Anne Arundel County Executive John R. Leopold called on the state Wednesday to delay approval of putting coal ash in a landfill just across the county line in Baltimore until the federal government has decided whether the waste should be treated as hazardous. In a letter to Gov. Martin O'Malley, Leopold urged the state to stay its decision to issue a permit to Constellation Energy to dispose of ash from its Baltimore-area power plants in the Hawkins Point industrial landfill operated by Millennium Inorganic Chemical Inc.

The county executive noted that the Environmental Protection Agency announced Tuesday that it was weighing whether to regulate coal ash as a hazardous waste, and that the state has yet to adopt rules on transporting ash to keep it from becoming airborne. "There is no greater priority than protecting public health," Leopold said. At Leopold's urging, the Anne Arundel County Council banned ash from the county in 2007 after officials discovered Gambrills residents' wells had been contaminated by power-plant waste dumped at a nearby gravel pit.

The ban remains in effect. EPA proposed treating ash as either hazardous or as a less toxic form of industrial waste. The agency said it would take comments for 90 days, but did not commit to when it would decide. The Maryland Department of the Environment made a tentative determination earlier this year to permit Constellation's ash disposal on a portion of the 65-acre landfill. But environmental activists and residents spoke against it in March. MDE spokesman Jay Apperson said the agency is still reviewing comments and has no timeline for deciding on the permit. Constellation now provides about 60 percent of the ash from its Brandon Shores, C.P. Crane and H.A. Wagner power plants to be used in making concrete and other building materials.

The rest is trucked to a landfill in Virginia. Constellation spokesman Kevin Thornton has said if the company is allowed to bury ash at Hawkins Point, it intends to comply with whatever state and federal rules get adopted.