We told you Friday that an oil spill occurred at the Lake Sam Rayburn Dam and oil flowed into the Angelina River. According to power plant officials the dam experienced a main power transformer failure at some point last Monday morning and it was noticed by workers at the facility that oil sheen was appearing on the river around mid morning. Less than 100 gallons of non-hazardous insulating oil escaped into the Angelina River, and no oil made it into Lake Sam Rayburn. Officials say the spill is not expected to have any environmental impact on the waterway. The dam is expected to resume its generating as early as today.