Upon application to the local health department, a site that has existing fill, including one on which fill material was placed prior to July 1, 1977, and that has sand or loamy sand for a depth of at least 36 inches below the existing ground surface, shall be evaluated for an on-site wastewater system. The Commission shall adopt rules to implement this section. (1989, c. 764, s. 8; 1991 (Reg. Sess., 1992), c. 944, s. 7.)