35 Ill. Adm. Code 681.200
Facility Classification
Section 681.200 Facility
Classification
Community water supply facilities
are classified as follows:
a)
A Class A community water supply means
any surface
water community water supply and any community water supply that includes
coagulation, lime softening, ultraviolet disinfection, membrane filtration
(including reverse osmosis), or sedimentation as part of its primary treatment
.
[415 ILCS 45/5.1]
b)
A Class B community water supply means any community water
supply that includes filtration (other than membrane filtration), aeration and
filtration (other than membrane filtration), or ion exchange equipment as a
part of its primary treatment
, and is not a Class A community water supply.
[415 ILCS 45/5.1] Facilities with aeration but without filtration or ion
exchange are not considered Class B facilities.
c)
A Class C community water supply means any community water
supply that uses chemical feeding
, and is not a Class A or Class B
community water supply. [415 ILCS 45/5.1]
d)
A Class D community water supply means any community water
supply that has pumpage, storage, or distribution
facilities, and is not a
Class A, Class B or Class C community water supply. [415 ILCS 45/5.1]