The South Wellington No. 5 Mine of Canadian Collieries (Dunsmuir) Ltd., opened in 1917 and was worked until 1935. The coal seam is part of the Douglas Seam in the Early Campanian Newcastle Member which occurs within the Upper Cretaceous Pender Formation, Nanaimo Group. It is high volatile bituminous in rank and varies in thickness from 0.1 to 9.1 metres. The coal seam strikes northwest and dips to the northeast. The coal is overlain by sandy shale and rock partings within the seam are common. The seam is underlain by undulating shales. The weak sandy shale floor showed more frequent irregularities than the roof which was described as either a sandy shale or a coarse grit. In 1928, the Main slope was abandoned. Steps were taken to reopen the old Alexandria Mine (092GSW025) which adjoins the Main slope of the No. 5 mine. The dewatering of the Alexandria mine that commenced in 1929 was successfully completed near the end of 1930 and coal was produced from the connected No. 5 and Alexandria mines from 1932 to 1935 at an average daily output of about 694 tonnes. Both mines were abandoned in late 1935.