While regulators and industry officials say these facilities are safe, coalfield residents have lived in fear of coal-slurry dams since Buffalo Creek, a disaster that prompted major reforms and led to passage of the 1977 federal strip-mining law.
Measures of how well slurry used for embankment construction compacts are one of the factors that goes into calculating whether such dams are stable and safe. Mine operators or their consultants estimate the expected compaction of the construction material when they apply for permits from DEP.
West Virginia law does not require mine operators to perform periodic compaction testing, but DEP typically includes a mandate for such tests -- about once a week -- as a condition of permit approval.
But over the years, federal and state agencies have generally not performed any spot-checks to confirm that company compaction tests are properly done or ensure companies are accurately reporting the results.
"Much like the Clean Water Act program, the dam program has been self-verification and self-reporting by industry," said Tom Clarke, director of the DEP Division of Mining and Reclamation.
OSM engineers, though, "became concerned that embankment construction quality control may be inconsistent," according to the report summary.
Federal agency engineers, "observed cases of material being placed under wet conditions, excessive lift thicknesses, and consultants recording passing test results when visual observations (pumping and rutting) indicate the material may not be adequately compacted."
Among other things, OSM officials questioned why the mining industry most frequently uses bulldozers to compact dam construction material, when dozers are not designed for that purpose and other equipment could be more effective.
"I'm proud we've gone this far," said Roger Calhoun, director of OSM's Charleston field office. "We're on the cutting edge with these tests. The citizens asked for this. They said, "don't trust the companies, check them.'"
But after OSM completed its testing and the results were in, DEP officials complained about the federal agency's methods.
Jim Pierce, a DEP dam safety engineer, said Thursday that OSM investigators tested an upper layer of coal refuse that had not had a chance to compact, and wrongly averaged results from multiple tests at the same impoundment.
DEP hired its own consultant to perform more tests. Those tests are done, and the two agencies are reviewing the results and discussing the matter further with the U.S. Mine Safety and Health Administration, which also regulates coal-slurry impoundments.
There is no timeline for completing the work, said DEP spokeswoman Kathy Cosco.
Reach Ken Ward Jr. at kw...@wvgazette.com or 304-348-1702.