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Criticality spacing configuration requirements for Integrated Fuel Burnable Absorber (IFBA) rod caskets were violated in the IFBA loading dock (Dock 9). IFBA rod caskets are used for transport of IFBA rods from the IFBA loading dock to the Quality Control (QC) Inspection Area. Criticality spacing requirements for the caskets are posted on the lid of each container. The requirements state that loaded caskets are required to remain in the same horizontal array with 12-inch spacing between all other containers not in the same array. As such, stacking of loaded caskets is prohibited. Contrary to this requirement, Westinghouse operations personnel identified several caskets loaded with IFBA rods that were stacked in the IFBA loading dock (Dock 9). It is believed that this spacing condition was present for less than 24 hours, although this has not yet been confirmed. Notification is being made based on the loss of spacing of the caskets in conjunction with the failure to limit the potential pathway for moderator introduction into the caskets (see discussion below for more detail). Double Contingency Protection The criticality safety analysis considers criticality not credible for normal and credible process upset conditions. However, the criticality safety analysis (ISA-12) also establishes that criticality is possible if large quantities of rods were stacked and interstitial moderation was provided and retained among the stacked fuel rods. Introduction of interstitial moderation is limited by the casket covers and through limitation of available sources. While no liquid moderator was present in any of the caskets, the potential pathway for moderator introduction was not addressed by either the criticality safety posting (deficiency in the criticality safety analysis) or operating procedures. In addition (as discussed under the Reason for Notification), the caskets were improperly spaced in a stacked configuration. It was determined that the criticality safety analysis is deficient and that less than two unlikely, independent, and concurrent changes in process conditions would be required before a criticality accident would be possible. A criticality is judged to be credible through the introduction of moderation and the incorrect configuration of the caskets. In accordance with Westinghouse Operating License (SNM-1107), paragraph 3.7.3 (b.3), this event satisfies the criteria for a 4-hour notification. Summary of Activity:

 IFBA casket loading operations were discontinued.
 Operations Management reviewed the procedural requirements prohibiting stacking of caskets with all of the operations personnel.
 The program to train and re-certify all Operations personnel is continuing, per schedule.  
 The program to assess and reconstitute the plant's criticality safety basis is continuing, per schedule.   
"Conclusions:
 Problem was self identified by Westinghouse Operations personnel.  As stated previously it is believed that the improper spacing configuration was present for less than 24 hours. 
 Less than double contingency protection remained.
 No liquid moderator was present in any of the caskets.
 At no time was the health or safety to any employee or member of the public in jeopardy.  No exposure to hazardous material was involved.
 The Incident Review Committee (IRC) determined that this is a safety significant incident in accordance with governing procedures.
 A causal analysis will be performed.
 The plant programs for training and recertification of operations personnel and for assessment and reconstitution of the plant's criticality safety    basis are appropriate corrective actions for this type of event and are continuing according to plan.

There is no NRC Resident Inspector at the site. The loading operations are estimated to be discontinued for 3 to 7 days.

An incorrect valve line-up caused a batch from the solvent extraction system to be pumped to the uranyl nitrate bulk storage tank without having the necessary sample results for grams U-235 per liter, percent free acid, and pH. It was determined that approximately 38 gallons of uranyl nitrate at 4.6 grams U-235, 8 percent free acid, and a pH of 1 was pumped to the bulk storage tank. These parameters meet the requirements for an authorized pumpout. The bulk storage tank contained approximately 1600 gallons of uranyl nitrate at approximately 1.4 grams U-235 per liter, 11.6 percent free acid, and a pH of 1. Double contingency protection for the bulk storage tank is based on concentration control. Concentration control is based upon maintaining uranyl nitrate that is pumped to the tanks at less than 5 grams U-235/liter. The pH is maintained at a value of less than 2 to ensure that the uranyl nitrate stays in solution. The percent free acid is maintained at greater than 4 percent to ensure that the uranyl nitrate stays in solution and depresses the freezing temperature of the solution to prevent concentration by freezing. It has been determined that less than previously documented double contingency protection remained for the system and that greater than a safe mass was involved, but a sufficient number of controls that were lost were restored within 4 hours. In accordance with Westinghouse Operating License (SNM-1107), paragraph 3.7.3 (c.5b), this event satisfies the criteria for a 24-hour notification. Summary of Activity All pumpouts to bulk storage tanks were stopped immediately upon recognition. This action was initiated by operators monitoring system performance. Samples for grams U-235/liter, pH, and %free acid were taken to ensure the tanks were in specification. Before the end of the shift, sample results for grams U-235/liter, pH, and %free acid were confirmed to be acceptable. At the beginning of each shift, operators are being informed of the incident. The procedure is being modified immediately to incorporate an additional peer check. Independent locks will be installed to require separate individuals to unlock the valve prior to pumpout.

