Sch 20 para 4
(1) If either of the parties to an appeal, matter or question expresses a wish to appear before and be heard by the appointed person, the appointed person shall give both of them an opportunity of appearing and being heard. (2) Whether or not a party to an appeal, matter or question has asked for an opportunity to appear and be heard, the appointed person— (a) may hold a local inquiry or other hearing in connection with the appeal, matter or question, and (b) shall, if the Secretary of State so directs, hold a local inquiry in connection with the appeal, matter or question, but this sub-paragraph is subject to sub-paragraph (3) below. (3) No local inquiry shall be held by virtue of this Schedule in connection with an appeal under— (a) section 42B(5) of the Control of Pollution Act 1974, (b) section 22(5), ... or 78T(3) of the Environmental Protection Act 1990, or (c) section 191B(5) of the Water Resources Act 1991, or (d) regulation 53 of the Environmental Permitting (England and Wales) Regulations 2016 (S.I. 2016/1154) , ;... (d) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (e) regulation 55(1)(o) or (p) of the Environmental Authorisations (Scotland) Regulations 2018. (appeals against decisions that information is not commercially confidential), or any matter involved in such an appeal, and any hearing held by virtue of this Schedule in connection with any such appeal or matter must be held in private. (4) Where an appointed person holds a local inquiry or other hearing by virtue of this Schedule, an assessor may be appointed by the Secretary of State to sit with the appointed person at the inquiry or hearing and advise him on any matters arising, notwithstanding that the appointed person is to determine the appeal, matter or question. (5) Subject to paragraph 5 below, the costs of a local inquiry held under this Schedule shall be defrayed by the Secretary of State.