5.—(1) Subject to sub-paragraph (2), this paragraph shall apply where an application is made for the variation of the conditions of a permit under regulation 19(2) which will authorise—
(a)a substantial change in the operation of an installation or mobile plant;
(b)a variation of the conditions of a permit where regulation 13(3) applies; or
(c)a variation of the conditions of a permit in any other case where the enforcing authority determines that the procedure set out in sub-paragraph (3) should apply even though heads (a) and (b) do not apply.
(2) This paragraph shall not apply to an application for the variation of conditions of a permit in relation to an installation carrying out only dry cleaning activities as defined in sub-paragraph (2) of Part C of section 7 of Part 1 of Schedule 1.
(3) The enforcing authority shall, subject to paragraph 24(a), within the period of 14 days from the date of receiving the application—
(a)notify the operator in writing that this paragraph applies and of any fee prescribed in respect of the application for variation under regulation 25;
(b)give notice in writing of the application, enclosing a copy of it, to the persons to whom notice would have to be given in accordance with paragraph 12 of Schedule 4 in the case of an application for a permit to operate the particular installation or mobile plant;
(4) For the purpose of calculating the period of 14 days mentioned in sub-paragraph (3) no account shall be taken of any period beginning with the date on which notice is served on an operator under paragraph 4 and ending on the date on which the operator furnishes the information specified in the notice.
(5) If the applicant does not pay to the enforcing authority any fee notified under sub-paragraph (3)(a) within 28 days of the notification the application shall be deemed to have been withdrawn.