ML22088A217
| ML22088A217 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 03/16/2022 |
| From: | NRC Region 1 |
| To: | Christopher Hanson NRC/Chairman |
| Snyder A | |
| References | |
| Download: ML22088A217 (33) | |
Text
Overview of Pilgrim Liquid Discharge Considerations Briefing for NRC Chairman Hanson U.S. NRC Region 1 - Pilgrim Station 16 MAR 2022
Agenda
- 1. Review of Regulatory Approach to Effluents
- 2. History of Effluent Releases at Pilgrim
- 3. History of Environmental Monitoring Near Pilgrim
- 4. Tritium in Perspective
- 5. Radiopharmaceuticals in Comparison
- 6. YOUR questions 2
- 1. The Regulatory Approach
- 10 CFR 20 (U.S. NRC)
- 40 CFR 190 (U.S. EPA)
- NPDES Permit (State of Massachusetts and EPA) 3
Regulations - NRC
- Radiation safety regulations apply to all types of NRC licensees (medical, manufacturing, power, etc)
- Objectives based (What vs How)
- Radiation dose-based
- Absorbed dose is the best indicator of potential health risks
- Regulatory limits are not safety limits (10 CFR 20) 4
NRC - 10 CFR 20 5
NRC - 10 CFR 20 6
NRC - 10 CFR 20 Another Option Available 7
EPA - 40 CFR 190 8
EPA - 40 CFR 190 H-3 (Tritium) not listed 9
Existing NPDES Permit 10
Existing NPDES Permit 11
12 Water is Fungible - Can water in the Spent Fuel Pool be handled differently?
- 2. History of Effluent Releases Publicly available at: https://www.nrc.gov/reactors/operating/ops-experience/tritium/plant-info.html 13
0 1
3 0
4 6
29 5
21 1
7 2
2 0
0 0
0 50000 100000 150000 200000 250000 300000 350000 0
5 10 15 20 25 30 35 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Number of liquid releases Year Number of Liquid Releases & Volume - Pilgrim Station Volume (gallons)
Number of Releases 14
0 0.141 0.23 0
1.98 2.48 4.43 0.099 6.2 0.0039 3.56 0.0015 0.00082 0
0 0
0 50 100 150 200 250 300 350 400 450 500 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 Tritium Activity Released (Curies)
Year Comparison of Annual Tritium Releases, Gas & Liquid - Pilgrim Liquid Releases Gas Releases Note: values in the blue call-outs show the activity of Tritium in the liquid release, in Curies 15
3.00 0.90 0.57 0.10 0.05 0.12 0.08 0.03 0.03 0.05 0.02 0.02 0.02 0.05 0.01 0.00 0
20 40 60 80 100 120 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 Dose from ALL Radionuclides in millirem Year Comparison of Liquid and Gas Releases to Limits - Pilgrim Liquid Releases Gas Releases Note: values in the blue call-outs show the TOTAL whole-body dose for ALL radionuclides and ALL releases in that year NRC annual whole-body dose limit as found in 10 CFR 20.1301 EPA annual whole-body dose limit as found in 40 CFR 190 Typical whole-body dose from one transcontinential flight in the summer season (4 millirem) 16
- 3. History of Environmental Monitoring Publicly available at: https://www.nrc.gov/reactors/operating/ops-experience/tritium/plant-info.html 17
Radiological Environmental Monitoring Program
- Required as part of the facilitys licensing basis
- Results reported annually
- Described in Regulatory Guide 04-001
- Objectives
- Evaluate the local environment to establish a baseline prior to operation
- Determine if any measurable radiation or radioactive materials are attributable to plant operation
- Determine if any measurable radiation or radioactive materials that are attributable to plant operation are commensurate with the reported effluents and meet design objectives 18
Samples and Monitoring 19
Sampling Results - Aquatic Edibles 2020
- Shellfish:
- Blue mussels and soft-shelled clams
- Natural K-40 detected, as expected
- No plant-related radionuclides, results similar to pre-operational period
- Lobster:
- Collected from outfall June, July, August, September
- Results same as shellfish
- Fish:
- Some species harder to collect as warm discharge water has stopped
- Results same a shellfish 20
Sample Results - Surface Water 2020 Release Point Note: No H-3 (tritium) was detected in 2011, the year with the largest number of liquid releases Sample Point 21
- 4. Tritium in Perspective
- A radioactive isotope of Hydrogen (one proton, two neutrons)
- Produced naturally in the upper atmosphere when cosmic rays interact with Nitrogen atoms (along with C-14 and Be-7)
- Produced by reactors, however releases are at fractions of the natural background production rate [EPA fact sheet]
- Can be found at very low concentrations in lakes and streams (about 4 pCi/L)
- Radiation emitted as Beta particles of very low energy (cannot penetrate the skin surface)
- Rapidly incorporates with water molecules and cannot be removed
- Because water turns over rapidly in the body, tritium in the body is rapidly cleared from tissues [EPA fact sheet, 10-day biological half-life]
22
23 0.1 18.6 50.0 26.9 25,271.0 68,450.0 0
10,000 20,000 30,000 40,000 50,000 60,000 70,000 80,000 H-3 K-40 Cs-137 Co-60 Ra-226 Th-232 Relative Risk (millirem per microCurie ingested)
Radionuclide Comparison of Tritium Risk to Other Radionuclides https://www.epa.gov/radiation/federal-guidance-report-no-11-limiting-values-radionuclide-intake-and-air-concentration
Popular shopping site Tritium activity not even listed No warning or precautions Found online Each watch contains 27,000 microCuries of H-3 24
- 5. Radiopharmaceuticals in Comparison 25 https://www.ncbi.nlm.nih.gov/books/NBK234160/
- 5. Radiopharmaceuticals in Comparison 26 https://www.ncbi.nlm.nih.gov/books/NBK234160/
27 This Photo by Unknown Author is licensed under CC BY-NC
Supplementary Slides 28
29
Dose Calculations - Assumptions and Example Fish: 21 kg/yr Shellfish: 9 kg/yr Swimming: 52 hrs/yr Boating: 52 hrs/yr 30
Groundwater - 2020 Annual Report EPA Drinking Water Standard:
- Assumes that all drinking water in a year contains tritium at this level
- Is assumed to equal 4 mrem/yr (not correct and a significant over-estimate) 31
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