GB-Swindon: UKRI-1436 Requirement for geophysical logging and sampling

The aim of this logging and sampling exercise is to provide pre-injection logging data and then logging data and pressurised fluid samples following small-scale CO2 injection at a field laboratory in Leicestershire during Late February - mid March 2021. Geophysical logs are expected to show changes in electrical properties as the CO2 dissolves into the pore water, making it slightly more acidic. These geophysical results will be validated through analysis of collected fluid samples that will confirm the concentration of CO2 in each well. There are four monitoring wells with plastic Boode casing, ID 76.6 mm, OD 90 mm. This casing has slots to access the sandstone at depths of around 180 m and 205 m. CO2 will be injected into this sandstone via a dedicated injection well and will migrate through natural pathways in the sandstone. The sandstone is capped by a thick mudstone. These wells are filled with groundwater, almost to surface.