US lawIllinoisRegulationsTitle 35 — ENVIRONMENTAL PROTECTIONCHAPTER II: ENVIRONMENTAL PROTECTION AGENCYPart 370 — ILLINOIS RECOMMENDED STANDARDS FOR SEWAGE WORKSSubpart F370.63035 Ill. Adm. Code 370.630Pre-AerationLast amended: 1997Year: 2026Length: 17 wordsOfficial source Section 370 Section 370.630 Pre-Aeration Pre-aeration of sewage to reduce septicity may be required in special cases.Previous35 Ill. Adm. Code 370.620