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While in Mode 5, refueling Shutdown with Core offload in progress a fuel assembly in the Spent Fuel Pool became ungrappled. The assembly is currently sitting on the top of the Spent Fuel pool racks resting against the Pool wall at approximately 15 degrees. There is no damage to the Fuel Assembly, evident by no change in area radiation dose rates. EAL 1.14, Plant Conditions Warrant Increased Awareness By Plant Staff or Government Authorities. An investigation has begun to determine the cause of the event and a team is being assembled to plan the fuel bundle recovery. The licensee notified the NRC Resident Inspector.

• * * UPDATE ON 9/23/03 AT 1857 EDT FROM RANDY CABE TO GERRY WAIG * * *

The licensee remains in a NOUE (Notice of Unusual Event) due to the ungrappled spent fuel assembly. The position of the spent fuel assembly remains the same as previously reported. No damage to the fuel assembly nor the spent fuel rack has been detected. No abnormal radiation readings have been observed. As a precaution, the licensee has suspended all fuel movement operations and evacuated the auxiliary and containment buildings. The licensee plans to stabilize the fuel assembly, attach a lifting tool, and place it into a permanent storage position in the spent fuel pool. Notified R4DO (Greg Pick)

• * * UPDATE ON 09/24/03 @ 1414 BY CADE TO GOULD * * *

At 12:42 CDT the fabricated stabilization device installation was completed and it is currently secured to two walls of the spent fuel pool. The plant will remain in a NOUE until the fuel assembly is lowered into a safe location in the spent fuel pool. A tool has been fabricated to grapple the fuel assembly and it will be moved with the Spent Fuel Pool Refueling Machine. The tool is currently being tested and weighed. All unnecessary personnel were moved from the Protected Area to the Administration and Training Buildings during the placement of the stabilization device. The NRC Resident Inspector was notified. Reg 4 RDO (Greg Pick) was notified

• * * UPDATE ON 09/24/03 @ 1800 EDT BY RANDY CADE TO GERRY WAIG * * *

The licensee reported that the ungrappled spent fuel assembly was placed in a permanent storage position in the spent fuel pool at 1654 CDT. As a result of this action, the licensee terminated the Notice of Unusual Event (NOUE) condition at this time. Normal access to the facility protected area and radiation control area has been restored. Fuel movement operations remain suspended and a root cause investigation of this event is being conducted. The licensee notified the NRC Resident Inspector. NRC R4DO (Greg Pick), DIRO (Richard Wessman), NRR EO (Gene Imbro), FEMA (Ken Sweetser), DOE (Joe Stanbaugh), DHS (Sam Neglia) were notified by the Headquarters Operations Officer.

Discovered vulnerability in a safeguard system that could allow access to a controlled access area for which compensatory measures have not been employed. The licensee will notify the NRC Resident Inspector. Contact the Headquarters Operations Officer for additional details.

• * * UPDATE from R. Lowery to R. Jolliffe at 1100 EST on 12/11/03 * * *

The licensee provided additional information about this event. Contact the Headquarters Operations Officer for additional details. Notified R4DO (D. Graves) and TAS (J. Whitney)

The following information was obtained from the licensee via facsimile: At 0920 (hrs.) CST, on February 8, 2005, Fort Calhoun Station declared the steam driven auxiliary feedwater (AFW) pump (FW-10) inoperable due to discovery of a design problem with the pump turbine. The station entered the appropriate technical specification action statement at that time. The pertinent action statements for auxiliary feedwater ((T.S.) 2.5.1) read as follows: B (Action statement): With one AFW train inoperable for reasons other than condition A, restore the AFW train to OPERABLE status within 24 hours. C (Action statement: If the required action and associated completion times of condition A or B are not met, then the unit shall be placed in MODE 2 in 6 hours, in MODE 3 in the next 6 hours, and less than 300 (degrees) F without reliance on the steam generators for decay heat removal within the next 18 hours. A change to the design basis is in progress to allow the pump to be made operable within 24 hours. The design problem is due to the AFW pump drains. The manufacturer states that the drain lines must drain below the level of the AFW turbine. The current configuration is that the drains are aligned to the condenser which is approximately 18 feet above the elevation of the AFW turbine. This is not a problem during normal AFW turbine operation as the condenser would most likely be in service. However, the condenser cannot be relied upon during all accident conditions that require AFW actuation. The licensee has notified the NRC Resident Inspector.

