Abstract
The 1979 accident at the Three Mile Island nuclear power station in Pennsylvania released about 22 million Curies of xenon-133 into the environment. Because physical dosimetry indicated exposures to the nearby population of less than about 2 mSv, discernible impacts to the health of the exposed population are not generally believed to have resulted. However, there is contrary evidence, including especially the results of biodosimetry via cytogenetic analysis using the FISH method. This report examines the discrepancy between the results of physical dosimetry and biodosimetry, which among the small number of persons examined indicated exposures between 600 and 900 mSv. The paradox reveals a fundamental error in the health physics body of knowledge: the definition of the energy imparted to tissue, ε, fails to properly account for the temporal distribution of ionization products resulting from dilute contamination with an internally incorporated beta-emitting radionuclide. Application of a century-old result describing “shot noise” in an electronic system repairs the deficiency. The Xe-133 concentration in the tissue of those individuals exposed to the most intense portion of the radioactive plume released from the TMI facility is shown to have been on the order of 0.1 μCi/l, persisting for multiple hours. Shot noise reference doses in the range from 820 to 1,700 mSv follow, a result which is consistent with biodosimetric analysis. The finding should motivate a comprehensive re-evaluation of the conventional understanding of the 1979 accident at the Three Mile Island nuclear power station, especially regarding its impact upon the population of the surrounding area.
"Correcting that single omission, it is shown that the true biological impact to those most exposed to radioactive releases from the damaged facility (measured as a reference dose) lies in the range at or above 1,000 mSv. The exposure is sufficient to explain acute effects observed at the time of the accident, including radiation sickness."
Nuclear Regulatory Commission - News Release
No: 20-038 July 9, 2020
CONTACT: David McIntyre, 301-415-8200
 
NRC Submits Report to Congress on Best Practices for Community Advisory Boards
 
Near Decommissioning Nuclear Power Plants
The Nuclear Regulatory Commission has submitted to Congress its report on best practices for community advisory boards associated with decommissioning activities at nuclear power plants. The report was mandated by the Nuclear Energy Innovation and Modernization Act.
 
To prepare the report, NRC staff conducted 11 public meetings from August through October 2019 to obtain insights from host states, communities near nuclear power plants, and existing community advisory boards. Staff also conducted two webinars to provide people unable to attend the meetings in person an opportunity to participate in the process.
 
The NRC staff used public comments from these meetings, responses to a questionnaire issued in September, and direct outreach to state and local officials and organizations to compile its report. The NRC received 1,235 oral and written comments from 216 commenters through these outreach efforts.
 
The report to Congress is available on the NRC website.
 
Nuclear Regulatory Commission - News Release
No: I-20-015 July 6, 2020
Contact: Diane Screnci, 610-337-5330 Neil Sheehan, 610-337-5331
 
NRC Senior Resident Inspector Newly Assigned to Limerick Nuclear Power Plant
 
Nuclear Regulatory Commission officials in King of Prussia, Pa., have selected Adam Ziedonis as the new senior resident inspector at the Limerick Generating Station. The two-unit site is operated by Exelon Nuclear and is located in Limerick, Pa.
 
Ziedonis joins NRC Resident Inspector Sherlyn Haney at Limerick.
 
Most recently, Ziedonis was the senior resident inspector at the Hope Creek Generating Station in Hancocks Bridge, N.J. He has also been a resident inspector at the Salem nuclear power plant in Hancocks Bridge, N.J., and the Peach Bottom Atomic Power Station in Delta, Pa., and a region-based reactor inspector.
 
Ziedonis joined the agency’s Region I office in 2004 after earning his bachelor’s and master’s degrees in mechanical engineering from Drexel University in Philadelphia. He is a graduate of the NRC’s Nuclear Safety Professional Development Program and a registered Professional Engineer in the Commonwealth of Pennsylvania.
 
Each U.S. commercial nuclear power plant has at least two NRC resident inspectors who serve as the agency's eyes and ears at the facility, conducting inspections, monitoring major work projects and interacting with plant workers and the public. Resident inspectors are assigned to a site for up to seven years.
 
Subject:  Three Mile Island Nuclear Station, Unit 1 - Exemption Request from Certain Requirements of 10 CFR Part 73, Appendix B, "General Criteria for Security Personnel" (EPID L-2020-LLE-0096 [COVID-19])
 
ADAMS Accession No. ML20161A391
 

Subject:  Dresden, LaSalle, Limerick, Nine Mile Point, Peach Bottom, Quad Cities - Individual Notice of Consideration of Issuance of Amendments to Renewed Facility Operating Licenses, Proposed No Significant Hazards Consideration Determination, Opportunity for Hearing (Letter and Federal Register Notice)

ADAMS Accession Nos.: ML20156A365 (Letter); ML20156A400 (FRN)

Nuclear Regulatory Commission - News Release
No: 20-036 June 23, 2020
CONTACT: David McIntyre, 301-415-8200
 
NRC Identifies Nine Abnormal Occurrence Events in FY 2019 Annual Report to Congress
 
The Nuclear Regulatory Commission has published its annual report to Congress for fiscal year 2019 regarding Abnormal Occurrences involving the medical and industrial uses of radioactive material.
 
Nine Abnormal Occurrences were identified, seven of which were medical events, such as misadministration of radioactive material in diagnosis or treatment of an illness. One event involved a worker exposure, and the final event was the theft and subsequent recovery of a device containing a risk-significant radioactive source. No events at commercial nuclear power plants in FY 2019 met the criteria requiring an Abnormal Occurrence declaration.
 
U.S. law defines an Abnormal Occurrence as an unscheduled incident or event that the NRC determines to be significant from the standpoint of public health or safety. The NRC sets specific criteria, most recently updated in October 2017, for determining which events qualify.
 
The Report to Congress on Abnormal Occurrences, Fiscal Year 2019, is available on the NRC website as NUREG 0090, Volume 42.
 
Nuclear Regulatory Commission - News Release
No: 20-033 June 15, 2020
CONTACT: Office of Public Affairs, 301-415-8200
 
NRC Accepts License Application for Oklo Advanced Reactor
 
The Nuclear Regulatory Commission has accepted for review a Combined License application from Oklo Power LLC. to build and operate the company’s Aurora reactor at the Idaho National Laboratory site in Idaho.
 
The proposed Aurora design uses heat pipes to transport heat from the reactor core to a supercritical carbon-dioxide power conversion system to generate electricity. Oklo’s application, submitted on March 11, seeks approval of the first NRC license for an advanced non-light-water reactor design. The NRC and Oklo have engaged in “pre-application” discussions since 2016.
 
Accepting the application for review, or “docketing,” does not indicate whether the Commission will ultimately approve or reject the request for a license. The NRC is focusing on aligning on key design and safety aspects early in the process to provide a predictable and efficient licensing schedule. Information regarding the Combined License process is available on the NRC website.
 
In the near future, the NRC expects to publish in the Federal Register a notice of opportunity to intervene in an adjudicatory hearing on the Combined License. Petitions to intervene in a hearing must be filed within 60 days of the notice, by anyone whose interest may be affected by the proposed license and who wants to participate as a party in the proceeding. More information on the hearing process is available on the NRC website.
 

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