ML18271A153
ML18271A153 | |
Person / Time | |
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Issue date: | 10/11/2018 |
From: | Clint Jones NRC/RES/DSA |
To: | |
Jones C | |
References | |
Download: ML18271A153 (17) | |
Text
NRCs Radiation Protection Policy -
What Does it Take for Change?
Cynthia G. Jones, Ph.D.
U.S. Nuclear Regulatory Commission Office of Nuclear Regulatory Research 1
ANS-HPS Topic Meeting, October 1, 2018
Overview
- Key Milestones for Radiation Protection Policy
- Below Regulatory Concern (BRC) Policy Statements
- Is LNT the Issue? Options for Licensees
- Exploring Case Studies
- LNT & ALARA: Why go beyond ALARA?
- External influencing factors
- Impacts
- Thoughts for the Future 2
ANS-HPS 2018 Topical Meeting, October 1, 2018
Key Milestones*
NRC Radiation Protection Policy 1957: Atomic Energy Commission issues 10 CFR Part 20 1977: ICRP 26 published 1980: BEIR III issued 1980: NRC issues an Advanced Notice of Proposed Rulemaking 1986: NRC issues proposed Part 20 changes 1987: NCRP issues Report 91 1990: NRC Below Regulatory Concern Policy Statement issued 199o-1: ICRP Report 60 issued 1991: NRC issues its revised Part 20 updating it to ICRP 26 & 30 2007: ICRP issues Report 103 2009: NRC: stakeholder outreach to update Part 20 & Part 50, App. I 2016: NRC discontinues Part 20 & Part 50, App. I rulemakings ANS-HPS 2018 Topical Meeting, October 1, 2018 *See also Health Phys. 88(2): 105-124; 2005 3
The Below Regulatory Concern (BRC)
Policy Statements
- NRC issued two BRC policy statements :
- 1986: Radioactive Waste BRC
- 1990: BRC Policy Statement for a consistent risk framework
- Low-Level Radioactive Waste Policy Amendments Act of 1985
- 1991: NRC issues indefinite moratorium on use of the statements
- 1992: Energy Policy Act of 1992 revoked the 1986 and 1990 BRC policy statements
- 1993: Formal withdrawals of BRC Policy Statements and related rulemaking which would have implemented the 1986 BRC Waste Statement
- NRC continues to issue exemptions on a case-by-case basis ANS-HPS 2018 Topical Meeting, October 1, 2018 4
Evolving NRC Policy
- 2009-12: NRC engaged in extensive stakeholder outreach to update Part 20 & Part 50, App. I to reach alignment with ICRP 103
- 2012: NRC Commission direction (SECY-12-0064):
- Update methodology and terminology to align with ICRP 103
- Develop improvements for effective implementation of ALARA
- Continue discussions for dose limits to the lens of the eye & embryo/fetus
- Disapproved reduction of dose limits from 50 mSv/y to 20 mSv/y
- Disapproved SI units
- Improve reporting of occupational exposure
- 2014: Advanced Notice of Proposed Rulemaking for Part 20
- 2015: Advanced Notice of Proposed Rulemaking for Part 50, App I
- SECY-16-0009: Recommendation to discontinue rulemaking
- Dec 2016: NRC discontinues Part 20 & Part 50, App. I rulemakings 5
ANS-HPS 2018 Topical Meeting, October 1, 2018
Is LNT the issue?
What are the Options for Licensees?
