Modifies provisions relating to sewage disposal

This bill requires Missouri's Department of Health and Senior Services to establish state-wide soil-based standards for septic system installation and maintenance, replacing outdated rules. It defines qualified professionals (including licensed engineers, certified soil scientists, and sanitarians) who can conduct required soil evaluations and mandates a contractor registration program with continuing education requirements by 2027. Homeowners, contractors, and local governments (counties/cities) must comply with these standards, with the state enforcing them if local jurisdictions fail to adopt the rules. The law also creates training programs for contractors and requires counties to adopt the standards or risk state enforcement, with temporary percolation tests allowed until 2026.