The leader of a New Windsor community group is skeptical an agreement between the county and a Wakefield Valley quarry operator will protect underground water supplies in the limestone-rich valley.
The agreement, signed last week, gives county approval for Virginia-based Lafarge Corp. to connect two pits at the Medford quarry. The single huge pit will descend 500 feet below ground level. Lafarge acquired the Medford quarry when it bought Redland Genstar, the former quarry owner, in June.
The quarry operator pledged to study a technique called grouting to reduce underground water flowing into the pit and possibly curb the incidence of sinkholes that pock the valley's surface. If the study's authors recommend the technique, Lafarge will negotiate with the county on whether to implement it.
Lafarge must obtain state permits before it can begin the expansion.
"It appears to me it's like sticking a finger in the dike," said Dan Strickler, president of the citizens group New Windsor Community Action Project (NEWCAP).
County attorneys and Lafarge representatives worked out the agreement over three years. The county finally agreed to a study in place of its original demand that Lafarge implement the technique to reduce the flow of water.
Mark Carroll, general manager of aggregates for Lafarge, said the quarry operator was reluctant to commit itself to implementing a technique that might not raise the water table as planned,has a wide potential cost range,and might have unexpected effects on other properties.
Lafarge has a permit to pump an average 1.3 million gallons of water a day out of the pit and is seeking state approval to pump an additional 1.2 million gallons daily.
County dealings with quarry operators "always seem to be a little less than the public's best interest," Strickler said. He said the county government did not involve NEWCAP in the negotiations that led to the agreement.
"It doesn't seem to be in the best interest of the public to only get a study," he said.
Lafarge will spend up to $50,000 to study whether blocking the flow of underground water at the quarry's north face will raise the water table north of the pit to pre-quarry levels. The study is also to determine whether grouting could reduce sinkhole formation.
Carroll said Lafarge got wide-ranging cost estimates for grouting from contractors.
"The concern was, is this going to be a couple hundred thousand dollar project or a couple million dollar project?" he said.
The difficulty with estimating cost is that when a contractor drills holes to fill with grouting material, he doesn't know the volume required until he knows the geology, Carroll said.
He said the company was also concerned about possible impact on other properties.
"If you're basically building a dam, once that water backs up, if it flows to another area, are you going to increase sinkholes there?" he said.
Carroll said if the study predicts that grouting will work to raise the water table to pre-quarry levels, as the county hopes, and will reduce the potential for sinkhole formation, the company will support it.
Pub Date: 1/06/99