Section 406.102  Sampling, Reporting and Monitoring

a)         When treatment is provided for a discharge, effluent samples must be taken after the final treatment process and before entry into or mixture with any waters of the State.

b)         The permittee must design or modify structures that allow effluent samples at the required point. When treatment is not provided for a discharge, effluent samples must be taken at the nearest point of access to the discharge source at a point where the discharge leaves the mine, mine area, or other portions of the affected land.  All effluent samples must be taken before entry into or mixture with waters of the State. 

c)         The Agency will determine a reasonable frequency at which the permittee must report the actual concentration or level of any parameter identified in the State or NPDES permit. 

1)         Each report submitted under this subsection (c) must 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 under Sections 406.109 and 406.110 were in effect. 

2)         If alternate limitations under Sections 406.109 and 406.110 are in effect on fewer than three separate occasions during a reporting period, one sample must be taken from each pond discharge on each occasion during that period when the alternate limitations are in effect.  The operator has the burden of proof that the applicable precipitation event caused the discharge or increase in discharge.

d)         The Agency may require monitoring and reporting based on 24-hour composite samples averaged over calendar months as a permit condition.  The Agency may permit grab samples or composite samples of shorter duration after the permittee demonstrates that the samples reflect discharge levels over standard operating conditions.

e)         Despite subsection (d), if a permittee requests, the Agency may require monitoring and reporting based on grab samples as a permit condition, in which case Section 406.101(b) will apply.

f)         Monitoring must 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 Subtitle D.

g)         All methods of sample collection, preservation and analysis used in applying  the requirements of Subtitle D must be in accord with USEPA's current practice manual or other procedures acceptable to USEPA and the Agency.

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