Event Notification Report for February 23, 2017

TECHNICAL SPECIFICATION SHUTDOWN DUE TO RCS PRESSURE BOUNDARY LEAKAGE

"On February 23, 2017, a containment visual inspection was performed to identify the source of elevated RCS [Reactor Coolant System] leakage. A leak was identified at the nozzle connection of the boron injection line to 2D RCS cold leg at 1922 [EST]. It was determined that the leak cannot be isolated and is considered RCS pressure boundary leakage. Unit 2 entered TS LCO 3.4.13, RCS Operational Leakage, Condition B, for the existence of pressure boundary leakage.

"This event is reportable in accordance with 10CFR50.72(b)(2)(i) (4 hours) for 'initiation of plant shutdown required by Technical Specifications' and 10CFR50.72(b)(3)(ii)(A) (8 hours) for 'any event or condition that results in the condition of the nuclear power plant, including its principal safety barriers, being seriously degraded.'

"The unit will shutdown and repairs will be performed in Mode 5.

"This condition has no impact on public health and safety.

"The licensee has informed the NRC Resident Inspector."

At the time of the event notification, Unit 2 was at 33 percent power. Unidentified RCS leakage is estimated at 0.28 gpm. Unit 2 is expected to be in Mode 3 by 0122 EST on 02/24/2017. Unit 1 is not affected by this event.

POTENTIAL TORNADO MISSILE VULNERABILITIES

"In order to address the concerns outlined in RIS [Regulatory Information Summary] 2015-06 'TORNADO MISSILE PROTECTION', an evaluation of tornado missile vulnerabilities and their potential impact on Technical Specification (TS) plant equipment was conducted. This evaluation concluded that the following Structures, Systems, and Components (SSCs) are potentially vulnerable to tornado generated missiles:

"The BVPS Unit 1 (BV-1) and BVPS Unit 2 (BV-2) Main Steam Safety Valve (MSSVs) discharge flow paths to atmosphere (reference TS 3.7.1) are potentially vulnerable to tornado generated missiles. A tornado could generate missiles capable of striking the exhaust piping of the MSSVs potentially crimping the piping and resulting in reduced flow capacity. In the worst case, all MSSV's could be rendered inoperable. This condition is reportable per 10 CFR 50.72(b)(3)(ii)(B), and 10 CFR 50.72(b)(3)(v)(A).

"The BV-1 and BV-2 Atmospheric Steam Dumps (ADVs) discharge flow paths to atmosphere (reference TS 3.7.4) are potentially vulnerable to tornado generated missiles. A tornado could generate missiles capable of striking the exhaust piping of the ADVs potentially crimping the piping and resulting in reduced flow capacity. In the worst case, all ADVs could be rendered inoperable. This condition is reportable per 10 CFR 50.72(b)(3)(ii)(B), and 10 CFR 50.72(b)(3)(v)(A).

"The BV-2 Auxiliary Building tornado missile shield door (A-35-5A), credited for tornado missile protection of the Primary Component Cooling Water (PCCW) system, was found to not be fully closed and latched. A tornado could generate missiles capable of striking the PCCW system with the missile door open rendering both trains of the PCCW system inoperable. This door is now maintained closed and latched except when opened under administrative controls. This condition is reportable per 10 CFR 50.72(b)(3)(ii)(B).

"The BV-2 Spent Fuel Building tornado missile shield door (F-66-3), credited for tornado missile protection of the irradiated fuel assemblies in the Spent Fuel Pool including the Cask Pit, was found to not be fully closed and latched. This door is now maintained closed and latched except when opened under administrative controls. This condition is reportable per 10 CFR 50.72(b)(3)(ii)(B).

"The potential tornado missile vulnerabilities for the MSSVs and ADVs (discussed above) are being addressed in accordance with EGM-15-002 Rev 1 and DSS-ISG-2016-01 (NRC enforcement discretion and interim guidance documents). Immediate compensatory measures were taken to reduce the likelihood and mitigate the potential consequences of an onsite tornado generated missiles.

"The NRC Resident inspector has been notified."

AGREEMENT STATE REPORT - LOST I-125 SEED

The following information was provided by the State of California via email:

"On 02/23/17, the RSO [Radiation Safety Officer] contacted RHB [California Radiologic Health Branch] to report a lost I-125 seed with an activity of 0.388 mCi. Licensee stated that three lead pigs each with an I-125 seed (0.303 mCi and 0.388 mCi from February 22nd and a 0.388 mCi I-125 seed from February 8th) believed to be accidentally thrown in Mission Bay Hospital general waste. When this was discovered, licensee contacted Recology, requested an urgent pickup of their waste compactor container at Recology site on 02/23/17. Digging through the waste, licensee was able to locate two of the three lead pigs (both from February 22nd). The pig containing 0.388 mCi I-125 from February 8th was not recovered and believed to be buried in the landfill. UCSF [University of California, San Francisco] was getting seeds from Oncura, [which] was recently bought out by Theragenics. UCSF medical physicists were accustomed to receiving just the patient seeds. Theragenics, the new vendor, had included an additional calibration seed in a separate led pig in the same package and physicist were not looking for this additional seed.

"RHB will be following up on the corrective actions."

CA 5010 Number: 022317

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