Undocumented immigrants in El Paso rang up more than $30 million in unpaid medical bills in 2000 -- the second-highest amount for a border county, after San Diego -- according to a study being released today. The U.S.-Mexico Border Counties Coalition, a group of elected officials from 24 border counties in four states, commissioned the study to put pressure on Congress to reimburse border hospitals for providing emergency medical services to undocumented immigrants. "We've said all along that the federal government should pay for this because it's a federal mandate for hospitals to treat everyone regardless of nationality," said Pete...