• • • RETRACTION - E. MATZKE TO J. KNOKE AT 11:44 EST ON 03/27/05 ***

The licensee faxed the following retraction: Fort Calhoun Station (FCS) has conducted a thorough engineering evaluation of the effects on water in the turbine exhaust housing of the steam driven feedwater pump (FW-10). It was concluded that FW-10 was able to perform its design function based on the results of the evaluation. FW-10 was determined to be operable as required during past plant operation whether or not condenser vacuum was available. The conclusion was based on four points: 1. The preparer's experience with a multi-stage turbine that was started with water up to the centerline of the rotor and sustained no damage. 2. OPPD's strong evidence that FW-10 has been operated multiple times with some water in the casing. 3. A simple conservative analysis of the forces on a turbine blade when operated in a water submerged condition. The blade stresses were determined to be well below allowables for the loading condition presented with the blade moving through the static water volume during a startup event. 4. In addition, inspection of the turbine in 1998 and 2005 does not show any adverse indications of stress or wear. Therefore this notification is being retracted.. The plant is presently in a scheduled refueling outage. The licensee will notify NRC Resident Inspector.

On 8/12/05 at 1550, Fort Calhoun Station was notified by an off-duty employee that an emergency siren was sounding in Washington County, Nebraska. No actual emergency exists and no testing is currently in progress. The siren's location is approximately 1/2 mile East of the P32/P35 county road intersections on county road P32. The local sheriff, radio station (KFAB), and NRC senior resident have been notified. The cause of the inadvertent siren activation is unknown at this time. This event is considered to be reportable per 10CFR50.72(b)(2)(xi). This siren is within 10 miles from the plant. The local sheriff will provide compensatory notifications if required. The licensee notified the NRC Resident Inspector.

• * * RETRACTING EVENT BY LICENSEE (MARASCO) TO ABRAMOVITZ AT 2135 ON 8/12/2005 * * *

The licensee determined that their corporate communications department had been performing a test of the emergency sirens but had not notified the site. Notified the R4DO (Bywater) and e-mailed R4 (Graves and Dricks). The licensee notified the NRC Resident Inspector.

During a review of two nonconformances documented in the station's corrective action system, an unanalyzed condition which could significantly degrade plant safety was noted. The steam generator level instrumentation was not installed as documented in the UFSAR. Letdown valves and piping inside containment was not installed as described in the UFSAR. An unacceptable scenario is a postulated design basis accident in one of the steam generators and a single failure of the letdown piping in the vicinity of the instrumentation piping of the other steam generator, which could, produce conditions that would mislead the operator as to the condition of the plant during the accident. This condition was discovered during steam generator replacement when the old steam generators were removed and the instrumentation piping became visible. The replacement piping will be routed in accordance with approved drawings. This piping is not required in the current mode. The licensee notified the NRC Resident Inspector.

• * * RETRACTION ON 11/07/06 AT 1152 EST FROM ERICK MATZKE TO MACKINNON * * *

Additional review of the situation previously reported has determined that there are no unanalyzed interactions between the SG level instrumentation tubing and the letdown system. The review determined that the previous determination was incorrectly postulating the occurrence of simultaneous accidents. This observation was not readily apparent during the initial review. Therefore this event is not reportable under 10CFR50.72. Event number 42902 is being withdrawn. However, the continuing review has identified a failure which will require reporting under part 50.73, but not 50.72. R4DO (Jeffrey Clark) notified. The NRC Resident Inspector was notified of the retraction of this event by the licensee.

