56. The undertaker shall repay to Nexus all reasonable fees, costs, charges and expenses reasonably incurred by Nexus—
(a)in constructing any protective works under the provision of paragraph 51(3) including, in respect of any permanent protective works, a capitalised sum representing the cost of maintaining and renewing those works;
(b)in respect of the employment or procurement of the services of any inspectors, supervisory staff, signalmen, watchmen and other persons whom it shall be reasonably necessary to appoint for inspecting, monitoring, signalling, watching and lighting railway property and for preventing, so far as may be reasonably practicable, interference, obstruction, danger or accident arising from the construction or failure of a specified work and to ensure the continued safe and economic operation of the railway undertaking of Nexus (including any relocation of works, apparatus and equipment necessitated by a specified work) and the comfort and safety of passengers;
(c)in respect of any special traffic working resulting from any speed restrictions which may, in the reasonable opinion of the engineer, require to be imposed by reason or in consequence of the construction or failure of a specified work, or from the substitution or diversion of services which may be reasonably necessary for the same reason;
(d)in respect of any additional temporary lighting of railway property in the vicinity of a specified work, being lighting made reasonably necessary by reason or in consequence of the construction or failure of a specified work; and
(e)in respect of the approval by the engineer of plans submitted by the undertaker and the supervision by him of the construction of a specified work.