Illinois Administrative Code
Title 35 - ENVIRONMENTAL PROTECTION
Part 620 - GROUNDWATER QUALITY
Subpart B - GROUNDWATER CLASSIFICATION
Section 620.240 - Class IV: Other Groundwater
Current through Register Vol. 48, No. 38, September 20, 2024
Except as provided in Section 620.250, Other Groundwater is:
a) Groundwater within the zone of attenuation as provided in 35 Ill. Adm. Code 811 and 814;
b) Groundwater within a point of compliance as provided in 35 Ill. Adm. Code 724, but not to exceed a distance of 200 feet from a potential primary or secondary source.
c) Groundwater that naturally contains more than 10,000 mg/L of total dissolved solids;
d) Groundwater which has been designated by the Board as an exempt aquifer pursuant to 35 Ill. Adm. Code 730.104; or
e) Groundwater which underlies a potential primary or secondary source, in which contaminants may be present from a release, if the owner or operator of such source notifies the Agency in writing and the following conditions are met:
f) Groundwater which underlies a coal mine refuse disposal area not contained within an area from which overburden has been removed, a coal combustion waste disposal area at a surface coal mine authorized under Section 21(s) of the Act, or an impoundment that contains sludge, slurry, or precipitated process material at a coal preparation plant, in which contaminants may be present, if such area or impoundment was placed into operation after February 1, 1983, if the owner and operator notifies the Agency in writing, and if the following conditions are met:
g) Groundwater within a previously mined area, unless monitoring demonstrates that the groundwater is capable of consistently meeting the standards of Sections 620.410 or 620.420. If such capability is determined, groundwater within the previously mined area shall not be Class IV.