New York Times: A coal ash spill in eastern Tennessee that experts were already calling the largest environmental disaster of its kind in the United States is more than three times as large as initially estimated, according to an updated survey by the Tennessee Valley Authority. Officials at the authority initially said that about 1.7 million cubic yards of wet coal ash had spilled when the earthen retaining wall of an ash pond at the Kingston Fossil Plant, about 40 miles west of Knoxville, gave way …