Disposal of radioactive wastes by slurry fracture injection

Slurry fracture injection is used in Saskatchewan and Alberta to dispose of inert, low-toxicity fine-grained oily quartzose sand and oily water. This waste disposal method can be extended to low-level, large-volume radioactive solid wastes with reasonable cost and low environmental risk; all technical factors seem favorable. Some of the geotechnical and monitoring issues related to large-volume emplacement of wastes are discussed in this article. Stress alterations and fracture orientation changes occur during solids injection. Injection processes are monitored using wells and the induced displacement field. Most sedimentary basins have favourable characteristics for implementation of slurry fracture injection; with proper site selection and slurry design, million-year security seems entirely reasonable. (author)