The private fishing boat that grounded near Monroe Landing last month spilled less than five gallons of diesel into Penn Cove.

That was the estimate given by Andy Quast, spill responder for the Washington State Department of Ecology.

Quast came up with the figure after meeting with the vessel’s owner, Rick Heppell, and calculating how much diesel remained in the fuel tanks and what was recovered from the boat’s bilge.

The boat carried two 100-gallon tanks that Quast estimated were carrying about 130 gallons of fuel combined.

The initial concern was that the spill was worse.

“It was actually pretty minimal,” Quast said of the amount that escaped into Penn Cove.

The smell of diesel prompted a nearby resident to call North Whidbey Fire and Rescue on July 26 and begin an emergency response that led to the department setting about 700 feet of boom several feet from the shore to contain any fuel that might’ve leaked from the beached vessel.

The U.S. Coast Guard, Island County Health Department and Vessel Assist out of Port Hadlock all responded to the incident and the Oak Harbor Fire Department and City of Oak Harbor Marina also played roles.

The boat was freed later that night at high tide.

“It was a great result for everyone involved,” Quast said.

The 32-foot vessel had been tied up to a buoy offshore near the Captain Whidbey Inn in Coupeville before the rope broke, sending the boat adrift.