MADISON, Wis. (AP) -- The state Department of Natural Resources says it will reconsider a key permit for a large dairy farm proposed in Adams County because of the effect on local water supplies.

The DNR had made a preliminary determination that groundwater used by the 4,200-cow farm wouldn't harm local supplies. But, a University of Wisconsin-Stevens Point hydrogeologist has concluded Richfield Dairy, being developed by Milk Source of Kaukauna, will harm local bodies of water and draw down the aquifer.

Milk Source spokesman Bill Harke says two other studies have been supplied to the DNR which show the farm won't have an effect on area water supplies.

Milk Source also owns the state's largest dairy farm, Rosendale Dairy, in Fond du Lac County, and operates two other farms.