The Trump administration’s chief environmental regulator signaled a coming showdown with California, warning the state won’t dictate the future of ambitious automobile fuel economy regulations enacted by the Obama administration.

Despite pressure from biodiesel producers to require greater minimum production levels of biomass-based diesel, the U.S. Environmental Protection Agency has stuck to its proposed plan to maintain the 2018 level of 2.1 billion gallons for 2019.

Whatever federal authorities may or may not do to alter parts of the U.S. Phase 2 regulation of greenhouse gases from trucks, California will keep regulations in place that are at least as tough as the October 2016 final rule, and might even get more strict and encompass aspects of nitrogen oxide emissions.

A notice from the U.S. Environmental Protection Agency to revisit parts of the Phase 2 final rule on greenhouse gas emissions from heavy- and medium-duty trucks isn’t likely to create changes quickly, as the agency has not presented plans for expedited action and environmental groups are vowing to pursue a challenge in a federal appeals court — once the case is no longer being held in abeyance.

Comments on a plan by the Trump administration to halt the future growth of biomass-based diesel fuel and reduce the short-term requirements for all renewable fuels were largely split down the middle, pro and con.

In a move to respond to concerns by the trailer and glider industry, the U.S. Environmental Protection Agency announced it plans to “revisit” its Phase 2 provisions on greenhouse gas emissions and fuel efficiency for medium- and heavy-duty engines.

The EPA has proposed cutting back on the minimum required volume of renewable fuels produced in 2018 and putting the brakes on the minimum volume of biomass-based diesel produced in the United States in 2019.

Users of Bestpass transponders to pay tolls are now able to use the same transponder to participate in Help Inc.’s Prepass truck weigh station bypass service.