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Event Notification Report for June 2, 2000

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           06/01/2000 - 06/02/2000

                              ** EVENT NUMBERS **

37046  37047  

!!!!!!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED  !!!!!!!
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|Power Reactor                                    |Event Number:   37046       |
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| FACILITY: LASALLE                  REGION:  3  |NOTIFICATION DATE: 05/31/2000|
|    UNIT:  [] [2] []                 STATE:  IL |NOTIFICATION TIME: 18:04[EDT]|
|   RXTYPE: [1] GE-5,[2] GE-5                    |EVENT DATE:        05/31/2000|
+------------------------------------------------+EVENT TIME:        13:30[CDT]|
| NRC NOTIFIED BY:  COVEYOU                      |LAST UPDATE DATE:  06/02/2000|
|  HQ OPS OFFICER:  CHAUNCEY GOULD               +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |GARY SHEAR           R3      |
|10 CFR SECTION:                                 |                             |
|AIND 50.72(b)(2)(iii)(D) ACCIDENT MITIGATION    |                             |
|NLCO                     TECH SPEC LCO A/S      |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|2     N          Y       97       Power Operation  |97       Power Operation  |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| PLANT ENTERED A 7 DAY LCO DUE TO HPCS BEING DECLARED INOPERABLE.             |
|                                                                              |
| While performing monthly surveillance start LOS-DG-M3, for the High-Pressure |
| Core Spray (HPCS) systems Emergency Diesel Generator, the Diesel             |
| automatically tripped off on an over-speed signal. The Diesel was being      |
| started from an idle condition while an operator was attempting to maintain  |
| speed between 400 and 500 rpm. The Diesel does not appear to have been       |
| damaged but remains shutdown and unavailable for on-going investigation of   |
| the failure. The High-Pressure Core Spray system is inoperable but available |
| from normal power source only. The failure mechanism is being investigated   |
| and corrective actions will be performed.                                    |
|                                                                              |
| The NRC Resident Inspector was notified.                                     |
|                                                                              |
| * * * UPDATE AT 2211 ON 06/01/00 BY SHANE MARIK TO JOLLIFFE * * *            |
|                                                                              |
|                                                                              |
| The licensee investigation has determined that the cause of the event was    |
| due to operator overcompensation of the engine governor during the start     |
| that resulted in the EDG accelerating to the overspeed setpoint and tripping |
| on overspeed.  The operator performing the slow (idle) start in accordance   |
| with the monthly Technical                                                   |
| Specification surveillance procedure was a trainee under supervision by a    |
| qualified operator.  The EDG was already inoperable for the performance of   |
| the monthly surveillance test that verifies operability of the EDG to start  |
| and carry full load for at least 60 minutes.  During inspection, no          |
| mechanical or electrical malfunctions were                                   |
| found associated with governor settings, the start circuitry, the engine     |
| fuel racks, or fuel injector linkages.  The fuel rack and associated fuel    |
| injector linkages were then verified to have freedom of movement without     |
| binding.  A subsequent fast start was performed (same as an automatic start) |
| that verified that the EDG did not have a malfunction that would cause it to |
| trip on overspeed.  The EDG would have satisfied its intended safety         |
| function when in standby (no operator interface is required for the          |
| governor/fuel rack control. except for surveillance testing).  Therefore,    |
| the overspeed trip of the High Pressure Core Spray System EDG is not         |
| reportable as a                                                              |
| condition that alone could have prevented fulfillment of a safety function.  |
|                                                                              |
| Since the failure occurred after the EDG was inoperable due to not being     |
| lined up for standby operation (removed from service as part of a planned    |
| evolution in accordance with an approved procedure), the start  was a slow   |
| start controlled by an operator and restoration of the EDG was less than 12  |
| hours and well within the 14 day Technical Specification allowed outage      |
| time.  The licensee has determined that this event is not reportable to the  |
| NRC, and desires to retract this event notification.                         |
|                                                                              |
| The licensee notified the NRC Resident Inspector.                            |
|                                                                              |
| The NRC Operations Officer notified the R3DO Bruce Jorgensen.                |
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|Fuel Cycle Facility                              |Event Number:   37047       |
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| FACILITY: PORTSMOUTH GASEOUS DIFFUSION PLANT   |NOTIFICATION DATE: 06/01/2000|
|   RXTYPE: URANIUM ENRICHMENT FACILITY          |NOTIFICATION TIME: 09:34[EDT]|
| COMMENTS: 2 DEMOCRACY CENTER                   |EVENT DATE:        05/31/2000|
|           6903 ROCKLEDGE DRIVE                 |EVENT TIME:        10:00[EDT]|
|           BETHESDA, MD 20817    (301)564-3200  |LAST UPDATE DATE:  06/01/2000|
|    CITY:  PIKETON                  REGION:  3  +-----------------------------+
|  COUNTY:  PIKE                      STATE:  OH |PERSON          ORGANIZATION |
|LICENSE#:  GDP-2                 AGREEMENT:  N  |GARY SHEAR           R3      |
|  DOCKET:  0707002                              |BRIAN SMITH          NMSS    |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  JEFF CASTLE                  |                             |
|  HQ OPS OFFICER:  JOHN MacKINNON               |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|NBNL                     RESPONSE-BULLETIN      |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
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                                   EVENT TEXT                                   
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| CATEGORY 1 AND CATEGORY 2 MATERIAL FOUND WITHIN 2 FEET OF EACH OTHER         |
|                                                                              |
| NRC Bulletin 91-01 24 hour notification                                      |
|                                                                              |
