IDAPA 58.01.13.203
Design Criteria For Containers That Confine Process Water
Vats, tanks, or other containers that are partially buried and cannot be visually inspected must have a system providing secondary containment and leak detection. If visual inspection is possible and an area for secondary containment equal to one hundred ten percent (110%) of the largest container is provided, a double liner is not required. (3-24-22)