On February 8, 2007 at 10:22 CST, Raw Water Pump AC-10C was declared inoperable when the pump breaker experienced a plunger linkage failure during a scheduled pump start for a scheduled rotation. Due to a similar failure of Raw Water Pump AC-10B two weeks earlier, a condition report was initiated for engineering to review the potential for a common failure mode. Engineering reviewed the number of cycles of the breakers for AC-10A and AC-10D both have greater than 1600 cycles. The breaker for AC-10B had over 1200 cycles at the time of its failure and AC-10C was over 1700 cycles. Based on the similar numbers of cycles, engineering has determined that continued operation of AC-10A and AC-10D without breaker failure could not he assured. All other safeguards associated breakers have been verified to have less than 1000 cycles and are not considered to be susceptible to breaker failure at this time. After discussion with engineering, Raw Water Pumps AC-10A and AC-10D were declared inoperable on February 8, 2007 at 13:42 CST based on the number of breaker cycles for these two components in relation to the two breakers that failed. With three Raw Water Pumps inoperable, Fort Calhoun Station entered Technical Specification 2.0.1 which requires the plant be placed in hot shutdown within six (6) hours. The potential for a common mode failure of the linkage in the 4160 VAC circuit breakers (ABB Combustion Engineering Model No. 5VKBR-250) could have prevented operation of the Raw Water Pumps to fulfill the required design function to remove residual heat during a design basis accident. At 15:22 CST, repairs were completed on Raw Water Pump AC-10C breaker and the pump was declared operable. At 15:34 CST, Technical Specification 2.0.1 was exited and Technical Specification 2.4(1)c, 7-day LCO was entered for the inoperability of Raw Water Pumps AC-10A and AC-10D. The repair of the breakers for AC-10A and AC-10D are scheduled for February 9, 2007. The licensee informed the NRC Resident Inspector.

• * * UPDATE AT 1632 EST ON 2/12/07 FROM ERICK MATZKE TO S. SANDIN * * *

This communication is meant to supplement the notification of February 8, 2007. The common mode failure of the linkage in the 4160V circuit breaker (ABB Combustion Engineering model number 5VKBR-250) could have prevented the operation of the raw water pumps as required by design. This could have resulted in the inability of the raw water system to remove residual heat during design basis accidents as required. The licensee informed the NRC Resident Inspector. Notified R4DO (Smith).

• * * RETRACTION FROM MATZKE TO HUFFMAN AT 1447 EDT ON 3/15/07 * * *

On February 3, 2007, (Event Number 43157) Fort Calhoun Station reported a condition that, at the time, was believed (to be) a possible common mode failure of the 4160V feeder breakers for the Raw Water (RW) System (redacted). The circuit breakers for two of the four RW pump feeder breakers had failed. Investigation had determined that the failure mechanism was the same for the two failures. On February 8, it was not known if the other two RW pump breakers could fail by this same mechanism. The component that failed in the circuit breaker was an offset rod that transmitted operation of the circuit breaker to a set of auxiliary switches associated with the circuit breakers. The offset rods of the A and D RW pumps have subsequently been tested. Non destructive testing determined that the rods had no cracks. Destructive testing determined that the rods would not have failed for several hundred operations of the circuit breakers. As a result, the system was capable of performing its design safety function. Therefore, this event is not reportable under 10 CFR 50.72(b)(3)(B) as previously reported and EN 43157 is being retracted. While no verbal report criteria is applicable to this condition it is reportable as an LER under 10 CFR 50.73(a)(2)(vii). The licensee notified the NRC Resident Inspector. R4DO ( Shannon) notified.

A Notification of an Unusual Event was declared at 06:01 EDT due to a chemical leak in the Turbine Building truck dock area near a roll-up door. The leak was discovered at 05:40 EDT coming from a line connecting two vertically stacked Hydrazine Metal chemical storage totes located inside a ventilated enclosure. The Hazmat Response Incident Team was formed to address the spill. Approximately 10 gallons is inside the enclosure berm. A small amount of liquid has leaked outside the enclosure berm but has been contained. Containment activities are in progress. Leak rate appears to be significantly less. Additional plant staff has been called in to support and are arriving on site at the time of this notification. The area has been roped off and plant announcements to warn personnel of this hazard have been made. (EAL-11.4, Plant Conditions Warrant Increased Awareness by Plant Staff) The licensee notified the NRC Resident Inspector, state and local government agencies.

