United States Nuclear Regulatory Commission - Protecting People and the Environment

Morning Report for July 8, 2004

Headquarters Daily Report

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REGION I

STATUS OF DROPPED FUEL PIN RECOVERY EFFORT

Licensee/Facility:

EXELON GENERATION CO., LLC
Limerick 1
PHILADELPHIA, Pennsylvania
Dockets: 05000352
[1] GE-4
License No:
Notification:

MR Number: 1-2004-0003
Date: 07/07/2004

Call from SRI

Discussion:

On July 1, 2004, while Limerick was performing eddy current testing on a used fuel assembly pin (underwater in the spent fuel pool), the fuel pin fell to the bottom of the spent fuel floor. The local area radiation monitors (ARMs) and ventilation monitors did not show an increase in radiation. Later examination of the fuel pin found that both end plugs were dislodged, however the fuel pin was in a stable position and the fuel pellets remained within the pin. Limerick and their fuel inspection vendor, GE, subsequently prepared plans and assembled the necessary tools to recover this fuel pin.

The fuel bundle being tested experienced a leak during its first cycle and was removed from the core during the Spring 2004 refueling outage. Limerick was performing eddy current tests on the bundle to determine which fuel pins had cladding perforations. The pin was being held by a tool that attached to the upper end plug. However, the upper end plug weld failed during the eddy current test causing the fuel pin to drop. The lower end plug most probably became dislodged when the fuel pin hit the floor. GE's initial view is that the upper end plug weld failed due to hydriting caused by water that leaked into the pin through the fuel cladding perforations.

On the afternoon of July 7, 2004, while attempting to recover the fuel pin, six fuel pellets spilled out of the pin onto the bottom of the spent fuel pool floor; no release of radiation was detected following this event. As a precaution, a physical barrier was installed around the work area to prevent the pellets from moving. Four of the six pellets have been placed in a container; Limerick and GE are in the process of recovering the remaining two pellets today. Limerick and GE continue to work on a recovery plan for the dropped fuel pin.

This event did not reach a level requiring a 50.72 report or declaration of an emergency action level.

Regional Action: The resident inspectors continue to monitor the licensee's recovery efforts. A radiation specialist has been dispatched to the site.

Accession Numbers:

Accession No Accession Date
ML041900559 07/07/2004

Contacts:

Name Office Abbrev Phone No E-Mail
HANSELL, S L R1 (610) 327-1344 SLH1@nrc.gov
JOHNSON, DANTE C R1 (610) 337-5287 DCJ1@nrc.gov


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REGION III

Part 21 - 2004-0015-00 - Whiting Crane Slackline Frame Welds

Licensee/Facility:

WHITING CORPORATION
WHITING CORPORATION
MONEE, Illinois
Dockets:

License No:
Notification:

MR Number: H-2004-0015
Date: 06/26/2004


Source Document: E-MAIL from Licensee

Reviewer: LAURA, RICHARD A

Discussion:

Part 21 - 2004-0015-00 - Whiting Crane Slackline Frame Welds

On 26 June 2004, Whiting Corporation, a crane vendor, reported the identification of an overstress condition on certain structural frame welds located on the interior plate of the slack line frame assembly. This frame assembly houses a load sensor which activates a protective limit switch for listing (i.e., tilting) conditions. This frame assembly also transfers a portion of the main load. The overstress condition is limited to the main hoist of a few redundant (single failure proof) cranes having capacities of 125 tons. This problem was identified when the Robinson plant requested calculations be done for an upcoming lift. The vendor stated that affected nuclear power plants are Brunswick (SN 10388 and 10389) and Robinson (SN 10698). These cranes must be limited to operating at 59 tons (47 percent of rated capacity) until the appropriate repairs are made. The vendor indicated that, even if the subject welds had failed, the remaining plates would have taken the load and a load drop would not have resulted.

Contacts:

Name Office Abbrev Phone No E-Mail
LAURA, RICHARD A NRR (301) 415-1837 RAL1@nrc.gov
Page Last Reviewed/Updated Thursday, March 29, 2012