Two derelict boats began sinking in the Hylebos Waterway early Friday morning and spilled a small amount of oil into the waterway.
According to the Washington Department of Ecology, the derelict vessels Helena Star and Golden West were tied together at Mason Marine when the Helena Star began sinking and pulling the other vessel down with it.
The Tacoma Fire Department placed oil containment boom around both vessels to prevent possible pollution from any residual fuel remaining inside the vessels.
Ecology and the U.S. Coast Guard are working with Ballard Diving and Salvage to contain the spilled oil.
The state is also investigating a report of four or five birds that may have gotten into oil.
In March 2012, about 20,000 gallons of oil and oily water as well as other hazardous substances were removed from the vessels, limiting the potential for pollution to the waterway.
Ballard Diving and Salvage, an environmental cleanup contractor, is placing secondary boom around the vessels and working to clean up some pockets of diesel fuel in the waterway. Most of the cleanup is expected to be completed today, with continued monitoring by Ecology and the Coast Guard over the next couple of days. There are no plans to untie the vessels or raise them at this time.