05000237/FIN-2011005-03
From kanterella
Jump to navigation
Jump to search
Finding | |
|---|---|
| Title | Unplanned Unit 2 Secondary Containment TS Entry |
| Description | On December 21, 2011, WO 1450006-01, D2 SA PM 517 RB/TB INTLK DOOR (2-5850-52) ELECTRICAL CHECKS, was being performed to ensure the reactor building interlock doors were functioning properly. During the performance of this work, connection point A19 was lifted to measure the in-line current of the door magnet for reactor building interlock door 52 (EPN 2-5850-52). By lifting connection A19, turbine building interlock door 16 (EPN 2-5850-16) lost power to its locking magnets. This loss of power caused both doors of the Unit 2 interlock to be open (door 52 was being held open and did not lose power due to this). This caused alarm 902-4 E-19, RX/TURB 517 INTLK DOORS INOP/BYP to occur. This condition existed for 9 seconds. This caused entry into TS 3.6.4.1, Condition A, Secondary Containment Inoperable in Mode 1, 2, or 3, and resulted in a subsequent event notification report, event number 47540. The reactor building serves as the secondary containment structure. The primary purpose of the secondary containment is to minimize the ground level release of airborne radioactive materials and to provide for a controlled, elevated release of the building atmosphere under accident conditions. There are two personnel air locks between the turbine building and reactor buildings at grade elevation (i.e., 517 feet). Each pair of personnel access control doors is electrically interlocked so that only one of the pair may be open at a given time. At the end of the inspection period, the licensee was still working on a root cause to identify all causal factors related to this issue. The inspectors plan to review the root cause report and determine if there were any violations of NRC requirements and that appropriate corrective actions were applied. The inspectors considered this issue to be an unresolved item (URI) pending evaluation efforts |
| Site: | Dresden  |
|---|---|
| Report | IR 05000237/2011005 Section 4OA3 |
| Date counted | Dec 31, 2011 (2011Q4) |
| Type: | URI: |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71153 |
| Inspectors (proximate) | G Roach D Melendez-Colon C Phillips T Go J Cameron M Learn R Edwardsr Langstafft Briley T Go A Shaikh B Kemker C Phillips D Lords D Melendez Colon F Ramirez J Cameron J Corujo Sandin M Bielby P Smagacz R Jickling |
| INPO aspect | |
| ' | |
Finding - Dresden - IR 05000237/2011005 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Finding List (Dresden) @ 2011Q4
Self-Identified List (Dresden)
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||