The sewage spill on the Tijuana River in Mexico the fouled South County beaches may have been significantly larger than first estimated, although it’s unclear how regulators arrived at the new figure. Standing next to the river valley for a news conference Monday, Rep. Scott Peters said the U.S. Environmental Protection Agency now suspects that discharges may have totaled 230 million gallons, up from the initial figure of 143 million gallons. The original volume already ranked as one of the biggest spills in the region’s history.