* * *  UPDATE AT 0742 ON 9/13/07 FROM CHLADIL TO ROTTON * * *

The licensee terminated the Notice of Unusual Event. The termination criteria was that the spill was stopped and the licensee has established limited personnel access restrictions to the turbine building truck bay and the service building elevator. The licensee is continuing to clean the area. The licensee notified the NRC Resident Inspector and will be notifying state and local government agencies. Notified R4DO (Shannon), NRR (Ross-Lee), IRD (Blount), DHS (Haselton) and FEMA (Laforty).

At 11:42 CST, a condition report was initiated that questioned the specified flow path for simultaneous hot and cold leg injection following a large break loss of coolant accident (LOCA). When an unisolated LOCA event exists, simultaneous hot leg and cold leg injection should be implemented if the plant cannot be placed on shutdown cooling within six hours of the LOCA initiation and RCS pressure is less than 120 psia. The procedure is implemented at five and one-half hours to provide adequate time to align simultaneous hot/cold leg injection before the six hour time limit. Injecting to each side of the reactor vessel at an injection rate greater than 165 gpm, ensures that fluid from the reactor vessel (where the boric acid is being concentrated) flows out of the break regardless of the break location and is replenished with a dilute solution of borated water from the other side of the reactor vessel. The action is taken between 5.5 and 6 hours after the LOCA in order to ensure that the buildup of boric acid is terminated well before the potential for boric acid precipitation occurs which could restrict coolant flow through the core. Once the RCS is refilled, the boric acid is dispersed throughout the RCS via natural circulation. If entry into shutdown cooling system operation is anticipated before the 5.5 hour limit, then the realignment to hot/cold leg injection is unnecessary. The potential concern is associated with a charging line thermal relief valve CH-202 bypassing flow from hot leg injection and preventing the required flow rate needed to prevent boron precipitation from occurring. A minimum injection rate of 147 gpm to the cold legs and 159 gpm to the hot legs is required to prevent boric acid precipitation. Total hot leg injection flow is measured at FIA-236. Cold leg injection flow is the total of the four HPSI flow instruments, FI-313, FI-316, FI-319, and FI-322 with 50 gpm the minimum flow indication. A total cold leg injection flow of at least 200 gpm ensures at least 150 pm flow into the core, assuming 25% spillage out the break. This meets the required minimum of 147 gpm. It could not be determined through a review of the design basis documents and associated calculations what, if any, bypass flow is assumed through CH-202. Current procedural guidance in the emergency operating procedures is to align a high pressure safety injection pump to the charging header and provide hot leg injection from auxiliary pressurizer spray valves attached to the charging headers through the pressurizer and into the hot leg. The current procedural guidance does not isolate CH-202 and due to the location of flow instrument FIA-236, it cannot be guaranteed that all the flow through the charging system is being injected into the hot leg or being diverted through the normal charging line. As a result the potential existed which could have prevented the fulfillment of the safety function of a system needed to remove residual heat. Therefore this report is being made in reference to 10 CFR 50.72 (b) (3) (v) (B). Efforts are continuing to review design basis documents and calculations to determine if bypass flow was assumed past CH-202 when determining the minimum hot leg injection rate. As a compensatory measure, Operations management has restricted the use of hot and cold leg injection via the charging header until the design basis review confirms the adequacy of the current procedural guidance or the procedural guidance is revised. Pre-approved alternative methods will be utilized via the emergency operating procedures to perform simultaneous hot and cold leg injection if required. No LCO condition exists. The licensee notified the NRC Resident Inspector.

