On 9/30/05, Rowan Companies of Houston, TX reported to the licensee that two generally-licensed slurry density
gauges sank along with the drilling rig they were installed on due to Hurricane Rita. The rig was abandoned prior to the hurricane's approach and so the event date is an estimate. The rig is the Rowan Odessa owned by Rowan Companies. The rig was located at Ship Shoal 250 (distance offshore and depth of water not provided). Rowan Companies performed aerial searches of the area in an attempt to find the rig.
Both gauges are Halliburton 10-SD gauges with Cs-137 sources manufactured by Isotope Products. The first device has serial number V32-0246 with a current source activity of 11.11 milliCuries (source serial number DB-076). The second device has serial number W2C-097 with a current source activity of 9.4 milliCuries (source serial number DB-140).
The licensee notified NRC Region 4 (J. Whitten).