The following information was received from the Los Angeles Radiation Management Department via facsimile:
On March 4, 2015, the Radiation Safety Officer (RSO), Exxon Mobil Oil Corporation (License #0113-19) reported to LA County Radiation Management that the shutter on one of their Thermo Nuclear gauges was not operating such that it could be completely closed per the manufacturer's design/specifications. This issue was discovered while Exxon Mobil was testing the integrity of all sources and source holders located in the area affected by the explosion that took place on February 18, 2015 (5010 #021815).
At approximately 0900 [PST], [the RSO], along with a licensed Thermo Nuclear technician discovered that the Thermo Nuclear source holder, would not close completely, despite multiple attempts by the Thermo Nuclear technician. A radiation survey was performed around the source holder and the surrounding area was taped off with caution tape. The radiation level surrounding the source holder was found to be approximately 4 mR/hr. Exxon Mobil identified the source holder as Thermo Nuclear Model 5197, S/N CN-2435, with a 100 mCi Cs-137 source (S/N B8849).
Upon discovery, [the RSO] immediately contacted LA County Radiation Management to report the findings. In addition to taping off the area, [the RSO] stated that the source is still in its normal position, approximately 10 feet from the ground and away from any routine traffic. Exxon Mobil has 24 gauges in the area that [were] impacted by the explosion on February 18, 2014. [The RSO] stated that only 11 gauges have been inspected thus far for leakage and damage. The remaining gauges will be inspected by the end of the week. Should Exxon Mobil discover another damaged source or source holder, they have been instructed to report the findings to LA County Radiation Management immediately.
California 5010 Number: 030415