyster Creek has entered its decommissioning phase.

On July 1st, 2019, ownership of the Oyster Creek Nuclear Station and transfer of its license, (permanently shut down effective September 26, 2018), was transferred from Exelon Nuclear to Holtec Decommissioning International. Exelon had determined that transitioning operational nuclear plants to decommissioning nuclear plants targeted for permanent shutdown was not aligned with its core objectives and actively sought buyers who would assume ownership and complete decommissioning and license termination for the Oyster Creek Nuclear Station. With permanent shutdown and transfer of the spent fuel from the reactor vessel to the Spent Fuel Pool (all fission reactions would be terminated at this point), certain elements of the effluent and environmental programs would change over time. One of these changes was the emergent need to process and dispense of the water inventory accumulated in plant systems. To that end, on-site processing (cleaning) of plant water for overboard discharges was re-introduced to the site in January 2019 with revision 9 to the Off-Site Dose Calculation Manual (ODCM).

With revision 9 to the ODCM and the restoration of liquid discharges, the site formally re-instituted processing, treating and permitted discharging of processed wastewater from plant systems to the 30 Header Combined Wastewater Outfall (DSN-004A). Levels of radioactivity in this water were detectable, but at low concentrations that were a small fraction of the federal limits. The off-site

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 5 dose impact from these liquid effluent discharges is summarized in this report and was found to be a small fraction of the federal dose limits. Additional changes included the termination of gaseous release from the Turbine Building, and removal of these ground level release points and pathways from the ODCM in January of 2019.

Tritium identified in groundwater monitoring wells was remediated by installing a remediation well (Well 73) in the effective center of the affected wells and drawing that tritiated water out and pumping it to the condenser intake structure where it was subsequently discharged to the main condenser outfall. At that outfall, the water was sampled and analyzed and found to be below the ODCM lower limit of detection (<LLD). This approach was utilized in lieu of natural attenuation of low levels of tritium in groundwater for two reasons: one was to accomplish remediation on a more accelerated timetable, and the other was to ensure that the water removed was channeled through a process that permitted tracking and accounting for potential off-site impact to a member of the public.

Exelon and the State of New Jersey Department of Environmental Protection (NJDEP) agreed to this approach, which Holtec continued until remediation was determined complete in the fourth quarter of 2019 and the project was terminated as a continuous discharge. ODCM revision 10 permits restoration of this process as batch or continuous releases if surrounding well sample results indicate marked increases in tritium concentrations above detection limits.

Well 73 was initially installed and put into service in 2010 to address low levels of tritium identified in groundwater. Well 73 and supporting equipment and piping were installed to pump groundwater to the intake structure at the inlet of the main circulating water pumps. Provisions were established for both batch and continuous releases of groundwater. When tritium was detectable, the concentration was quantified and resulting off-site doses (which were negligible) were calculated and reported in the Annual Radioactive Effluent Release Reports (ARERR) issued each year.

Well 73 had contained low levels of tritium at one point, but no radioactivity was detectable in 2019 as levels were below the ODCM Lower Limit of Detection (LLD). There were no gamma emitters or hard to detect (HTD) radionuclides identified in 2019 from remediation of Well 73. Nearby wells (monitored monthly with no detectable activity), which feed remediation Well 73 also showed no detectable activity for gamma emitters or HTD radionuclides using state of the art analytical equipment on-site and at vendor labs. Since the pumping from Well 73 has ceased, the resulting small dose from tritium, when detectable in the well also ended.

There were no abnormal gaseous or liquid releases in 2023.

The maximum calculated organ dose (Child Gi-LLI) from tritium and particulates to any individual due to gaseous effluents was 4.53E-07 mrem, which was 3.02E-06 percent of the annual limit of 1.50E+01 mrem. The organ dose from gaseous effluents was primarily due to tritium (>99.99% of total gaseous dose), as there were particulate isotopes detected in gaseous effluents in only one month during 2023. With permanent power cessation in September 2018, no C-14 was produced in 2023, and neither noble gases or iodine were produced or detected in any gaseous effluents.

There was no maximum calculated gamma air dose in the UNRESTRICTED AREA due to a lack of noble gas production or presence in gaseous effluents. For comparison, the background radiation dose averages approximately 620 mrem per year to the average person in the United States; the

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 6 40 CFR 190 dose limit is 25 mrem per year to a member of the public from all uranium cycle sources.

