The county commissioners signed an agreement yesterday that requires the owner of a Wakefield Valley quarry to study ways to protect underground water supplies before going ahead with a major expansion.
The agreement requires Lafarge Corp., owner of Medford quarry operator Redland Genstar, to finance a study of a technique that could reduce the volume of water pumped out of the pits. Hydrogeologists say the technique will help preserve water supplies north of the quarry and may reduce the incidence of sinkholes in the area.
"The company is anxious to move forward," said attorney Charles "Mike" Preston, representing Lafarge.
Lafarge received approval in 1995 from the Carroll County Planning and Zoning Commission for an expansion that would link two pits in a single 500-foot-deep pit.
Negotiators for Lafarge and the county government spent three years working out the agreement signed yesterday.
County officials had sought to have the quarry operator post a bond guaranteeing that it would implement the water supply protection technique, called grouting.
The agreement to study the technique's feasibility for the Medford quarry came after Lafarge officials argued that grouting might not work in Wakefield Valley's underlying rock or might be prohibitively expensive.
The Maryland Department of the Environment permits Lafarge to pump an average of 1.3 million gallons of water daily from its Medford quarry pits. The corporation has applied to nearly double the total, to an average 2.5 million gallons a day, for the planned expansion.
The water that flows through the limestone underlying Wakefield Valley is "just like a well," said county hydrogeologist Tom Devilbiss. "You pump it, you draw the water down. Only they can't stop pumping. They have to keep it [the pit] dry."
The idea behind grouting is to seal an underground area at the planned perimeter of the quarry, preventing the water from reaching the pit.
"That will let the water come back up on one side and eliminate water inflow into their pit on the other side," Devilbiss said.
Grouting is proposed for the north side of the quarry, an area of the valley that includes several industrial users, the Westminster sewage-treatment plant and some residential wells.
Pub Date: 12/29/98