Engineer: The Metropolitan Sewer District of Greater Cincinnati
Start Date: January 2022
Description: Installation of 325 linear feet of 24-inch steel casing and 405 linear feet of 36-inch in 2 separate bores for 8-inch sanitary sewer in order to eliminate an existing pump station. A combination of pilot tube auger boring and guided auger boring methods were utilized to facilitate installation. The 24-inch casing was installed using pilot tube auger boring. NST tried to install the pilot tubes on the 405 linear foot bore, but this was not successful due to sudden outcropping of rock or potential obstruction. NST retracted pilot tubes and increased casing size to 36-inch in order to accommodate guided auger boring methods and allow access to the bore face in the event obstructions were encountered. Soils consisted of clay with intermittent layers of weathered shale and boulders.