Earthjustice is challenging the rule over particulate matter – tiny specks of dust and dirt that can linger in the air and become lodged in people’s lungs.

The agriculture regulation passed earlier this year requires farmers to water service roads, plant grass between trees and buy updated equipment to help cut down on dust pollution. But Earthjustice’s Paul Cort says that’s not good enough. 

"We’d like to see the rule specify emission control levels that all farms would achieve as opposed to the current structure which gives them a menu that’s so long that virtually every farm can pick something that they’re already doing to comply."

The lawsuit was filed in the Ninth US Circuit Court of Appeals.