Document LJmoRo6VXk16ojoVKnyBGp72z

21. The MATS RTR provides that Continuous Emission Monitoring Systems (CEMS) are the only method to demonstrate compliance with the fPM limit. LIGNITE COMBUSTION 22. Lignite varies in composition and the distribution of mercury within individual coal samples is not uniform, unlike other types of coals. The amount of mercury within one seam of coal can vary drastically, not to mention mercury content fluctuations between seams at the same mine.2 Minnkota's units see this large degree of variability within a 24hour operating period. See Attachment A, at Tables 2-4, 2-5. 23. An important difference between mine-mouth coal plants and typical coal-fired power plants is the control over fuel composition. Nonmine-mouth facilities purchase coal of a specified quality to be delivered to the facility. Unlike other types of facilities that may be able to blend coals to achieve greater consistency in the character of their fuel, many North LEC Comments filed June 23, 2024, htir,:hdo\vniod,ve!.2,Lildtion.i_ro\ -1:1) - I R.)-t).11: 1.pdt -9- Sierra Club FOIA 2025-EPA-04883 ED_018388_00000327-00061 SC_EVERSPLIT0006370