made for office expense, office supplies or stationery, bookkeeping, financing, or any other overhead accounts. Rental rates other than O.P.S.S. rates must be approved by the Engineer.

ii. The charges for equipment used by the Contractor will be made on the actual number of hours on which the equipment is actively engaged in the extra work. If a unit of equipment is not performing its normal function for a period of time exceeding one hour, it will be on standby time from the time it ceased performing its normal function, provided that the unit of equipment is fully operable and cannot practically be used on other work but must remain on the site in order to continue with its assigned task. This time, together with actual working time will only be paid up to the period of time which constitutes one working day. Payment, if any, for additional gaps must be negotiated and approved by the Engineer. The City will pay the operator or operating crew on an hourly rate for the length of standby, plus 25% of the scheduled equipment rental rate for the machine while standing by.