ML100780355

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Email from Ronald Lavera, NRO to Steven Garry, NRR and Richard Conatser, NRR FW: Ioeb Clearinghouse'S Screening Summary for Monday, November 23, 2009
ML100780355
Person / Time
Site: Three Mile Island  Constellation icon.png
Issue date: 11/23/2009
From: Ronald Lavera
NRC/NRO/DCIP/CHPB
To: Conatser R, Steven Garry
Division of Inspection and Regional Support
References
45514, FOIA/PA-2010-0118
Download: ML100780355 (2)


Text

Page I of 2 From: LaVera, Ronald Sent: Monday, November 23, 2009 3:23 PM To: Garry, Steven; Conatser, Richard

Subject:

FW: IOEB Clearinghouse Screening Summary for Monday, November 23, 2009 Attachments: SEN280.pdf

1) EN 45514 - TMI - RADIATION RELEASE IN CONTAINMENT ASSOCIATED WITH STEAM GENERATOR REMOVAL Note: Lots of media attention to this event since it occurred at TMI.

Approximately 4 PM Saturday 11/21 TMI had an event involving loss of contamination control inside containment. At the time the reactor was defueled with a hole cut in the containment wall to support the ongoing once through steam generators (OTSG) replacement outage. The licensee is not sure atthis time what activity inside containment led to the problem. Their investigation is focusing on two activities (1) "A" piping loop decontamination activities or (2) some work on a drain line on the B" SG.

At the time of the event 175 workers were inside containment. Of these workers 144 people were selected for detailed monitoring based on nasal smears and alarming the portal monitor readings while exiting containment. Ofthe 144, about 20 people have potentially received doses greater than 10 mR. The highest dose to a worker was between 30 and 40 mR. No site worker left the site with external contamination. Airborne contamination levels inside containment have been restored to pre-event levels and cleanup of containment surfaces is in progress. The tarp that was covering the containment opening was contaminated on its inside surface and has been replaced.

At the time of the event there was a slight positive pressure in containment. This condition has been

-corrected and there is now a slight negative pressure in containment. The licensee has performed a release calculation for the period of time where the containment was at positive pressure and determined the maximum release was 0.04 mr. The quarterly limit for a release allowed by their ODCM is 7.5 mr. Therefore, this release is less than 1% of the quarterly limit.

The "A" OTSG, which was in the process of being lifted when this event occurred, is still hanging vertically inside containment. It is being deconned/encapsulated and the licensee hopes to down-end it today onto the transfer mechanism that will eventually move it out through the OTSG opening. The downending process will end up with part of the SG poking out the hole in the containment wall.

This event has generated a significant amount of media interest. Regional OPA and state liason officers have responded to inquiries from multiple'radio, print media and TV stations. They performed a press release at TMI at 2 pm on Sunday, November 22.

The PA governor's office was previously notified and they understand that this is a low level event.

They have some concerns about notification timeliness. The state was notified about 9:30 pm on Saturday (event time was 4 pm). Based on the PA state notification, an event report was filed with the HOO (event number 45514). This event was far below levels that would warrant an unusual event declaration.

TMI still has not determined the root cause for the event.

The Region dispatched a HP inspector and the HP inspection branch chief to the site on Sunday. In addition, the Resident inspector and one other inspector responded to the site for additional coverage.

A Manual Chapter 0309 evaluation was conducted and it was determined that no reactive inspection is warranted at this time. The Region is closely following the licensee's response and will be evaluating their root cause determination once it is issued. (Send to TRGs for Containment; Jerome BettleEP; ocý_

Jeffrey Temple, Health Physics; Steven Garry, Human Performance: Michael Boggi Dose Assessment; Mark Blumberg and Public Affairs; Scott Burnell, assigned to Mike Brown).

  • (i.e., Screened Ireviewed against LIC-401 criteriafor initiating an "Issue for Resolution" (IFR), which is IOEB's process for conducting further evaluation of an issue to determine what, if any, additional mhtml:file://C :\Documents%20and%20Settings\wbc l \Local%20Settings\Temporary%20Int... 2/3/2010

Page 2 of 2 actionS should be taken to communicate and organizationallylearn from OpE.)

      • NOTE:-Tmt

SUMMARY

IS OFFICIAL USE ONLY -- MAY CONTAIN SENSITIVE INTERNAL

-"------N- -'INFORMATION***

DO NOT FORWA ANY PORTIONS"OUTSIDE OF NRC WIT IQ1JT FIRST OBTAINING PERMISSION F"ROM ORIGINATOR Attendees at Screening Meeting:

Mike Brown Dave Garmon-Candelaria Russ Haskell Jesse Robles Mary Wegner - (RES) - by phone Derek Scully - NRO - by phone Steve Pannier Joe Giantelli Mark King - by phone mhtml* :file: //C:\Documents%20and%20Settings\wbc 1\Local%2 0Settings\Temporary%201nt... 2/3/2010