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Event Notification Report for July 25, 2001

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           07/24/2001 - 07/25/2001

                              ** EVENT NUMBERS **

38164  38165  38167  38168  

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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     |
|                                                   |                          |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| 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     |
| ongoing.                                                                     |
|                                                                              |
| 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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|Power Reactor                                    |Event Number:   38165       |
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| FACILITY: ARKANSAS NUCLEAR         REGION:  4  |NOTIFICATION DATE: 07/24/2001|
|    UNIT:  [1] [] []                 STATE:  AR |NOTIFICATION TIME: 10:00[EDT]|
|   RXTYPE: [1] B&W-L-LP,[2] CE                  |EVENT DATE:        07/24/2001|
+------------------------------------------------+EVENT TIME:        06:39[CDT]|
| NRC NOTIFIED BY:  PATRICK WILLIAMS             |LAST UPDATE DATE:  07/24/2001|
|  HQ OPS OFFICER:  FANGIE JONES                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          NON EMERGENCY         |GARY SANBORN         R4      |
|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     N          Y       100      Power Operation  |0        Hot Standby      |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| AUTOMATIC REACTOR TRIP ON HIGH REACTOR COOLANT SYSTEM PRESSURE               |
|                                                                              |
| The unit received an automatic reactor trip on high reactor coolant system   |
| pressure due to a problem with the main turbine control valves.  There were  |
| no ESF actuations and all rods fully inserted.  Steam generator safeties     |
| opened for a short period as expected.  The plant is stable in hot shutdown  |
| with excess heat being controlled by condenser bypass valves with main       |
| feedwater system controlling steam generator level.                          |
|                                                                              |
| The problem is being investigated and the cause is unknown at this time.     |
|                                                                              |
| The licensee notified the NRC Resident Inspector and state agencies.         |
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|Power Reactor                                    |Event Number:   38167       |
+------------------------------------------------------------------------------+
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| FACILITY: SEABROOK                 REGION:  1  |NOTIFICATION DATE: 07/24/2001|
|    UNIT:  [1] [] []                 STATE:  NH |NOTIFICATION TIME: 17:35[EDT]|
|   RXTYPE: [1] W-4-LP                           |EVENT DATE:        07/24/2001|
+------------------------------------------------+EVENT TIME:        15:50[EDT]|
| NRC NOTIFIED BY:  HUGH HAWKINS                 |LAST UPDATE DATE:  07/24/2001|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          NON EMERGENCY         |JOHN WHITE           R1      |
|10 CFR SECTION:                                 |                             |
|APRE 50.72(b)(2)(xi)     OFFSITE NOTIFICATION   |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| OFFSITE NOTIFICATION DUE TO EXCEEDING NPDES PERMIT LIMITS                    |
|                                                                              |
| "The EPA and NH Department of Environmental Services (NHDES) were notified   |
| this afternoon of a daily maximum exceedence of the NPDES Permit limit for   |
| oil and grease at Outfall 025 (Waste Test Tank). The discharge occurred on   |
| July 3, 2001. The amount of the exceedence is minor but the significance is  |
| still being evaluated so this report is being made as a conservative         |
| decision."                                                                   |
|                                                                              |
| The NRC resident inspector has been informed of this notification by the     |
| licensee.                                                                    |
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|Fuel Cycle Facility                              |Event Number:   38168       |
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| FACILITY: PORTSMOUTH GASEOUS DIFFUSION PLANT   |NOTIFICATION DATE: 07/25/2001|
|   RXTYPE: URANIUM ENRICHMENT FACILITY          |NOTIFICATION TIME: 05:28[EDT]|
| COMMENTS: 2 DEMOCRACY CENTER                   |EVENT DATE:        07/24/2001|
|           6903 ROCKLEDGE DRIVE                 |EVENT TIME:        12:30[EDT]|
|           BETHESDA, MD 20817    (301)564-3200  |LAST UPDATE DATE:  07/25/2001|
|    CITY:  PIKETON                  REGION:  3  +-----------------------------+
|  COUNTY:  PIKE                      STATE:  OH |PERSON          ORGANIZATION |
|LICENSE#:  GDP-2                 AGREEMENT:  N  |PATRICK HILAND       R3      |
|  DOCKET:  0707002                              |C.W. (BILL) REAMER   NMSS    |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  SISLER                       |                             |
|  HQ OPS OFFICER:  CHAUNCEY GOULD               |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          NON EMERGENCY         |                             |
|10 CFR SECTION:                                 |                             |
