Ill. Admin. Code tit. 35 § 671.102
"Act" means the Environmental Protection Act (Ill. Rev. Stat., 1987, ch. 1111/2, pars. 1001 et seq., as amended).
"Agency" means the Illinois Environmental Protection Agency.
"Certified professional geologist" means a person certified by the American Institute of Professional Geologists.
"Confined aquifer" means an aquifer bounded above and below by impermeable beds or by shale, clay, or siltstone.
"Drawdown" means the change in the water elevation of the static water level produced by a pumping well.
"Normal operational conditions" mean capability of a well at or under the safe yield rate.
"Professional judgment" means the use of those engineering principles and practices used by engineers when fulfilling their requirements of this Part and as certified by a Professional Engineer licensed under the Illinois Professional Engineering Act (Ill. Rev. Stat. 1987, ch. 111, par. 5101 et seq.), or the use of those geologic principles and practices used by geologists when fulfilling their requirements and duties consistent with the specific requirements of this Part and as certified by a certified professional geologist who is a member of the American Institute of Professional Geologists (7828 Vance Drive, Suite 103, Arvada, Colorado 80003, January 17, 1988).
"Registered professional engineer" means a person registered under the provisions of the Illinois Professional Engineering Act (Ill. Rev. Stat. 1987, ch. 111, par. 5101 et seq.).
"Safe yield rate" means the rate (in gallons pumped per minute per foot of drawdown) at which water can be withdrawn from an aquifer without depleting the supply.
"Unconfined aquifer" means an aquifer other than a confined aquifer.
Ill. Admin. Code tit. 35, § 671.102