The need for more sophisticated pollution controls at power plants as led to an increased demand for limestone. And a quarry in Meade County has installed new equipment to meet that demand.Power plants have to reduce sulfur dioxide emissions, and one popular way of doing that is running it through layers of crushed limestone mixed with water. The sulfur dioxide bubbles through the high-calcium limestone, and doesn’t go out the smokestack.Hilltop Basic is a Cincinnati-based company that’s owned the quarry in Battletown since 2004. The company has mainly produced limestone for use in construction. But as more power plants have installed pollution controls to comply with the Clean Air Act, they’ve had to ramp up production.“The whole basis of the quarry here is premised on the fact that there’s a need for limestone for flue gas desulfurization,” said John Morgan, Hilltop’s Vice President of Mining Operations.Before the new equipment was finished, the quarry was in operation 20 hours a day, seven days a week to meet the increased demand for limestone. Now, it can operate 8 hours a day, five days a week to produce the same amount.