Conclusions and Recommendations - Coal Waste Impoundments: Risks, Responses, and Alternatives - page 149

8
Conclusions and Recommendations
The charge to the committee includes three major components. First, the
committee was asked to examine engineering practices and standards currently
being applied to coal waste impoundments and to consider options for
evaluating, confirming, improving, and monitoring the various barriers that
retain coal waste material within impoundments. Second, the committee was
charged with evaluating the accuracy of mine maps and exploring ways to
improve surveying and mapping for underground coal mines with the goal of
delineating more accurately how underground mines relate to current or planned
slurry impoundments. The third committee task was to evaluate alternative
technologies that could reduce the amount of coal waste generated or allow
productive use of the waste. This chapter summarizes the committee's
conclusions, outlines the rationale for those conclusions, and reviews the
recommendations that follow from them.
ENGINEERING STANDARDS, BARRIER STABILITY, AND
MONITORING
The regulatory structure that governs the design process is outlined in
Chapter 2 , and a detailed review of the current engineering practices used in the
design of coal waste impoundments is given in Chapter 3 . A substantial
regulatory structure exists, and a detailed regulatory review process that covers
many key aspects of the design, construction, and operation of coal waste
impoundments is in place. The review of the impoundment basin has been less
detailed and rigorous, and the series of incidents that involved releases of coal
slurry material from impoundment basins (see Sidebars 1.3 to 1.11 ) indicates
that more investigation of the potential for loss of integrity of an impoundment
in the basin area is appropriate. Special attention should be given to the
potential for breakthrough of coal slurry into underground coal mines. The
authority for review of basin characterization and design