Sep 29, 2024: The case against restarting Three Mile Island’s Unit-1

Peach Bottom Atomic Power Station - Mid-Cycle Letter for Peach Bottom Atomic Power Station (05000277/2011006 AND 05000278/2011006)

ADAMS Accession No. ML112411345

From the U.S. Nuclear Regulatory Commission:

This year has seen a dramatic increase in a question people regularly ask the Nuclear Regulatory Commission: “What magnitude earthquakes are U.S. nuclear power plants designed to withstand?” The answer, however, does not include a specific “magnitude.”

The NRC requires U.S. reactors to withstand a predicted level of ground motion, or acceleration, specific to a given site. Ground acceleration is measured in relation to “g,” the acceleration caused by Earth’s gravity.

An earthquake’s magnitude, often described on the Richter scale, is an expression of how much energy the quake released. It’s not possible to transform a given magnitude alone to ground acceleration at a site. Several important factors affect the relationship between an earthquake’s magnitude and associated ground acceleration, including the distance from the earthquake, the depth of the quake and the site’s local geology (i.e., hard rock or soil). A small earthquake close to a site could therefore generate the same peak ground acceleration as a large earthquake farther away.

The NRC’s requirements call for a nuclear power plant’s design to account for ground acceleration that is appropriate for its location, given the possible earthquake sources that may affect the site and the makeup of nearby faults, etc. Existing U.S. plants were designed on a “deterministic” or “scenario earthquake” basis. In other words, examination of an area’s seismological history provides an understanding of the largest earthquake and associated ground acceleration expected at a plant site.

Later this year, the agency expects to provide existing plants a seismic analysis tool based on work related to applications for new plants, along with the latest information on earthquake sources, so that the plants can perform an updated review. Applications for new nuclear power plants have taken a “probabilistic” approach to determining seismic hazards, looking at a wide range of possible quakes from sources that could affect a given site. The NRC has spent several years examining how these newer techniques can be used to re-evaluate existing nuclear power plant sites.

From NRC News:

The Nuclear Regulatory Commission will present information during the National Academy of Sciences’ (NAS) fifth committee meeting on the NRC-sponsored study, “Analysis of Cancer Risks in Populations Near Nuclear Facilities: Phase 1.” The meeting’s public session will run from 1:20 p.m. – 5 p.m. on Monday, Aug. 29, at the Pew Charitable Trusts Conference Center, 901 E St., NW in Washington, D.C.

The NRC will outline potential next steps for the study and describe the agency’s public outreach and communications efforts. NRC staff will also be available to answer committee member questions. The Environmental Protection Agency will also present information to the committee. The public is welcome to attend and will have the opportunity to comment prior to the end of the meeting. The NAS asks members of the public to register for the meeting, and the NAS website has additional details, although they are subject to change. General questions on the study can be sent via e-mail to: crs@nas.edu.

The NAS project will update the 1990 U.S. National Institutes of Health – National Cancer Institute (NCI) report, “Cancer in Populations Living Near Nuclear Facilities.” The NRC uses the 1990 NCI report as a primary resource when communicating with the public about cancer mortality risk in counties that contain or are adjacent to nuclear power facilities. In the new study, the NRC is asking the NAS to evaluate cancer diagnosis rates, in addition to mortality risk, for populations living near decommissioned, operating and proposed NRC-licensed nuclear facilities. Phase 1 of the NAS study will determine whether a technically defensible approach to meet the goals of the study request is feasible – and if so, the approach will be developed using scientifically sound processes for evaluating cancer risk that could be associated with nuclear facilities.

Exelon Nuclear

FOR IMMEDIATE RELEASE

KENNETT SQUARE, PA. (August 23, 2011) - None of Exelon Nuclear's four Mid-Atlantic nuclear energy stations was affected by this afternoon’s seismic activity in Virginia, and all continue to operate safely at this time. An “Unusual Event” was declared at each of the stations following the seismic activity, in accordance with plant procedures: Peach Bottom Atomic Power Station, Three Mile Island Generating Station and Limerick Generating Station in Pennsylvania, and Oyster Creek Generating Station in New Jersey.

Three Mile Island Nuclear Station, Unit 1 – Issuance of Amendment Re: Relocation of Equipment Load List From Technical Specifications to Updated Final Safety Analysis Report (TAC No. ME4732)
 
Download ML112150486
 

Three Mile Island Nuclear Station, Unit 1 – Issuance of Amendment Re: Relocation of Equipment Load List From Technical Specifications to Updated Final Safety Analysis Report (TAC No. ME4732)
 
Download ML112150486
 

New Data Supports Previous Fairewinds Analysis, as Contamination Spreads in Japan and Worldwide from Fairewinds Associates on Vimeo.

From Majirox News:

Parts of the 20-kilometer (12.42 mile) Evacuation Zone around the radiation-leaking Fukushima Daiichi nuclear plant are close to being declared uninhabitable and the ban on entering the area maintained, possibly for decades, according to the Yomiuri newspaper on Aug. 21.

Prime Minister Naoto Kan is poised to explain the situation to local government leaders from the affected leaders and apologize for evacuation from the area becoming long-term rather than temporary.

Excess radiation dozens of times greater than the acceptable annual safety level in parts of the zone is behind the moves, which thwart national government plans to reopen the area by January next year upon achieving a cold shutdown of the plant, which went into meltdown after the March 11 earthquake and tsunami that hit the Tohoku Region.

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