Event Notification Report for March 28, 2000

AGREEMENT STATE REPORT - STOLEN / RECOVERED TROXLER NUCLEAR GAUGE IN ARLINGTON, TX

Texas Licensee #TX-L-05082, Fugro-McClelland (Southwest), Inc., Fort Worth, Texas, reported to Texas Department of Health, Bureau of Radiation Control, the theft of a nuclear gauge from it's unsecured transport box sitting near a work site at the General Motors Plant in Arlington, Texas. The gauge was unsecured and the source rod was not locked, as the operator was going to use the gauge after a short discussion approximately 100 feet from the transport box. Gauge Manufacturer: Troxler, Model: 3411-B, Serial Number: 10390. Two sealed sources: 1) Cs-137 with nominal activity of 10 millicuries and 2) Am-241/Be, nominal activity 40 millicuries. The stolen gauge was discovered along a local street several blocks from the GM Plant and in a damaged condition - the source rod was extended and broken. The gauge was recovered by a passerby who thought the damaged gauge may be of value and took it to a local equipment rental facility to ascertain the value. He was warned of the radiation hazard but reportedly departed the facility with the broken gauge. He evidently changed his mind and notified the City of Arlington, who arrived and recovered the gauge. The gauge was turned over to the Troxler Service Facility in Arlington where a leak test was performed and indicated that the sealed sources were still intact. However, the gauge would require repair before being placed back into service. The Texas Licensee was notified of the recovery. The gauge is being maintained by the Troxler facility until release by this agency for repairs.

PRIMARY COMPONENT COOLING WATER SYSTEM INOPERABLE DUE TO THE AREA VENTILATION SYSTEM INCAPABLE OF PERFORMING ITS SAFETY FUNCTION

"On 03/26/00 Seabrook Station entered Tech Spec (TS) 3.0.3 due to both trains of the Primary Component Cooling Water (PCCW) system being declared inoperable. Both trains of PCCW were declared inoperable because the PCCW Area Ventilation System was determined to be incapable of performing its intended function.

"The PCCW system is a two train closed loop cooling system used to remove heat from plant components during plant operation, plant cooldown and during various phases of an accident. The PCCW pumps are located within the Primary Auxiliary Building (PAB). The operation of the PCCW pumps is supported by the PCCW Area Ventilation system. This ventilation system has redundant, automatically controlled auxiliary supply fans and associated dampers to ensure that the temperature in this area does not exceed design limits should the normal PAB ventilation system fail.

"During surveillance testing of the PCCW Area Ventilation system, an exhaust damper (PAH-DP-357) failed to open as required. During a subsequent local investigation by the Shift Manager and Unit Supervisor it was determined that recent painting activities may have affected both PAB Exhaust Dampers (PAH-DP-357 and PAH-DP-358). A subsequent test of PAH-DP-358 indicated that it also failed to open as required. TS 3.0.3 was entered on 03/26/00 at 0346. TS 3.0.3 was subsequently exited at 0425 on 03/26/00 after plant personnel reestablished operability for PAH-DP-358. The subject dampers automatically open to provide an exhaust flow path for the PCCW Pump Area ventilation system which supports operation of the PCCW pumps. An initial review of this condition concluded that a report pursuant to the requirements of 10CFR50.72 was not required. A subsequent review of this event determined that it is reportable pursuant to the requirements of 10CFR50.72(b)(2)(iii) as a condition that alone could have prevented the fulfillment of a safety function."

The licensee will inform the NRC resident inspector.

HOO Note: The event time was the time the licensee determined this condition to be reportable to the NRC.

* * * RETRACTION ON 04/21/00 AT 1330 HOURS BY M. KILEY TAKEN BY MACKINNON * * *

Upon further Engineering review, North Atlantic has determined that the PCCW system remained capable of performing its intended function during the period when the PAB Exhaust Dampers (PAH-DP-357 and PAH-DP-358) were painted between March 12, 2000 and March 26, 2000 when the condition was corrected. North Atlantic analyzed the area heat-up conditions as they pertain to the operation of the PCCW system and other associated safety-related equipment and concluded that the PCCW system would have performed its intended function even with the subject dampers isolated. Therefore, this condition is not reportable pursuant to the requirement of 10 CFR 50.72(b)(2)(iii) as a condition that alone could have prevented the fulfillment of a safety function. R1DO (John White) notified.

The NRC Resident Inspector has been notified of this retraction by the licensee.

NRC BULLETIN 91-01, 4 HOUR REPORT -

At 1030 on 03/28/00, a box containing uranium oxide standard vials was discovered under a workbench in building X-710 room 117, The applicable Nuclear Criticality Safety Approval/Evaluation (NCSA/E-0710-011) does not analyze storing uranium oxide vials in this area of the X-710 building. The uranium oxide vials were transported to an area designated for storage of such materials under applicable approved NCSAs. The material was non-destructive assay (NDA) tested. The combined mass of all of the uranium oxides in all the standard vials was 18 +/- 9 grams U-235 with an average enrichment of 18 wt% U-235,

SAFETY SIGNIFICANCE OF EVENTS:
The uranium oxide vials were stored at least two feet edge-to-edge from any other fissile material. The combined mass of all of the uranium oxides in all the standard vials was determined by NDA to be 18 +/- 9 grams U-235 with an average enrichment of 18 wt% U-235. Due to the low mass and absence of moderation, the safety significance is low.

POTENTIAL CRITICALITY PATHWAYS INVOLVED [BRIEF SCENARIO(S) OF HOW CRITICALITY COULD OCCUR]:
Additional mass and a spacing violation would have been required before a criticality would be possible. Without moderation, much more than the safe mass of 350 grams of U-235 would have to be present before a criticality could be possible.

CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.):
This was an unanalyzed condition. Although not specifically controlled, the combined mass of all the uranium oxides in all the standard vials was less than a safe mass, moderation was not present, and the uranium oxide vials were spaced at least two feet from any other fissile material.

ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL (INCLUDING PROCESS LIMIT AND % WORST CASE OF CRITICAL MASS):
NDA shows the combined mass of all of the uranium oxides in all the standard vials to be 18 +/- 9 grams of U-235 with an enrichment of 18 wt% U-235. The material is in the form of dry oxides. For a spherical system at optimum moderation, full water reflection, and 100 wt% enrichment, the safe mass is 350 grams U-235.

NUCLEAR CRITICALITY SAFEEY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION OF THE FAILURES OR DEFICIENCIES:
The request failed to identify the presence of uranium oxide vials in the room resulting in an unanalyzed condition. The uranium oxides are less than a safe mass and other uranium bearing material was spaced at least two feet edge-to-edge from the uranium oxides.

CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEM AND WHEN EACH WAS IMPLEMENTED:
The uranium oxide vials were removed from the X-710 room 117 under applicable plant approved NCSAs. Total mass of material in X-710 room 117 is currently less than 15 grams U-235.

The NRC Resident Inspector and the site DOE Representative were notified.

PTS-2000-038; PR-PTS-00-01697.