The following information was received via email:
On October 16th 2018, The ExxonMobil RSO at the Billings Montana Refinery (License # 25-03375-01) notified USNRC of one (1) device (insertion type nuclear gauge) that failed to function as designed (10 CFR 30.50.Section B.2).
Device Information: Ohmart device, model MT-93-439-001 with 10 mCi. of Cs-137; S/N: 0692GK; Source capsule model: A-2102 (X38/2); Manufacture date: Nov 7th, 1994
Upon locking out the nuclear gauge at approximately 11:00am, the nuclear gauge user identified that the cable connecting the source capsule housing (torpedo) to the source holder retrieval mechanism had become detached. The source capsule housing appears to be in its normal operating location at the bottom of the equipment guide tube in the boot of the vessel, however, due to the disconnected cable it cannot be retrieved. The following precautionary measures were taken to ensure minimal potential for exposure (1) no vessel entry permits will be issued for the vessel (2) the area around the boot was barricaded to restrict entry.
There is no additional risk of radiation exposure to members of the general public or radiation workers due to the failure of the equipment function.
The source capsule housing is scheduled to be retrieved, shielded, and shipped for transfer to
QSA Global by
VEGA Americas, Inc. on 10/18/18."