• * UPDATE FROM ERICK MATZKE TO JOHN KNOKE AT 1619 EST ON 02/20/08 * *

On January 8, 2008, (Event Number 43886) Fort Calhoun Station reported that there could be a potential reduction of injection flow to the hot leg during Long Term Core Cooling (LTCC) simultaneous hot and cold leg injection. The charging line thermal relief valve/check valve CH-202 could potentially divert flow from hot leg injection and reduce hot leg flow below the required flow rate needed to prevent boron precipitation from occurring. On January 8, 2008 it could not be determined through a review of design basis documents and associated calculations if bypass flow has been assumed through CH-202. Divergence of flow through CH-202 would result if a valve failure occurred. Assuming flow is diverted through CH-202, the operators would not realize that flow was going through the wrong flow path (cold leg) as their flow indication (FE-326) is located upstream of where the flow path to the hot leg and cold legs branch off. Therefore, there was nothing to alert the operator to isolate CH-202 or go to alternate hot leg injection. Previous procedural guidance was not adequate to address this condition. Current procedural guidance is adequate to address this condition as the procedures now require isolating CH-202 for LTCC. A reanalysis was performed to evaluate the required flow rate needed to prevent boron precipitation and ensure adequate LTCC. Calculations performed assumed full flow (failure) through CH-202. Under postulated design scenarios it was determined that adequate flow would have been provided to the hot legs during simultaneous hot and cold leg injection during LTCC. The calculations determined that under the evaluated scenarios, divergence of flow through CH-202 was acceptable, and that the requirements to maintain adequate flow to the core for LTCC decay heat removal and boron flushing would have been met. As a result of the analysis that were performed, it has been determined that the system was capable of performing its design function even under bypass flow conditions through CH-202. Therefore, this event is NOT reportable under 10 CFR 50.72( b) (3) (v) (B) as previously reported. The licensee notified the NRC Resident Inspector. Notified R4 DO (Miller)

Fort Calhoun Station will be experiencing a partial loss of emergency communications and notification capabilities on Wednesday, May 14, 2008. Omaha Public Power District will be completing an upgrade to the main radio system from approximately 05:00 - 09:00, Wednesday, May 14, 2008. During this time, mobility over the radio system (mostly rural use) and the Fort Calhoun Station Alert and Notification System (ANS) sirens will be out of service. Emergency Planning will notify the affected counties to have their back-up plan for the (alert and notification system) in place during that time. Post Maintenance Silent Testing will be performed upon completion of radio maintenance to verify siren communications. The licensee notified the NRC Resident Inspector.

• * * UPDATE AT 1157 EDT ON 5/14/08 FROM MATZKE TO HUFFMAN * * *

The licensee reports that the siren outage commenced at approximately 0400 CDT this morning and is in progress. Currently, the estimated completion time for this activity is now approximately 1300 CDT today (5/14/08). R4DO (Powers) notified.

• * * UPDATE PROVIDED AT 1847 EDT ON 05/14/08 FROM GUINN TO JEFF ROTTON * * *

Update to Event Number 44207 - Fort Calhoun Unit 1 - Event Date 05/14/2008 - Emergency Sirens upgrade is complete. Post maintenance silence testing was performed. All sirens are functional. The NRC Resident Inspector, state, and local officials have been notified. Notified R4DO (Powers)

On June 27, 2008 at 1430 CDT, Fort Calhoun Station (FCS) performed testing of the group paging system via the Interactive Notification System (INS) . The group page did not perform as designed. Further investigation and testing of the group page manually resulted in the same issue. It has been determined that the group page function is not operational. FCS has implemented backup manual callout process for the emergency response organization. Therefore emergency facility activation may take longer than normal. Troubleshooting efforts are ongoing. Licensee has notified NRC Resident Inspector.

• * * UPDATE FROM GUINN TO CROUCH @ 1023 EDT ON 6/30/08 * * *

Troubleshooting revealed a hard drive failure for the paging system. On June 27, 2008, the paging system was tested satisfactorily at 2145. System is fully functional. The licensee has notified the NRC Resident Inspector. Notified R4DO (Bywater).