OMAHA, Neb. -- Several new problems have been found at a Nebraska power plant that suffered flood damage earlier this year, federal regulators said Tuesday, so inspectors will be watching the plant north of Omaha even more closely as repairs from flooding are made.The tougher oversight for the Omaha Public Power District plant in Fort Calhoun will likely further delay its restart from early next year until sometime in the spring as it makes repairs from the summer flooding.