| 406.100 | Preamble | |
| 406.101 | Averaging | |
| 406.102 | Sampling, Reporting and Monitoring | |
| 406.103 | Background Concentrations | |
| 406.104 | Dilution | |
| 406.105 | Commingling of Waste Streams | |
| 406.106 | Effluent Standards for Mine Discharges |
| 406.108 | Non-Point Source Mine Discharges | |
| 406.109 | Effluent Standards for Coal Mine Discharge from Reclamation Areas | |
| 406.110 | Alternate Effluent Standards for Coal Mine Discharges During Precipitation Events | |
| 406.201 | Temporary Exemption from Section 406.105 (Repealed) | |
| 406.202 | Violation of Water Quality Standards | |
| 406.203 | TDS Related Permit Conditions (Repealed) | |
| 406.204 | Good Mining Practices | |
| 406.205 | Contact with Disturbed Areas | |
| 406.206 | Retention and Control of Exposed Waters | |
| 406.207 | Control of Discharge Waters | |
| 406.208 | Unconventional Practices | |
| 406.209 | Expiration of Former Exemptions (Repealed) |
| a) | Part 406 applies to mine discharges and non-point source mine discharges as defined by Section 402.101. |
| b) | Other discharges, including sanitary sewers, are regulated under Subtitle C, Chapter I: Water Pollution. |
| c) | A facility which has another discharge will be subject to both Subtitle C and Subtitle D. Subtitle D governs mining activities, including mine discharges and non-point source mine discharges. Subtitle C governs other discharges. |
| d) | Except to the extent provided in this Part 406, Part 304 of subtitle C is inapplicable to mine discharges and non-point source mine discharges. |
| (Source: Amended at 32 Ill. Reg. 14978, effective September 8, 2008) | |
| a) | Compliance with the numerical standards of this part shall be determined on the basis of 24-hour composite samples averaged over any calendar month. In addition, no single 24-hour composite sample shall exceed two times the numerical standards prescribed in this part nor shall any grab sample taken individually or as an aliquot of any composite sample exceed five times the numerical standards prescribed in this part. |
| b) | Subsection (a) of this section notwithstanding, if a permittee elects monitoring and reporting by grab samples as provided in Section 406.102(f), then compliance with the numerical standards of this part shall be determined on the basis of three or more grab samples averaged over a calendar month. In addition, no single grab sample shall exceed two times the numerical standards prescribed in this part. |
| c) | The numerical standards for settleable solids are maximum values not to be exceeded at any time and are not subject to averaging. |
| d) | The numerical standards for pH shall be within the specified range at all times and are not subject to averaging. |
| a) | Where treatment is provided for a discharge, effluent samples shall be taken at a point after the final treatment process and before entry into or mixture with any waters of the state. |
| b) | Where treatment is provided the permittee shall design or modify structures so as to permit the taking of effluent samples by the Agency at the required point. |
| c) | Where treatment is not provided for a discharge, effluent samples shall be taken at the nearest point of access to the discharge source at a point where the discharge leaves the mine or mine area or other portions of the affected land, but in all cases effluent samples shall be taken before entry into or mixture with waters of the state. |
| d) | At a reasonable frequency to be determined by the Agency, the permittee shall report the actual concentration or level of any parameter identified in the state or NPDES permit. Each report submitted pursuant to this subsection shall include at least three samples taken from each pond discharge during three separate periods occurring during that reporting period in which the alternate limitations for precipitation events of Section 406.109 and 406.110 were in effect. If such alternate limitations are in effect on fewer than three separate occasions during a reporting period, one sample shall be taken of each pond discharge during each occasion in that period when the alternate limitations are in effect. The operator shall have the burden of proof that the discharge or increase in discharge was caused by the applicable precipitation event. |
| e) | The Agency may by permit condition require monitoring and reporting on the basis of 24-hour composite samples averaged over calendar months. However, grab samples or composite samples of shorter duration may be permitted by the Agency after demonstration that such samples reflect discharge levels over standard operating conditions. |
| f) | Subsection (e) of this Section notwithstanding, if a permittee so requests, the Agency shall by permit condition require monitoring and reporting on the basis of grab samples, in which case Section 406.101(b) will apply. |
| g) | Monitoring as required in this rule shall continue after abandonment until the permittee has reasonably established that drainage complies with and will continue to comply with the requirements of the Act and this Chapter. |
| h) | All methods of sample collection, preservation and analysis used in applying any of the requirements of this Chapter shall be in accord with the United States Environmental Protection Agency's current manual of practice or with other procedures acceptable to the United States Environmental Protection Agency and the Agency. |
