ISTR and Subsidence Risks

More and more frequently, In Situ Thermal Remediation (ISTR) is being used to treat contaminations located below buildings, roadways, and other critical infrastructure. Subsidence and potential geotechnical effects on buildings and infrastructure are concerns often raised in the initial design phase of a thermal remedy.

While the heating approach and main heating mechanisms differ based on the ISTR technology utilized, heating in general will thermally expand the soils treated and at the same time, change the saturation of the treated volume due to boil-off of some of the water. Depending on the geology, this can lead to changes in the geotechnical integrity.

In this flash webinar, the basics factors affecting the geotechnical properties during a thermal remedy will be discussed, along with a general description of soil types where subsidence is more likely to happen. Examples of geotechnical pre-investigations and tests utilized to determine the impact of a structure’s stability will be given along with case studies showing data from thermal areas remediated below structures.