|NBNL                     RESPONSE-BULLETIN      |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
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                                   EVENT TEXT                                   
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| 24 - HOUR 91-01 BULLETIN - LOSS OF ONE CONTROL OF THE DOUBLE CONTINGENCY     |
| PRINCIPLE                                                                    |
|                                                                              |
| On 7-24-01 at 1230 hours, a process operator in the X-330 Building           |
| discovered a NCSA-0330_004.A05 noncompliance with cell 29-4-6.  Cell 29-4-6  |
| is a shutdown cell at a UF6 negative and was buffered above 14 psia.  Over   |
| time the pressure decrease to 13.96 psia.  This violated NCSA-0330_004.A05   |
| requirement #8 resulting in a loss of one control (moderation) of the double |
| contingency principle.  Mass (second control) was maintained throughout the  |
| event.                                                                       |
|                                                                              |
| NCSA-0330_004.A05 requirement #8 states in part, "Within 8 hours after       |
| cascade equipment shutdown (motor turned off) and with the system at a UF6   |
| negative, the system shall be pressurized with plant air or N2 buffer at >   |
| 14 psia, unless the equipment is undergoing maintenance, pre and post        |
| maintenance troubleshooting, being evacuated or treated."                    |
|                                                                              |
| Buffer pressure was increased to greater than 14 psia at 1300 hours.         |
| Moderation control was re-established for cell 29-4-6.                       |
|                                                                              |
| The safety significance of this event is low. There is no deposit in this    |
| cell.  The worst case would be contamination on process surfaces exposed to  |
| process gas prior to shutdown and buffering.                                 |
|                                                                              |
| This event is reportable per NRC BL 91-01 as a loss of one control of the    |
| double contingency principle.                                                |
|                                                                              |
| SAFETY SIGNIFICANCE OF EVENTS:                                               |
|                                                                              |
| The safety significance of this event is low.  There is no deposit in the    |
| cell (thus is less than a safe mass for an H/U=4 and the cell is isolated    |
| from the cascade.  The mass in the cell is controlled by virtue of the fact  |
| that the shutdown cell is isolated from the cascade which is also shutdown.  |
| If the unbuffered condition were permitted to continue for a long period of  |
| time, the H/U could eventually reach a maximum of 4.  However, since any     |
| material in the cell is less than the safe mass H/U ratio, a criticality     |
| would not occur even if the H/U reached the maximum through the loss of a    |
| buffer.                                                                      |
|                                                                              |
| POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO(S) OF HOW            |
| CRITICALITY COULD OCCUR):                                                    |
|                                                                              |
| The cell would need to be unisolated and UF6 introduced to create a deposit. |
| That deposit would then have to become sufficiently moderated in order for a |
| criticality to occur.                                                        |
|                                                                              |
| CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.):     |
|                                                                              |
| The parameters controlled are mass and moderation.                           |
|                                                                              |
| ESTIMATED AMOUNT,  ENRICHMENT,  FORM OF LICENSED MATERIAL (INCLUDE PROCESS   |
| LIMIT AND % WORST CASE OF CRITICAL MASS):                                    |
|                                                                              |
| There is no deposit in this cell.  Worst case would be contamination on      |
| process surfaces exposed to process gas prior to shutdown and buffering.     |
|                                                                              |
| NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION   |
| OF THE FAILURES OR DEFICIENCIES                                              |
|                                                                              |
| The NCS control is a dry air buffer >14 psia.  Over time the pressure        |
| decreased to 13.96 psia.                                                     |
|                                                                              |
| CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEM AND WHEN EACH WAS IMPLEMENTED:   |
|                                                                              |
| Buffer pressure was increased to greater than 14 psia at 1300 hours.         |
| Control was re-established.                                                  |
|                                                                              |
| The NRC Resident Inspector was notified along with the DOE Representative.   |
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