Case studies:
- 1. Petition for rulemaking
- 2. Request an exemption
- 3. ALARA & Decommissioning 6
ANS-HPS 2018 Topical Meeting, October 1, 2018
Ex 1: Petition for Rulemaking
- 2015: NRC received 3 similar petitioner requests* to amend Part 20 with regard to the LNT hypothesis (80 FR 35870 )
- Petitioners assert that valid scientific studies and evidence exist that contradicts LNT hypothesis
- Petitioners recommend
- Workers effective doses up to 100 mSv (10 rem) per year if chronic
- Removal of ALARA from the regulations, as it makes no sense to decrease radiation doses that are not only harmless, but may be hormetic
- Raise public dose limits to same level as worker dose limits, as these low doses may be hormetic
- End differing doses limits for pregnant women, embryos and fetuses, and children under 18 years of age 7
ANS-HPS 2018 Topical Meeting, October 1, 2018 *PRM-20-28, PRM-20-29 and PRM-20-30
Current Status of LNT Petitions
- >3,200 public comment letters received
- NCRP Commentary 27* issued in April 2018:
- Review of recent epidemiologic studies support the continued use of the LNT model for radiation protection
- Concluded that no alternate dose-response relationship appears better than LNT
- Currently developing a Commission paper for a decision on petitioners requests
- NCRP Commentary 27, Implications of Recent Epidemiologic Studies for the Linear-Nonthreshold Model and Radiation Protection 8 ANS-HPS 2018 Topical Meeting, October 1, 2018
Ex 2: Exemptions NRC receives and has approved many exemptions to Part 20 based on justification. Examples include:
- SECY-99-077: Approval for a Th licensee to use alternate ICRP internal dosimetry models (ICRP 68); and to approve future exemptions, case-by-case (e.g., fuel cycle facilities)
- SECY-99-136: Exemptions granted to transfer baghouse slag containing <0.05 wt% source material to exempt persons if doses were less than 1 mSv/y (NRC notification if >0.25 mSv)
- SECY-01-0148 : Continuance to consider and grant licensee requests to use the ICRP revised internal dosimetry models on a case-by-case basis 9
ANS-HPS 2018 Topical Meeting, October 1, 2018
Ex 3: ALARA & Decommissioning Current 1997 decommissioning regulations are performance-based and risk-informed:
- NRC terminates ~100 materials licenses/y
- NUREG-1757, V2, R1: Decommissioning Guidance
- Reasonable land use
- Flexibility: screening vs site-specific dose assessment
- No calculations needed for ALARA (App N)
- No need to go below the regulatory limits
- Requests for exemptions (e.g., ICRP 26 72)
- 2002 NRC-EPA MOU: facilitates decision-making 10 ANS-HPS 2018 Topical Meeting, October 1, 2018 See www.nrc.gov/waste/decommissioning.html
LNT & ALARA
- 10 CFR 20.1101(b) - implementation of ALARA
- NRC Regulatory Guide 8.29 (1996)
- Because of the ..absence of scientific certainty regarding the relationship between low doses and health effects, LNT is used as a conservative assumption for radiation protection purposes
- ALARA is intended to be an operating principle rather than an absolute minimization of exposures
- What pushes licensees to go beyond ALARA?
11 ANS-HPS 2018 Topical Meeting, October 1, 2018
Why go beyond ALARA?
ALARA: making a reasonable effort to maintain exposures as far below the limit as is practical
- But licensees have many external factors:
- NRC as the regulator
- Stakeholder questions/concerns
- Other Federal or State regulations
- Accreditation requirements
- Insurance requirements
- Peer pressure to lower doses 12 ANS-HPS 2018 Topical Meeting, October 1, 2018
Where do we go from here?
13 ANS-HPS 2018 Topical Meeting, October 1, 2018
UNSCEAR 2015 Report Attributing Health Effects to Ionizing Radiation Exposure and Inferring Risks
- UNSCEAR highlights the concepts of attributability, inference of risk, and use of collective dose which could impact
- Justification
- Optimization
- Graded approach
- Low doses and associated uncertainties
- The LNT hypothesis & its use in the safety standards
- Challenges in communicating radiation benefits and risks ANS-HPS 2018 Topical Meeting, October 1, 2018 14
Impacts
- Regulatory agencies make changes based upon science, national and international recommendations, and in the U.S., the participatory rulemaking process
- Stakeholder engagement & communication support are needed for paradigm shift
- Educate external influences for a moderate approach
- Focus on the facts that NRC regulations do allow for flexibility to:
- Use risk-informed, performance based approaches for implementation
- Request exemptions to use new models/methodology 15 ANS-HPS 2018 Topical Meeting, October 1, 2018
Thoughts for the Years Ahead
- Completion of the health risk assessment from low-dose/
dose rates (Million Worker Study)
- Improving realism in dose assessment
- Use the UNSCEAR concepts of attribution in practice
- Use of ALARA as designed
- Strong scientific support for a different dose-response relationship
- For change to occur there must be international and national consensus ANS-HPS 2018 Topical Meeting, October 1, 2018 16
Thank you!
For further information, contact:
cynthia.jones@nrc.gov www.nrc.gov 17