Mining commenced today on the 23rd Avenue Storm Sewer Design Build Contract with the City of Edmonton. Dibco-CRS, A Joint Venture was awarded this contract which consists of a 215m long x 3.0m I.D. segmentally lined tunnel, between shafts 6A and 6C, using a RME 137SE Earth Pressure Balance (EPB) Tunnel Boring Machine. Other works to be performed on this project consist of the completion of Shaft 6A and enlarging the Retrieval Shaft (6C) from 4.5m to 8.0m ID. The 3m ID segments for the project were cast locally at Lafarge Canada Inc. Project challenges include successfully mining in very soft water bearing soils while maintaining surface settlements to a minimum, and negotiating a 210m radius curve.
