s A.1 Development not permitted
(1) Development is not permitted by Class A if: (a) in the case of any Class A(d) and (f) development, any part of the line is within a European site or a site of special scientific interest; (b) (save as provided for in paragraph A.2(3)) in the case of any Class A(d), (f) or (g) development— (i) the line is to be installed in a different position from the existing line; or (ii) the height above the surface of the ground of any support for the line will exceed the height of the highest support which is to be replaced; (iii) the installation will be in a National Park or an area of outstanding natural beauty, and it is determined there is likely to be a significant adverse effect on the environment; (c) in the case of any Class A(e) development, the building in question is a scheduled monument, a listed building or in a conservation area; (d) in the case of any Class A(f) development the line has a nominal voltage greater than the nominal voltage of the existing line. (2) For the purposes of paragraph A.1(b) it is determined that there is likely to be a significant adverse effect on the environment if— (a) notice is given by the person proposing to carry out the installation to the local planning authority of that proposal; and (b) the authority, within six weeks of receiving that notice— (i) determines that if the installation were completed in accordance with the proposal it would in the opinion of that authority be likely to have a significant adverse effect on the environment; and (ii) notifies the person by whom the notice was given and the Welsh Ministers of that determination.