Specifications include, but are not limited to: The improvement includes hydro-demolition and replacement of a portion of the concrete lid for anaerobic digester No. 3, pre-cast concrete panel and joint repairs and cleaning to the exterior of anaerobic digesters No. 1-6, concrete crack repairs to the lid of anaerobic digesters No. 2-6, installation of new water level sensors and associated work for anaerobic digesters No. 2-6, and all other associated work and incidental items; all in accordance with the contract documents, including Plan File No. 643-115/127, located at the Wastewater Reclamation Facility, 3000 Vandalia Road, Des Moines, Iowa; 1. Anaerobic Digester No. 3 Structural Lid Repairs: a. Hydro-demolition and replacement of edge of concrete lid and associated accessories such as water stops, joint material, and joint sealant.; b. Removal and re-installation of existing railing around perimeter of lid.; c. Watertightness testing as described in Specification Section 01 45 25.; 2. Digester Complex Exterior Repairs: a. Cleaning of exterior precast concrete of all six digesters.; b. Repair of precast concrete connection damage on all six digesters.; c. Replacement of precast concrete joint sealant on all six digesters.; d. Concrete cover crack injection on Anaerobic Digesters Nos. 2 through 6.; 3. Digester Complex Level Instrumentation Installation: a. Installation of new level instrumentation at the central dome of Anerobic Digesters Nos. 2 through 6.; b. Connection of these instruments to electrical and controls panels in adjacent digester control buildings.