US lawIllinoisRegulationsTitle 35 — ENVIRONMENTAL PROTECTIONCHAPTER I: POLLUTION CONTROL BOARDPart 501 — GENERAL PROVISIONSSubpart B501.25235 Ill. Adm. Code 501.252Frozen GroundLast amended: 2014Year: 2026Length: 25 wordsOfficial source Section 501.252 Frozen Ground Soil that is frozen anywhere between the first ½ inch to 8 inches of soil as measured from the ground surface.Previous35 Ill. Adm. Code 501.250Next35 Ill. Adm. Code 501.253