3.4 Rail yard-related emissions

The 2023 NEI includes estimates compiled by the EPA for most rail yards in the US. Yard emissions are associated with the operation of switcher engines at each yard. Switch yards are reported as point sources to SCC 28500201. Some states report switch yards to nonpoint (2285002010); however, EPA prefers that these emissions be reported as point sources and may be retiring the nonpoint SCC in the next NEI cycle. Details for rail yards are documented in a report, “2023 National Emissions Inventory Locomotive Methodology”, on the 2023 Supporting data FTP site. S/L/Ts submitted point rail yard emissions were compared to EPA-computed emissions to avoid double counting between the S/L/T and EPA emissions.