This issue is extremely complex; however, a few recent articles are worth reading if interested.
A Q&A story found at nature.com gives an excellent background on the issue, including notes on similar actions in other countries. Read it before taking in some stories on both sides.
Urging a victory for the EPA is Marlo Lewis Jr. In his essay for RenewAmerica you'll find the familiar conservative buzz words: consumer choice, less competition, more expensive, government authority and hopeless cause.
I couldn't find such an engaging point of view from a single source in support of the lawsuit, so here are stories about the amicus briefs filed on behalf of the National Wildlife Federation and marine conservation advocates.
Don't feel you have to read all at once. This story is going to be around for a long time.