On January 10, 2007, a Notice of Violation was issued for a Severity Level III violation involving the failure, on two separate occasions, to provide a minimum of two independent physical controls that form tangible barriers to secure portable gauges from unauthorized removal when not under the control and constant surveillance of the licensee. Specifically, on September 21, 2006, a portable nuclear gauge was not secured within an unlocked company vehicle; and, a second gauge was not secured within a locked storage shed.