Geothermal developments must follow regulations and guidance from the Environment Agency to ensure that groundwater is not impacted by drilling or operations. At first, a pilot hole is drilled approximately 30” wide and 11m deep and cased with a steel cylinder, to stabilise the top of the well. Air is used to extract the debris, so no fluid is injected or extracted. The next section of the well is then drilled to approximately 900m. In this section, clean water is used to lubricate the drill bit and no water is extracted from the ground at these depths; therefore, borehole water supply is never depleted. As drilling continues, the well is cased with more steel and cement to around 3,000m, effectively sealing of the entire well from ground water and preventing any possible interaction of well fluid with groundwater.