The Department of Ecology, Coast Guard and U.S. Oil are responding to a diesel fuel spill in Tacoma's Blair Waterway Tuesday afternoon.

The DOE said during a fuel transfer, a U.S. Oil employee found a leak on a partially open bleeder valve. The valve was closed and the transfer was halted.

Observations on the waterway showed that less than 25 gallons of diesel fuel spilled from the shore side into the Blair Waterway.

An oil containment boom located at the dock was deployed and spill response crews are working to contain the spill.

An investigation is under way to determine the exact cause of the spill and the amount of diesel fuel spilled.

No injuries have been reported.

The waterway remains open, but vessel traffic should avoid wakes and stay away from the cleanup area as much as possible.