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Planning Policy Guidance Note 8: Telecommunications makes clear that applicants for new masts should provide evidence that they have explored the possibility of erecting antennas on an existing building, mast or other structure and that such evidence should accompany any prior approval or planning application made to the local planning authority.
The Code of Best Practice on Mobile Phone Network Development sets out the supplementary information that the operators provide to accompany applications for planning permission and prior approval under part 24 of schedule 2 to the Town and Country Planning (General Permitted Development) Order 1995 (as amended). The supplementary information that is routinely submitted with applications includes a list of the alternative sites considered during the site selection process and the reasons for not choosing them. Local planning authorities can assess the adequacy of this information when determining the relevant application.
We are currently reviewing the planning procedures relating to applications for new base stations and are considering the effectiveness of the processes set out above as part of the review.