The Center for Biological Diversity, an environmental group based in Arizona, filed suit against Interior Secretary Ken Salazar on Monday, alleging the U.S. government negligently assessed effects of a potential oil spill.

In a press release detailing the lawsuit, the center’s oceans director, Miyoko Sakashita, says that the risks of offshore drilling weren’t properly examined in the past: “While Salazar’s conclusion that exploration drilling in the Gulf posed little risk of a large oil spill was dubious at the time it was made, in light of BP’s calamity that position is completely untenable. … The public deserves disclosure and a full analysis of the true impacts of oil drilling off our coasts.”

According the the center, all oil drilling currently taking place in the gulf is reliant upon “assumptions made in 2007 that oil spills would not put endangered species at risk.” In a 2007 Oil-Spill Risk Analysis published by the Department of the Interior’s Minerals Management Service, the liklihood of a spill seriously affecting endangered species was dubbed “extremely low.”

But Sakashita doesn’t place all the blame on the Interior Department. In the June 26 press release, she said that statements made by the president were also incorrect: “Like Obama’s April 2 statement that ‘oil rigs today generally don’t cause spills,’ the administration’s assumption that the largest possible oil spill was 15,000 barrels — less than one day of oil spilled from the ruptured BP well — has been proven absurd by the Gulf oil disaster.”

The lawsuit claims that Salazar must be held liable for failing to uphold the Endangered Species Act, which requires that the actions of all federal agencies must not “jeopardize a threatened or endangered species.” Threatened species like Kemp’s Ridley sea turtles, sperm whales and bluefin tuna are all at a heightened risk due to the spill, which has released more than 11 million gallons of oil into the Gulf of Mexico.

This is the sixth lawsuit the center has filed regarding the gulf oil spill.