This story was originally Appear in mother jones and is climate desk cooperate.

The saga of the USPS’ planned gas-guzzling fleet continues.

Sixteen states and two environmental activist groups—Earth Justice and the National Resource Defense Council—are suing the U.S. Postal Service to stop buying a large fleet of gas-guzzling mail vans. Postmaster General Louis DeJoy has come under fire in recent months for his decision to move forward with a contract for 165,000 new postal trucks, 90 percent of which will run on gasoline and deliver just 8.6 miles per gallon.

Environmental groups argue in the lawsuit that DeJoy did not begin an environmental review of the contract until the Postal Service made a $483 million down payment to new truck maker Oshkosh Defense. The EPA argued that the review itself was flawed.

“Electrifying the Postal Service fleet will reduce smog and particulate pollution in nearly every neighborhood in the United States,” the plaintiffs wrote. “Postal delivery routes are stop-and-go in nature, meaning gasoline-powered delivery vans are used at large during the day. Part-time idle outside people’s homes. This daily pollution affects nearly every resident in the country, but the harmful effects of this pollution are felt most acutely in low-income communities of color, who are often forced to breathe compound source of pollution.”

The 16 state attorneys general sued separately, saying the USPS plan would hinder their own environmental goals. “The Postal Service has a historic opportunity to invest in our planet and our future,” California Attorney General Rob Bonta, who oversees the state’s lawsuit, said in a statement. “Instead, it’s doubling down on outdated technologies that are bad for our environment and communities.”

In March, U.S. Representative Gerry Connolly of Virginia introduced a bill that would require the USPS to commit to a new fleet of 75 percent electric vehicles, but the proposal has yet to withdraw from the committee.

“Once the purchase is complete, we will have more than 100,000 new gas-guzzling vehicles on our community streets for the next 30 years, serving families in our state and across the country,” Bonta said. “We will go to court to ensure the Postal Service follows the law and consider greener alternatives before making this decision.”

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