Since its inception TerraDat has gained a wealth of experience providing geophysical services to the nuclear and windfarm industries. More recently our survey methods have found application within the solar industry. We have developed a suite of geophysical techniques ideally suited to the needs of most solar farm developments. On greenfield sites archaeology is often the concern while on brownfield sites buried foundations, site hazards and contaminated land are of more interest.
Archaeological (magnetic gradiometry) surveys are often required in the early stages of a solar farm development. Due to the large areas involved these surveys can be expensive and time consuming. TerraDat’s state of the art rapid archaeological acquisition system counters this, providing up to 20-40ha of high-resolution magnetic gradiometry data per day. The increased efficiency of this system is due to the use of a towed multi-sensor rig. The survey results are delivered as fully interpreted plots in CAD/GIS formats to suit.
To assist planning applications and to optimise PV layout and associated infrastructure works, a combination of magnetic, ground conductivity and microgravity surveys can be used to map underground hazards such as buried services, UXO, mine workings, solution features, and shallow obstructions. Resistivity tomography surveys are also used to provide information on the shallow geological structure but also for measuring soil electrical properties for earthing design. This approach is more accurate than the traditional 4-pin method as it is possible to derive more reliable resistivity values. Thermal properties of the soil can be analysed by using a thermal resistivity meter to acquire data either at surface, or within trial pits.
Seismic surveys are used to profile the depth and strength of shallow ground materials and can be used to calculate a range of engineering properties including rock rippability, shear and bulk modulus as required.