Section 502.605  Livestock Waste Discharge Limitations for the Production Area for Permitted CAFOs

a)         Except as provided in subsections (a)(1), (a)(2), and (c), there must be no livestock waste discharge into the waters of the United States from the CAFO production area.  Whenever precipitation causes an overflow of livestock wastes from the containment or storage structure, livestock wastes in the overflow may be discharged into the waters of the United States if:

1)         The production area is designed, constructed, operated, and maintained to contain all livestock wastes, including the runoff and the direct precipitation from a 25-year, 24-hour precipitation event, except that, for swine, poultry, or veal, large CAFOs that are new sources must comply with Subpart H, and

2)         The production area is operated in accordance with the additional measures and records required by Section 502.610.

b)         Any point source subject to this Subpart must achieve the livestock waste discharge limitations in this Section by the permit coverage date.

c)         Voluntary Alternative Performance Standards. Any CAFO subject to this Subpart may request the Agency to establish NPDES permit livestock waste discharge limitations based upon site-specific alternative technologies that achieve a quantity of pollutants discharged from the production area equal to or less than the quantity of pollutants that would be discharged under the baseline performance standards as provided by subsection (a).

1)          In requesting site-specific livestock waste discharge limitations to be included in the NPDES permit, the CAFO owner or operator must submit a supporting technical analysis and any other relevant information and data that would support those site-specific livestock waste discharge limitations within the time frame the Agency provides.

2)          The supporting technical analysis must include calculating the quantity of pollutants discharged, on a mass basis when appropriate, based on a site-specific analysis of a system designed, constructed, operated, and maintained to contain all livestock waste, including the runoff from a 25-year, 24-hour rainfall event.

3)          The technical analysis of the discharge of pollutants must include:

A)        all daily inputs to the storage system, including livestock waste, direct precipitation, and runoff;

B)        all daily outputs from the storage system, including losses due to evaporation, sludge removal, and wastewater removal for use on cropland at the CAFO or transport off-site;

C)        a calculation determining the predicted median annual overflow volume based on a 25-year period of actual rainfall data applicable to the site;

D)        site-specific pollutant data, including nitrogen, phosphorus, BOD_5, and total suspended solids, for the CAFO from representative sampling and analyzing all sources of input to the storage system, or other appropriate pollutant data; and

E)        predicted annual average pollutant discharge, expressed, when appropriate, as a mass discharge on a daily basis (lbs/day), and calculated considering subsections (c)(3)(A) through (D).

4)         The Agency may request additional information to supplement the supporting technical analysis, including inspecting the CAFO.

(Source:  Amended at 48 Ill. Reg. 3196, effective February 15, 2024)