Section 217.152  Compliance Date and 30-Day Rolling Average Basis

a)         On and after July 1, 2025, the owner or operator of an emission unit subject to the requirements of this Subpart and Subpart E, F, G, H, I, or M must comply with the requirements of the applicable Subparts.  Compliance with emissions limitations must be on a 30-day rolling average basis.  A 30-day rolling average consists of 30 operating days where an operating day is a calendar day in which any affected emission unit combusts any fuel.  Compliance with the 30-day rolling average must be demonstrated 30 operating days after July 1, 2025.

1)         A 30-day rolling average under Subparts E, F, I, and M is calculated using the total mass of emissions from the period and the total heat input from such period.

2)         A 30-day rolling average under Subparts G and H is calculated using the total mass of emissions from the period and the total amount of glass, clinker, or lime produced in the period.

b)         The owner or operator of an emission unit that is constructed or modified on or after July 1, 2025, and that is subject to this Subpart and Subpart E, F, G, H, I, or M must comply with the applicable Subparts within 180 days after initial startup of the new or modified emission unit.

c)         Notwithstanding subsection (a) of this Section, compliance with the requirements of Subpart G of this Part by an owner or operator of an emission unit subject to Subpart G of this Part is extended until December 31, 2014, if the unit is required to meet emissions limitations for NO_x, as measured using a continuous emissions monitoring system, and included within a legally enforceable order on or before May 7, 2010, whereby the emissions limitations are less than 30 percent of the emissions limitations under Section 217.204.

d)         Notwithstanding subsection (a) of this Section, the owner or operator of emission units subject to Subpart E or F of this Part and located at a petroleum refinery must comply with the requirements of this Subpart and Subpart E or F of this Part, as applicable, for those emission units beginning January 1, 2015, except that the owner or operator of emission units listed in Appendix H must comply with the requirements of this Subpart, including the option of demonstrating compliance with the applicable Subpart through an emissions averaging plan under Section 217.158 and Subpart E or F of this Part, as applicable, for the listed emission units beginning on the dates set forth in Appendix H.  With Agency approval, the owner or operator of emission units listed in Appendix H may elect to comply with the requirements of this Subpart and Subpart E or F of this Part, as applicable, by reducing the emissions of emission units other than those listed in Appendix H, if the emissions limitations of those other emission units are equal to or more stringent than the applicable emissions limitations set forth in Subpart E or F of this Part, as applicable, by the dates set forth in Appendix H.

e)         Notwithstanding subsection (a) of this Section, the owner or operator of emission units subject to Subpart F and located at a petroleum refinery listed in Appendix I that first become subject to the emission limitations under Subpart F on July 1, 2025, must comply with the applicable limitations in Subpart F, including the option of demonstrating compliance with the applicable Subpart through an emissions averaging plan under Section 217.158, for such emission units beginning on and after the dates set forth in Appendix I.

f)         Before January 1, 2028, the provisions of Section 217.152(a) that are effective on and after July 1, 2025, do not apply to (1) the three natural gas boilers numbered 6AP, 7AP, and 8AP located at the source located at 100 Abbott Park Road in Lake County, and (2) the two natural gas boilers numbered 9 and 12 located at the source located at 1401 Sheridan Road in Lake County.

g)         Notwithstanding subsection (a) of this Section, the owner or operator of emission units subject to Subpart E or Subpart F and located at a petrochemical facility listed in Appendix I that first become subject to the emission limitations under Subpart E or F on July 1, 2025, must comply with the applicable limitations in Subpart E or F, including the option of demonstrating compliance with the applicable Subpart through an emissions averaging plan under Section 217.158, for such emission units beginning on and after the dates set forth in Appendix I.

(Source:  Amended at 49 Ill. Reg. 6355, effective April 23, 2025)