A state water agency has proposed fining a Rodeo oil refinery nearly $500,000 for releasing millions of gallons of toxic wastewater into San Pablo Bay that killed fish.

ConocoPhillips discharged between 2.5 million gallons and 7.6 million gallons on seven occasions from January 2008 to May 2008, according to a California Regional Water Quality Control Board complaint filed last week. The releases flowed into San Pablo Bay through an outfall pipe during high rain days., violating fish toxicity limits. The board has proposed a $490,000 fine.

"The volume involved is significant," said David Clegern, a state spokesman. "When you're dealing with more than one million gallons of something, you're dealing with a lot of water. In all of these cases, you're dealing with more than two million gallons of water."

The wastewater likely contained naphthalic acids, byproducts from processing petroleum which are harmful for fish. Testing found dead rainbow trout, the water agency reported.

"It was not a huge kill as far as we know, but it was toxic," Clegern said. "If trout are affected, then potentially hundreds of other organisms could be affected in the Bay."

The refinery, which treats about 2.7 million gallons of wastewater a day, has the capability to handle increased water flows, Clegern said.

"It's a planning and management issue," he said. "Operators can manage this if they know heavy weather is coming."

A ConocoPhillips representative said the company is reviewing the complaint.


Advertisement

"In the near future we will be in contact with the water control bard to address this issue," said Mark Hughes, refinery spokesman.

In addition to the wastewater violations, the complaint alleges less serious permit violations reported by ConocoPhillips from January 2008 through June 2009. The water board will consider the complaint and fine at a public meeting in March.

The Rodeo refinery was fined $111,000 for 41 discharge violations from July 2003 to August 2005.