Key Decision: Turbines blocked on mine subsidence
Concerns over potential subsidence have resulted in dismissal of plans to site nine turbines above a coal seam in south Wales.
The Coal Authority had granted a 99-year lease to extract coal from beneath the appeal site. The parties had no doubt that a planning application seeking consent for this development would be approved. The case centred on the extent to which the turbines would be affected by subsidence once coal extraction began.
To maximise output, the mining company proposed to use long wall mining, which would allow up to 88 per cent of the coal reserve to be mined, rather than traditional pillar and board methods, which would allow less than 25 per cent to be extracted but reduce the risk of subsidence. Under the Coal Mining Subsidence Act 1991 and the Coal Industry Act 1994, the mining operator would be liable for any subsidence caused to land or property, including the turbines.
The wind farm developers initially proposed a bilateral agreement to protect the mining company and the Coal Authority against any liability arising from subsidence of the turbines. However, counsel’s advice indicated that a court would rule that it was not possible to contract out of the provisions of the 1991 act in this way. Instead, the appellants offered a section 106 obligation.
The inspector noted that the appellants had tried to guard the mining operator against liability through the planning obligation, a deed of indemnity, an insurance policy and a power of attorney, but considered that there was still a risk that the courts would view this as circumventing statutory protection. The problem could not be overcome through a planning condition, he added.
Without agreement on an indemnity package, he reasoned, the Coal Authority would be likely to require a substantial cash deposit from the mining company if it sought to use long wall mining methods, in which case it would probably fall back on the less efficient pillar and board method. This outcome would contravene government policy that mineral resources should be protected against other development that would hinder their extraction, he concluded.
Clive Nield; Inquiry