Sunday / Contractual Holiday Extra Duty. There shall be a separate extra duty list and rotation for all work on Sundays and Contractual Holidays, excluding field trips. If an employee declines the extra duty work, he/she must wait until his/her next turn in the rotation. If no one in the affected classification within the building where the work is located wants the extra duty, it shall be offered by seniority to staff assigned to the affected classification in other buildings. If the Sunday / Contractual Holiday Extra Duty involves custodians and/or janitors, this separate extra duty list will be implemented consistent with sub-paragraph d above.