Slurry fracture injection (SFI) involves placement of solid wastes and water wider fracture pressures into deep geological formations. Currently, materials permitted for SFI include oily waste sand, "slops", produced muds, and produced water or waste water. Five years field experience has led to a good understanding of the SFI technology, and a regulatory frame- work is evolving in Alberta to permit SFI projects to proceed in an environmentally secure manner to meet the goals of the regulatory bodies as well as the goals of the oil companies.
The approach to SFI operations is described, including geological arguments related to environmental security. Security is also based on careful regulatory control, design, site selection, and analysis. The application of SFI to other waste streams should help mitigate environmental issues for heavy oil development, as well as for other oil feld applications.