9.—(1) Subject to the following provisions of this paragraph, the undertaker must pay to the statutory undertaker in question the reasonable expenses incurred by that statutory undertaker in, or in connection with, the inspection, removal, alteration or protection of any apparatus.
(2) The value of any apparatus removed under this Part is to be deducted from any sum payable under paragraph 9(1), that value being calculated after removal.
(3) If in accordance with this Part—
(a)apparatus of better type, of greater capacity or of greater dimensions is placed in substitution for existing apparatus of worse type, of smaller capacity or of smaller dimensions; or
(b)apparatus (whether existing apparatus or apparatus substituted for existing apparatus) is placed at a depth greater than the depth at which the existing apparatus was,
and the placing of apparatus of that type or capacity or of those dimensions or the placing of apparatus at that depth, as the case may be, is not agreed by the undertaker or, in default of agreement, is not determined by arbitration in accordance with article 84 (arbitration) to be necessary, then, if such placing involves cost in the construction of works under this Part exceeding that which would have been involved if the apparatus placed had been of the existing type, capacity or dimensions, or at the existing depth, as the case may be, the amount which apart from this sub-paragraph would be payable to the statutory undertaker in question by virtue of paragraph 9(1) is to be reduced by the amount of that excess.
(4) For the purposes of sub-paragraph (3)—
(a)an extension of apparatus to a length greater than the length of existing apparatus is not to be treated as a placing of apparatus of greater dimensions than those of the existing apparatus; and
(b)where the provision of a joint in a cable is agreed, or is determined to be necessary, the consequential provision of a jointing chamber or of a manhole is to be treated as if it also had been agreed or had been so determined.
(5) An amount which apart from this sub-paragraph would be payable to a statutory undertaker in respect of works by virtue of paragraph 9(1) must, if the works include the placing of apparatus provided in substitution for apparatus placed more than 7 years and 6 months earlier so as to confer on the statutory undertaker in question any financial benefit by deferment of the time for renewal of the apparatus in the ordinary course, be reduced by the amount which represents that benefit.