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Event Notification Report for July 24, 2001

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           07/23/2001 - 07/24/2001

                              ** EVENT NUMBERS **

38161  38162  38163  38164  

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|Fuel Cycle Facility                              |Event Number:   38161       |
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| FACILITY: PADUCAH GASEOUS DIFFUSION PLANT      |NOTIFICATION DATE: 07/23/2001|
|   RXTYPE: URANIUM ENRICHMENT FACILITY          |NOTIFICATION TIME: 17:27[EDT]|
| COMMENTS: 2 DEMOCRACY CENTER                   |EVENT DATE:        07/23/2001|
|           6903 ROCKLEDGE DRIVE                 |EVENT TIME:        12:55[CDT]|
|           BETHESDA, MD 20817    (301)564-3200  |LAST UPDATE DATE:  07/23/2001|
|    CITY:  PADUCAH                  REGION:  3  +-----------------------------+
|  COUNTY:  McCRACKEN                 STATE:  KY |PERSON          ORGANIZATION |
|LICENSE#:  GDP-1                 AGREEMENT:  Y  |MONTE PHILLIPS       R3      |
|  DOCKET:  0707001                              |C.W. (BILL) REAMER   NMSS    |
+------------------------------------------------+NADER MAMISH         IRO     |
| NRC NOTIFIED BY:  TOM WHITE                    |                             |
|  HQ OPS OFFICER:  BOB STRANSKY                 |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          NON EMERGENCY         |                             |
|10 CFR SECTION:                                 |                             |
|NBNL                     RESPONSE-BULLETIN      |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
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                                   EVENT TEXT                                   
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| 4-HOUR NRC BULLETIN 91-01 REPORT                                             |
|                                                                              |
| The following text is a portion of a facsimile received from Paducah         |
| personnel:                                                                   |
|                                                                              |
| "At 1255, on 7-23-01, the Plant Shift Superintendent (PSS) was notified that |
| checks required to meet the requirements of NCSA CAS-011 were not performed  |
| during replacement of the C-337 Unit 5 Cell 10 RCW [recirculating cooling    |
| water] spool piece. NCSA CAS-011 requires a line clarity check on the peak   |
| reading pressure gauges prior to connecting the spool piece. This check was  |
| not performed. The purpose of this requirement is to ensure the RCW pressure |
| in the condenser does not exceed 35.5 PSIA.                                  |
|                                                                              |
| "The NRC Acting Senior Resident has been notified of this event.             |
|                                                                              |
| "SAFETY SIGNIFICANCE OF EVENTS:                                              |
| "While a control was violated, insufficient time existed for moisture from   |
| the RCW system to enter the process gas system.                              |
|                                                                              |
| "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 RCW 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. The process gas equipment must        |
| 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 corner 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 a moderation of the deposit.                                           |
|                                                                              |
| "CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC):     |
| "Two controls on moderation.                                                 |
|                                                                              |
| "ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL (INCLUDE PROCESS    |
| LIMIT AND % WORST CASE CRITICAL MASS):                                       |
| "No known deposits of concern at this time..                                 |
|                                                                              |
| "NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION  |
| OF THE FAILURES OR DEFICIENCIES:                                             |
| "Double contingency for this scenario is established by implementing two     |
| controls on moderation.                                                      |
|                                                                              |
| "The first leg of double contingency is based on preventing moderation of a  |
| deposit by maintaining the RCW pressure in a condenser below 35.5 PSIA.      |
| Pressure gauges are installed and checked for clarity whenever the RCW       |
| return valve is closed on a cell without a fluorinating environment. Since   |
| clarity of the pressure reading instrument was not verified, the             |
| functionality of the pressure reading instrument cannot be assured,          |
| violating the control.                                                       |
|                                                                              |
| "The second leg of double contingency is based upon independent verification |
| that the RCW pressure gauges are reading correctly. Since clarity of the     |
| pressure reading instrument was not independently verified, this control was |
| violated.                                                                    |
|                                                                              |
| "CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEMS AND WHEN EACH WAS              |
| IMPLEMENTED:                                                                 |