The Independent Spent Fuel Storage Installation (ISFSI) is a facility storing spent fuel canisters (containing spent nuclear fuel) that are immersed in a blanket of inert gas prior to being welded shut and then inserted into heavy concrete and steel rebar over packs for shielding and canister protection. In addition, four (4) casks containing radioactive components with concentrations in excess of certain values that are not suitable for near-surface transport and disposal are similarly prepared and stored. As these are sealed containers, no radioactive effluents or material is released from these containers. Based on off-site (at the controlled area boundary along US Route

9) Optically Stimulated Luminescence Dosimeter (OSLD) readings and accounting for occupancy, dose to a member of the public due to direct radiation from the ISFSI was less than 1 mrem in 2023.

The location used to assign the direct dose component for the 40 CFR 190 dose is assigned to warehouse workers in the warehouse located at the back site; beyond the site protected area boundary and staffed by members of the public. The occupancy factor for this location assumes a 40-hour work week and some attenuation from the warehouse building structure using guidance provided in Reg Guide 1.109. This location presents the highest direct dose to a member of the public and is summarized in Table A-5.

On site meteorology was discontinued at the end of 2021 and gaseous effluent dose calculations are calculated using 10-year average meteorology, as allowed by the ODCM.

BACKGROUND The nuclear power industry uses terms and concepts that may be unfamiliar to all readers of this report. This section of the report is intended to help the reader better understand some of these terms and concepts. In this section, we will discuss radiation and exposure pathways. This section is intended only to give a basic understanding of these subjects to hopefully allow the reader to better understand the data provided within the report.

Every nuclear power station is required to submit two reports annually, the Annual Radioactive Effluents Release Report (ARERR) and the Annual Radiological Environmental Operating Report (AREOR). The following information is provided in both reports for Oyster Creek Nuclear Station.

1. Understanding Radiation Radiation is simply defined as the process of emitting radiant energy in the form of waves or particles. Radiation can be categorized as ionizing or non-ionizing radiation. If the radiation has enough energy to displace electrons from an atom it is termed ionizing radiation. Typically, you will see a warning sign where there is a potential to be exposed to man-made ionizing radiation. These signs normally have the trefoil symbol on a yellow background.

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 7 Example Radiological warning signs People do not always recognize non-ionizing radiation as a form of radiation, such as light, heat given off from a stove, radio waves and microwaves. In our report we focus on the ionizing radiation that is produced at a nuclear power plant though it is important to note that ionizing radiation comes from many sources. In fact, the amount of ionizing radiation an average person is exposed to due to operation of a nuclear power plant is a very small fraction of the total ionizing radiation they will be exposed to in their lifetime and will be discussed later.

From this point forward this report will only be discussing ionizing radiation but will just use the term radiation.

Since this report discusses radiation in different forms and different pathways we first need to understand where the radiation comes from that we report. Radiation comes from atoms. So, what are atoms and how does radiation come from atoms?

You may have seen a Periodic Table of the Elements:

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 8 This table lists all the elements found on earth. An atom is the smallest part of an element that maintains the characteristics of that element. An atom is made up of three parts, protons, neutrons, and electrons.

The number of protons in an atom determines the element. A hydrogen atom will always have one proton while an oxygen atom will always have eight protons. The protons are clustered with the neutrons at the center of the atom and this is called the nucleus. Orbiting around the nucleus are the relatively small electrons. Neutrons do not have an electrical charge; protons have a positive charge while electrons have a negative charge. In an electrically neutral atom, the negative and positive charges are balanced. Atoms of the same element that have a different number of neutrons in their nucleus are called isotopes.

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 9 Isotopes all have the same chemical properties, and many isotopes are nonradioactive or stable while other isotopes may be unstable and are radioactive. Radioactive isotopes can be called a radionuclide, a radioisotope or simply called a radioactive atom. A radionuclide contains an excess amount of energy in the nucleus usually due to a deficit or excess of neutrons in the nucleus.

There are two basic ways radionuclides are produced at a nuclear power plant. The first way is a direct result of the fission process and the radionuclides created through this process are termed fission products. Fission occurs when a very large atom, such as Uranium-235 (U-235) and Plutonium-239 (Pu-239) absorbs a neutron into its nucleus making the atom unstable. In this instance the atom can split into smaller atoms. This splitting of the atom is called fission. When fission occurs, there is also a large amount of energy released from the atom in the form of heat which is what is used to produce the steam that will spin the turbines to produce electricity at a nuclear power plant.

