A 100-foot-long sailboat sank in the Oakland Estuary around 6 p.m. on Sunday, prompting concerns from locals that fuel from the boat could leak into the Bay and nearby bodies of water like Lake Merritt.

That danger seems to have been avoided, thanks to a rapid response by the Alameda Fire Department, Coast Guard, and California Department of Fish and Wildlife.

Alameda Fire Department PIO Kevin Tidwell said Tuesday morning that fire crews “stabilized the boat and made sure there was no immediate hazard or risks to the public.” This included moving nearby boats while a team of firefighters used chainsaws and other tools to cut away the section of the dock the massive sailboat was moored to. The recovery operation is now under the supervision of the Coast Guard.

The SV Kaisei had an estimated 400 gallons of diesel on board. The cause of the boat’s submergence is unknown.

The Ocean Voyages Institute, the boat’s owner, told KTVU they think something struck the SV Kaisei. The Coast Guard has yet to weigh in on the cause.

Founded in 1979, the Ocean Voyages Institute piloted the SV Kaisei to clean up trash in the Pacific Ocean, including in 2009, 2011, and 2012. But locals in Alameda say in recent years the boat doesn’t appeared to have been moved away from its dock.

On Tuesday, a crew, including divers, was working on the boat, which remains completely submerged except for its masts. A state Department of Fish and Wildlife boat idled in the water nearby to monitor the cleanup effort while small groups of people watched the operation from Alameda’s Nob Hill Foods parking lot.