Complex sentence: Greenrigg was once a thriving mining village and produced large amounts of coal, the remains of the mine can be seen in the form of a large mound of debris from the mines excavations or "Bing" as they are called locally.
Split into simpler sentences: Greenrigg was once a thriving mining village and produced large amounts of coal. The remains of the mine can be seen in the form of a large mound of debris from the mine excavations or "Bing" as they are called locally.