Ill. Admin. Code tit. 35 § 602.116
If any portion of a community water supply has been constructed without a construction permit as required by Section 602.101, or an emergency permit issued under Section 602.104, the community water supply must submit to the Agency as-built plans and specifications and a construction permit application. As-built plans and specifications must be prepared by a qualified person as described in Section 602.105(a)(4). All plans and specifications submitted to the Agency under this Section must be clearly marked "as-built" or "record drawings". Any deficiencies requiring correction, as determined by the Agency, must be corrected within a time limit set by the Agency. Submission of as-built plans and the correction of any deficiencies does not relieve the owner or official custodian from any liability for construction without a permit.
Ill. Admin. Code tit. 35, § 602.116