35 ILCS 200/11-160
Applications for approval as a qualifying water treatment facility that are filed prior to January 1, 2020 shall be filed with the Department of Natural Resources in the manner and form prescribed by the Director of National Resources. The application shall contain appropriate and available descriptive information concerning anything claimed to be entitled to tax treatment as defined in this Division 4. If it is found that the facility meets the definition, the Director of Natural Resources, or his or her duly authorized designee, shall enter a finding and issue a certificate that requires tax treatment as a qualifying water treatment facility. The effective date of a certificate shall be on January 1 preceding the date of certification or preceding the date construction or installation of the facility commences, whichever is later.
35 ILCS 200/11-160