Section 406.205  Contact with Disturbed Areas

The Agency must consider whether the operator's practices stop or minimize water from coming into contact with disturbed areas by considering erosion controls, including:

a)         Diversions

1)         Bypass diversions that collect and convey water around or through disturbed areas to receiving stream waters that would otherwise flow over or through disturbed areas.

2)         On-site diversions that convey water around or over disturbed areas or undermined areas connected to the surface.

3)         Interception diversions that isolate on-site critical areas, including raw spoils, partially stabilized spoils, and highway access roads.

b)         Runoff Controls

1)         Clearing, grubbing, scalping, grading and reclamation to keep stages of the mining operation concurrent with extraction operations and to allow only a minimum disturbed surface area to be exposed at any one time.

2)         Keeping gradients and inclines to the active pit as short as possible to minimize the amount of drainage going to the active pit.

3)         Soil stabilization measures such as revegetation and mulching to reduce the potential for exposing materials that may produce dissolved solids.

4)         Sealing boreholes acting as conduits allowing uncontrolled entrance of water to underground mines or to active pit areas of surface mines.

5)         Leaving sufficient barriers whenever mining adjacent to abandoned underground workings that may be inundated with water.

6)         Prompt disposal of potential contaminant-producing materials in areas that will prohibit or minimize contact with surface and groundwater.

7)         Covering or treating potential contaminant-producing materials to minimize adverse effects on water quality.

8)         Sealing water-yielding fracture zones encountered during underground mining to reduce the flow of high total dissolved solids waters when geologic conditions permit successful sealing and when the flow from the fracture zone contributes significantly to the total dissolved solids load in the mine discharge.

(Source:  Amended at 43 Ill. Reg. 11620, effective September 25, 2019)