D’Appolonia, which developed the first coal refuse design manual in 1975, said the new manual would include advances made in the past 30 years in dam safety and slurry impoundment design, construction, monitoring, inspection and instrumentation.

Specific guidance to be added to the manual included engineering analysis for siting impoundments over underground mines or adjacent to them, and consideration of earthquake impacts on refuse impoundment dam safety.

D’Appolonia has assembled an expert team to compile the manual, including Richard Almes and Vincent Scovazzo, experts on impoundment design and subsidence risk associated with underground mines.

Since publication of the 1975 manual, the coal industry has made dramatic strides in the design and construction of large impoundments capable of performing in an efficient and environmentally sound manner.

In recent decades, impoundments have been developed using dams constructed of soil and rock, coal refuse and combustion waste to significant heights, at times exceeding 500ft. Some impoundments accommodate refuse generation rates of up to 4 million tons per year.

D’Appolonia anticipates the updated manual will be a critical reference tool for coal operators, engineers and regulators as the industry continues to expand to meet growing energy demands.

Manual completion is expected March 2007.