The South African mining firm Gold Fields bought this mine in Hualgayoc (district), Cajamarca (region) in 2003. The state approved the company's environmental impact assessment in December 2005, and the company began constructing its Cerro Corona mine, directly on the former mine, the following months. The Peruvian ombudsperson first reports about local concerns regarding water pollution and scarcity in 2006. The area is known to have more than 900 registered environmental hazards, including dozens of ponds polluted with heavy metals. Company officials claim this is related to centuries of mining in the area, but several large-scale, cyanide and mercury-intensive mining operations in recent decades are mainly responsible. There have been at least three strikes and demonstrations aimed at the company since 2006, but no property damage has been registered, nor has any police violence against demonstrators. On one occasion, a company representative was detained by authorities from the local Rondas Campesinas, but these groups are legally empowered to detain suspects temporarily, so whether this is framed as a kidnapping or not is a matter of debate.