the main tunnel so work could carry on at a number of headings. Compressed air equipment, blasting, steam shovels, and narrow-gauge cars were used. At high and wide, the tunnel would accommodate double tracks. The western side involved penetrating thick mud, extremely hard rock, and finally softer rock. The highest point of the Selkirks track was just inside the western portal. Three steam shovels were based on the west side and one on the east. Death and injury were not uncommon. Mirroring the advance across the pass in the 1880s, concern for the health and safety of workers was not a priority. Beating world monthly tunneling records, the pioneer headings met in December 1915, and the main bores in July 1916. The unacceptably high cost projection scrapped the electrification plan. Instead, ventilation fans were installed. East of the tunnel, the plan for double tracking to Six-Mile Creek was amended to a level single track connecting with the existing line at Stoney Creek. This reduced the pusher gradient on the east slope by , less than specified. However, it retained the substantial investment in the bridges at Mountain, Surprise and Stoney creeks. The tunnel was completed 11 months ahead of schedule, and below budget. One calculation of costs listed tunnelling $4.91M, tunnel track $0.16M, approaches $0.86M, and ventilation $0.11M, totalling $6.04M, less the salvage value of the abandoned line $1.67M. Extending the concrete lining during 1919–1925 added a further $2.60M. The $8.64M total is in line with a different calculation of $8.45M. In all, the route was shortened by . Repairs, modifications & emergencies In 1919, 30 drums of gasoline and kerosene, used by the concrete mixers engaged in the lining operation, ignited. A tunnel watchman, who rushed some distance to the nearest telephone to alert Connaught station at the eastern portal, did not survive. His warning saved the westbound transcontinental, then at the station, from proceeding into the tunnel. Nine workers escaped on a handcar from the east portal, and one watchman staggered from the west portal. To deal with crumbling rock in the roof, the concrete tunnel lining was extended from to . Prior to the 1925 completion of the project, falling rock killed or injured several workers. In 1928, a locomotive boiler explosion killed three crew members near Glacier. In 1929, two train crew died when their locomotive fell into the ravine when a girder collapsed on the