EPA has issued a final rule to amend provisions in the diesel sulfur fuel programs to provide necessary flexibility for transmix processors and pipeline operators who produce locomotive and marine diesel fuel.. The diesel transmix amendments will reinstate an allowance for transmix processors and pipeline operators to produce 500 ppm sulfur diesel fuel for use in older technology locomotive and marine diesel outside of the Northeast Mid-Atlantic (NEMA) Area and Alaska after 2014.
As background, these provisions were originally put in place as a necessary flexibility to address feasibility and cost issues associated with handling of the transmix volume generated in the pipeline distribution system. These provisions allowed the fuel distribution system to continue to function while transitioning to ultra-low sulfur diesel fuel (ULSD). The technology to economically reduce the sulfur content of transmix distillate product to 15 ppm at transmix processor and pipeline facilities did not exist, and any alternative measures of disposing of transmix were likewise deemed infeasible or cost prohibitive as the market was then configured. Thus, in order to implement the ULSD regulations, an outlet for the consumption of transmix distillate product was necessary. With no outlet, transmix would build up in storage tanks and pipelines would need to cease operations. When the ULSD standards were expanded to nonroad, locomotive, and marine (NRLM) diesel fuel, this would have removed the sole outlet in most areas of the country.