Their greatest sin is they could anticipate this.
"Due to the fact that the failure exceeded expected conditions, this event is being reported per 10 CFR 50.72(b)(3)(ii)(A), as any event or condition that results in the condition of the nuclear plant, including its principle safety barriers, being seriously degraded."
See how it again is reported as a split 10 inch pin and not a cracked off cap.
Bet you these pellet glowed in the dark...Cherenkov radiation.
Again, the radiological effects of the lost pellets will create a large increase in the collective dose of the plant employee over years and decades. It will tremendously increase the burdens on the employees with radiation protection and it will create a large increase of cost and time in maintenance and ops. It will globally dilute the effectiveness of employees across the board
It will heavily fall on a small proportion of the employees, namely ops, maintenance, rad and chem.
Notification Date: 09/15/2014
Notification Time: 14:54 [ET]
Event Date: 09/15/2014
Event Time: 09:00 [EDT]
Last Update Date: 09/30/2014Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(ii)(A) - DEGRADED CONDITION
74.11(a) - LOST/STOLEN SNM
20.2201(a)(1)(ii) - LOST/STOLEN LNM>10XPerson (Organization):
SCOTT SHAEFFER (R2DO)
Event Text
Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode 2 N N 0 Refueling 0 Refueling
FAILED FUEL ASSEMBLY IDENTIFIED DURING CORE OFF-LOAD
"With North Anna Unit 2 in Mode 6 during a scheduled refueling outage, discharged assembly 4Z9 was identified as a failed fuel assembly by In-Mast Sipping. The fuel assembly was located in core location B11. Initial inspection of the fuel assembly identified two (2) visibly split fuel pins of eight (8) to ten (10) inches long with visible damage to the top of the pins. The internals of the affected pins are visible and the springs from the top of each pellet stack are touching the top nozzle. The fuel assembly has been placed into its designated location in the Spent Fuel Pool. No abnormal increase was noted on any radiation monitor either after or during fuel assembly movement. This fuel assembly had been used during three (3) previous operating cycles and is not scheduled for reuse.
"On September 15, 2014, at 0900 [EDT], subsequent video inspection of the fuel assembly identified that the top springs of the two (2) fuel pins were dislodged. Video inspection of the reactor vessel identified debris that has the potential to be fragments of fuel pellets resting on the core plate. Additional investigations are in progress.
"Due to the fact that the failure exceeded expected conditions, this event is being reported per 10 CFR 50.72(b)(3)(ii)(A), as any event or condition that results in the condition of the nuclear plant, including its principle safety barriers, being seriously degraded."
The licensee has notified the NRC Resident Inspector and will notify local county authorities.
* * * UPDATE FROM PAGE KEMP TO HOWIE CROUCH AT 1227 EDT ON 9/30/14 * * *
"Event Notification #50457 was provided on September 15, 2014, at 1454 hours, pursuant to 10 CFR 50.72(b)(3)(ii)(A), to provide notification that North Anna Unit 2 discharged assembly 4Z9 had two visibly split fuel pins and debris on the core plate that had the potential to be fuel pellet fragments.
"Detailed video inspections estimated that fifteen (15) fuel pellets were dislodged from fuel assembly 4Z9. For reference, the reactor core contains approximately 15 million fuel pellets. Efforts to identify and recover the fuel pellets were performed. Debris fragments, estimated to represent five (5) fuel pellets, were located within the damaged fuel assembly that is currently in the spent fuel pool. In addition, an estimated three (3) pellets worth of material was retrieved by the foreign object search and retrieval (FOSAR) efforts in the reactor vessel. The remaining seven (7) fuel pellets have already or are expected to granulate into fine particles that will remain in low flow areas of the primary plant systems or be removed by normal purification processes. However, since the specific location of the seven (7) fuel pellets is undesignated, a report is being made pursuant to 10 CFR 74.11(a) for the loss of special nuclear material.
"The seven (7) fuel pellets contain licensed material in a quantity greater than 10 times the quantity specified in Appendix C of 10 CFR 20; therefore a report is also being made pursuant to 10 CFR 20.2201(a)(ii).
"The cause of the fuel clad degradation is understood and is being addressed. It has been evaluated that the dispersion of fuel pellet material will pose no threat to the integrity or operation of the reactor fuel and primary system components. Reactor Coolant System activity will remain below Technical Specification limits during power operation. In addition, there are no adverse radiological consequences to the public as a result of this issue."
The licensee will be notifying the state of Virginia, local authorities in Louisa County and has notified the NRC Resident Inspector.
Notified R2DO (Vias) and IRD (Stapleton).
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