The second way a radionuclide is produced at a nuclear power plant is through a process called activation and the radionuclides produced in this method are termed activation products. Water passes through the core where the fission process is occurring. This water is used to both produce the steam to turn the turbines and to cool the reactor. Though the water passing through the core is very pure water, there is always some other material within the water. This material typically comes from the material used in the plants construction, such as iron, manganese, or chromium from steel piping. As the water passes through the core, the material is exposed to the fission process and the radiation within the core can react with the material causing it to become unstable, creating a radionuclide. The atoms in the water itself can become activated and create radionuclides.

Over time, radioactive atoms will reach a stable state and no longer be radioactive. To do this they must release the excess energy. The release of excess energy can be in different forms and is called radioactive decay and the energy released is called radiation. The time it takes for a radionuclide to become stable is measured in the unit called half-life. A half-life is the amount of time it takes for half of the original radioactivity to decay. Each radionuclide has a specific half-life.

Some half-lives can be very long and are measured in years while others may be very short and are measured in seconds.

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 10 In this report you will see radionuclides listed such as Potassium-40 (K-40) and Cobalt-60 (Co-60).

The letter(s) represents the element, and the number represents the specific isotope of that element and is the number of neutrons and protons in the nucleus of that radionuclide. You may hear the term naturally occurring radioactive material (NORM) which refers to radionuclides that naturally occur in nature such as K-40. There are man-made radionuclides such as Co-60 that we are concerned with since these man-made radionuclides result as a by-product when generating electricity at a nuclear power plant. There are other ways man-made radionuclides are produced, such as detonating nuclear weapons, and this is important to note since nuclear weapons testing deposited these man-made radionuclides into the environment, and some are still present today.

There is a discussion in the AREOR for the radionuclides Cesium-137, Strontium-89 and Strontium-90 (Cs-137, Sr-89 and Sr-90). The reason we only see some of the radionuclides today is due to differing rates of radioactive decay, some of the radionuclides released into the environment had relatively short half-lives and all the atoms have decayed to a stable state while other radionuclides have relatively long half-lives and will be measurable in the environment for years to come.

2. Sources of Radiation People are exposed to radiation every day of their lives and have been since the dawn of mankind.

Some of this radiation is naturally occurring while some is man-made. There are many factors that will determine the amount of radiation an individual will be exposed to such as where you live, medical treatments, etc. Below are examples of some of the typical sources of radiation an individual is exposed to in a year.

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 11 Adapted with permission of the National Council on Radiation Protection and Measurements, http://NCRPonline.org As you can see from the graph, the largest natural source of radiation is due to Radon. That is because essentially all air contains Radon. Cosmic and Internal make up the next largest natural sources of radiation. Cosmic radiation comes from the sun and stars and there are multiple factors which can impact the amount of cosmic radiation you are exposed to such as the elevation at which you live and the amount of air travel you take a year. The internal natural source of radiation mainly comes from two naturally occurring sources. Technically, all organic material is slightly radioactive due to Carbon-14 (C-14), including humans and the food we eat. C-14 makes up a percentage of the carbon in all organic material. Another contributor to the internal natural source is K-40 (Potassium-40). Potassium is present in many of the foods we eat, such as brazil nuts, bananas, carrots, and red meat. The smallest natural source listed is terrestrial. Soil and rocks contain radioactive materials such as Radium and Uranium. The amount of terrestrial radiation you are exposed to depends on where you live. The map below shows terrestrial exposure levels across the United States. The radiation released from nuclear power plants is included in the Industrial and Occupational slice and is listed as <0.1%.

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 12

3. Exposure Pathways Radiological exposure pathways define the methods by which people may become exposed to radioactive material. The major pathways of concern are those which could cause the highest calculated radiation dose. These projected pathways are determined from the type and amount of radioactive material released into the environment and how the environment is used. The way radioactive material is transported in the environment includes consideration of physical factors, such as the hydrological (water) and meteorological (weather) characteristics of the area. An annual average of the water flow, wind speed, and wind direction are used to evaluate how the radionuclides will be distributed in an area for gaseous or liquid releases. An important factor in evaluating the exposure pathways is the use of the environment. Many factors are considered such as dietary intake of residents, recreational use of the area, and the locations of homes and farms in the area.

