ML24304B040
| ML24304B040 | |
| Person / Time | |
|---|---|
| Issue date: | 10/28/2024 |
| From: | NRC Region 1 |
| To: | |
| References | |
| Download: ML24304B040 (1) | |
Text
Briefing for Herring Pond Wampanoag Tribe Cultural Council on Pilgrim Effluent Releases NRC Region I October 28, 2024
Outline
- NRC background and role at Pilgrim
- Waste disposal pathways
- Applicable regulations and limits
- Monitoring and reporting
- Pilgrims use of heaters and gaseous effluent releases
- Questions / Discussion
U.S. Nuclear Regulatory Commission
- Independent Executive Branch agency
- Reactors, Materials, Waste
- Region I oversees six actively decommissioning reactor sites
- NRCs function at Pilgrim
- Region 1 inspectors perform routine inspections under IMC 2561 Decommissioning Power Reactor Inspection Program
- Headquarters reviews and approves licensing actions including licensing termination The NRC licenses and regulates the Nations civilian use of radioactive materials to provide reasonable assurance of adequate protection of public health and safety, to promote the common defense and security, and to protect the environment
Radioactivity Units
- Millirem (mrem)
- Unit of dose to a human body
- Curie (Ci)
- Quantity of radioactive material
- Related to number of decays over time
Radioactive Waste Disposal Methods
Radioactive Effluent Regulations
- Dose based; not safety limits
- 10 CFR 20.1301 Dose limits for individual members of the public
- Total dose from licensed operations cannot exceed 100 mrem in a year
- EPA 40 CFR Part 190
- Annual dose to the public limited to 25 mrem as a result of planned discharges to the environment from fuel cycle operations
Effluent Monitoring and Reporting
- Reactor building vent release point is sampled weekly for tritium and particulates in air
- Environmental samples collected to determine if any plant-derived material is detectable in the environment
- Air samples, surface water, sediment, aquatic foodstuffs
Effluent Monitoring and Reporting
- Results reported to the NRC and made public in Annual Radioactive Effluent Release Report and Annual Radiological Environmental Operating Report
- Effluent and environmental monitoring inspected annually
Evaporation at Pilgrim
- Refueling floor has three interconnected open pools of water; dryer-separator pit, reactor cavity, and spent fuel pool
- Evaporation from the spent fuel pool has always occurred, especially when spent fuel raised the water temperature
Evaporation at Pilgrim Immersion heaters installed in early 2023. NRC inspectors reviewed to verify the change was in accordance with the licensing basis and did not require prior NRC approval Heaters have increased the water temperature (up to about 100°F) and rate of evaporation Tritium (H3) is the primary radionuclide that will evaporate Image: Holtec International
- Radioactive isotope of hydrogen (3H), incorporated into water molecule (HTO)
- Weak beta emission, cannot penetrate skin
- Biological half-life 10 days, 40 days for small amount that is organically bound
- Dose per quantity of intake very small
- Used in self-luminous exit signs, watches, gun sights Image: General Atomics
Pilgrim Gaseous Releases
- 4.31 Ci of tritium reported released in 20231; heaters were in operation ~5 months
- 0.00031 mrem dose to the public from tritium and particulates
- Median gaseous tritium release from operating boiling water reactors was 38.6 Ci in 20212 1 Pilgrim 2023 ARERR, ML24135A321 2 NUREG/CR-2907, Vol. 27
Pilgrim Gaseous Releases 0
5 10 15 20 25 30 35 40 2018 2019 2020 2021 2022 2023 Tritium (Ci)
Year Pilgrim Annual Tritium Releases 0.014 mrem
QUESTIONS/DISCUSSION