This regulation applies to C.P. Crane units 1 and 2, Chalk Point unit 2, Dickerson units 1, 2, and 3, and H.A. Wagner unit 2. General Requirements. The owner or operator of the affected electric generating units subject to this regulation shall choose from the following: Not later than June 1, 2020: Install and operate a selective catalytic reduction (SCR) control system; and Meet a NOx emission rate of 0.09 lbs/MMBtu, as determined on a 30-day rolling average during the ozone season; Not later than June 1, 2020, permanently retire the unit; Not later than June 1, 2020, permanently switch fuel from coal to natural gas for the unit; Not later than June 1, 2020, meet either a NOx emission rate of 0.13 lbs/MMBtu as determined on a 24-hour systemwide block average or a systemwide NOx tonnage cap of 21 tons per day during the ozone season. When option §B(4)of this regulation is selected: Not later than May 1, 2016, the owner or operator of an affected electric generating unit shall not exceed a NOx 30-day systemwide rolling average emission rate of 0.13 lbs/MMBtu during the ozone season. Not later than May 1, 2018, the owner or operator of an affected electric generating unit shall not exceed a NOx 30-day systemwide rolling average emission rate of 0.11 lbs/MMBtu during the ozone season. Not later than May 1, 2020, the owner or operator of an affected electric generating unit shall not exceed a NOx 30-day systemwide rolling average emission rate of 0.09 lbs/MMBtu during the ozone season. In order to calculate the 24-hour systemwide block average emission rate and systemwide NOx tonnage cap under §B(4) of this regulation and the systemwide rolling average emission rates under §C of this regulation: The owner or operator shall use all affected electric generating units within their system as those terms are defined in Regulation .01B of this chapter; and The unit or units NOx emissions from all operations during the entire operating day shall be used where the unit or units burn coal at any time during that operating day. Beginning June 1, 2020, if the unit or units included in a system, as that system existed on May 1, 2015, is no longer directly or indirectly owned, operated, or controlled by the owner, operator, or controller of the system: The remaining units within the system shall meet either: The requirements of §B(1)—(3) of this regulation; or A NOx emission rate of 0.13 lbs/MMBtu as determined on a 24-hour systemwide block average and the requirements of §C(3) of this regulation. The unit or units no longer included in the system shall meet the requirements of §B(1)—(3) of this regulation. For the purposes of this regulation, the owner includes parent companies, affiliates, and subsidiaries of the owner.