Document gb3DrRwoevdj6Nqgzxr0rqOjJ

USCA Case #24-1287 Document #2077531 Filed: 09/30/2024 Page 17 of 81 are near numerical MACT floors (i.e., the marginal passes category described above). SunCoke has data showing that many of its facilities are meeting the new MACT floor limits, but not with a comfortable margin of error. a. For example, in June of 2017, a trial was conducted on the main stack of SunCoke's facility, MTO, to ascertain its PAH emissions. The Final Rule's MACT floor for main stack PAH emissions is 4.80E-07 gr/dscf. Here are the measurements that were obtained from the trial: (1) 3.05E-07, (2) 4.48E-07, and (3) 3.16E-07. The test result was 3.56E-07, which is 74% of the MACT floor limit. So if the Final Rule were in effect in 2017, MTO would have passed--but only marginally. This is only one example of a marginal pass. 41. SunCoke is uncomfortable operating anywhere close to the edge of noncompliance. Correcting all marginal passes in all SunCoke's facilities--based on the limited data currently available--could require expenditures of up to $260,000,000. 42. If testing reveals that additional controls are needed for emissions that currently appear to satisfy the MACT floor limits (i.e, the (Page 17 of Total) - 17- Sierra Club FOIA 2025-EPA-04883 ED_018388_00000109-00116 SC_EVERSPLIT0005790