ML15012A601

LTR-14-0729 -Tom Gurdziel Email Pressurized-Water Reactor Loose Parts Monitor Alarm at SONGS - Region Iv Response

ML15012A601
Person / Time
Site:	San Onofre
Issue date:	01/12/2015
From:	Dricks V L Office of Public Affairs Region IV
To:	Tannenbaum A M NRC Region 4
AMT / V. Dricks
References
Download: ML15012A601 (2)

Text

From:Dricks, VictorTo:Tannenbaum, Anita

Subject:

FW: SONGS loose parts monitorDate:Monday, January 12, 2015 3:01:54 PMPlease enter my response to Tom Gurdziel into ADAMS Victor DricksSenior Public Affairs OfficerU.S. Nuclear Regulatory Commission / Region IV1600 E. Lamar Blvd.

Arlington, Texas 76011(817) 200-1128 (Office)(817) 983-1992 (Cell) From: Dricks, Victor Sent: Monday, January 12, 2015 3:01 PMTo: Tom Gurdziel (tgurdziel@twcny.rr.com)

Subject:

SONGS loose parts monitor

Dear Mr. Gurdziel:

Thank you for your e-mail of Dec. 28, 2014, to Chairman AllisonMacfarlane, regarding the loose part monitor at the San Onofre Nuclear GeneratingStation, on whose behalf I am responding.

The vibration and loose part monitoring system is designed for early detection of loose metallic parts in the primary system. Early detection can provide the time required to avoid or mitigate damage to, or malfunction of, primary system components. Due to the sensitivity of the monitors, spurious alarms occur on occasion. Operators are required to investigate the cause of these alarms to determine if there is an actual loose part in the steam generator.

The NRC resident inspectors were aware of the vibration and loose parts alarms during the operating cycle preceding the steam generator tube leak in January 2012, and identified this issue for follow-up to the AIT inspection. A follow-up inspection of the unresolvedissues identified by the AIT was conducted from August 20 to September 28, 2012. That inspection determined that the licensee properly responded to and evaluated the loosepart monitor alarms according to vendor recommendations.

The licensee also requested from Westinghouse an in-depth evaluation of the acoustical data. The results of that analysis were inconclusive because of limitations with themonitoring system. Specifically, because of sensor locations (lower portion of the steam generator below the tube sheet in the support structure) and sensitivity, it was not possible to determine the exact source of the Unit 3 alarms. Westinghouse engineering personnel performed an evaluation of acoustical data and determined from the shape and intensity of the particular responses that the acoustic source was not likely from the upper bundle of the replacement steam generator or related to the tube-to-tube wear.

Victor DricksSenior Public Affairs Officer U.S. Nuclear Regulatory Commission / Region IV1600 E. Lamar Blvd.Arlington, Texas 76011(817) 200-1128 (Office)(817) 983-1992 (Cell)

Good morning, Tom Gurdziel <tgurdziel@twcny.rr.com>Sunday, December 28, 2014 7:29 PMCHAIRMAN ResourceDricks, Victor; Screnci, Diane; Mitlyng, Viktoria; Michael Mulligan; Bridget Frymire PWR Loose Parts Monitor: A Repeating Nuisance Alarm? As I was throwing away my no longer useful, handwritten comments on the SONGS replacement steam generators, Inoticed a problem that I do not believe has been addressed by the Nuclear Regulatory Commission.According to my notes, the SONGS AIT report, (ML12188A748), describes about 30 "valid" vibration and loose partsalarms at San Onofre. My recollection is that these alarms were described as valid although nocause had been identified for any alarm. Does it make sense to keep in service, inaccurate PWR monitoring equipment?

Thank you,Tom Gurdziel On page 22 of the referenced report, you will find that all the alarms apparently occurred betweenFebruary 18, 2011 and January 31, 2012. (This would not be even one complete year.)Is there any NRC group responsible for seeing that PWR nuisance alarms get addressed? Is there anyrecommended response time?