Event Notification Report for November 06, 2018

AGREEMENT STATE REPORT - GAUGE LOST AND THEN FOUND

The following information was received from the Commonwealth of Kentucky by email:

"On 11/6/2018, a former licensee [formerly licensed as Wickliffe Paper Co.] reported discovery of a nuclear gauging device (TN [Texas Nuclear] model 5036 originally containing 200 mCi assayed 12/94) that it was unaware it possessed. The license was terminated on August 9, 2016 and at that time, the former licensee provided information related to the disposition of all devices the licensee was aware it possessed. License termination was due to plant closure. During engineering surveys to assess plant conditions for restart, personnel discovered the device still mounted on plant equipment. The former licensee is taking steps to have the device transferred to a licensed manufacturer for disposal. There is no reason to believe any individuals received any exposure at levels which would exceed the regulatory limits."

Kentucky Event: KY180004

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

AGREEMENT STATE REPORT - DAMAGED MOISTURE DENSITY GAUGE

The following was received via email from the State of Texas:

"On November 6, 2018, the licensee notified the Agency [Texas Department of State Health Services] that one of its Troxler model 3411 moisture/density gauges had been damaged at a temporary work site. The gauge contains an 8 milliCurie Cesium - 137 source and a 40 milliCurie Americium source. The initial report stated the casing and electronics were damaged but the shielding and insertion rod were not damaged.

"The licensee's Radiation Safety Officer (RSO) stated that at approximately 1430 [CST] on November 6, 2018, one of their technicians was working at a temporary job site. He had left the Troxler model 3411 moisture/density gauge on the ground about 10 feet behind him while he was preparing the test hole. A front end loader came into the area and struck the gauge with its back tire. The outer casing/shell of the device was broken as were the electronics. The source had been inside the gauge at the time. The insertion rod did not appear to be bent (didn't push it out to make sure), the shielding was not damaged, and survey did not detect any radiation above the same levels when sources are known to be fully shielded. The gauge was placed inside its transport case and transported to the licensee's facility for storage. The RSO stated the gauge would be taken to the service company for repair or disposal.

"On November 7, 2018, the Agency contacted the RSO and requested a picture of the device. The Agency received the pictures later that day. The Agency reviewed the pictures and the insertion rod for the cesium source appeared to have a slight bend in it. The Agency sent an e-mail request to the RSO and asked if the rod was operable.

"On November 8, 2018, the RSO responded to the Agency and stated they had not operated the source rod and he believed it would not be operable because of a slight curving bend in the operating rod. The gauge is still in storage at the licensee's location. The Agency will not ask the licensee to try and operate the rod as there is the risk that the source could get stuck in an unshielded position.

"Additional information will be provided as it is received in accordance with SA-300."

Texas Incident #: I-9630

PART 21 REPORT - RESIDUAL HEAT REMOVAL SYSTEM MOTOR OPERATED GLOBE VALVE EXPERIENCED STEM FAILURES

The following was received via e-mail:

"This notification is being submitted pursuant to the guidelines of 10 CFR Part 21 to report that a 24in Class 150 Globe valve for RHRSW HX [Residual Heat Removal Service Water Heat Exchanger] Isolation MOV [motor operated valves], E1150F068B at Detroit Edison - Fermi 2, experienced two stem failures.

"The site notified WVC USA [Weir Valves and Controls, USA] on November 6 of this issue involving two stems. WVC USA had supplied these stems on orders 20000262-10 and 20012001-10, Detroit Edison PO's [part orders] 4700505700 and 4701149217. A new stem failed after approximately 1 month in service in valve F068B. A replacement stem was installed and failed soon after being placed in service. This second stem failure had previously been in service for approximately three years while installed in sister valve F068A. Both stem breakages occurred at the transition area of the stem backseat and were visually identical. See pictures of failure in Attachment A. In the as found condition, the disc to stem connection appears to have lacked design clearances. The cause of this clearance issue was cleaning of the disc surface where the disc nut is tack welded. The material supplied is A276 410 heat treated and tempered to obtain (269-311 BHN). This material was approved by Powell as an acceptable alternate to the original material A182 F6 (269-311 BHN). During original Part 21 evaluation, testing of the stem material revealed low impact values and reflected effects of temper embrittlement. Other possible contributors to the failure were transition region at stem backseat and the valve service conditions where vibration due to throttling has been experienced. It was determined that although temper embrittlement and other factors may have contributed to the failures, that the lack of design clearance led to the failure of the stems and was not reportable by WVC USA. However, after discussions with Detroit Edison, WVC USA was requested to evaluate the failure considering the effects of temper embrittlement that might lead to future failures.

"WVC USA engineering is unable to determine the effects of temper embrittlement for the A276 410 material. Powell engineering was also consulted and there are no known methods to evaluate the potential for failure on the stem in this condition. As noted in NRC Information Notice No. 85-59, tempering in the 700 degrees F to 1050 degrees F range is not recommended because it results in low and erratic impact properties and poor resistance to corrosion and stress corrosion for 410 stainless steel.

"The stem failures in this case reflected these low and erratic impact properties based on material testing that was performed by DTE [Detroit Edison] Fermi and WVC USA. The A276 410 materials supplied in this event were tempered at 1025 degrees F and 1050 degrees F.

"The best solution is to eliminate the potential for temper embrittlement by using a higher required tempering temperature. The recommendation is to use A276 410 tempered at a minimum of 1100 degrees F. This is also in alignment with Code Case N-62-7. We are in the process of updating our item records to reflect this minimum tempering requirement and expect this action to be completed within one month.

"WVC USA is notifying the following sites of this potential issue so that they can evaluate the impact on the safe operation of the plant.

"74347-10 Entergy PO 10118969 Site Grand Gulf
Item Number P 26126666ASSEMAO_QLA Stem & Disc Assy 14" Qy (1) Shipped 7/28/06

"0020005433-10 Georgia Power Company PO SNG10081312 REV. 2 Site Hatch
Item Number P0000419C Stem/Disc Assy 24-300 Globe Valve Qty (1) Shipped 10/29/15

"0020006979-10 Detroit Edison Company PO 4700846295 Site Fermi 2
Item Number P0000455C Stem Bin Gate Valve Qty (1) Shipped 6/29/15

"0020011676-10 Detroit Edison Company PO 4701123403 Site Fermi 2
Item Number P0000455C Stem Bin Gate Valve Qty (1) Shipped 2/14/18

"0020013251-10 Detroit Edison Company PO 4701230062 Site Fermi 2
Item Number P0000283 Stem Globe 24in 150# Qty (1) Shipped 9/19/18

"0020013586-10 Detroit Edison Company PO 4701259926 C0#6 Site Fermi 2
Item Number P0000283 Stem Globe 24in 150# Qty (1) Shipped 11/13/18

"Stem supplied under order 0020013251-10 is currently installed in F068A and order
0020013586-10 was delivered but not installed. F068B valve has been restored by Detroit
Edison with a stem which has acceptable properties for the service."

The above Part 21 notification affects Grand Gulf, Fermi 2, and Hatch.

Point of Contact: Allen Fisher
Director of Engineering
978-825-8451
allen.fisher@mail.weir