EPA considered several factors when developing the reporting threshold, including the form of the threshold (e.g., emissions/year, potential to emit, capacity-based, facility or unit level). EPA reviewed existing capacity-based (e.g., 25 megawatts) and emissions-based thresholds used in other GHG emissions programs (e.g., California’s 25,000 mtCO₂e) and the 10,000 mtCO₂e levels used in some voluntary programs, such as the Department of Energy’s (DOE’s) 1605b program. Based on our review, EPA has determined that the selected 25,000 metric ton CO₂e threshold will cover many of the types of facilities and suppliers typically regulated under the CAA, while appropriately balancing emission coverage and burden. EPA estimated that at a threshold of 25,000 metric tons of mtCO₂e/year, approximately 10,000 facilities and 85 percent of total GHG emissions will be covered. At the 10,000 mtCO₂e/year level, EPA found that there would be a higher economic impact on small businesses including small industrial facilities and commercial buildings.