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Event Notification Report for August 22, 2001

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           08/21/2001 - 08/22/2001

                              ** EVENT NUMBERS **

37999  38224  

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|Fuel Cycle Facility                              |Event Number:   37999       |
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| FACILITY: PADUCAH GASEOUS DIFFUSION PLANT      |NOTIFICATION DATE: 05/16/2001|
|   RXTYPE: URANIUM ENRICHMENT FACILITY          |NOTIFICATION TIME: 23:53[EDT]|
| COMMENTS: 2 DEMOCRACY CENTER                   |EVENT DATE:        05/16/2001|
|           6903 ROCKLEDGE DRIVE                 |EVENT TIME:        19:00[CDT]|
|           BETHESDA, MD 20817    (301)564-3200  |LAST UPDATE DATE:  08/21/2001|
|    CITY:  PADUCAH                  REGION:  3  +-----------------------------+
|  COUNTY:  McCRACKEN                 STATE:  KY |PERSON          ORGANIZATION |
|LICENSE#:  GDP-1                 AGREEMENT:  Y  |MICHAEL PARKER       R3      |
|  DOCKET:  0707001                              |JOHN GREEVES         NMSS    |
+------------------------------------------------+NADER MAMISH         IRO     |
| NRC NOTIFIED BY:  KEVIN BEASLEY                |                             |
|  HQ OPS OFFICER:  DOUG WEAVER                  |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          NON EMERGENCY         |                             |
|10 CFR SECTION:                                 |                             |
|NBNL                     RESPONSE-BULLETIN      |                             |
|                                                |                             |
|                                                |                             |
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|                                                |                             |
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                                   EVENT TEXT                                   
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| NRC BULLETIN 91-01 RESPONSE - CRITICALITY CONTROL - (4-Hour Report)          |
|                                                                              |
| During the revision to NCSE 052 and 039, it was discovered that the          |
| condenser could potentially be pressurized greater than 35.5 psia when the   |
| condenser supply and return valve are both closed without a fluorinating     |
| environment in the process gas system.   NCSA CAS-002/011 allow both the     |
| supply and return valves to be closed when draining the condenser without a  |
| fluorinating environment.  NCSEs 052 and 039 rely on the condenser supply    |
| valve to be closed enough to prevent the condenser from being pressurized    |
| above 35.5 psia during the time the return valve is closed and maintenance   |
| personnel relieve the pressure on the condenser.   Based on recent           |
| discussions, it was discovered that closure of the supply valve may not      |
| provide sufficient isolation to prevent the condenser from being pressurized |
| above 35.5 psia with the return valve closed because of potential seat       |
| leakage of the supply valve.                                                 |
|                                                                              |
| The licensee has stopped all maintenance activities which could create this  |
| condition.  Also, samples will be taken where this maintenance has occurred  |
| to check that the freon still complies with the water content limits.        |
|                                                                              |
| Paducah personnel notified the NRC resident inspector.                       |
|                                                                              |
| ***** UPDATE RECEIVED AT 1500 EDT ON 06/21/01 FROM CALVIN PITTMAN TO LEIGH   |
| TROCINE *****                                                                |
|                                                                              |
| The following text is a portion of a facsimile received from Paducah         |
| personnel:                                                                   |
|                                                                              |
| "At 1900 [CDT] on [05/16/01], the Plant Shift Superintendent (PSS) was       |
| notified of a deficient Nuclear Criticality Safety Evaluation.  NCSAs CAS    |
| 002 and CAS 011 allow both the Recirculating Cooling Water (RCW) supply and  |
| return valves to be closed when draining the R-114 condenser without a       |
| fluorinating environment.  The NCS evaluations rely on the RCW supply valve  |
| to be closed enough to prevent the condenser from being pressurized above    |
| 35.5 psia during the time the RCW return valve is closed and maintenance     |
| relieves the pressure on the condenser.  Based on recent discussions between |
| NCS and maintenance personnel, it was discovered that closure of the RCW     |
| supply valve might not provide sufficient isolation to prevent the condenser |
| from being pressurized above 35.5 psia with the return valve closed.  The    |
| RCW system provides cooling water to the R-114 condenser, which removes heat |
| from the freon system.  The freon is used to remove the heat of compression  |
| from the process gas system.  The R-114 pressure is maintained above the RCW |
| pressure to form a barrier between the process gas and the RCW cooling       |
| water, thus preventing moderation from occurring should a leak in the        |
| condenser occur.  If the RCW pressure is allowed to rise above 35.5 psia,    |
| the potential exists that the RCW pressure could exceed that of the R-114    |
| pressure.  At this point, an actual condition of RCW pressure greater than   |
| 35.5 psia has not been identified."                                          |
|                                                                              |
| "UPDATE [on 06/20/01] ATRC 01-3248:  During the Engineering review to        |
| determine permanent corrective actions, additional immediate corrective      |
