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Event Notification Report for May 25, 2001

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           05/24/2001 - 05/25/2001

                              ** EVENT NUMBERS **

38028  38029  38030  

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|General Information or Other                     |Event Number:   38028       |
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| REP ORG:  WA DIVISION OF RADIATION CONTROL     |NOTIFICATION DATE: 05/23/2001|
|LICENSEE:  SWEDISH MEDICAL CENTER               |NOTIFICATION TIME: 18:22[EDT]|
|    CITY:  SEATTLE                  REGION:  4  |EVENT DATE:        05/17/2001|
|  COUNTY:                            STATE:  WA |EVENT TIME:             [PDT]|
|LICENSE#:  WN-M008-1             AGREEMENT:  Y  |LAST UPDATE DATE:  05/24/2001|
|  DOCKET:                                       |+----------------------------+
|                                                |PERSON          ORGANIZATION |
|                                                |MARK SHAFFER         R4      |
|                                                |FRED BROWN           NMSS    |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  TERRY FRAZEE (EMAIL)         |                             |
|  HQ OPS OFFICER:  BOB STRANSKY                 |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|NAGR                     AGREEMENT STATE        |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
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                                   EVENT TEXT                                   
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| AGREEMENT STATE REPORT                                                       |
|                                                                              |
| "ABSTRACT:  A 0.326-millicurie I-125 seed was damaged and leakage occurred.  |
| Five Medi-Physics OncoSeed model 6711 brachytherapy seeds were loaded in a   |
| hollow needle for insertion into a prostate implant patient.  During the     |
| insertion attempt, the needle tip struck bone.  The radiation oncologist     |
| withdrew the needle and determined there was a slight bend in the needle.    |
| In attempting to straighten the needle, the radiation oncologist broke the   |
| needle into two pieces.  The most distal seed was crimped and broken into    |
| two pieces as well.  All items potentially in contact with the broken seed   |
| were immediately isolated.  Contamination on the exterior of the broken seed |
| was 0.012 microcuries.  The patient was not contaminated.  The broken seed   |
| will be held for decay.  Implant personnel were instructed not to bend       |
| loaded needles to prevent this from recurring.                               |
|                                                                              |
| "What is the notification or reporting criteria involved?  WAC 246-221-265   |
| Leaking source                                                               |
|                                                                              |
| "Activity and Isotope(s) involved: 0.326 millicuries of I-125"               |
|                                                                              |
| HOO NOTE: Event entered late - updated for dispatch in 5/25/01 events        |
| package.                                                                     |
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|Power Reactor                                    |Event Number:   38029       |
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| FACILITY: DUANE ARNOLD             REGION:  3  |NOTIFICATION DATE: 05/24/2001|
|    UNIT:  [1] [] []                 STATE:  IA |NOTIFICATION TIME: 21:50[EDT]|
|   RXTYPE: [1] GE-4                             |EVENT DATE:        05/24/2001|
+------------------------------------------------+EVENT TIME:        18:09[CDT]|
| NRC NOTIFIED BY:  MIKE HAUNER                  |LAST UPDATE DATE:  05/24/2001|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |SONIA BURGESS        R3      |
|10 CFR SECTION:                                 |                             |
|*IND 50.72(b)(3)(v)(D)   ACCIDENT MITIGATION    |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          Y       1        Startup          |1        Startup          |
|                                                   |                          |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| HPCI DECLARED INOPERABLE                                                     |
|                                                                              |
| "During a reactor startup following a refueling outage, HPCI was declared    |
| inoperable and is reportable under 50.72(b)(3)(v)(D) and 50.72(b)(3)(vi) as  |
| a single failure.                                                            |
|                                                                              |
| "Upon completion of HPCI system operability testing, it was discovered that  |
| the HPCI system flow controller indicated approximately 500 GPM verses an    |
| expected 0 GPM. Since the plant is in MODE 2 and reactor pressure is greater |
| than 150 PSIG, HPCI was declared inoperable and a 14-day LCO was entered per |
| TS 3.5.1, condition F.                                                       |
|                                                                              |
| "The preliminary investigation results are that air in the HPCI system flow  |
| transmitter sensing lines is causing the erroneous flow indication.          |
| Troubleshooting efforts are in progress."                                    |
|                                                                              |
| The NRC resident inspector has been informed of this event by the licensee.  |
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|General Information or Other                     |Event Number:   38030       |
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| REP ORG:  CA RADIATION CONTROL PRGM            |NOTIFICATION DATE: 05/24/2001|
|LICENSEE:  IBA/STERIGENICS INTERNATIONAL        |NOTIFICATION TIME: 23:05[EDT]|
|    CITY:  CORONA                   REGION:  4  |EVENT DATE:        04/24/2001|
|  COUNTY:                            STATE:  CA |EVENT TIME:             [PDT]|
|LICENSE#:  5956-33               AGREEMENT:  Y  |LAST UPDATE DATE:  05/24/2001|
|  DOCKET:                                       |+----------------------------+
|                                                |PERSON          ORGANIZATION |
|                                                |MARK SHAFFER         R4      |
|                                                |THOMAS ESSIG         NMSS    |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  ROBERT GREGER                |                             |
|  HQ OPS OFFICER:  BOB STRANSKY                 |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|NAGR                     AGREEMENT STATE        |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
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                                   EVENT TEXT                                   
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| AGREEMENT STATE REPORT                                                       |
|                                                                              |
| On 4/24/2001, an irradiator facility experienced a loss of electrical power  |
| to a programmable logic controller (PLC) which resulted in the inability to  |
| automatically lower the source racks. The source racks were manually lowered |
| to a safe condition upon discovery of the failure.                           |
|                                                                              |
| The following information was provided by the licensee to the California     |
| Radiation Control Program on 5/15/2001:                                      |
|                                                                              |
| "Description of Events:                                                      |