Conclusions Loss of double contingency protection occurred. At no time was the health or safety to any employee or member of the public in jeopardy. No exposure to hazardous material was involved. The Incident Review Committee (IRC) determined that this is a safety significant incident in accordance with governing procedures. Notification was the result of an event, not a deficient NCS analysis. A causal analysis will be performed.

The following was submitted via email: Reason for Notification A canvas lined cart was found in the UF6 (Uranium Hexafluoride) bay. The cart dimensions met the criteria for a non favorable geometry (NFG) container however slits had been cut into the bottom of the cart. The presence of the slits makes it questionable as to whether or not this is a true NFG. Taking a conservative approach and assuming that the cart is an NFG, its presence in the Chemical area is prohibited by SNM-1107, Section 6.1.4 without a nuclear criticality safety analysis. In accordance with Westinghouse Operating License (SNM-1107), paragraph 3.7.3 (b.2), this event satisfies the criteria for a 4-hour notification. Specifically, any determination that a criticality safety analysis or evaluation was deficient, or that a particular system was not previously analyzed; and that less than two unlikely, independent, and concurrent changes in process conditions would be required before a criticality accident would be possible. As Found Condition An NCS (Nuclear Criticality Safety) Engineer was notified by a member of the EH&S (Environmental Health and Safety) Department that a canvas cart was in the UF6 bay. The canvas cart had several slits approximately five inches in length cut in the bottom that would preclude the build-up of liquid materials. There was no process equipment in the general area where the cart was located. There was no SNM (Special Nuclear Material) in the cart and the cart was not a part of any existing process. Summary of Activity

 -The cart was dismantled immediately.
 -NCS notified NRC Region II of the cart.

Conclusions

 -This particular system was not previously analyzed for criticality safety.
 -There was no SNM involved.
 -At no time was the health or safety to any employee or member of the public in jeopardy.  No exposure to hazardous material was involved.
 -The Incident Review Committee (IRC) has determined that this is a safety significant incident in accordance with governing procedures.
 -A causal analysis will be performed.

The Licensee notified Region 2 (Ayres, Crespo).

A review of incinerator data indicated higher than expected accumulations and concentrations of uranium bearing material in the incinerator off-gas system. Criticality was not possible because the mass corresponding to each concentration was below the minimum critical mass. Controlled Parameters: The safety basis for the incinerator off gas-system states that criticality is not credible. This was based on minimal expected carryover and low concentrations of uranium from the incinerator to the off -gas system. The uranium concentrations in the off-gas system were expected to be well below the (deleted) concentration criticality limit for an infinite mass. A criticality would be possible in the off-gas system only if a minimum critical mass for a corresponding uranium concentration accumulated in a critical configuration with sufficient moderator. Because higher than expected accumulation and concentration of uranium bearing material was detected in the incinerator off gas system, this 24-hour notification is being made. Summary of Activity: 1) Incinerator was shut down; 2) The off-gas system is being inspected; 3) Samples from the off-gas system are being obtained for analysis. Conclusions: 1). The bounding assumptions for concentration and carryover were exceeded; 2). At no time was there any risk to the health or safety of any employee or member of the public. No exposure to hazardous material was involved & 3). The Incident Review Committee (IRC) determined that this is a safety significant incident in accordance with governing procedures. A formal causal analysis will be performed. The licensee will be notifying NRC Region III.

• * * UPDATE AT 1346 EST ON 3/9/04 SNYDER TO GOTT * * *

The licensee sent the following addendum via facsimile: Reason for Addendum: Higher than expected concentration of uranium bearing material detected in the incinerator ash. The ash from the lower chamber of the incinerator is lifted via a bucket elevator and dumped into a mill feed hopper and then into a fitzmill. As Found Condition: A review of incinerator data indicated higher than expected concentrations of uranium in the incinerator ash. Controlled Parameters: The safety basis for the ash handling system (elevator and fitzmill) states that criticality is not credible based on the ash remaining below 21.6 weight percent uranium. Summary of Activity: -In addition to the previous activities, the formal root cause team has initiated their investigation. -The incinerator ash elevator and fitzmill safety basis is being re-evaluated. Conclusions: -The bounding assumption for concentration was exceeded. -At no time was there any risk to the health or safety of any employee or member of the public. -No exposure to hazardous material was involved. -The ash handling aspect will be incorporated into the formal causal analysis. Notified NMSS (Psyk) and R2D) (Ayres).