| "Upon discovery of the failure to perform the requirement, the coolant       |
| system was sampled for moisture and verified to be dry."                     |
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|Power Reactor                                    |Event Number:   38162       |
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| FACILITY: SEABROOK                 REGION:  1  |NOTIFICATION DATE: 07/23/2001|
|    UNIT:  [1] [] []                 STATE:  NH |NOTIFICATION TIME: 18:34[EDT]|
|   RXTYPE: [1] W-4-LP                           |EVENT DATE:        07/23/2001|
+------------------------------------------------+EVENT TIME:        17:45[EDT]|
| NRC NOTIFIED BY:  HUGH HAWKINS                 |LAST UPDATE DATE:  07/23/2001|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          NON EMERGENCY         |JOHN WHITE           R1      |
|10 CFR SECTION:                                 |                             |
|DDDD 73.71               UNSPECIFIED PARAGRAPH  |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| SECURITY REPORT                                                              |
|                                                                              |
| Unescorted access granted inappropriately. Immediate compensatory measures   |
| taken upon discovery. The NRC resident inspector will be informed. Contact   |
| the NRC Operations Center for additional details.                            |
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|Power Reactor                                    |Event Number:   38163       |
+------------------------------------------------------------------------------+
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| FACILITY: HATCH                    REGION:  2  |NOTIFICATION DATE: 07/23/2001|
|    UNIT:  [1] [2] []                STATE:  GA |NOTIFICATION TIME: 22:19[EDT]|
|   RXTYPE: [1] GE-4,[2] GE-4                    |EVENT DATE:        07/23/2001|
+------------------------------------------------+EVENT TIME:        21:36[EDT]|
| NRC NOTIFIED BY:  STEVE HOWARD                 |LAST UPDATE DATE:  07/23/2001|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          UNUSUAL EVENT         |JAY HENSON           R2      |
|10 CFR SECTION:                                 |WILLIAM DEAN         NRR     |
|AAEC 50.72(a) (1) (i)    EMERGENCY DECLARED     |MR. EACHES           FEMA    |
|                                                |NADER MAMISH         IRO     |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          Y       100      Power Operation  |85       Power Operation  |
|2     N          Y       100      Power Operation  |90       Power Operation  |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| UNUSUAL EVENT DECLARED DUE TO LOW SERVICE WATER INTAKE LEVEL                 |
|                                                                              |
| At 2136, the licensee declared an Unusual Event due to service water intake  |
| pump well level less than 60.7' MSL (mean sea level). The licensee           |
| determined that one of the intake traveling water screens had become clogged |
| with debris, cleared the screen, and terminated the UE at 2137 when normal   |
| pump well level was restored. Reactor power of both units was reduced as a   |
| result of the event.                                                         |
|                                                                              |
| The licensee's preliminary investigation indicates that the upstream         |
| traveling water screen did not automatically enter a backwash cycle as       |
| designed in response to increased differential pressure. The downstream      |
| screen was tagged out of service for a planned design modification. The NRC  |
| resident inspector has been informed of this event by the licensee.          |
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|Power Reactor                                    |Event Number:   38164       |
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| FACILITY: CLINTON                  REGION:  3  |NOTIFICATION DATE: 07/24/2001|
|    UNIT:  [1] [] []                 STATE:  IL |NOTIFICATION TIME: 05:59[EDT]|
|   RXTYPE: [1] GE-6                             |EVENT DATE:        07/24/2001|
+------------------------------------------------+EVENT TIME:        02:51[CDT]|
| NRC NOTIFIED BY:  LARRY WESTEROOK              |LAST UPDATE DATE:  07/24/2001|
|  HQ OPS OFFICER:  FANGIE JONES                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          NON EMERGENCY         |MONTE PHILLIPS       R3      |
|10 CFR SECTION:                                 |                             |
|ARPS 50.72(b)(2)(iv)(B)  RPS ACTUATION - CRITICA|                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     A/R        Y       100      Power Operation  |0        Hot Shutdown     |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| AUTOMATIC REACTOR SCRAM ON HIGH REACTOR VESSEL LEVEL                         |
|                                                                              |
| The reactor scrammed at 0251 CDT on 7/24/20001 on a level 8 signal, a high   |
| reactor vessel level.  All rods fully inserted and all systems functioned    |
| properly.  At the time of the scram there was a surveillance being performed |
| on a level transmitter that feeds the feedwater level control system.        |
| Exactly what happened is not known at this time, but an investigation is on  |
| going.                                                                       |
|                                                                              |
| The plant is stable using the bypass valves to the condenser and level is    |
| being maintained with motor driven feedwater pump.                           |
|                                                                              |
| The licensee notified the NRC Resident Inspector.                            |
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