| actions have become necessary.  It has been determined that when the         |
| condenser return valve is open, condenser pressure can also be affected when |
| the return header alignment is changed (i.e., closure of RCW loop isolation  |
| valves, RCW building header valves, cooling tower riser valves, etc.).       |
| Controls have been implemented to ensure that changes to the RCW system do   |
| not impact our ability to maintain R-114 pressure above RCW pressure."       |
|                                                                              |
| "SAFETY SIGNIFICANCE OF EVENTS:  The controls credited for the isolation of  |
| the condenser to ensure the pressure at the condenser does not exceed 35.5   |
| psia do not meet the intent of the NCSE for isolation.  Therefore, the NCSE  |
| analysis is deficient and double contingency is not maintained.  However,    |
| the probability for a criticality is unlikely due to the number of           |
| conditions that must be met in order for a criticality to be possible."      |
|                                                                              |
| "POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO(S) OF HOW           |
| CRITICALITY COULD OCCUR):  In order for a criticality to be possible, the    |
| following conditions must exist.  With the condenser supply and return       |
| valves closed, the supply or return valve must be leaking to allow the       |
| condenser pressure to exceed the minimum coolant pressure of 35.5 psia.      |
| With the configuration of the supply valve closed and the return valve       |
| opened, the RCW return system must be changed (i.e. closure of loop          |
| isolation valves, RCW building header valves, cooling tower riser valves,    |
| etc.) enough that the affected condenser pressure increased greater than     |
| 35.5 psia.  The process gas equipment must be at a UF6 negative and contain  |
| a UO2F2 deposit greater than a critical mass.  The condenser must have a     |
| leak of sufficient rate and duration to allow enough water to overcome the   |
| down comer allowing liquid water to enter the cooler.  The cooler must also  |
| have a simultaneous leak, which would allow wet coolant to leak into the     |
| process gas side of the equipment at a location, which would allow           |
| moderation of the deposit."                                                  |
|                                                                              |
| "CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.):    |
| Double contingency for this scenario is established by implementing two      |
| controls for moderation."                                                    |
|                                                                              |
| "ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL (INCLUDE PROCESS    |
| LIMIT AND % WORST CASE CRITICAL MASS):  Maximum assay of 5.5 wt. % U235"     |
|                                                                              |
| "NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION  |
| OF THE FAILURES OR DEFICIENCIES:  The first leg of [the] double contingency  |
| is based on isolation of the RCW condenser by closing the supply valve to    |
| maintain the condenser pressure less than 35.5 psia.  Based on discussions   |
| with maintenance personnel, the current leak rates of the supply valve may   |
| be greater than the amount assumed to ensure the condenser pressure does not |
| exceed 35.5 psia when the return valve is closed.  Also, when the return     |
| valve is open, the RCW return system could be changed (i.e., closure of loop |
| isolation valve, RCW building header valves, cooling tower riser valves,     |
| etc.).  Therefore, the intent of this control has not been met, and this leg |
| of double contingency was not maintained."                                   |
|                                                                              |
| "The second leg of [the] double contingency is based on the independent      |
| verification of the isolation of the supply valve and when the return valve  |
| is required to be open, verification that the return valve is open.  Since   |
| adequate isolation of the supply valve cannot be ensured based on            |
| verification of supply valve closure or return valve open, when required,    |
| the intent of this independent verification control was not met.  Therefore, |
| this leg of double contingency was not maintained."                          |
|                                                                              |
| "Since isolation of the RCW condenser with the supply valve closed and the   |
| return valve closed or opened may not meet the intent of the isolation       |
| requirement to maintain the condenser pressure less than 35.5 psia, these    |
| controls are deficient and double contingency has not been maintained."      |
|                                                                              |
| "CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEMS AND WHEN EACH WAS IMPLEMENTED: |
| Until the NCSEs and NCSAs can be revised and additional controls             |
| established:"                                                                |
|                                                                              |
| "Condenser Return Valve Closed"                                              |
|                                                                              |
| "1.  All maintenance activities related to closing the condenser return      |
| valve on a system, which is at a UF6 negative, have been stopped.  This does |
| not apply to systems that are not connected to the supply line or the C-310  |
| TOPS Boosters."                                                              |
|                                                                              |
| "2.  The coolant systems for condensers, which had the return valve closed   |
| without a fluorinating environment present, will be sampled in accordance    |
| with NCSA CAS-002 to verify the CFC-114 still complies with the water        |
