The Baltimore Red Line rapid transit system (Red Line) will consist of a new 14.1 mile, east-west Light Rail transit line that will interconnect with Baltimore’s existing light rail, metro, and MARC transit systems. The project includes both surface and tunnel segments with 19 stations. There will be two tunnel sections. The first tunnel section will run along the north side of the Inner Harbor approximately 3 miles (comprising 5 stations). The second tunnel segment will run 1 mile along the western side of the city and underneath Cooks Lane.
Yu & Associates, Inc. (YU) has provided geotechnical services for both the Preliminary Engineering (PE) and the Final Engineering (FE) Design Phases of the project. During the PE and FE Phases, YU oversaw and supervised subsurface investigations using hollow stem auger soil drilling, NQ3 and NQ2 rock coring, hydrostatic Packer testing, oversight of acoustic televiewer logging of boreholes, and the installation and development of observation wells. Subsurface soils and rock included miscellaneous fill, marine clay, sand, glacial till, cretaceous material, and bedrock of schist, marble, gneiss, granite and amphibolite.
During the FE Phase, YU performed geotechnical engineering inspection and oversight of Sonic Drilling operations for sampling of cobbles and cretaceous materials ending at bedrock refusal.
YU also provided geotechnical engineering inspection for an array of 9 sets of Cretaceous (CP) and Transitional (TP) boreholes/monitoring wells to confirm the boundaries of the cretaceous layer to accommodate the monitoring and Pump Test wells.