The owner or developer of property at which any construction requiring the issuance of a building permit is performed shall provide portable toilet facilities at the construction site for use by persons working at the site if permanent sanitary facilities are not available to the workers at the site. In the case of a multi-lot development, portable toilet facilities need not be made available on each lot if such facilities are located within 500 feet of each lot. The person responsible for complying with this Section shall comply with all federal and state laws prescribing the number of and accessibility to the portable toilet facilities required to be provided under this Section. That person shall also provide that such facilities shall be locked or otherwise secured when the construction site is unsupervised.