The external and internal exposure pathways considered are shown in the picture below. The release of radioactive gaseous effluents involves pathways such as external whole-body exposure, deposition of radioactive material on plants, deposition on soil, inhalation by animals destined for human consumption, and inhalation by humans. The release of radioactive material in liquid effluents involves pathways such as drinking water, fish, and direct exposure from the water at the shoreline while swimming.

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 13 Although radionuclides can reach humans by many different pathways, some result in more dose than others. The critical pathway is the exposure route that will provide, for a specific radionuclide, the greatest dose to a population, or to a specific group of the population called the critical group.

The critical group may vary depending on the radionuclides involved, the age and diet of the group, or other cultural factors. The dose may be delivered to the whole body or to a specific organ. The organ receiving the greatest fraction of the dose is called the critical organ.

This simple diagram demonstrates some potential exposure pathways from Oyster Creek Nuclear Station.

4. Radiation Risk U.S. radiation protection standards are based on the premise that any radiation exposure carries some risk. There is a risk whether the radiation exposure is due to man-made sources or natural sources. There have been many studies performed trying to determine the level of risk. The following graph is an example of one study that tries to relate risk from many different factors. This graph represents risk as Days of Lost Life Expectancy. All the categories are averaged over the entire population except Male Smokers, Female Smokers and individuals that are overweight.

Those risks are only for people that fall into those categories. The category for Nuclear Power is a government estimate based on all radioactivity releases from nuclear power, including accidents and wastes.

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 14 Adapted from the article by Bernard L. Cohen, Ph.D. in the Journal of American Physicians and Surgeons Volume 8 Number 2 Summer 2003.

The full article can be found at http://www.jpands.org/vol8no2/cohen.pdf

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 15

5. Annual Reports All nuclear power plants are required to perform sampling of both the potential release paths from the plant and the potential exposure pathways in the environment. The results of this sampling are required to be reported annually to the Nuclear Regulatory Commission (NRC) and made available to the public. There are two reports generated annually, the Annual Radioactive Effluents Release Report (ARERR) and the Annual Radiological Environmental Operating Report (AREOR). The ARERR summarizes all the radioactive effluents released from the plant and quantifies the doses to the public from these effluents. The AREOR summarizes the results of the samples obtained in the environment looking at all the potential exposure pathways by sampling different media such as air, vegetation, direct radiation, etc. These two reports are related in that the results should be aligned. The AREOR should validate that the effluent program is accurate. The ARERR and AREOR together ensure Nuclear Power Plants are operating in a manner that adequately protects the public.

Measurement of radioactivity, exposure, and dose equivalent use different quantitative terms.

Together, they are used to properly capture both the amount of radiation and its effects on humans.

Radioactivity refers to the amount of ionizing radiation released by a material. The units of measure for radioactivity used within the AREOR and ARERR are the curie (Ci). Small fractions of the Ci often have a prefix, such as microcurie (Ci) that means 1/1,000,000 or picocurie (pCi) which means 1/1,000,000,000,000. That means there are 1,000,000 Ci or 1,000,000,000,000 pCi in one Ci.

Exposure describes the amount of radiation traveling through the air. The units of measure for exposure used within the AREOR and ARERR are the roentgen (R).

Traditionally direct radiation monitors placed around the site are measured in milliroentgen (mR), 1/1,000 of one R. That means there are 1,000 mR in one R.

Absorbed dose describes the amount of radiation absorbed by an object or person. The units of measure for absorbed dose used within the AREOR and ARERR are the rad.

Noble gas air doses, when reported by the site are measured in milliard (mrad), 1/1,000 of one rad. Due to the cessation of operation, the radioisotopes that would produce this radiation have decayed away and are no longer present at the site.

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

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 16 Typically releases from nuclear power plants are so low that the samples taken in the environment are below the detection levels required to be met by all nuclear power plants. There are some radionuclides identified in the environment during the routine sampling, but this is typically background radiation from nuclear weapons testing and events such as Chernobyl or Fukushima and these radionuclides are discussed in the AREOR.

Each report lists the types of samples that are collected, and the analyses performed. Different types of media may be used at one sample location looking for specific radionuclides. For example, at our gaseous effluent release points we use different media to collect samples for particulates and tritium. There are also examples where a sample collected on one media is analyzed differently depending on the radionuclide for which the sample is being analyzed.

