ML12200A222
| ML12200A222 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 12/01/2011 |
| From: | Haskell R Office of Nuclear Reactor Regulation |
| To: | |
| References | |
| FOIA/PA-2012-0121 | |
| Download: ML12200A222 (1) | |
Text
Sakai, Stacie From:
Haskell, Russell ýY"'WX L Sent:
Thursday, December 01, 2011 4:55 PM
Subject:
New OpE Forum Posting: DAVIS BESSE - CRACKS DISCOVERED IN SHIELD BUILDING DURING REACTOR VESSEL HEAD REPLACEMENT Follow Up Flag:
Follow up Flag Status:
Completed This email is being sent to notify recipients of a new posting on the (Operatina Experience Community Forum. Recipients are expected to review the posting for applicability to their areas of regulatory responsibility and consider appropriate actions. However, information contained in the posting is not tasking; therefore, no specific action or written response is required.
Information Security Reminder: OpE COMMs contain preliminary information in the interest of timely internal communication of operating experience. OpE COMMs may be pre-decisional and may contain sensitive/proprietary information. They are not intended for distribution outside the agency DAVIS BESSE - CRACKS DISCOVERED IN SHIELD BUILDING DURING REACTOR VESSEL HEAD REPLACEMENT (click link)
Summary On October 10, 2011 a crack was discovered in the units Shield Building wall. At time of discovery, licensee contractors were performing hydro-demolition activities to create a construction opening for replacement of the existing Reactor Vessel Closure Head. The crack thickness was characterized as very tight (<0.01 inch thick) and confined to the fluted area of the Shield Building. Davis Besse remains shutdown in MODE 5. Agency technical reviewers continue to evaluate licensee's structural calculations.
This COMM has been posted to the following communities: All Communications, Containment (leakage, degradation, cooling system performance), Emergency Preparedness, Flood Protection & Missiles, Inspection Programs, Materials/Aging, Natural Phenomena, New Reactors, Power Uprate, Structural To unsubscribe from this distribution list or to subscribe to a different list on the OpE Community, please visit:
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Thank you for reviewing and using Operating Experience.
Russell S. Haskell II United States Nuclear Regulatory Commission (NRC)
Reactor Systems Engineer (NRR/DIRS/IOEB)
Russell.Haskellk.nrc.pov I 301.415.1129 1 O-7H23