A fuel truck that leaked diesel fuel while driving aboard a Steamship Authority (SSA) ferry in Woods Hole caused residual delays in the boat schedule, Thursday.

According to authority communications director Sean Driscoll, the fuel truck was boarding the 9:30 a.m. ferry from Woods Hole to Vineyard Haven, when the fuel leak occurred. The truck was backed off the boat, but about five gallons of diesel fuel spilled.

“A small amount of fuel dripped into the water, causing a sheen that was approximately four feet by six feet,” Mr. Driscoll said in an emailed statement. “SSA personnel have cleaned the sheen and the landside fuel spill and the Coast Guard approved to let the vessel depart the slip.”

The 9:30 a.m. trip left about an hour late. The incident caused the authority to advise passengers there would be a half hour delay in the noon boat from Woods Hole to Vineyard Haven, and about a 15 minute delay in the scheduled 12:20 boat from Vineyard Haven to Woods Hole.

“We expect residual delays today as we try to make up the time,” Mr. Driscoll said. “We thank our customers for their patience.”

The Steamship Authority notified the federal Environmental Protection Agency’s national response center, and the Massachusetts Department of Environmental Protection of the small spill, as required by law.