These annual reports, and much more information related to nuclear power, are available on the NRC website at www.nrc.gov.

6. Introduction In accordance with the reporting requirements of Decommissioning Safety Analysis Report Appendix B.2.1.a, applicable during the reporting period, this report summarizes the effluent release data for OCGS for the period January 1, 2023 through December 31, 2023. This submittal complies with the format described in Regulatory Guide 1.21, "Measuring, Evaluating and Reporting Radioactivity in Solid Wastes and Releases of Radioactive Materials in Liquid and Gaseous Effluents from Light-Water-Cooled Nuclear Power Plants." Revision 2, June 2009.

All vendor results were received and included in the report calculations. Therefore, the 2023 report is complete.

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 17 Regulatory Limits:

Limit Units Receptor ODCM and 10 CFR 50, Appendix I Design Objective Limits

1. Tritium, Particulates with Half Life > 8 days:

a.

< 1500 mrem/yr Any Organ ODCM Control 3.11.2.1

b.

< 7.5 mrem/qtr Any Organ Quarterly dose limits ODCM Control 3.11.2.3

c.

< 15 mrem/yr Any Organ Yearly dose limits ODCM Control 3.11.2.3

2. Liquid Effluents:

a.

Concentration 10 CFR 20, Appendix B, Table 2 Column 2 ODCM Control 3.11.1.1

b.

< 1.5 mrem/qtr Total Body Quarterly dose limits

< 5 mrem/qtr Any Organ ODCM Control 3.11.1.2

c.

< 3 mrem/yr Total Body Yearly dose limits

< 10 mrem/yr Any Organ ODCM Control 3.11.1.2

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 18 II. SUPPLEMENTAL INFORMATION (MAIN BODY OF REG GUIDE 1.21 REPORT)

Oyster Creek Nuclear Station, Holtec Decommissioning International, LLC

1. Abnormal Releases and Abnormal Discharges (e.g., leaks and spills)

There were no Abnormal Releases or Abnormal Discharges (e.g., spills or leaks of radioactive material) during the decommissioning of the Oyster Creek Nuclear Station in 2023.

2. Non routine, Planned Discharges There were no non-routine, planned radioactive discharges (e.g., pumping of leaks and spills for remediation, results of ground water monitoring to quantify effluent releases to the offsite environment) for remediation resulting in releases off-site. Therefore, there was no off-site impact.

3. Radioactive Waste Treatment System Changes There were no physical changes to the Wastewater Treatment System or Waste Processing in 2023 at Oyster Creek.

4. Annual Land-Use Census Changes The Land Use Census was not required to be completed for the 2023 annual report in the same detail as previous reports. ODCM revision 13, which was released in 2022 removed the sampling of garden vegetables from the REMP and removed the requirement for a garden census. Monitoring of the nearest residence in each sector is performed by site staff.

5. Effluent Monitor Instrument Inoperability There were no Oyster Creek Station process radiation monitors out of service for more than 30 days in 2023.

6. Offsite Dose Calculation Manual Changes There were no revisions of the Offsite Dose Calculation Manual in 2023.

7. Process Control Program Changes There were no changes to the process control program in 2023.

8. Errata/Corrections to Previous ARERRs There are no Errata/corrections to previous ARERRs.

9. Other Other supplemental information are narrative descriptions of other information that is provided to the U.S. Nuclear Regulatory Commission, e.g., the ARERR for ISFSIs.

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 19

a. The meteorological tower was decommissioned in December 2021. Gaseous dose was calculated using Simplified Environmental Effluent Dosimetry System (SEEDS) until the end of 2021 when the on-site meteorological tower was decommissioned. Revision 10 of the Offsite Dose Calculation Manual (ODCM) established that 10-year average meteorological data will be used in decommissioning gaseous dose calculations at Oyster Creek. SEEDS is not capable of using average data to calculate dose, but it can calculate 10-year average /Q values that can be used to generate dose estimates. The methodology for calculating gaseous dose using average meteorology was developed and Radiation Protection Calculation and Position Paper OC-2022-03 Change in Method for Oyster Creek Gaseous Effluent Offsite Dose Calculation was approved to identify the new calculational method.

b. The ISFSI facility is located within the Oyster Creek Station Site and Controlled Area Boundaries. The termination of power operations has reduced the ambient dose rates on-site increasing the relative significance of the contributions from the ISFSI pad for direct radiation. The spent fuel has been moved out of the Reactor Building and is now stored on the ISFSI. Dose from the spent fuel reached a maximum when the pad was fully loaded; direct dose monitoring of the ISFSI has demonstrated radioactivity to members of the public remains at a small fraction of the dose limit. As the spent fuel canisters are sealed and the contents blanketed in an inert gas, the ISFSI facility does not release liquid or gaseous effluents, and the direct radiation component, including skyshine, is the only radiological impact attributable to the ISFSI operations.

c. There were 21 liquid batch releases completed between January and December 2023.

