Event Notification Report for May 31, 2012

60-DAY OPTIONAL TELEPHONIC NOTIFICATION FOR AN INVALID PRIMARY CONTAINMENT ISOLATION VALVE ACTUATION

"At 0535 [PDT] on 5/31/12 during power ascension following a maintenance outage, a loss of power to the Reactor Protection System (RPS) 'B' occurred due to the unexpected opening of the circuit breaker (RPS-CB-MG2) for the RPS 'B' motor generator. The loss of RPS 'B' resulted in a half scram signal, closure of Primary Containment Isolation Valves (PCIVs) from multiple systems and loss of power to main steam line radiation monitors (MS-RIS-610B & MS-RIS-610D). No plant parameters or maintenance activities existed which would cause the opening of RPS-CB-MG2; therefore, this is considered to be an invalid actuation of a system listed in 10CFR50.73(a)(2)(iv).

"The half scram signal, closure of Primary Containment Isolation Valves (PCIVs) from multiple systems, and loss of power to MS-RIS-B & D were an expected response to the loss of RPS 'B'.

"Power ascension was temporarily halted. RPS 'B' was repowered from an alternate power supply. The half scram signal was reset, the containment isolation valves were opened and the affected systems were returned to normal operation. Power ascension was resumed. The circuit breaker (RPS-CB-MG2) was replaced and RPS 'B' was returned to its normal power supply.

"Initial investigation efforts have not determined a cause for RPS-CB-MG2 opening. Investigations into the cause of RPS-CB-MG2 opening are continuing.

"As indicated in 10CFR50.73(a)(1), in the case of an invalid actuation reported under 10CFR50.73(a)(2)(iv)(A), the licensee may, at its option, provide a telephonic notification to the NRC Operations Center within 60 days of discovery of the event instead of submitting a written LER. This 60-day telephone notification is being made to meet the reporting requirements instead of submitting an LER since the actuation was invalid.

"The following additional information is provided as specified in NUREG-1022:

"The specific train(s) and system(s) that were actuated: PCIVs in multiple systems
EDR-V-19 Drywell Equipment Drain Inboard Isolation Valve
EDR-V-20 Drywell Equipment Drain Outboard Isolation Valve
FDR-V-3 Drywell Floor Drain Inboard Isolation Valve
FDR-V-4 Drywell Floor Drain Outboard Isolation Valve
RWCU-V-1 Reactor Water Cleanup Suction Inboard Isolation Valve
RWCU-V-4 Reactor Water Cleanup Suction Outboard Isolation Valve
RRC-V-19 Reactor Water Sample Inboard Isolation Valve
RRC-V-20 Reactor Water Sample Outboard Isolation Valve
TIP-V-15 Traversing In-Core Probe Purge Isolation Valve
CRD-V-11 Control Rod Drive Scram Discharge Volume Drain Valve

"Whether each train actuation was complete or partial:
All PCIVs actuations for a loss of RPS 'B' were complete
The reactor half scram for a loss of RPS 'B' was a partial activation

"Whether or not the system started and functioned successfully:
All PCIVs functioned successfully"

The licensee notified the NRC Resident Inspector.

TRANSPORT OF POTENTIALLY CONTAMINATED PERSON OFFSITE

"At 11:11 PM on May 31, 2012, the Harris main control room was notified that a contract employee in a radiation controlled area was in need of medical assistance. The individual was transported by ambulance to the hospital, accompanied by Harris radiation protection personnel. The individual was considered potentially contaminated because a complete survey to confirm the absence of contamination was not completed prior to transport of the person off site for medical treatment. The individual and the ambulance used to transport the individual were surveyed and released after arrival at the hospital."

The licensee has notified the NRC Resident Inspector.

OFFSITE NOTIFICATION CONCERNING LOSS OF AMERTAP BALLS

"At 0304 CDT, Prairie Island Nuclear Generating Plant notified the Minnesota State Duty Officer that 1000 Amertap balls were lost from the Unit 1 condenser tube cleaning system. Since the Minnesota State Duty Officer was contacted, this constitutes an 4 hour non-emergency notification per 10 CFR 50.72(b)(2)(xi).

"The licensee has notified the NRC Resident Inspector."

The licensee will notify local and other government agencies.

PART 21 - DUCTILITY OF REINFORCING STEEL FOR EMBEDMENTS NOT IN ACCORDANCE WITH CODE REQUIREMENT

"The reporting organization provided information pertaining to the identification of a noncompliance associated with the steel reinforcing material (rebar) attached to embedments being supplied as basic components for the Vogtle Units 3 and 4, nuclear project, based on reinforcing bar that exceeded the limit for yield strength.

"The results of the evaluation of this condition as documented by Shaw Nuclear and conducted in accordance with the procedure for performing evaluations required by 10 CFR 21.21, has concluded that the noncompliance could potentially create a substantial safety hazard, if it were to remain uncorrected. Therefore, it has been determined that this noncompliance is reportable under the requirements of 10 CFR Part 21."

EN Revision Imported Date : 10/2/2020

EN Revision Text: AGREEMENT STATE REPORT - LOST TRITIUM EXIT SIGNS

This is information received from the state of Nebraska via email:

"In conducting a search for records for NRC Event #54500, it was determined that Home Depot #3210 was remodeled at the same time as Home Depot #3208 in Grand Island, NE and all (16) tritium exit signs were exchanged for LED in May 2012. Disposal records are unavailable due to Staybright Electric, the contractor in charge of replacement and disposal, going out of business. Home Depot was unable to produce disposal records but it is their belief that the signs were disposed of properly as Staybright conducted tritium exit sign removals for other Home Depots in the region prior to their closing for which records of disposal were obtained, demonstrating knowledge of proper procedure.

"The State of Nebraska also checked with Tritiumdisposal.com and SRBT in attempt to locate records as the outlets of disposal for Staybright, but no records were found.

"Home Depot currently has a plan in place that was submitted to the NRC in July of 2009 for facility management to reiterate tritium exit sign management requirements to existing vendors to ensure signs are managed within NRC requirements. As part of ongoing tritium exit sign servicing it is very reasonable to believe that Staybright transferred and disposed of tritium exit sign inventory properly. Home Depot continues to proactively address and replace (as appropriate) its remaining tritium exit sign inventories through the use of professional, third party vendors and continues to responsibly manage its existing inventories at current stores throughout the United States.

"A Home Depot corporate representative will track all purchases and returned signs to ensure accurate inventory and disposal.

"All Tritium Exit Signs have been replaced with LED.

"Home Depot will no longer install tritium exit signs within newly constructed locations."

Nebraska Item Number: NE200006

* * * RETRACTION ON 10/1/2020 AT 1020 EDT FROM DEB WILSON TO ANDREW WAUGH * * *

This is information received from the state of Nebraska via email:

"While the Home Depots were remodeled at similar times, it was found that the tritium exit signs at Store 3210 in Scottsbluff were kept in service until the end of their useful life. Records were recovered showing all signs being disposed of by Curie Environmental Services in Albuquerque, NM on 9/20/2019."

Notified R4DO (Silva), NMSS Events (email), and ILTAB (email).

THIS MATERIAL EVENT CONTAINS A "LESS THAN CAT 3" LEVEL OF RADIOACTIVE MATERIAL

Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. For additional information go to http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf