1991: First exploration activities and discovery of the Chailhuagón and Perol deposits by CEDIMIN (Compañía de Exploraciones, Desarrollo e Inversiones Mineras).
1994-2000: Research by CEDIMIN in both deposits.
2001: Acquisition of CEDIMIN by CMB. Conga Project joins the operations of the Yanacocha complex under the administration of MYSRL.
2001-2004: Planning of studies and management of permits and land acquisitions for the complete exploration campaign is developed by MYSRL.
2004: Start of exploration activities of the Conga Project in Chailhuagón and Perol deposits and decision to further develop the Conga Project.
2005-2007: Environmental baseline studies carried out by MYSRL.
2008: Update of environmental baseline studies and development of project engineering. Approval of Semi-detailed Environmental Impact Study (sdEIS) for Conga Exploration Project by the Ministry of Energy and Mines. (RD N°243-2008-MEM/AAM)
2009: Approval of First Modification of sdEIS by the Ministry of Energy and Mines. (RD N°081-2009-MEM/AAM). Start of drilling activities.
27 October 2010: Approval of EIA by the Ministry of Energy and Mines through Resolución Directoral N° 351-2010-MEM/AAM, with a favourable opinion of the National Water Authority and the Ministry of Agriculture.
3 November 2011: The ministers of Energy and Mines, Agriculture and Environment visit the threatened mountain lakes. Ricardo Giesecke, minister of Environment, declares that his ministry will review the EIA of the Conga Project.
9-10 November 2011: Opponents of the Conga Project block the roads between Cajamarca and Bambamarca and the access roads to Cajamarca, while students occupied the National University of Cajamarca.
11 November 2011: Opponents of the Conga Project announce a regional strike for the 24th of November.
23 November 2011: In an attempt to avoid the general strike, Premier Salomon Lerner invites the authorities of Cajamarca to Lima to discuss the Conga Project. The majors of the affected communities, however, stay away. In Cajamarca, Interior minister Oscar Valdés tries in vain to convince the authorities to blow off the strike and come to Lima.
24 November 2011: Thousands of villagers gather in Cajamarca on the first day of the indefinite regional strike. Regional president Gregorio Santos, local majors and 1.500 villagers meet at laguna Perol. They ask the resigning of the Minister of Energy and Mining Carlos Herrera and the definitive cancelation of the Conga project. In the evening, Minister of Environment Ricardo Giesecke hands over an 11 page report with the comments of his ministry on the EIA of the Conga Project to prime minister Salomón Lerner.
29 November 2011: After 6 days of regional strike, on request of the government Yanacocha announces the temporal suspension of the Conga operations “in order to re-establish rest and social peace”. Protesters repeat their demand for an official cancellation of the project.
4 December 2011: Prime Minister Salomón Lerner travels to Cajamarca to dialogue with regional authorities and civil society leaders. After a day of fruitless talks, president Humala announces State of Emergency in four provinces starting at midnight.
5 December 2011: The Regional Council of Cajamarca unanimously approves a regional ordnance declaring the protection of headwater areas of regional interest and declaring the inviability of the Conga Project. After its publication on 29th December, the central government asks the Constitutional Court to declare it unconstitutional.
10 December 2011: Prime Minister Salomón Lerner and most of the other ministers resign. Disputes over the handling of the Conga-conflict and other issues are at the root of the decision. Lerner is replaced by Oscar Valdés a former military.
16 December 2011: After regional authorities have agreed to meet Oscar Valdés on 19 December in Cajamarca, the State of Emergency is lifted.
19 December 2011: Prime Minister Oscar Valdés travels to Cajamarca in order to dialogue. However, regional president Gregorio Santos refuses to sign the act, accusing Valdés of not listening and imposing his will.
27 December 2011: Working meeting between representatives of the central government and representatives of Cajamarca about the international peer review of the EIA of the Conga project. The regional government and local governments of the direct influence sphere of Conga are not present.
2-3 January 2012: Another two days of peaceful protest take place in Cajamarca. A national march for water is announced for the end of the month.