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By Jonathan Kaminsky
NEW ORLEANS, Jan 20 (Reuters) - BP Plc will try towhittle away at $13.7 billion in potential fines under the CleanWater Act as the penalty phase starts on Tuesday in its trialover the 2010 Gulf of Mexico oil spill.
Several billion dollars in potential fines were avoided onThursday when U.S. District Court Judge Carl Barbier put thesize of the spill at 3.19 million barrels. That was well belowthe government's estimate of 4.09 million barrels, which couldhave led to $17.6 billion in fines for the worst offshoredisaster in U.S. history.
The Clean Water Act penalties would come on top of more than$42 billion the oil major has set aside for cleanup,compensation and fines. About 810,000 barrels were collectedduring cleanup.
Clean Water Act rules say when assigning penalties the courtmust take into account BP's ability to pay, history of pastviolations, and steps it took to clean up the spill.
The U.S. government named as the defendant in the case BP'sexploration and production unit, known as BPXP, which couldconceivably limit the size of the fine.
"We believe that ... BPXP should be subject to a Clean WaterAct penalty at the lower end of the statutory range," AndrewLangan, a lawyer for BP, said in a statement.
Environmental groups say it could take decades for the Gulfecosystem to recover. They disagree with BP's assertions thatthe Gulf has recovered better than expected.
"The court has the opportunity and responsibility ... tohold BP fully accountable for the damage done to the Gulf and toassign the maximum penalty," the National Wildlife Federationsaid in a joint statement with other groups.
The first two phases of the trial, over the degree ofnegligence and the spill's size, have concluded.
Under a "gross negligence" ruling Barbier issued inSeptember, BP could be fined a statutory limit of $4,300 foreach barrel spilled, though he has authority to set lowerpenalties.
BP has also filed motions saying the maximum fine per barrelis in fact just $3,000 because Congress never passed laws toadjust it for inflation.
A simple "negligence" ruling, which BP sought, caps themaximum fine at $1,100 per barrel.
After the Clean Water Act fines are set, BP may face otherbills from a Natural Resources Damage Assessment - which couldrequire BP to fund environmental restoration work - and otherclaims. (Writing by Terry Wade; Editing by Lisa Shumaker)
