"The proposed HEISTT solution is the rapid installation of groundwater treatment chemicals as an insitu subsurface remediation technique, brought about by the use of ultrasonic assisted injection technology to create a closely spaced grid of single treatment small diameter wells to a depth of 20m. As part of the boreholing process, remediation chemicals will be introduced in to the ground contained within a geotextile sock. Diffusion of the chemicals (oxygen release compounds, hydrogen release compounds, zero-valent iron or chemical oxidants) occurs through the permeable geotextile material. Injection target cycle time will be = 5 mins from hole to hole at 1m spacing. The spacing of these boreholes will be decided by the concentration of contaminant and the required rate of clean-up. This whole system will be passive, i.e. requiring no energy to function after installation or operator maintenance. A range of equipment options are envisaged, from simple attachments for existing excavation plant � which will be the primary focus of HEISTT , enabling rapid take up of the process by SMEs due to the affordability of retrofit - through to dedicated bespoke machinery."