ENS 50787
ENS Event | |
|---|---|
01:01 Feb 4, 2015 | |
| Title | Safety Equipment Disabled Due to Snow |
| Event Description | On 2/3/2015 at 1901 [CST], equipment important to safety failed to function as designed: 33 NAC MAGNASTOR systems containing Spent Nuclear Fuel, and 1 NAC MAGNASTOR system containing GTCC [Greater than Class C] waste, had air inlet vent partial blockage, totaling 50 percent or greater, due to environmental conditions, i.e., snow. (Please Note, no VCC systems reached full blockage.)
NO personnel radiation exposure. Actions Taken lAW the NAC FSAR, Rev. 5, which included actions to immediately return the systems to less than 50 percent blockage and ongoing maintenance activities to return all systems to full operability. Additional information: 1. On 2/4/2015 at 0445 hrs. All 34 failed systems were restored to less than 50 percent blockage. 2. lAW the NAC FSAR we have 30 days from time of discovery to return each system to full operability. 3. A report will be followed up within 60 days per 10 CFR 72.75.g The licensee will notify the NRC Inspector and the State of Illinois.
This phone notification is being made to retract an earlier '24 Hour Report' made on February 4, 2015 at 1815 CST, NRC event #50787. On February 4, 2015 at 1810 CST, Zion Station notified NRC that on February 3, 2015 at 1901 CST, Equipment Important To Safety failed to function as designed that being 33 NAC MAGNASTOR systems containing Spent Nuclear Fuel and 1 NAC MAGNASTOR containing GTCC waste had their Inlet vents partially blocked, totaling 50% or greater, due to environmental conditions, i.e. Snow. This appeared to meet criteria of Non-Emergency notification under 10 CFR 72.75d(1)(i). NAC International has provided documentation stating we have 58 hours6.712963e-4 days <br />0.0161 hours <br />9.589947e-5 weeks <br />2.2069e-5 months <br /> to perform the immediate action to unblock the VCC vents to greater than 50% and 30 days to completely unblock all the vents. This documentation is attached to this notification. Upon further review by Exelon Management, Zion Solutions Management and NAC, using criteria established in Sections 4.3.7.1 and 12.2.2 of the SER for CoC 72-1031, Amendment 0, no limits were exceeded. Actions were immediately initiated to restore the 34 failed systems to less than 50% blockage and were completed in less than 10 Hours. This is well within the 58 hour6.712963e-4 days <br />0.0161 hours <br />9.589947e-5 weeks <br />2.2069e-5 months <br /> SAR basis. This is the basis for retracting the notification. Based on the above, [the licensee] management concludes this event does not meet the 24-hour reporting criteria established in 10 CFR 72.75d(1)(i). The R3DO(Pelke) was notified. |
| Where | |
|---|---|
| Zion File:ZionSolutions icon.png Illinois (NRC Region 3) | |
| Reporting | |
| 10 CFR 72.75(d)(1), ISFSI Safety System Functional Failure | |
| Time - Person (Reporting Time:+18.23 h0.76 days <br />0.109 weeks <br />0.025 months <br />) | |
| Opened: | Dan Giernoth 19:15 Feb 4, 2015 |
| NRC Officer: | Daniel Mills |
| Last Updated: | Feb 9, 2015 |
| 50787 - NRC Website
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Unit 1 | |
|---|---|
| Reactor critical | Not Critical |
| Scram | No |
| Before | Decommissioned (0 %) |
| After | Decommissioned (0 %) |
Unit 2 | |
|---|---|
| Reactor critical | Not Critical |
| Scram | No |
| Before | Decommissioned (0 %) |
| After | Decommissioned (0 %) |
WEEKMONTHYEARENS 507872015-02-04T01:01:0004 February 2015 01:01:00
[Table view]10 CFR 72.75(d)(1), ISFSI Safety System Functional Failure Safety Equipment Disabled Due to Snow 2015-02-04T01:01:00 | |