Lifecycle of a well
Any exploratory operations will be undertaken in a series of phases:
- Phase 1: Wellsite Construction
- Phase 2: Drilling Operations
- Phase 3: Evaluation
- Phase 4: Decommissioning and Restoration
Generally any application submitted by IGas would be to undertake exploratory operations, with all these phases incorporated into one planning application.
Phase 1 involves consulting the wellsite and any ancillary works such as erecting the site fencing. As per standard practice, during construction an impermeable membrane is laid down to seal the wellsite. This ensures any spills or rainwaters are collected and contained within the site and then taken away for suitable disposal.
Phase 2 involves bringing the rig to site and setting up (mobilisation), then, once the wells have been drilled the removal of the rig and associated equipment off site (demobilisation.) The drill rig is a temporary structure and the ancillary equipment is only in place as long as we are drilling.
As the drill used on site will be dependent on availability, the planning application will generally assess the maximum adverse impacts in relation to particular environmental and amenity effects, such as noise, landscape and visual character, ecology, lighting and cultural heritage. The landscape assessment will account for a fully enclosed rig up to 60 m in maximum height.
Once the drilling phase is complete the wells will be suspended and made safe in accordance with the relevant regulations and industry best practice (e.g. Oil and Gas UK Guidelines for Abandonment of Wells, Issue 5, July 2015.) All above ground equipment including the drill rig and facilities will be removed from site, with the exception of:
- The wellhead (also known as ‘Christmas Tree.’)
- Site offices and security
- Fencing and gates.
IGas will then undertake the evaluation phase (phase 3.) This is when all the information gathered during the drilling phase is assessed and this will generally take between 3 and 6 months.
If the results show that there is value in further appraisal of a well, then a further application for planning permission will be submitted. This could include an application to flow-test the well, which involves conducting a small hydraulic fracture or a ‘mini frack.’
If, however, the appraisal concludes that there is no merit in any further exploration the well will be ‘plugged and abandoned’ which refers to the process of sealing the well using a process agreed by the regulators and restoring the site to a condition which is agreed by the landowner and the planning officers.