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.