This presentation will focus on the appropriate use of in-situ injections as a remedial tool for contaminated sites. It will introduce the two types of injection behaviour — permeation and fracture injection — and address the direct injection myth. The importance of injection flow rate in controlling injection mode, and how to use pressure and flow data to assess which mode is occurring, will be explained. A case history will be presented to illustrate the importance of using pressure and flow data to adjust the injection plan in the field.

We will discuss how geology, contaminant distribution, and project-specific goals impact amendment selection and the design of the injection approach.

There will also be an introduction to the use of tiltmeters to map emplaced fracture networks.

The presentation will conclude with a summary of the advantages and limitations of in-situ injections, followed by an open discussion to gather feedback and answer questions.