| a) | Dilution of an effluent from a treatment works or from any wastewater source is not acceptable as a method of treatment of wastes in order to meet the effluent standards set forth in this Subpart. Rather, it shall be the obligation of any person discharging contaminants of any kind to the waters of the state to provide the best degree of treatment of wastewater consistent with technological feasibility, economic reasonableness and sound engineering judgment. |
| b) | In making determinations as to what kind of treatment is the best degree of treatment within the meaning of this Section, the following will be considered; |
| 1) | What degree of waste reduction can be achieved by process change, improved housekeeping and recovery of individual waste components for reuse; and |
| 2) | Whether individual process wastewater streams should be segregated or combined. |
| c) | Concentrations measured for the purpose of determining compliance with Section 406.106 shall be recomputed to exclude the effect of any dilution that is improper under this Section. |
| a) | The effluent limitations contained in 35 Ill. Adm. Code 304 shall not apply to mine discharges or non-point source mine discharges. |
| b) | Except as provided in Sections 406.109 and 406.110, a mine discharge effluent shall not exceed the following levels of contaminants: |
| Constituent | Storet Number | Concentration |
| Acidity | 00435 | (total acidity shall not exceed total alkalinity) |
| Iron (total) | 01045 | 3.5mg/l |
| Lead (total) | 01051 | 1 mg/l |
| Ammonia Nitrogen (as N) | 00610 | 5 mg/l |
| pH | 00400 (range 6 to 9) | |
| Zinc (total) | 01092 | 5 mg/l |
| Fluoride (total) | 00951 | 15 mg/l |
| Total suspended solids | 00530 | 35 mg/l |
| Manganese | 01055 | 2.0 mg/l |
| 1) | The ammonia nitrogen standard is applicable only to an operator utilizing ammonia in wastewater treatment. |
| 2) | The manganese effluent limitation is applicable only to discharges from facilities where chemical addition is required to meet the iron or pH effluent limitations. The upper limit of pH shall be 10 for any such facility that is unable to comply with the manganese limit at pH 9. The manganese standard is not applicable to mine discharges which are associated with areas where no active mining, processing or refuse disposal has taken place since May 13, 1976. |
| c) | New source coal mines shall be subject to a total iron limitation of 3.0 mg/1 in addition to the requirements of subsection (b) above. |
| Section 406.109 | Effluent Standards for Coal Mine Discharges from Reclamation Areas |
| a) | The effluent limitations contained in 35 Ill. Adm. Code 304 and Section 406.106 shall not apply to mine discharges from reclamation areas. |
| b) | A mine discharge effluent from a reclamation area shall not exceed the following levels of contaminants: |
| Constituent | Number | Storet
Concentration |
| Settleable solids | 0.5 ml/l | |
| pH | 00400(range 6-9) |
| c) | Notwithstanding (b), above, any discharge, or increase in the volume of discharge caused by precipitation within any 24 hour period greater than the 10-year, 24-hour precipitation event (or snowmelt of equivalent volume) shall be subject only to a pH limitation (range 6-9). |
| Section 406.110 | Alternate Effluent Standards for Coal Mine Discharges During Precipitation Events |
| a) | Discharges of alkaline mine drainage (except discharges from underground mines that are not commingled with other discharges eligible for these alternate limits), discharges from mountaintop removal operations, discharges from steep slope areas, and discharges from coal preparation plants and plant associated areas, except for drainage from coal refuse disposal piles are eligible for alternate effluent limitations during precipitation events. Any discharge or increase in the volume of a discharge caused by precipitation within any 24-hour period less than or equal to the 10-year, 24-hour precipitation event (or snowmelt of equivalent volume) may comply with the following limitations instead of those in 406.106(b): |
| Constituent | Storet Number | Concentration |
| Settleable solids | 0.5 ml/l | |
| Iron (total) | 01045 3.5 mg/l | |
| pH | 00400(range 6-9) |
| b) | Discharges of acid or ferruginous mine discharge from coal refuse disposal piles are eligible for alternate effluent limitations during precipitation events. Any discharge or increase in the volume of a discharge caused by precipitation within any 24-hour period greater than the 1-year, 24-hour precipitation event and less than or equal to the 10-year, 24-hour precipitation event (or snowmelt of equivalent volume) may comply with the following limitations instead of those in 406.106(b): |
| Constituent | Number | Storet
Concentration |
| Settleable solids | ml/l | |
| pH | 00400(range 6-9) |
| c) | Discharges of acid or ferruginous mine drainage (except for discharges in subsection (b), above, mountaintop removal areas, steep slope areas, controlled surface mines discharges and discharges from underground workings): |
| 1) | caused by precipitation within any 24 hour period less than or equal to the 2-year, 24-hour precipitation event (or snowmelt of equivalent volume) may comply with the following limitations instead of those in 406.109(b): |
| Constituent | Number | Storet
Concentration |
| Settleable solids | ml/l | |
| pH | 00400(range 6-9) |
| 2) | Caused by precipitation within any 24 hour period greater than the 2-year, 24-hour precipitation event but less than or equal to the 10-year, 24-hour precipitation event shall be subject to the requirements of subsection (c)(1), above, except for the total iron effluent standard. |
