RODEO (KPIX 5) -- Investigators are still trying to figure out how two large oil sheens near Phillips 66's Rodeo refinery ended up in the San Pablo Bay.
The oily water was discovered earlier this week near the Phillips 66 refinery in Rodeo and the public is growing increasingly frustrated with the lack of information being released regarding the oil spill
The U.S. Coast Guard hasn't found any new oil sheens in the bay, but they're still no closer to finding out where the oil spill came from.
Two days after the Coast Guard found two sheens on San Pablo Bay, authorities still don't know how big the oil spill is, who did it and why it happened.
The focus is on the Phillips 66 refinery in Rodeo.
A coast guard chopper spotted one of the sheens near a tanker that was unloading crude oil to the refinery.
U.S. Coast Guard spokesman Brandyn Hill said they believe the sheen initially reported has dissipated or evaporated.
That's the smoking gun, but the Coast Guard says there's no direct evidence pointing to the vessel for the spill.
In fact, they haven't discovered any leaks from the vessel.
Phillips 66 has since shut down operations at the dock so Coast Guard divers can investigate the under-belly of the oil tanker.
Hill said they're looking for anything that links the sheen to the oil tanker.
The Phillips 66 refinery in Rodeo has been in violation of the Clean Air Act since 2013, according to the U.S. Environmental Protection Agency's website.
A strong odor Tuesday night in Vallejo sent about 120 people to the hospital for things like headaches and dizziness.
The Coast Guard says they don't have scientific evidence to link the odor to the sheens.
The public isn't waiting around to point the finger at the oil spill.
Greg Karras with Communities for a Better Environment said, "As a common sense matter, yeah, this oil spill hurt people's health - immediately and acutely - and lots of people."
The oil tanker is owned by TK Shipping and came from Saudi Arabia last month and arrived in the San Pablo Bay this week.
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