Gaseous releases were elevated and continuous from the Main Stack. There were no elevated batch or ground level continuous gaseous effluents in 2023. Inputs to the Main Stack include gaseous effluents from the Reactor Building, New Radwaste, and Old Radwaste Buildings. In 2023, the Main Stack was monitored for particulate activity (weekly filter collections). Tritium effluents were calculated based on reactor cavity evaporation. In 2023, the primary gaseous effluent released from the Main Stack was tritium.

III. Appendices Appendix A - Effluent, Waste Disposal, and Dose Tables Appendix B - Error Estimation Appendix C - Errata Appendix D - ODCM Revisions Appendix E - Revisions to the Process Control Program (PCP)

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 20 Appendix A - Effluent, Waste Disposal, and Dose Tables Table A-1: Gaseous Effluents - Summation of All Releases Summation of All Releases Units Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Uncertainty4 Fission and Activation Gases Ci

<LLD1

<LLD

<LLD

<LLD

<LLD

+ 25%

Average Release Rate

µCi/s N/A N/A N/A N/A N/A

% of Limit N/A2 N/A N/A N/A N/A Iodines (Halogens)

Ci

<LLD

<LLD

<LLD

<LLD

<LLD

+ 18%

Average Release Rate

µCi/s N/A N/A N/A N/A N/A

% of Limit N/A N/A N/A N/A N/A Particulates Ci

<LLD

<LLD

<LLD 4.80E-11 4.80E-11

+ 18%

Average Release Rate3

µCi/s N/A N/A N/A 1.79E-11 1.79E-11

% of Limit*

N/A N/A N/A 1.68E-05 8.40E-06 Tritium Ci 6.06E-01 8.05E-01 6.80E-01 4.41E-01 2.53E+00

+ 23%

Average Release Rate

µCi/s 6.80E-04 1.20E-03 9.51E-04 9.05E-04 3.74E-03

% of Limit*

7.08E-07 2.35E-06 1.72E-06 1.26E-06 6.04E-06 Gross Alpha Ci

<LLD

<LLD

<LLD

<LLD

<LLD

+ 24%

• % of WB Dose Limit is the criteria used and the actual whole-body dose for the period is compared to that respective limit reported here, in accordance with NUREG 1302, and the Oyster Creek Station ODCM

<LLD1Not Detected: Radionuclides in these categories (Noble Gases, Iodines, Halogens) are not expected at this stage in decommissioning, but the analytical equipment used to quantify these would identify them, if present, so these are listed as not detected at the lower limit of detection (LLD)

N/A2 Not Applicable: Release Rate and % of Limit requires detection of the radionuclides in this class to calculate release rates and compare to limits 3 Average release rate is not based on the actual minutes all batch discharges; it is based on an average of 91 days per quarter as calculated by effluents software (e.g. SEEDS (Simplified Environmental Effluent Dosimetry System)) as this is more conservative in this scenario 4 Error Estimates are calculated in Appendix B

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 21 Table A-2: Liquid Effluents - Summation of All Releases Summation of All Liquid Releases Units Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Uncertainty5 Fission and Activation Products (excluding tritium, gases, and gross alpha)

Ci 0.00E+00 2.31E-05 0.00E+00 0.00E+00 2.31E-05

+15%

Average Concentration2

µCi/ml N/A 3.23E-10 N/A N/A 3.23E-10

% of Limit3 N/A 1.54E-03 N/A N/A 4.62E-04 Tritium Ci 1.49E-01 5.68E-01 9.83E-01 7.76E-02 1.78E+00

+ 15%

Average Concentration

µCi/ml 6.08E-06 7.94E-06 1.35E-05 1.27E-05 4.02E-05

% of Limit3 6.08E-01 7.94E-01 1.35E-01 1.27E-01 1.66E+00 Dissolved and Entrained Gases Ci

