Event Notification Report for December 04, 2020

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

AGREEMENT STATE REPORT - FIXED GAUGE SHUTTER MALFUNCTION

The following information was received from State of New Jersey via email:

"The licensee reported on 11/24/20 that during a 6-month shutter check, one Cs-137 (50 mCi) fixed gauge shutter was found to be not closing completely. The gauge manufacturer was contacted and came on site to fix the shutter. Leak tests were taken before and after and found to be under 0.005 æCi. More information will be provided by the licensee."

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

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

AGREEMENT STATE REPORT - DAMAGED MOISTURE DENSITY GAUGE

The following information was received from the state of Massachusetts via email:

"MA RCP [Radiation Control Program] Officer received notification from the licensee Radiation Safety Officer (RSO) that one of their portable gauges was damaged by construction equipment at a temporary job site of the licensee.

"The portable gauge is a Troxler Electronics Laboratories Model 3400 Series moisture-density gauge containing up to 9 milliCurie of Cesium-137 in one sealed source and up to 44 milliCurie of Americium-241 in another sealed source.

"The RSO reported that they were in route to the site with a survey instrument and that, based on information received by his technician at the site, the damage is expected to be minor. The RSO indicated the portable gauge was in use at the time of the incident. The gauge and rod were pushed into the sand when the damage occurred. The RSO indicated his technician told him the shielding was intact, however, the source and shielding separated from the plastic portion of the gauge. He also indicated the source was able to be retracted into the gauge's shielding. Additionally, RCP dispatched personnel to the site to perform surveys and evaluation of the gauge.

"RCP staff evaluated NRC reporting requirements. Equipment was secured on-site. No loose contamination identified and maximum dose rate was 20 mR per hour at contact on the shielded source holder. No personnel exposure and there was no immediate threat to public health. No additional emergency response was required. RCP personnel assisted in boxing the damaged gauge and the licensee will return the gauge securely to their office and will then arrange for transport back to the manufacturer. RCP will follow up with additional information."

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

VALID ACTUATION OF AN EMERGENCY DIESEL GENERATOR

"At 0923 EST on December 3, 2020, with Unit 1 in Mode 1 at 100 percent power, an actuation of the Emergency AC Electrical Power System (Emergency Diesel Generator 1A) occurred during normal plant operations. The reason for Emergency Diesel Generator 1A auto start was due to Class 1E 4KV Bus 11 feeder breaker opening.

"The Emergency Diesel Generator 1A automatically started as designed when the loss of voltage signal on 4KV Bus 11 was received. This event is being reported in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that resulted in a valid actuation of the Emergency AC Electrical Power System.

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

The cause of the 4KV Bus 11 Feeder Breaker opening is unknown at the present time and is under investigation.