Event Notification Report for April 12, 2015

POTENTIALLY CONTAMINATED INDIVIDUAL TRANSPORTED OFFSITE DUE TO HEAT EXHAUSTION

"On 4/12/2015 at approximately 1230 CDT, an Xcel Energy employee performing activities in the drywell (currently shut down for a planned refueling outage), experienced heat exhaustion. Upon discovery, the plant emergency medical team was dispatched to aid the individual. The individual was immediately transported, via ambulance, to a local hospital for treatment without verification that no contamination existed. Accompanying the individual were two (2) radiation protection individuals. The individual was transported out of the Protected Area at approximately 1250 CDT. Because the potentially contaminated individual could not be surveyed prior to being transported offsite, the individual was considered potentially contaminated. As such, this event is being reported as an 8-hour prompt report pursuant to 10 CFR 50.72(b)(3)(xii).

"On 4/12/2015 at approximately 1340 CDT, the radiation protection personnel that accompanied the individual to the medical facility reported that the individual, ambulance, gurney, hospital travel path and exam room were determined not to be contaminated. As a result, no follow-up status report is planned.

"The licensee notified the NRC Resident Inspector."

The licensee will be notifying the State Duty Officer.

TEMPORARY LOSS OF CONTROL ROOM ENVELOPE BOUNDARY

"The purpose of this report is to provide a telephone notification under 10 CFR 50.72(b)(3)(v)(D) to notify the NRC of a temporary loss of the Control Room Envelope (CRE) boundary. The safety function of the CRE boundary is to ensure the in-leakage of unfiltered air into the CRE will not exceed the in-leakage assumed in the licensing basis analysis of design basis accident (DBA) consequences to CRE occupants. In addition to an intact CRE boundary maintaining CRE occupant dose from a large radioactive release below the calculated dose in the licensing basis consequence analysis for DBAs, it also ensures the occupants are protected from hazardous chemicals and smoke.

"The loss of the CRE boundary was due to a failed latching mechanism for a CRE boundary door used for normal passage of personnel into and out of the CRE. The failure of the door to latch as designed is considered a condition that could have prevented the fulfillment of a safety function at the time of discovery, and is therefore reportable as required by paragraph 50.72(b)(3), 'Eight-hour reports.'

"Procedural controls have restored the safety function of the CRE boundary by mechanically locking the subject door in the closed position through the use of a specifically designed mechanical strong-back until a permanent repair is made.

"The NRC Resident Inspector has been notified."

* * * RETRACTION FROM MARK HAWES TO JOHN SHOEMAKER AT 1642 EDT ON 6/1/15 * * *

"The main control room corridor fire door (76FDR-A-300-10) was found to not be able to latch. The latch was stuck in the latch mechanism because the latch bolt was bent. The latch was replaced on 4/15/2015.

"The Control Room Emergency Ventilation Air Supply System (CREVAS) provides a protected environment from which occupants can control the plant following an uncontrolled release of radioactivity, hazardous chemicals, or smoke. The Control Room Envelope (CRE) is the physical boundary around the CREVAS environment. The Operability of the CRE boundary depends on its ability to minimize in-leakage of unfiltered air such that after a design bases accident a habitable environment can be maintained for 31 days without exceeding 5 rem whole body dose or its equivalent to any part of the body.

"The control room is normally pressurized greater than the 0.125 inches water gauge. This causes air to leak out rather than allowing infiltration of air from surrounding areas into the CRE boundary. The pressurized control room pushes this door (76FDR-A-300-10) outward, toward the open direction; however, even though the latch to the door did not work the door was still able to close. The closed door minimized in-leakage and a positive differential pressure was maintained in the control room during this event. These doors are kept closed against the door seals primarily by the closure mechanism. The latch is a secondary means of ensuring that the doors remain closed as well as a means to control personnel access to the control room.

"The Control Room Envelope (CRE) remained Operable with this deficiency and there was no loss of safety function per 10 CFR 50.72(b)(3)(v)(D). The original notification may be retracted."

The licensee has notified the NRC Resident Inspector.

Notified the R1DO (Powell).

60-DAY OPTIONAL TELEPHONIC NOTIFICATION FOR AN INVALID CONTAINMENT ISOLATION ACTIVATION.

"This 60-day telephone notification is being submitted in accordance with 10 CFR 50.73(a)(1) and 10 CFR 50.73(a)(2)(iv)(A) to report an invalid actuation of the Train B Phase A Containment Isolation at Sequoyah Nuclear Plant.

"At 1320 EDT on April 12, 2015, during planned performance of the Containment Isolation Train-A, Phase A Isolation Testing and Emergency Gas Treatment System (EGTS) Cleanup System Test, the main control room received several Train-B annunciators. Upon investigation, it was determined that an invalid signal to the Train-B Solid State Protective System (SSPS) actuated the Train B, Phase A Containment Isolation. The invalid isolation signal was the result of a human performance error during the performance of the Phase A Isolation Test surveillance procedure. Operations personnel responded to the SSPS initiation, testing was aborted, ensured that all equipment operated as designed and restored affected systems in accordance with plant procedures. Approval to restart testing was obtained. All prerequisites were met and testing of the SSPS Train-A, Phase A Isolation was completed satisfactorily.

"As part of the prerequisite test alignment of the Train-A, Phase A, Unit 2 had entered a planned 7 day action for EGTS being inoperable. During the test when the Train-B of Phase A actuated, the suction dampers for Unit 1 supply to EGTS were closed per plant procedures. This prevented Train-B EGTS from aligning to Unit 1 and allowed Train-B of EGTS to remain operable for Unit 2. An SSPS Phase A signal can be generated automatically by a Safety Injection Signal (SIS) or manually. At the time of the event, plant conditions for an SIS did not exist; therefore, the Phase A actuation was invalid.

"The licensee notified the NRC Resident Inspector."