Water from Cienega Creek diverts into a grate at the Pantano Dam, owned by Del Lago Golf LLC on Wednesday, Aug. 28, 2013, east of Vail, Ariz. Rosemont Copper has committed to buying land parcels and water rights to compensate for its effects on the land and waterways in and around its mine site. 

Mike Christy / Arizona Daily Star

■ Rosemont will spend $25 million to buy about 4,500 acres of land and more than 1,700 acre-feet of annual water rights to compensate for impacts on streams and washes. Included: 1,122 acre feet of water rights at Cienega Creek; a 1,200-acre ranch near Sonoita Creek and its 590 acre feet of water rights; the 1,790-acre Fullerton Ranch southwest of Tucson; and Helvetia Ranch North, 940 acres north of the Santa Rita Mountains.

■ The EPA, Bureau of Land Management and Pima County say the land and water rights purchases are inadequate, in the wrong location or will be managed with inadequate money. They say Cienega Creek doesn’t carry enough water to make its mitigation plan work and Sonoita Creek is in a dierent watershed from the mine’s impacts.

■ Rosemont’s mitigation plan has been better received from the Forest Service and the Arizona Game and Fish Department. Game and Fish would manage Sonoita Creek Ranch plus $10 million in other projects. The plans’ ultimate arbiter will be the Army Corps of Engineers, which requires mitigation to approve a crucial federal Clean Water Act permit.