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On March 17, 2016, at 0115 (EDT), Watts Bar Unit 1 (WBN1) entered Technical Specification Limiting Condition of Operation (TS LCO) 3.0.3 due to the inoperability of both trains of the Emergency Gas Treatment System (EGTS). TS LCO 3.7.12 Condition B was also entered at this time due to the inoperability of both trains of the Auxiliary Gas Treatment System (ABGTS). The train B EGTS and train B ABGTS had been removed from service for scheduled maintenance, when at 0115, the train A Auxiliary Air Compressor became inoperable. On March 17, 2016, at 0133, the train A Auxiliary Air Compressor was declared OPERABLE, and TS LCO 3.0.3 and 3.7.12 Condition B were exited. The auxiliary air system supports the EGTS by providing a safety grade air supply. When train A auxiliary air became inoperable, the supported train A EGTS and ABGTS became inoperable, creating a condition where both trains of EGTS and ABGTS were unavailable. In the event of an accident, the EGTS establishes a negative pressure in the annulus between the shield building and the steel containment vessel and the ABGTS establishes a negative pressure in the Auxiliary Building Secondary Containment Enclosure (ABSCE). Filters in these system mitigate the release of radioactive contaminants to the environment. WBN1 remained in Mode 1 at 100% power and no safety functions were required during the event. This event is reportable under 10 CFR 50.72(b)(3)(v)(C) and (D) as a condition that could have prevented the fulfillment of a safety function. The NRC Resident Inspector has been notified.

• * * RETRACTION AT 1518 EDT ON 04/19/16 FROM BRIAN MCILNAY TO JEFF HERRERA * * *

The purpose of this notification is to retract event report no. 51795 made on 3/17/16 at 0802 (EDT). Previously, Tennessee Valley Authority (TVA) reported a loss of the Emergency and Auxiliary Building Gas Treatment Systems (EGTS/ABGTS) at Watts Bar Nuclear Plant Unit 1 (WBN1). Both trains of EGTS and ABGTS were declared INOPERABLE when the train A auxiliary air system cooling water supply bypass valve was isolated, prior to completing the requisite post maintenance testing following repairs to the normal cooling water supply solenoid valve. Upon recognition, WBN1 operations personnel declared the train A auxiliary air system INOPERABLE, resulting in inoperability of Train A EGTS and ABGTS and forcing entry into TS LCO (Limiting Condition for Operation) 3.0.3 (from TS LCO 3.6.9 EGTS) and 3.7.12 Condition B for ABGTS. At the time the condition was recognized, train B EGTS and train B ABGTS were INOPERABLE for scheduled maintenance. Subsequently, TVA completed the post maintenance testing of the train A auxiliary air system ERCW (Emergency Raw Cooling Water) normal supply solenoid valve and determined that the valve, while not fully qualified at the time, was in fact operable and capable of performing its safety function. Therefore, entry into TS LCO 3.0.3 and 3.7.12 Condition B was not necessary and the event is no longer reportable under 10 CFR 50.72(b)(3)(v)(C) and (D) as a condition that could have prevented the fulfillment of a safety function. The NRC Resident Inspector has been notified. Notified the R2DO (McCoy).

In accordance with Instrument Maintenance Instruction (IMI) 99.040, 'Auto Safety Injection (SI) Block, Feedwater Isolation Block, and Maintain Source Range In Service Jumpers,' jumpers were placed to block the SI automatic actuation logic and actuation relays during WBNs (Watts Bar Nuclear) Cycle 8 refueling outage. The automatic actuation function for SI is required in Modes 1, 2, 3, and 4 per Function 1.b of Table 3.3.2-1 of Technical Specification (TS) 3.3.2, 'ESFAS Instrumentation.' WBN entered Mode 4 at 0020 EDT on March 20, 2008 and Mode 3 at 0100 EDT on March 21, 2008. On March 21, 2008, it was discovered that the jumpers installed per IMI-99.040 had not been removed. Due to this, Limiting Condition for Operation (LCO) 3.0.3, was entered at 0913 EDT and exited at 0958 EDT when the system was restored. The jumpers being in place in Mode 4 and 3 rendered both trains of SI automatic actuation inoperable for approximately 33 hours and 38 minutes. This event is being reported under 10 CFR 50.72(b)(3)(v)(D), 'Event or Condition that could have Prevented Fulfillment of a Safety Function.' The licensee attributes the error to a combination of both procedural inadequacy (i.e., the step removing the jumper did not require verification) and personnel error. The licensee informed the NRC Resident Inspector.

• * * UPDATE PROVIDED BY DOUGLAS HOLT TO JOE O'HARA AT 0213 ON 03/22/08 * * *

This is a follow-up notification to EN#44085 to amend reported information. At 2133 on 3/21/08 when permissive P-11(Low Pressure and Low Steamline Pressure) blocks were cleared, the on-shift crew questioned the presence of the 'AUTO SI Blocked' alarm and determined that it should have been cleared when the SI automatic logic jumper was removed earlier in the day. The crew utilized the procedural guidance of GO-1 to cycle the reactor trip breakers and reinstate the automatic safety injection logic at 2206 on 3/21/08. The previous report that identified that LC0 3.0,3 was exited at 0958 EDT is to be amended. LCO 3.0.3 was exited at 2206 when SI automatic logic was completely reinstated by cycling the reactor trip breakers. The licensee notified the NRC Resident Inspector. Notified R2DO(Ernstes)