Implementing Atmospheric Risk Assessment in Mine Reclamation

摘要

Being unable to identify the presence of a hazard is one of the main causes of a confined space accident. The complexity of a mine with many site-specific and heuristic chemical, physical, biological, and hydrogeological characteristics makes it difficult to apply a consistent set of general safety regulations and methods to assess confined space risks - particularly in the area of mine waste management. Development of a risk assessment manual to identify the potential of a confined space hazard at a waste dump is suggested as a way to address this problem. It is well-known that air inside a waste dump is generally oxygen-deficient. Furthermore, "best" practices for waste dump reclamation attempt to seal the surface to minimize water and air infiltration. Good drainage ditches are designed to divert water flows and collect effluent that passes through the dump. Effluent sampling is done to monitor quantity and quality. What is not so obvious is that combining these "best" practices may create a confined space hazard not only within a man-made structure such as a sampling shed, but also within a surface depression or digging, pipe, or drillhole. This paper will describe a confined space event that resulted in a tragedy at the Sullivan Mine in Kimberley, B.C. in May 2006. The paper describes how a method using fuzzy logic can be used to help identify these risks and prevent future accidents.