MORGANTOWN, W.Va. (AP) -- A draft report kept under wraps since 2011 shows federal engineers are concerned about construction techniques, quality-control procedures and possible compaction problems at seven West Virginia coal slurry dams subjected to surprise inspections.
The citizens' group Sludge Safety Project obtained a one-page summary of the report that the federal Office of Surface Mining and Reclamation has refused to release. About a dozen people gathered outside agency offices Thursday in Charleston to share it.
Some coalfields residents have long worried that massive impoundments were improperly built and could fail, unleashing a destructive and potentially fatal flood of sludge and black water.
"This is the cheapest, easiest, sorriest way to get rid of this material," said retired miner-turned-activist Joe Stanley. "An average mine that, say, runs a 35-year lifetime here in West Virginia will accumulate 200 million tons of this refuse in 30 years. What are they doing with it? They're putting it up in a hollow. These things could liquefy."
OSM, however, found no indication any impoundment is in imminent danger of failure, spokesman Chris Holmes said.
Holmes said the report is a draft that's far from completion, and more testing and data analysis are needed.
"The bottom line is this: Good science and engineering takes time and effort to complete," he said, "and that is what OSM is committed to doing."
This is the first time a federal agency has studied whether the material inside coal slurry ponds is properly drying and compacting, even though some are 30-40 years old.
The West Virginia Department of Environmental Protection said it, too, had concerns about the report's methodology and is working with OSM on "an accurate assessment." Spokeswoman Kathy Cosco also said DEP is working with federal agencies to ensure impoundments are properly built.
Rob Goodwin, who monitors dams for environmental groups, said the review is long overdue. The OSM summary shows state and federal regulators must stop accepting self-reported data from coal companies, he said, and conduct their own independent examinations.
Regulators should also impose a moratorium on the expansion of existing impoundments, Goodwin said, especially the Brushy Fork dam built by the former Massey Energy Co. near Whitesville.
Federal regulators recently approved plans by the current owner, Virginia-based Alpha Natural Resources, to expand what is already one of the nation's biggest coal slurry impoundments to a height taller than the Hoover Dam. The plan would increase the volume of waste to 8.5 billion gallons.
"There's no emergency evacuation plan," worries Freda Williams, who's lived in Whitesville for 50 years. "If there were a breakthrough, there's nowhere for the people to go. ... Everyone would be on their own."
Public records show a failure at Brushy Fork could create a 100-foot wave that would hit Sherman High School in 17 minutes.
Goodwin said citizens have long questioned stability of such dams, "yet state and federal agencies have insisted they're safe and meet legal requirements."
The problem, he said, is those determinations rely on the companies to provide "honest and accurate data."
Neighbors worry about Brushy Fork because the engineer long responsible for the impoundment was also involved in illegal ventilation plans at Massey's Upper Big Branch mine, where an April 2010 explosion killed 29 men.
The Mine Safety and Health Administration later discovered Massey maintained two sets of safety records, one sanitized to mislead inspectors.
The engineering firm Massey used on Brushy Fork was also linked to the 2000 failure of a Massey impoundment in Martin County, Ky. Slurry burst through the bottom of a 68-acre holding pond, sending black goo through an underground mine and into 100 miles of waterways. It polluted the water supply of more than a dozen communities.
Slurry is the soupy waste created when coal is washed to help it burn more cleanly.
In central Appalachia, companies use impoundments to dispose of "coarse refuse," or larger pieces of rock separated from coal, and "fine refuse," or clay, silt and sand-size particles. Fine refuse is pumped into the reservoir behind the coarse refuse. Over time, the "fines" are supposed to settle to the bottom, compressing and solidifying.
But the report summary says inspections at the West Virginia impoundments raise questions about whether theory is reality: It says coarse refuse is "primarily low-plasticity silt with rock fragments and some clay," materials that are typically harder to dry out and compress.
That material often arrives at the disposal site wet and in cold weather that makes it impossible to control moisture content, the report says. Bulldozers are then used to compact the material, even though they're designed to work with soil and loose earth.
"Results of the testing tend to indicate that the coarse refuse is not consistently being compacted in accordance with approved specifications," the summary says.
All seven impoundments failed field density tests, the report said. Of 73 total tests, only 16 produced passing results.
In all, federal records show there are nearly 600 coal slurry impoundments in 21 states.
West Virginia has the most with 114, but it hasn't had a major failure since 1972, when the earthen dam at Buffalo Creek collapsed after heavy rain.
The flood killed 125 people, injured 1,100 and left 4,000 homeless.
Associated Press writer John Raby contributed from Charleston.