A Case Study of Abandoned Mine Subsidence at Dominion, Nova Scotia, Canada, 2002-2003

Dave Forrester PhD, PEng

Mining subsidence over shallow abandoned coal mine workings is unfortunately not an uncommon experience in the coalfields of North America, and there is a significant knowledge and literature base addressing the phenomenon and related issues. From time to time, however, a case history arises which is outside the more routine occurrence.

This presentation looks at one such case and presents an overview of a subsidence event above abandoned coal workings, which badly damaged a two-storey High School building. The subsidence at the Cape Breton & Victoria Regional School Board (CBVRSB)’s MacDonald High School in Dominion, N.S., Canada on 30 October 2002 led to a detailed investigation. It was concluded that the ground movement and associated building damage had been caused by mining subsidence in underlying old underground coal mine workings of the 1890s, at depths of only 150 ft (45 m) at the School. The event was not isolated and a similar but smaller event happened nearby a few months later. The presentation will outline the events and summarise the subsequent investigations and findings. The 18-year old high school building was eventually demolished.

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