| d) | All discharges mentioned in (a), (b), and (c) of this section, discharges of acid or ferruginous mine drainage from underground workings which are commingled with other discharges and controlled acid or ferruginous surface mine discharges caused by precipitation within any 24 hour period greater than the 10-year, 24-hour precipitation event (or snowmelt of equivalent volume) shall be subject only to a pH limitation (range 6-9). |
| a) | Practices which may stop or minimize water from coming into contact with disturbed areas (Section 406.205); |
| b) | Retention and control within the site of waters exposed to disturbed materials (Section 406.206); |
| c) | Control and treatment of waters discharged from the site (Section 406.207); |
| d) | Unconventional practices (Section 406.208). |
| a) | Diversions |
| 1) | Bypass diversions to collect and convey around or through to a receiving stream waters that would otherwise flow over or through disturbed areas. |
| 2) | On-site diversions to convey water around or over: disturbed areas; or, undermined areas connected to the surface. |
| 3) | Interception diversions to isolate on-site critical areas, including, but not limited to: raw spoils, partially stabilized spoils and highway access roads. |
| b) | Runoff Controls |
| 1) | Staging of clearing, grubbing, scalping, grading and reclamation operations so that the various stages of the mining operation are kept concurrent with extraction operations, and a minimum disturbed surface area is exposed at any one time. |
| 2) | Keeping gradients and inclines to the active pit as short as possible in order to minimize the amount of drainage going to the active pit. |
| 3) | Soil stabilization through measures such as revegetation and mulching to reduce the potential for exposing materials which may produce dissolved solids. |
| 4) | Sealing of boreholes acting as conduits which allow the 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) | Disposal of potential contaminant producing materials as soon as possible in areas that will prohibit or minimize contact with surface and groundwater. |
| 7) | Covering or treating potential contaminant producing materials so as to minimize adverse effects on water quality. |
| 8) | Sealing of 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. |
| a) | Erosion Controls: grading, sloping and revegetation of disturbed soil surfaces to reduce and detain runoff. |
| b) | Sedimentation Controls: routing and segregation or combination of wastewater and mine runoff water to minimize any effect on the quality of the receiving stream. |
| c) | Reuse of Discharges: Reuse of water bearing high concentrations of total dissolved solids, whenever possible, including: |
| 1) | Recirculation ponds to recycle water to the preparation plant. |
| 2) | Recirculation ponds to provide water for underground dust control. |
| 3) | Holding ponds to provide irrigation waters to reclaimed land and/or adjacent crop land with tolerances to accept higher concentrations of total dissolved solids. |
| d) | Minimum Exposure of Waters to Disturbed Materials: |
| 1) | Application of water management practices, either continuously or at frequent intervals, in order to minimize water contact with disturbed materials. |
| 2) | Prevention of accumulation of waters in active pits, benches, terraces, roads, processing areas, surface depressions and underground mine workings and cavities where the dissolution of contaminants will be facilitated. |
| 3) | Removal of water to diversions and appropriate impoundments as soon as possible to minimize additional loadings of total dissolved solids. |
| a) | Regulation of discharges when other control methods are insufficient and chemical treatment is economically unfeasible, including: |
| 1) | Regulating the flow of discharges high in total dissolved solids in accordance with fluctuating or intermittent stream flows so that the concentration of total dissolved solids remains within established water quality standards; or |
| 2) | Regulating the flow or fluctuation of receiving streams by timely discharge of water from existing impoundments which have suitable discharge control structures. |
| b) | Rerouting over economically feasible distances, involving collecting discharges and conveying them to more suitable discharge points, such as large holding ponds located adjacent to more suitable receiving streams where dilution and/or water quality is better. |
| a) | Diversion of groundwater by intercepting the flow path prior to entering a surface or underground mine when it is determined by the mine operator to be economically preferable to treating contaminated water after it passes through a mine. |
| b) | Dewatering practices that remove clean formation water before contacting dissolved solids-producing materials, including techniques which can be employed to tap nonpolluted aquifers in order to reduce the amount of water entering a mine. |
| c) | Any additional practices which the operator demonstrates to be effective in reducing levels of total dissolved solids, chloride, sulfate, iron and manganese in discharges. |
| Chapter 4, Mine Related Pollution Part VI, Effluent and Water Quality Standards | 35 Ill. Admin. Code Part 406 |
| Rule 600 | Section 406.100 |
| Rule 601 | Section 406.101 |
| Rule 602 | Section 406.102 |
| Rule 603 | Section 406.103 |
| Rule 604 | Section 406.104 |
| Rule 605 | Section 406.105 |
| Rule 605.1 | Section 406.201 |
| Rule 606 | Section 406.106 |
| Rule 607 | Section 406.107 |
| Rule 608 | Section 406.108 |