The Cross Borehole Tomography project (XHT) is a collaboration between Boart Longyear and Roqsense Pty Ltd, supported kindly by the South Australian Department of Energy and Mining with funding through successful application and award of the Accelerated Drilling Initiative (ADI) program. Lodestone Mines has kindly offered to support new technologies on their tenements and includes in-kind contributions. The XHT project partnership was to create driller installable permanent, cross-borehole tomography sensor strings in drilled boreholes. Two types of sensor cable strings will be developed. The project envisions testing the ability to perform both active and passive imaging. Active imaging will use the drill rig to make a “signal” for the sensor strings (the drilling process of cutting the rock). Active imaging will use the drill-rig (position) to either perform cross-well tomography to an instrumented hole or be in line-with two other boreholes to perform interferometric imaging with a known source location. The sensors string records wave energy to measure physical earth properties between boreholes. Properties such as density, speed of sound, dielectric constant, electrical resistivity, and fracture density can change the phase and amplitudes of seismic/EM waves. Seismic waves are sensitive to mechanical properties of the rock and EM to electrical properties. Cross-well tomography is a process that determines the distribution of physical properties based upon the differences in wave amplitudes and phase at various combinations of points between boreholes. Key tasks in the XHT Project are to: a) Demonstrate driller deploy-ability when installing instrumentation via grouting holes b) Develop deployable and cost-effective instrumentation sensor strings in HQ (and NQ) holes c) Create cross-well tomographic (CBT) images via passive or active methods d) Demonstrate that CBT images are representative of geological changes and conditions e) Collect supporting data to assist in c) and d) The project was planned to be carried out in two phases which all include both exploration drilling and proof of concept activities. Phase 1a. Brukunga test site. Involves preparation and installation of imitation antenna/sensor cables to develop procedures in preparation for the permanent installed sensor cables. Small scale tests are carried out sending and receiving signals via scientific equipment. Phase 1b. Brukunga test site. Involves installation of the geophone sensor cables. Testing will be carried out to determine the viability of the sensor design and analysis of data of holes depth of 50 m. Phase 1c. Brukunga test site. Testing will be carried out on hole depths of 200 m. Phase 2 – Involves the installation of the technology to assess the concept in an exploration setting at Lodestone Mines Olary Project. However, due to numerous issues encountered during the project the final phase of the project was all carried out at the Brukunga site. The project work has been undertaken at the Brukunga Pyrite Mine located in the Adelaide Hills. The location has been kindly provided to Boart Longyear under licence agreement and long-standing relationship with the South Australian Department of Energy and Minerals. During the project, 7 vertical diamond cored holes were drilled for a total length of 810.7 m. Geochemistry was determined using the Boart Longyear Veracio TruScan pXRF. Despite challenges it was determined that seismic while drilling with diamond drill rigs in conjunction with geophone sensor arrays is feasible and should provide very useful life-of-mine data. The company developed methodology and instruments that allowed the drillers to install and collect tomography data. The in-line configuration of drill-rig and two instrumented boreholes was a viable means to perform cross-well tomography. Initial work found that S-wave energy to be predominant. S-waves should provide higher spatial resolution in tomography: a serendipitous outcome from the project.