<LLD1

<LLD

<LLD

<LLD

<LLD

+ 15%

Average Concentration

µCi/ml

<LLD1

<LLD

<LLD

<LLD

<LLD

% of Limit3 N/A4 N/A N/A N/A N/A Gross Alpha Ci

<LLD1

<LLD

<LLD

<LLD

<LLD

+ 22%

Average Concentration

µCi/ml N/A N/A N/A N/A N/A Volume of Primary System Liquid Effluent (Before Dilution)

Liters 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 Dilution Water Used for Above Liters 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 Volume of Secondary or Balance-of-Plant Liquid Effluent (e.g.,

low-activity or unprocessed) (Before Dilution)

Liters 2.18E+05 6.24E+05 1.16E+06 9.57E+04 2.10E+06 Dilution Water Used for Above Average Stream Flow Liters 2.42E+07 7.09E+07 7.16E+07 6.01E+06 1.73E+08

<LLD 1 Not Detected: Radionuclides were sampled for and not detected in liquid discharges in 2021 and are therefore reported as less than the lower limit of detection (<LLD) 2 Average concentration is the concentration of the effluent at the point of discharge to the canal 3 Percent of limit uses the concentration limit in the 10 CFR 20 Appendix B Table 2, Column 2 ECL for liquid effluent, and the sum of fractions when more than one radionuclide is involved as for F & A products 4 N/A: Not Applicable 5 Error Estimates are calculated in Appendix B

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 22 Table A-2A: Liquid Effluents - Batch Mode Fission and Activation Products Units Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total Mn-54 Ci

<LLD

<LLD

<LLD

<LLD

<LLD Co-58 Ci

<LLD

<LLD

<LLD

<LLD

<LLD Co-60 Ci

<LLD

<LLD

<LLD

<LLD

<LLD Zn-65 Ci

<LLD

<LLD

<LLD

<LLD

<LLD Cs-137 Ci

<LLD

<LLD 8.12E-06 4.48E-06 1.26E-05 Fe-55 Ci

<LLD

<LLD

<LLD

<LLD

<LLD Sb-125 Ci

<LLD

<LLD 1.71E-05

<LLD 1.71E-05 Totals Ci

<LLD

<LLD 2.52E-05 4.48E-06 2.97E-05 Dissolved and Entrained Gases Units Quarter 1 Quarter 2 Quarter 3 Quarter 4 Total (List Others)

Ci

<LLD

<LLD

<LLD

<LLD

<LLD Totals Ci

<LLD

<LLD

<LLD

<LLD

<LLD Tritium Ci 4.82E-01

<LLD 5.89E-02 1.12E-01 6.52E-01 Gross Alpha Ci

<LLD

<LLD

<LLD

<LLD

<LLD

<LLD: Less than the Lower Limit of Detection Table A-2B: Liquid Effluents - Continuous Mode There were no Continuous Liquid Releases from Oyster Creek Station in 2023 containing detectable radionuclides, though these are permitted per the Oyster Creek ODCM.

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 23 Table A-3: Low-Level Waste

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 24 Table A-3: Low-Level Waste (continued)

Waste Carrier Details

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 25 Table A-4: Dose Assessments, 10 CFR Part 50, Appendix I Quarter 1 Quarter 2 Quarter 3 Quarter 4 Yearly Liquid Effluent Dose Limit, Total Body 1.5 mrem 1.5 mrem 1.5 mrem 1.5 mrem 3 mrem Total Body Dose1 6.91E-05 4.73E-04 4.44E-04 3.54E-05 9.34E-04

% of Limit 4.61E-03 3.15E-02 2.96E-02 2.36E-03 3.11E-02 Liquid Effluent Dose Limit, Any Organ 5 mrem 5 mrem 5 mrem 5 mrem 10 mrem Organ Dose-Adult Liver 6.90E-05 1.37E-03 4.44E-04 3.54E-05 1.84E-03

% of Limit2 1.38E-03 2.74E-02 8.88E-03 7.08E-04 1.84E-02 Gaseous Effluent Dose Limit, Gamma3 Air 5 mrad 5 mrad 5 mrad 5 mrad 10 mrad Gamma Air Dose 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

