for safe, clean, fast & cost- effective classification of waste
The problem
Classification of nuclear waste requires knowledge of the nature of the contamination prior to its disposal. Monitoring of surfaces provides a measure of surface contamination and remote gamma mapping gives indicative data but concrete, brick and metal surfaces must be sampled to allow detailed characterisation for radioactive contamination, heavy metals and asbestos. This often involves drilling, scraping and swabbing of surfaces releasing contamination and creating a hazard for the operator. The process is slow, dirty and inefficient, and creates significant secondary waste which must be cleared away following sampling. Most conventional tools are manually operated, and while some radiological monitors can be remotely deployed, they are not robust, subject to damage from high radiation fields and can’t easily be operated in difficult to access areas. Once collected, the samples are sent off-site for analysis in a handful of analytical laboratories able to receive radioactive material. Consignment of samples off site is expensive, laboratory turnaround times can be slow and it may be many months before data is available.
The solution
Lasers are used routinely in nuclear decommissioning, particularly for surface cleaning and removal of contaminated concrete. Laser sampling uses a lower power laser to gently remove a small amount of material from a surface without changing its chemical properties. The whole process is fast, clean, resulting in little damage to the sampled surface. A laser sampler attached to a remotely operated vehicle can be deployed in highly radioactive areas, in confined spaces or at height. Material is collected in a form ready for analysis, so in-situ characterisation becomes a reality using portable instrumentation for radiological, chemical and asbestos analysis, with results available in minutes.