As of this afternoon, the Coast Guard had not given permission to Tesoro Hawai'i to resume unloading operations and no estimate was available as to how soon the refinery could resume pumping operations through the 16-inch line, Coast Guard Petty Officer Jennifer Johnson said.

Johnson said there is no sheen on the water and therefore no marine cleanup is needed.

Crews from the state's two oil spill response vessels, along with five support ships, worked over the weekend to clean up a 4.5-mile slick caused when up to 2,000 gallons of Tesoro light crude oil spilled 1.5 miles off Barbers Point.

The cause of the spill is under investigation by a unified command composed of the U.S. Coast Guard, Tesoro, and the state Department of Health.

Tesoro spokesman Nathan Hokama said the spill happened around midnight when a chartered oil tanker was delivering 42 million gallons of light crude to the Tesoro single point buoy that pipes the oil to the refinery. About 20 minutes into the operation one of the tanker's hose lines uncoupled.

Although the unloading operation was then halted, an estimated 1,000 to 2,000 gallons of light crude had spilled into the ocean, Hokama said.

Hokama said the Coast Guard and the Hawai'i Department of Health were immediately notified, and specialized vessels from the Clean Islands Council and the Marine Spill Response Corporation responded to the accident.