RE:RE:RE:RE:Tunnel under the 401 ? As Premier Ford said, Aecon is recognized for its tunneling and underground construction expertise, namely with comparable large-scale projects (Eglinton Crosstown, John Hart Generating Station Replacement, ..) both in soft ground tunneling using techniques such as Earth Pressure Balance (EPB) and Slurry Tunnel Boring Machines (TBMs) for urban infrastructure projects and hard rock tunneling, drilling and blasting lor TBM tunneling through solid rock formations. Saves a fortune in resettlement, land negotiation, expropriation, environmental issues, ..and time.