|                                                                              |
| "The first indication that there was a problem came at 9:00 p.m. 4/24/01,    |
| when the in-line water monitor signaled a failure. The Shift Leader took     |
| appropriate action per the Emergency Procedures and determined that there    |
| was no radiation present in the water system. He notified the QA Technician, |
| who had performed a calibration of the monitor that afternoon.               |
|                                                                              |
| "After reviewing the procedure followed for calibration routine and          |
| determining that no problems occurred with the calibration that would trip   |
| the alarm, the QA Technician, notified the facility Radiation Protection     |
| Office (RPO). She determined that this was a false alarm, probably caused by |
| air bubbles in the system, as has previously occurred with the water         |
| monitor. [... Permission was given] to allow the system to continue running  |
| with the water alarm disarmed until more investigation could be performed in |
| the morning.                                                                 |
|                                                                              |
| "Starting at about 7:00 a.m., additional water counts, using the monitor,    |
| were taken and resulted in normal background readings. Since the routine     |
| counts showed expected background levels and the alarm did not activate      |
| again, the concluded that a pocket of water bubbles from a filter change had |
| worked its way through the system and caused spurious readings on the        |
| monitor, which had occurred on previous occasions. All of the events to this |
| point were consistent with this determination.                               |
|                                                                              |
| "At 8:20 am., the Operator notified the RPO that the in-line alarm was       |
| sounding again. On reviewing the PLC control panel, she noted that none of   |
| the indicators on the panel were lit, as they should have been, even though  |
| the computer monitor (PLC user interface) was operating. In concert with the |
| Plant Manager, they determined that the audible alarm that the Operator      |
| heard was not the in-line monitor, but was an alarm indicating that the PLC  |
| was off-line.                                                                |
|                                                                              |
| "Further investigation revealed that the system conveyor had stopped moving  |
| (i.e., product was stationary within the cell), but that the source racks    |
| bad not automatically returned to the shielded position, as they should      |
| have, the source racks were manually lowered from the roof by 8:40 a.m.      |
| During this time, the door interlock continued to function properly,         |
| prohibiting access to the cell through the personnel access door.            |
|                                                                              |
| "In determining the probable cause of the event, the first evaluation was    |
| that the power supply had malfunctioned. However, upon further               |
| investigation, it was determined that the most probable cause was an         |
| electrical short in the system. After extensive trouble-shooting and         |
| investigation, the electrical short was finally located in the line going to |
| one of the emergency pull cords in the cell. The cable had actually melted   |
| at the point of the failure.                                                 |
|                                                                              |
| "That part of the systems was rewired and the system restarted at            |
| approximately 4:00 p.m. The safety system was checked for proper operation   |
| and routine processing resumed at 4:45 p.m.                                  |
|                                                                              |
| "Evaluation of Event and Root Cause:                                         |
|                                                                              |
| "Upon Engineering review of the electrical drawings, it was determined that  |
| a short circuit on the pull cords or other devices could have tripped one of |
| the circuit breakers, power from which feeds the PLC and other modules in    |
| the PLC rack. The audible alarm was the PLC Off Line Sonalert, which, as     |
| intended, served as a warning the PLC was not operating. With the PLC off,   |
| there was no power control to lower the source racks. In normal              |
| circumstances of power failure, the uninterruptible power supply (UPS)       |
| provides adequate emergency power to lower the source racks by releasing the |
| hoist brakes in a pulsed mode. However, with the PLC not operating, this     |
| power was not supplied to the brakes, which then had to be released          |
| manually.                                                                    |
|                                                                              |
| "The water monitor alarm activation was probably caused by shorting line     |
| voltage to the grounding circuit. This momentary surge in current,           |
| particularly on the ground path, could cause an erroneous indication at the  |
| monitor. Other facilities have had spurious water monitor alarms resulting   |
| from ground fault conditions.                                                |
|                                                                              |
| "Corrective Actions and Additional Considerations:                           |
|                                                                              |
| "Corrective actions to the event are:                                        |
|                                                                              |
| "1.     The circuit will be modified to ensure the PLC does not lose power   |
| if a device or device wiring causes a short circuit.                         |
|                                                                              |
| "2.     Additional training will be provided to operators to be more         |
| cognizant of the system response to a PLC off-line fault. While the PLC      |
| off-line alarm is a local alarm, meaning that it sounds at the control       |
| console and does not active general alarms throughout the warehouse, all     |
| system operations are stopped, including overhead conveyors and the 4-shelf  |
| elevator (i.e., device that shifts totes among positions in the carrier).    |
| The absence of movement in these systems should have alerted the operator to |
| a systemic failure of the controls. In this instance, the tune period        |
| between the equipment failure and initial resolution (manually lowering the  |
| source racks) was only a few minutes. Because the door interlock continues   |
| to function under these circumstances, the situation did not pose a          |
| radiation safety hazard to the operator or other personnel. Although,        |
| operator training currently includes instructions for determining console    |
| power status and the proper procedure for lowering the source racks under    |
| circumstances such as occurred here, the training will be reinforced and     |
| repeated                                                                     |
|                                                                              |
| "3.     To avoid further problems with the in-line water monitor alarm, an   |
| evaluation is being conducted to determine whether the water monitor can be  |
| connected to an isolated-ground receptacle and circuit. This would have the  |
| effect of making the monitor less affected by stray currents, and other      |
| sources of 'noise' on the power line."                                       |
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