Effective Radiological Contamination Control and Monitoring Techniques in High Alpha Environments
K. C. Funke
In the decommissioning of a highly contaminated alpha environment, such as the one at Hanford's Plutonium Concentration Facility (PCF), one of the key elements of a successful radiological control program is an integrated safety approach. This approach begins with the job-planning phase where the scope of the work is described. This is followed by a brainstorming session involving engineering and craft to identify how to perform the work in a logical sequence of events. Once the brainstorming session is over, a Job Hazard Analysis is performed to identify any potential problems. Mockups are utilized to enable the craft to get hands on experience and provide feedback and ideas to make the job run smoother. Ideas presented during mockup are incorporated into the task instruction. This paper describes not only the job planning aspects of this highly successful decommissioning operation, but also details the techniques used to control the spread of contamination and to minimize the generation of airborne contamination. Principal evaluation tools include lapel and workplace air sampling, plus continuous air monitors and frequent surveys to effectively monitor job progress. In this highly contaminated alpha environment with contamination levels ranging from 0.3 Bq cm-2 to ~100 kBq cm-2 with average working levels between 1600-3200 Bq cm-2 without concomitant ambient radiation levels, control of the spread of contamination is key to keeping airborne levels As Low As Reasonably Achievable (ALARA).
This abstract was presented at the 35th Annual Midyear Meeting, "Decommissioning and Environmental Restoration", Controlling Dose I Session, 2/17/2002 - 2/20/2002, held in Orlando, FL.