An Employee shall be entitled to no less than five dollars per hour in Premium Hazard Pay for each hour worked on-site for an Employer in the City. If an Employer already provides hourly Premium Hazard Pay as of the effective date of this ordinance, such compensation may be credited against the additional five dollars per hour required by this section. In no event shall any Premium Hazard Pay provided prior to the effective date of this ordinance be credited as part of the compensation due under this section.