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Exelon Generation Company, LLC; Notice of Issuance of Director's Decision Under 10 CFR 2.206

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Notice is hereby given that the Director, Office of Nuclear Reactor Regulation, has issued a director's decision with regard to a petition dated March 2, 2005, filed by Mr. Barry Quigley, hereinafter referred to as the “petitioner.” On March 4, 2005, the petitioner provided additional clarifying information during a conference call with the Petition Review Board. The conference call was recorded; a transcript is publicly available in the Nuclear Regulatory Commission's (NRC's) Agencywide Document Access and Management System (ADAMS) at Accession No. ML050870619. The petition concerns the operation of the Byron Station, Unit 1 which is owned and operated by Exelon Generation Company, LLC (Exelon).

The petition requested that the NRC take enforcement action against Exelon's Byron Station for failure to comply with 10 CFR part 50, Appendix B, Criterion XVI. Specifically, the petitioner stated that the 1C loop stop isolation valve (LSIV) has been broken for at least 6 years and has not been repaired.

The petition of March 2, 2005, raises concerns originating from the condition that the 1C LSIV can be difficult to close, to the point that the protective features of the motor actuate. The petitioner indicated that the failure mechanism is metal-to-metal contact between the valve disc and a misaligned valve guide which introduces debris into the reactor coolant system (RCS).

A public meeting with Exelon was held in the NRC Region III offices on March 21, 2005; a summary of the meeting is available at ADAMS Accession No. ML050820530. The petitioner was in attendance and offered comments prior to adjournment of the meeting. The licensee made several submittals containing additional information regarding the LSIV performance and testing as well as a May 27, 2005, response to an NRC staff Request for Additional Information.

As a result of evaluation of the information provided, the NRC prepared a proposed Director's Decision, copies of which were sent to the petitioner and to the licensee for comment on July 29, 2005, and August 1, 2005, respectively. The petitioner responded with comments on August 14, 2005, and the licensee responded on August 12, 2005. The comments and the NRC staff's response to them are included in the Director's Decision.

The Director of the Office of Nuclear Reactor Regulation has determined that the request to take enforcement action against Exelon's Byron Station for failure to comply with 10 CFR part 50, Appendix B, Criterion XVI, be denied. The reasons for this decision are explained in the director's decision pursuant to Title 10 of Code of Federal Regulations (10 CFR) Section 2.206 DD-05-05, the complete text of which is available in ADAMS for inspection at the Commission's Public Document Room, located at One White Flint North, Public File Area O1 F21, 11555 Rockville Pike (first floor), Rockville, Maryland, and from the ADAMS Public Library component on the NRC's Web site,​reading-rm.html (the Public Electronic Reading Room).

The staff concluded that the 1C LSIV (which does not perform a safety function) is unlikely to be degraded to a condition where the valve guides, or a portion of the valve guides, can loosen and migrate to the reactor vessel during normal plant operation. Nevertheless, the NRC considered the potential for the release of loose parts into the RCS at Byron Station, Unit 1. The NRC concluded that loose parts from the 1C LSIV have an acceptability low potential of occurrence. Even so, the licensee has provisions to locate, identify, and respond to both large and small loose parts. Further, because the licensee complies with NRC Staff Position RSB 5-1, “Design Requirements of the Residual Heat Removal System,” the NRC is assured that for LSIV loose parts scenarios that postulate obstruction of the chemical and volume control system letdown line or obstruction of the pressurizer spray line/nozzle will not prevent safe shutdown of Byron Station, Unit 1.

A copy of the Director's Decision will be filed with the Secretary of the Commission for the Commission's review in accordance with 10 CFR 2.206 of the Commission's regulations. As provided for by this regulation, the Director's Decision will constitute the final action of the Commission 25 days after the date of the decision, unless the Commission, on its own motion, institutes a review of the director's decision in that time.

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Dated at Rockville, Maryland, this 8th day of November, 2005.

For the Nuclear Regulatory Commission.

J.E. Dyer,

Director, Office of Nuclear Reactor Regulation.

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[FR Doc. E5-6307 Filed 11-15-05; 8:45 am]