The US Environmental Protection Agency is ratcheting back US production of hydrofluorocarbons (HFCs), which are extremely potent greenhouse gases, and is proposing that two chemical plants destroy an HFC made as a byproduct.
A regulation that administrator Michael S. Regan signed Sept. 23 implements a 2020 law that mandates the phasedown of HFC production in the US to 15% of 2011–13 average levels by 2036.
The EPA projects that the reduction of emissions from 2022 to 2050 will be equivalent to 4.6 billion metric tons of carbon dioxide.
Separately, the EPA is proposing a regulation that specifically targets HFC-23, or fluoroform, which is generated as a byproduct at plants making hydrochlorofluorocarbons (HCFCs). HFC-23 has a “substantially longer” lifetime in the atmosphere and a higher global warming potential than any other HFC, the EPA says. The regulation would require chemical manufacturers to control, capture, and destroy HFC-23.
Like the rest of the world, the US is phasing out the production and use of HCFCs, which both deplete stratospheric ozone and are greenhouse gases. But there is an exception. Companies are allowed to manufacture HCFCs as feedstocks that are entirely consumed, except as trace quantities, in the production of other chemicals.
The EPA’s proposal would allow facilities to emit a maximum of 0.1% of the HFC-23 generated during production of HCFCs as of Oct. 1, 2022. The agency says the proposal would only affect two chemical manufacturing plants. The EPA’s Facility Level Information on Greenhouse gases Tool indicates these are Chemours’s facility in Louisville, Kentucky, and Daikin America’s plant in Decatur, Alabama. These two facilities reported HFC-23 emissions from the manufacture of HFCs in 2019, the most recent year for which data are available, the tool shows.
In concert with EPA’s actions, the US Department of Homeland Security is beefing up efforts to prevent illegal imports of HFCs.
President Joe Biden has called for the US to join a 2016 pact that controls HFCs, the Kigali Amendment to the 1989 Montreal Protocol on Substances that Deplete the Ozone Layer. The US signed the deal but is not an official partner to it because the Senate has not yet consented to formal ratification of the treaty.