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On October 9, 2016 at 0254 hours, with Unit 1 and Unit 2 at 100 percent power, Unit 2 experienced an automatic reactor trip initiated by a turbine trip due to generator differential lockout relay actuation. At the time of the trip, high wind and heavy rain conditions existed due to the effects of Hurricane Matthew. All three auxiliary feedwater pumps automatically started on low-low steam generator water level as expected. All plant systems functioned as required, and Unit 2 was stabilized at hot shutdown. The trip response was not affected by any previously inoperable systems, structures, or components.

The direct cause of the generator differential lockout was an electrical ground overcurrent initiated by water accumulation in the "A" phase of the "A" station service transformer leads termination enclosure. Affected electrical enclosures were drained, the system was tested, and modifications to the enclosures to prevent recurrence of water intrusion were completed prior to returning Unit 2 to power operation on October 13, 2016.

This report is being submitted pursuant to 10CFR50.73(a)(2)(iv)(A) as an event that resulted in the automatic actuation of the Reactor Protection System' and the Auxiliary Feedwater System.

On July 21, 2015 at 05:05, with Unit 1 at Hot Shutdown and Unit 2 at approximately 6% power, Unit 2 experienced a reactor trip initiated from a turbine trip during performance of the Turbine Overspeed Protection Control system circuitry testing. The turbine trip was caused by governor valves rapidly opening due to a speed error which had accumulated between the turbine speed and reference setpoint resulting in a rapid increase in impulse pressure. The root cause of this event was inadequate instructions in the Overspeed Protection Control testing section of the operating procedure. The testing will be removed from operating procedures and placed in test procedures that are not performed as part of routine turbine startup.

All systems functioned as required. Initiation of auxiliary or emergency systems was not required. Unit 2 was placed in hot shutdown and the health and safety of the public were not affected.

This report is being submitted pursuant to 10CFR50.73(a)(2)(iv)(A) as an event that resulted in the automatic actuation of the Reactor Protection System.

On April 30, 2014, with Unit 2 in cold shut down for a refueling outage, the Unit 2A pressurizer safety valve failed its as-found test due to the lift setting being lower than the setpoint tolerance allowed by Technical Specifications.

On May 6, 2014, the Unit 2C pressurizer safety valve also failed its as-found test due to the lift setting being lower than the setpoint tolerance allowed by Technical Specifications.

The as-found pressurizer safety valve lift settings were evaluated and it was determined the valves were capable of performing their safety function with the low as-found lift settings. Therefore, the health and safety of the public were not affected.

This report is being submitted, pursuant to 10 CFR 50.73(a)(2)(i)(B), for operation prohibited by Technical Specifications.

On August 14, 2015 at approximately 0830 hours, with Surry Power Station Units 1 and 2 operating at 100% power, a Virginia Electric and Power Company (Dominion) Nuclear Security Officer was told by a truck driver that he had portions of a disassembled weapon inside his backpack with the rest of the weapon located inside of his delivery truck. The driver informed the Security Officer of the contraband during a routine delivery truck search in the vehicle sally port, which is the vehicle search area for entry into the station's protected area. The truck driver was denied protected area access and he and the delivery truck were escorted off-site.

At 0850 hours on August 14, 2015, a one-hour notification was made to the NRC pursuant to 10CFR73, Appendix G, item 1(d), for an attempted introduction of contraband into a protected area.

This Licensee Event Report is being submitted pursuant to 10CFR73.71(a)(4) for a 60 day follow-up written report.

At 11:40 on March 29, 2014, with both Unit 1 and Unit 2 operating at 100% power, the Unit 1D service water header was declared inoperable as a result of indications received during testing. The direct cause of the indications was due to a mostly closed service water header isolation valve for the Unit 1D service water header. In October 2013, following valve replacement, the valve handwheel was re- oriented causing the valve to become mostly closed while indicating open. Therefore, the Unit 1D service water header was inoperable from October 21, 2013 until March 29, 2014 and Technical Specification limiting conditions of operation were exceeded twice during timeframes when one of two other operable service water headers was tagged out for maintenance. Also, as a result of the restricted flow condition, a service water pump that supplies cooling to a charging pump was also determined to be inoperable beyond its Technical Specification limiting conditions of operation.

• Therefore, this report is being submitted, pursuant to 10 CFR 50.73(a)(2)(i)(B), for operations prohibited by Technical Specifications. Based on the risk assessment of this event, the risk impact was determined to be very small and, as a result, the health and safety of the public were not affected.

On September 24, 2009, with Units 1 and 2 at 100% reactor power, it was discovered that the three emergency service water (ESW) pump oil cooler outlet lines, which penetrate the pump base plates, were not sealed to prevent pump house water intrusion. The ESW pump house is designed to withstand flooding from hurricane driven tidal surges of 22.7 feet. With the pump base plates at approximately 18 feet above sea level, potential pump inoperability would occur if the water level rises above 18 feet. The cause evaluation identified that in the 1990's, the threaded interface seals on the outlet lines were no longer utilized.DThe evaluation also found the apparent cause to be inadequate procedural guidance for sealing the outlet lines.DFollowing discovery, seals were installed.DThe maintenance procedure has been strengthened to prevent recurrence.DAn evaluation determined this issue to be of very low risk significance, therefore, the health and safety of the public was not affected. This report is being submitted pursuant to 10 CFR 50.73(a)(2)(i)(B), any event or condition which was prohibited by Technical Specifications.

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