TSMC DSO is a small surface mine approximately 1,100 kilometres north-east of Montreal on the border of Newfoundland and Labrador, and Quebec, Canada. The mine is operated by majority owner Tata Steel (Tata). The NML DSO deposit is composed of Lake Superior-type iron and forms part of the western side of the Labrador Trough iron range. The area has a sub-Arctic climate with temperatures ranging from -40°C in winter to 25°C in summer, with an average temperature of -3.6°C. Transport costs are high for this operation because of the multiple rail links it uses to transport iron ore to the export port.