77 Ill. Adm. Code 860.530
Existing Communities
Section 860
Section 860.530 Existing
Communities
For existing communities,
alterations shall not be required on items that were previously accepted by the
Department, unless such items create a significant health or safety problem. A
significant health or safety problem may include conditions such as improper
sewage disposal, contaminated drinking water, unsafe electrical systems, or the
location of existing auxiliary structures.