Event Notification Report for November 23, 2020

This material event contains a "Less than Cat 3" level of radioactive material.

AGREEMENT STATE REPORT - STOLEN CPN MOISTURE / DENSITY GAUGE

The following information was received via E-mail:

"The Radiation Safety Officer (RSO) for Empire Geotechnical reported that his CPN nuclear gauge was stolen from the back of his pickup truck sometime overnight between 2100 EDT on October 28, 2020 and 0630 PDT on October 29, 2020.

"CA Dept. of Public Health Radiologic Health Branch (RHB) inspector contacted the Empire Geotechnical RSO by phone and confirmed the RSO left his truck parked on the street in front of his office with the gauge secured in the rear of the pickup under a locked deck lid. The RSO is in the process of reporting the theft to the Orange Police Department.

"The gauge is a CPN MC1DR, [serial] number MD90204854, that contains two special form sealed sources: 370 MBq (10 mCi) of Cs-137 and 1.85GBq (50 mCi) of Am-241/Be."

California 5010 Number: 102920
Cal OES control number: 20-6025, October 29, 2020

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

EN Revision Imported Date: 11/23/2020

EN Revision Text: BOTH TRAINS OF SALT WATER INOPERABLE

"At 0011 EST on 11/03/20, it was discovered that BOTH trains of salt water were simultaneously INOPERABLE. While in a planned [limiting condition for operation] LCO window with the 21 salt water train INOPERABLE for post-maintenance testing, debris intrusion in the 22 salt water header rendered the redundant salt water train INOPERABLE.

"Due to this INOPERABILITY, the system was in a condition that could have prevented the fulfillment of a safety function; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v).

"One train of salt water was restored to operable at time 0026 EST.

"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."

This event did not affect Unit 1.

* * * RETRACTION ON 11/20/2020 AT 1218 EST FROM BRIAN FOVEAUX TO OSSY FONT * * *

"Following the eight hour 10 CFR 50.72 notification made on 11/03/2020 (EN 54979), further engineering analysis determined that 22 Saltwater subsystem flow remained at levels sufficient to fulfill its safety function based on the conditions existing at the time of the event. Despite flow in 22 Saltwater subsystem falling below the short term (four hour) minimum value for approximately 15 minutes, engineering analysis was able to determine the increased heat removal capacity associated with the lower bay temperatures was sufficient to offset the reduced heat removal capacity associated with the lower 22 Saltwater subsystem flow. This demonstrated that actual heat transfer to the saltwater subsystem was sufficient to ensure all safety functions were fulfilled during the event.

"Therefore, this event notification is being retracted as it is not reportable pursuant to 10 CFR 50.72(b)(3)(v)(A), (B) and (D).

"The NRC Resident has been informed."

Notified R1DO (Greives)