DEP Rules Mining Damaged Dam

Washington PA Observer-Reporter
17 February 2010
By Bob Niedbala, Staff writer
niedbala@observer-reporter.com

The state Department of Environmental Protection has determined longwall mining at Consol Energy Inc.'s Bailey Mine was responsible for ground movement that damaged the dam at Duke Lake at Ryerson Station State Park.

DEP had initiated the investigation following a decision by Allegheny County Court in a lawsuit filed by the state Department of Conservation and Natural Resources against Consol seeking $58 million in damages for the dam.

A court order, issued in October 2008, directed DCNR to file a claim with DEP under the state's Bituminous Mine Subsidence and Land Conservation Act for damage sustained at the dam.

DEP said its decision came following an extensive analysis. "These findings were based on concrete information from Consol, the Department of Conservation and Natural Resources, DEP files and months of site observations," said Michael Terretti, DEP's director of mining operations.

"The department stands behind its findings and will now move into the second phase of its investigation, which is to address the appropriate remedy," Terretti said.

Consol spokesman Joe Cerenzia said the company was disappointed in DEP's decision.

"Our position is that we don't believe (the damage was) mine related and we intend to appeal the decision to the state Environmental Hearing Board," he said.

Cerenzia said mining in the area took place more than 1,000 feet from the dam, far enough away to prevent any damage. The company's mining plan also had been approved by DEP, he said.

The 62-acre lake was drained July 29, 2005, after inspections by DEP and DCNR revealed expanding cracks in the 45-year-old concrete dam. A month later, DCNR removed part of the spillway to prevent water from backing up in the lake bed during heavy rains.

DEP's interim report on the dam concludes that except for longwall mining, no other activity took place in the spring and summer of 2005 that could account for the movement of ground and damage to the dam. The report also excluded dam instability and hillside instability as potential causes.

Underground coal mines can cause ground movement and damage at greater distances than customary mine subsidence theory typically predicts, DEP said.

This was the case with the Ryerson Station dam incident where DEP found a number of other examples of subsidence such as pipeline buckling and road and stream heaving.

DEP also discovered several instances of ground movements in areas beyond the customary prediction area in its files and in examples Consol identified throughout Appalachian coal fields.

Raina Rippel, director of the Center for Coalfield Justice, said with the decision the group felt justified in its belief damage to the dam was caused by subsidence.

"All along we felt we knew this was related to longwall mining," Rippel said. "Obviously, we're not surprised (with the decision) and we feel the results are well overdue."

Rippel also said the group feels damage to the dam points out a flawed mine permitting process, in that DEP based its determination of where subsidence damage would occur on the surface on a theory which unfortunately did not hold true in this case.

DEP spokesman Neil Weaver said DEP will now begin working with DCNR and Consol on a way to remedy the situation, "whatever that may be."

Regarding DEP's issuance of the mining permit, Weaver said, the permit had been issued after it was determined to meet all the required standards.

What happened to the dam was unfortunate, he said. "No one could have expected it to happen." Weaver said it was still too early to speculate on whether this case would lead to any changes regarding mining standards.

DCNR's staff, working with the engineering firm Gannett Fleming Inc., has continue to develop plans to replace the dam, DCNR spokeswoman Chris Novak said.

"We hope to start design of a new dam in the spring," she said. "We expect that construction on a new dam would begin sometime in 2012."