% of Limit 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 Gaseous Effluent Dose Limit, Beta Air3 10 mrad 10 mrad 10 mrad 10 mrad 20 mrad Beta Air Dose 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

% of Limit 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 Gaseous Effluent Dose Limit, Any Organ (Iodine, Tritium, Particulates with

>8-day half-life) 7.5 mrem 7.5 mrem 7.5 mrem 7.5 mrem 15 mrem Gaseous Effluent Organ Dose - Adult TB (Tritium, Particulates with > 8-Day half-life) 5.31E-08 1.76E-07 1.29E-07 9.45E-08 4.53E-07

% of Limit 7.08E-07 2.35E-06 1.72E-06 1.26E-06 3.02E-06 1 Highest Total Body dose varies from quarter to quarter between age groups, depending on the mix of radionuclides in the effluent stream, but the highest is reported for each quarter 2 Highest organ dose varies from quarter to quarter depending on the mix of radionuclides in the effluent stream, but the highest is reported for each quarter 3 Dose to air (mrad) is applied to noble gas emissions only - noble gases are no longer created by fission at Oyster Creek or released from site following under normal decommissioning conditions

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 26 Table A-5: EPA 40 CFR Part 190 Individual in the Unrestricted Area Dose Limit Whole Body1 Thyroid1 Any other organ1 25 mrem 75 mrem 25 mrem Gaseous Effluent Dose 4.53E-07 4.53E-07 4.53E-07 Liquid Effluent Dose 9.34E-04 1.84E-03 1.84E-03 Liquid Effluent Dose Well 73 N/A2 N/A N/A Direct Dose Member of Public 4.87 4.87 4.87 Total Dose 4.87E+00 4.87E+00 4.87E+00

% of Limit 1.95E+01 6.50E+00 1.95E+01 1 The 40CFR190 dose is the sum of internal exposure (consumption of food stuffs and water), inhalation and direct radiation in the highest X/Q sector at the site boundary for gaseous releases.

2No water was pumped from Well 73, therefore no tritium dose result. Well 73 is retained in the report due to the possibility of pumping from the well in the future.

Per ODCM Administrative Control 6.2, an assessment of radiation doses to the likely most exposed MEMBER OF THE PUBLIC from nearby uranium fuel cycle sources (including doses from primary effluent pathways and direct radiation) for the previous calendar year must be made to show conformance with 40 CFR Part 190 Gaseous Nearest member of the public was SE sector at 937 meters for gaseous effluents. In 2023 gaseous dose was calculated quarterly using 10-year average meteorology. All significant pathways were assumed to be present.

Direct Dose For direct dose, the highest dose measured with OSLDs at the site boundary where a member of the public could gain non-challenged access is on the nature trail west side of US Route 9 at OSLD location 62. Using methodology presented in Technical Support Document OC-19-007, 2019 ISFSI PROSPECTIVE DOSE EVALUATION, the Annual Dose at this location was 0.3 mrem based on a scenario where members of the public take advantage of the nature trail for walking along US Route 9. The highest dose to a member of the public, assigned for comparison to federal limits, is for members of the public working at the warehouse beyond and west of the site and protected area boundary. This dose of 4.87 mrem is the dose of record assigned and is a fraction of the federal limit as summarized in Table A-5 above.

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 27 Liquid Liquid doses are calculated at the US Route 9 Bridge and Discharge Canal locations for the following exposure pathways: ingestion of fish, shellfish, and direct exposure at the shoreline while swimming.

40 CFR Part 190 Compliance For reporting direct dose to a member of the public, dosimetry measurements (minus average of control stations, occupancy and assumed structure shielding) measured direct radiation for the nearest member of the public (OC-TLD-55). The nearest member of the public for direct radiation is considered an individual that works in the warehouse west of the site.

The nearest resident is in the SE sector at 937 meters.

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 28 Appendix B - Error Estimation Estimates of Total Error Total Estimated Error determination for each release pathway is estimated in accordance with procedure CY-AA-170-2100, Estimated Errors of Effluent Measurements.

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 29 Appendix C - Errata No Errata to Previously Issued ARERRs

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR) 30 Appendix D - ODCM Revisions There were no revisions of the Offsite Dose Calculation Manual in 2023.

2023 OYSTER CREEK ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT (ARERR)

Appendix E - Revisions to the Process Control Program (PCP)

Process Control Program (PCP) Changes - No changes to the Process Control Program were made in 2023.