The Tennessee Valley Authority, Knoxville, Tenn., has awarded San Francisco-based URS Corp. a five-year, $20- million contract to provide engineering and construction management services for conversion of wet coal-ash storage facilities at five coal plants to dry storage systems. The upgrade follows the 2008 storage pond failure at a TVA plant in Kingston, Tenn.

Under the contract, URS will handle conversion of storage systems at the Colbert, Widows Creek, Gallatin, Bull Run and John Sevier power plants, located elsewhere in Tennessee and in Alabama. TVA agreed to move to dry coal-ash storage systems after the Kingston coal-ash impoundment collapsed, contaminating thousands of nearby acres and the Emory River.

The cleanup at that facility is still ongoing. As of April 13, about 3.1 million cu yds of the 5.4 million cu yds that spilled have been dredged and removed from critical land areas. Jacobs Engineering, Pasadena, Calif., is managing cleanup, with Sevenson Corp., Niagara Falls, N.Y., performing dredging.

The critical coal-ash removal is expected to be complete by May 15, when federal and state officials are set to approve a plan for removal of the remaining non-critical ash. The plan will include details of how the coal-ash conversion will occur at Kingston, officials say.

TVA says that converting from wet to dry storage at all six of its coal plants could cost up to $2 billion. Utility spokeswoman Barbara Martocci says it will be awarding additional contracts associated with the conversions. 