Drivers across the U.S. enjoying the lowest pump prices for this time of year since 2010 will probably see further declines as refineries benefiting from the shale boom produce record amounts of fuel. The average is $3.433 a gallon, down 6 percent since Memorial Day on May 26, AAA data show. That’s the largest decline from the start of the summer driving season since 2008. U.S. refineries operated at the highest-ever seasonal rates every week since July 4. Processors are using domestic crude that costs less than foreign imports as horizontal drilling and hydraulic fracturing in shale formations increased output to the most since 1986. Gasoline will drop another 10 to 20 cents a gallon by the end of October as retailers switch to cheaper winter-blend fuel, said Michael Green , a Washington-based spokesman for AAA, the largest U.S. motoring group. “Refineries this summer were running at record-high levels […]