Mining Publication: Analysis of Safety Aspects and Mining Practices for Effective Ground Control in Surface Mining
Fatalities caused by highwall/spoilbank failure in the surface mines, coal and non-metal, increased to an alarming rate of seven during 1999. To determine the cause of slope failure and successful mining practice, the National Institute for Occupational Health and Safety undertook a study. The study included: 1) a review of accident statistics, 2) a review of Federal and state mining laws pertaining to surface mining, 3) a literature review, and 4) mine visits. The study emphasized surface mines in the states of West Virginia, Ohio, and Pennsylvania. The review of a decades accident statistics using the Mine Safety and Health Administrations (MSHA) database showed that approximately 40% of all ground control related incidents reported to MSHA occurred in just four eastern states: Kentucky, West Virginia, Pennsylvania, and Ohio. The comprehensive literature search provided a historical perspective of highwall stability issues. Eleven mines were visited to obtain data on their mining practice or design. Commodities included coal, sandstone, and limestone. Based on the visits, five case studies were developed to represent typical mining methods and effective ground control practices used in eastern surface mines. Benching was found to be a common technique to reduce the overall highwall slope angle. Decking in the softer zones, such as shale, proved useful in controlling damage due to blasting.