Shale gas extraction can continue at each drilling site for many years but it is the initial construction, drilling and hydraulic fracturing process that creates the main environmental impact.
Initial construction of the well takes approximately 2–3 weeks. Noise is caused by the construction activity but also from frequent movement of heavy plant and vehicles in and out of the site.
Once the well has been constructed, drilling commences and may last up to 30 days depending on well depth. The drilling process is noisy and usually continues 24 hours a day and throughout the night when surrounding communities are most sensitive to noise. Extensive measures are taken around the drilling site to reduce noise which can include, for example, a sound wall or curtain to reduce noise levels in neighbouring communities.
After drilling is complete, the hydraulic fracking process directs a high pressure water mixture into the well to fracture the rock and release gas. Fracking can take between 3–5 days and is usually limited to daylight hours. Fracking does create noise but usually at a lower level than that from drilling. Once the well is capped, everything is removed from the drilling pad and gas is drawn from the pipeline using compressors. These create some noise, which is usually successfully managed by housing the compressors in sound isolating enclosures. However, there has been noise disturbance reported where they are located close to residences.