WASHINGTON (CN) — Environmentalists on Wednesday updated their court battle to stop the sale of what they call “fatally flawed” oil and gas drilling leases at risk of causing a blowout or catastrophic oil spill.

The supplemental complaint filed in U.S. District Court accuses the Bureau of Ocean Energy Management of failing to properly assess safety regulations and royalty rates on new leases.

“It is critical that BOEM accurately assess the effects of oil and gas exploration, development, and production likely to result from a lease sale at the lease sale stage,” the complaint states, “because that is the last opportunity the agency has to adjust the number or locations of blocks it offers for lease to avoid unacceptable environmental impacts.”

President Donald Trump ordered federal agencies in 2017 to overhaul all policies and regulations that could slow the development of domestic fossil fuels. The directive triggered the Interior Department to repeal many critical safety provisions for offshore development.

“Against this backdrop, Interior has begun to execute an unprecedented oil and gas leasing program in the Gulf of Mexico,” the complaint states.

The rollback on safety and environmental protection — including the Obama-era Well Control Rule and the Clean Power Plan — comes amid increased drilling in recent years in deeper waters where pressure and temperatures are higher, escalating the risk of explosions.

Among other changes, regulators have eliminated required improvements to blowout preventers, the key piece of equipment on the Deepwater Horizon drilling rig, whose failure in April 2010 caused an explosion that killed 11 and contaminated the Gulf with more than 100 million gallons of oil.

“This lease sale is coming just a month shy of the 10-year memorial of the BP Deepwater Horizon disaster and at a time of global crisis,” Brettny Hardy, an attorney with Earthjustice, said in a statement Wednesday. “It is yet another example of the Trump administration putting profits before the health and safety of people and the planet.”

Nearly 2,000 platforms pumping oil and gas already spot the Gulf of Mexico, with 2,500 total active leases. Any given year, the region sees at least 2,100 oil and chemical spills.

The Gulf is home to 23 marine species and two coastal bird species listed as endangered or threatened, and produces one-third of the nation’s seafood supply. Fisheries and tourism generate more than $40 billion annually in economic activity in the five Gulf Coast states.

But the Bureau of Ocean Energy Management, according to the complaint, based new lease sales on “incorrect and illogical assumptions, fatally undermining the analyses,” the result being that federal regulators “significantly underestimate and otherwise misjudge and misstate the effects that a lease sale in the Gulf of Mexico will have on the human and natural environment.”

The environmental advocacy groups are now looking to U.S District Judge Reggie Walton in Washington to vacate three lease sales, each of which could result in up to 767 new development and production wells, and between 355 and 2,144 kilometers of new pipelines.

“BOEM did not explain how drilling hundreds of new wells and installing supporting infrastructure on the one hand will have the same environmental effects as preventing these activities on the other hand,” the complaint states.

The Environmental Protection Agency declined to comment on the pending litigation. Attorneys for the environmental groups did not respond to requests for comment by publication.