Complex sentence: In the post-war years the DAR moved to replace its steam locomotives with diesel-powered models, however the railway was relatively late among its North American counterparts in doing so (possibly owing to abundant coal being mined in Nova Scotia).
Split into simpler sentences: In the post-war years the DAR moved to replace its steam locomotives with diesel-powered models. However the railway was relatively late among its North American counterparts in doing so (possibly owing to abundant coal being mined in Nova Scotia).