| content limits."                                                             |
|                                                                              |
| "3.  The return [valves] on condensers, which currently have the return      |
| valve closed, fluorinating environment removed (at a UF6 negative), and is   |
| connected to the supply line, will be opened."                               |
|                                                                              |
| "RCW Building Return System (based on ATRC-01-3248)"                         |
|                                                                              |
| "4.  The plant power level will be maintained below 400 MW until NCSE        |
| changes are completed and/or necessary controls are implemented or specific  |
| evolutions are evaluated by NCS and approval is given."                      |
|                                                                              |
| "5.  Both building RCW return header valves to a given header will not be    |
| closed."                                                                     |
|                                                                              |
| "6.  At least 3 cooling tower risers for every large pump and 2 risers for   |
| every small pump will be kept in service."                                   |
|                                                                              |
| "7.  Respective building RCW bypasses will be closed before isolating an RCW |
| system loop."                                                                |
|                                                                              |
| "8.  For any auxiliary systems not protected by a delta P alarm (i.e., A-310 |
| Booster, A-335 Booster, C-337 B Booster) except the C-310 TOPS Booster, any  |
| activity that requires verification that the condenser return valve is open  |
| will also verify other valves in the return path to the applicable RCW       |
| return header are also open."                                                |
|                                                                              |
| Paducah personnel notified the NRC resident inspector.  The NRC operations   |
| officer notified the R3DO (Bruce Jorgensen) and NMSS EO (Patricia            |
| Holahan).]                                                                   |
|                                                                              |
| * * * UPDATE 1705EDT ON 8/21/01 FROM CALVIN PITTMAN TO S. SANDIN * * *       |
|                                                                              |
| The following information was provided as an update:                         |
|                                                                              |
| "The plant has completed and approved a USQD [Unreviewed Safety Question     |
| Determination] to allow the plant power level to be increased to 850 MW."    |
|                                                                              |
| The NRC resident inspector has been informed.  Notified R3DO(Gardner) and    |
| NMSS(Essig).                                                                 |
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|Hospital                                         |Event Number:   38224       |
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| REP ORG:  WYOMING MEDICAL CENTER               |NOTIFICATION DATE: 08/21/2001|
|LICENSEE:  WYOMING MEDICAL CENTER               |NOTIFICATION TIME: 15:56[EDT]|
|    CITY:  CASPER                   REGION:  4  |EVENT DATE:        08/20/2001|
|  COUNTY:  NATRONA                   STATE:  WY |EVENT TIME:        11:00[MDT]|
|LICENSE#:  49-00152-02           AGREEMENT:  N  |LAST UPDATE DATE:  08/21/2001|
|  DOCKET:                                       |+----------------------------+
|                                                |PERSON          ORGANIZATION |
|                                                |BILL JONES           R4      |
|                                                |BRIAN SMITH          NMSS    |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  THOMAS A. CHEREWICK          |                             |
|  HQ OPS OFFICER:  STEVE SANDIN                 |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          NON EMERGENCY         |                             |
|10 CFR SECTION:                                 |                             |
|LADM 35.33(a)            MED MISADMINISTRATION  |                             |
|                                                |                             |
|                                                |                             |
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                                   EVENT TEXT                                   
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| MEDICAL MISADMINISTRATION INVOLVING AN UNDERDOSE DUE TO PERSONNEL ERROR      |
|                                                                              |
| On July 10, 2001 and elderly female patient received approximately 250       |
| instead of the 500 centigray prescribed as a boost dose for urinary cancer.  |
| The device involved was a Wang applicator 3 centimeter in diameter with a    |
| hemispherical head containing a Cs-137 source.  This was an adjunct          |
| procedure to surgery.  The patient will be informed and there is no remedial |
| treatment necessary or planned.  The licensee discovered this error on       |
| 8/20/01 in a review while planning similar treatment for another patient.    |
| The following actions have been taken to preclude recurrence: all point dose |
| calculations done by hand will include the dose prescription point and a     |
| planned treatment will include a review of previous treatments utilizing     |
| this particular applicator.  The licensee attributes the underdose to        |
| personnel error and has discussed this report with the NRC Region 4 office   |
| (Whitten).                                                                   |
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