| On May 31, 2000, PORTS plant personnel discovered NCSA-PLANT048              |
| non-compliance during the monthly Nuclear Criticality Safety (NCS) walk      |
| through. Category 1 contaminated metal was discovered in close proximity     |
| (less than 2 feet) to Category 2 contaminated metal. Category 1 contaminated |
| metal is defined as items that have no visible uranium on them, items only   |
| contaminated with non-fissile radiological isotopes, items from a            |
| non-fissile material operation or items with hidden cavities from            |
| non-fissile material operations. Category 2 contaminated metal is defined as |
| an item that has a hidden cavity with potential for significant uranium      |
| material in the cavity. This was a violation of NCSA-PLANT048 requirement #  |
| 2 which states, "Category 2 contaminated metal shall not be stored in a      |
| Category 1 contaminated metal storage area". This constituted the loss of    |
| one control (spacing) of the double contingency principle. The first control |
| (that of not storing Category 2 Items with Category 1) was lost. The second  |
| control (that of categorizing the Category 1 metal Items correctly, mass     |
| control) was maintained throughout this event. This condition was corrected  |
| under NCS Engineering guidance and compliance re-established at 1205 hours.  |
|                                                                              |
| The monthly NCS walk through also identified a NCSA-PLANT048 administrative  |
| noncompliance. NCSA-PLANT048 "Contaminated Metal" requires that a sign be    |
| posted for Category 2 contaminated metal storage areas. The converters       |
| stored outside of the X-700 building meet the requirements of Category 2     |
| contaminated metal but the area was not posted. Temporary signs were posted  |
| to re-establish compliance with NCSA-PLANT048.                               |
|                                                                              |
| SAFETY SIGNIFICANCE OF EVENTS:                                               |
|                                                                              |
| This event has low safety significance. The six converters on the west side  |
| of X-700 contain less than a safe mass at the indicated enrichment. There    |
| were no visible uranium compounds on the Category 1 contaminated metal that  |
| was stored In close proximity to the converters. Since there was no visible  |
| uranium on the Category 1 metal, there was no additional risk of a           |
| criticality occurring. NCSE-PLANT048.E04 documents that Category 1           |
| contaminated metal can have at most 24.2 grams 235U per 2,500 square feet of |
| metal surface.  In no case was more than 2500 square feet of Category 1      |
| material found within 2 feet of the six converters.                          |
|                                                                              |
| NDA results indicate (with uncertainty applied) that the largest amount of   |
| 235U in one converter is 1099 grams at an enrichment of 2.3 wt% 235U in the  |
| form of UO2F2. At 3 wt% 235U, the estimated minimum critical mass is 3,077   |
| grams 235U and the safe mass is 1180 grams of 235U. Assuming 25 additional   |
| grams of 235U due to the presence of the Category 1 metal, the total amount  |
| of 235U (1124 grams 235U) is still below a safe mass, for the converter unit |
| with the highest loading.                                                    |
|                                                                              |
| POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO[S] OF HOW            |
| CRITICALITY COULD OCCUR):                                                    |
|                                                                              |
| A 'dirty' metal item classified as Category 1 with the 'dirt' containing a   |
| large amount of enriched uranium stored with a Category 2 item such that the |
| total uranium present exceeds a critical mass and is in the proper geometry  |
| for a criticality to occur                                                   |
|                                                                              |
| CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.):     |
|                                                                              |
| The controlled parameters are the segregation (proper spacing) of Category 1 |
| and 2 storage areas and the proper classification of the Category 1          |
| contaminated metal items (mass control).                                     |
|                                                                              |
| ESTIMATED AMOUNT, ENRICHMENT. FORM OF LICENSED MATERIAL (INCLUDE PROCESS     |
| LIMIT AND % WORST CASE OF CRITICAL MASS):                                    |
|                                                                              |
| NDA results indicate (with uncertainty applied) that the largest amount of   |
| 235U in one converter is 1099 grams at an enrichment of 2.3 wt% 235U in the  |
| form of UO2F2.  At 3 wt% 235U, the estimated minimum critical mass is 3,077  |
| grams 235U due to the presence of the Category 1 metal, the total amount of  |
| 235U (1124 grams 235U) is still below a safe mass, for the converter unit    |
| with the highest loading.                                                    |
|                                                                              |
| NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION   |
| OF THE FAILURES OR DEFICIENCIES:                                             |
|                                                                              |
| The first control that of not storing Category 2 items with Category 1 Items |
| (spacing) was lost. The second control, that of categorizing the Category 1  |
| metal items was done correctly (mass control). The Category 1 items were     |
| observed to have no visible uranium on them. Thus, the first control was     |
| lost but the second control of categorizing the Category 1 contaminated      |
| metal items was done correctly. This resulted in a lost on one control       |
| (spacing) relied on for double contingency.                                  |
|                                                                              |
| CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEM AND WHEN EACH WAS IMPLEMENTED:   |
|                                                                              |
| At 1205 hours, under NCS engineering guidance, the Category 1 contaminated   |
| metal was spaced at least 2 feet from all Category 2 contaminated metal      |
| (converters). Signs were posted identifying the Category 2 contaminated      |
| metal storage area.                                                          |
|                                                                              |
| The NRC Resident Inspector was notified of this event by the certificate     |
| holder.                                                                      |
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