S&ME, Inc. has been retained by the North Carolina Department of Transportation (NCDOT) to provide technical assistance and programmatic permitting services for land application of wastewater generated by hydro-demolition and diamond grinding of concrete which is being used by the NCDOT during bridge concrete maintenance and concrete pavement roadway projects. This on-call contract was awarded by the NCDOT Geotechnical Engineering Unit Geoenvironmental Section in 2009, and the contract is on‑going.
S&ME, Inc.’s Licensed Soil Scientists and Agronomists are providing technical assistance to the NCDOT in managing the wastewater from hydro-demolition and diamond grinding of concrete, which includes two unique by-products – hydro-demolition runoff water and diamond grinding slurry. Hydro-demolition runoff water is generated during the replacement process of bridge decks when the old concrete is removed through the use of high pressure water. Diamond grinding slurry is generated through the diamond grinding of concrete pavement which generates a slurry material consisting of water and pulverized concrete.
Projects to date have been located in the following counties: Wilkes, Iredell, and Wake. The new Western Wake Expressway (Wake County) is one of the first NCDOT projects where the diamond grinding process was used on the concrete for the entire length of the project. The hydro-demolition runoff water and the diamond grinding slurry both have a high pH and are beneficial to soils for pH adjustment. S&ME is assisting the NCDOT with the permitting and the land application of these products on highway right-of-ways and medians. Permits are obtained from the Division of Water Quality (DWQ) Land Application Unit (LAU). This was a new permitting process for both NCDOT and the DWQ-LAU.