The subsea structures to be removed need to be checked for Naturally Occurring Radioactive Materials (NORM). Material should be classified as potential NORM containing if the measurement is greater than 0.23 μSv/hr.
The options for processing NORM can vary from country to country and currently there is no adequate regulation on the issue. The regular waste management companies cannot discard NORM regular equipment to decontaminate them.
A recommended concept is to process NORM sediments and scale using dedicated maceration and grinding machinery to reduce the particle size. The resulting slurry would then be transported to an offshore facility and injected into a designated NORM disposal well. The selected subsurface structure(s) would ensure that NORM waste is injected and contained in an isolated zone, thereby preventing migration.