The latest battle for Tía María is about to be engaged. The large copper project in the province of Islay in the department of Arequipa has been the focus of strong social discord since 2011: two major waves of social protest in 2011 and again in 2015 resulted in seven deaths and many wounded. The cases of protesters charged with disturbing the peace are still in the courts.

The project is owned by Southern Peru Copper Corporation, a subsidiary of Grupo México. One of five top priority projects in the mining sector, a head of steam is gathering behind it to get the official go-ahead. But fierce opposition is building up too.

The issue from the start has been the conviction of agriculturalists that the project will gravely affect their supply of water. In response to previous bouts of protest, the company modified its EIA to introduce a desalination plant as an alternative source, but that has given little reassurance. The company claims it has worked hard to build social support, but a survey it produced at the end of last year was singularly non-transparent in its methodology and resolved nothing.

The pressure is now acute. If the company does not receive its construction licence from the government by 1 August, the EIA will be out of date (it was approved five years ago) and will need to be re-worked and re-presented. This could mean a two-year delay.

But the organised forces on the ground are bitterly opposed to the granting of the construction licence. They have called in the governor of Arequipa, Elmer Cáceres, who has taken the line that it is not sufficient to grant the construction licence when there is patently no ‘social licence’. Social license is a concept without legal force but with considerable ethical and political weight.

He has called for a dialogue table (mesa de diálogo) to work towards consensus, pressing that such a forum would consider the whole sweep of development needed by the region (in particular, a large dam for Islay), since this is the area of impact of the mine. Without a social licence, he says, the project should not go ahead.

The government has backed the idea of a dialogue table with a broad mandate. No date has yet been announced, though the first steps have been taken to organise it. The key producer organisation, the Junta de Usuarios del Valle de Tambo, says it does not want a dialogue table; it wants the president to come and witness for himself the strength of opposition to the project. The Junta is planning to announce an indefinite strike starting 30 June.

While the company still insists that the project enjoys public support, La República on 28 June published the results of a survey it had commissioned. This is based on a survey of 436 citizens in 13 districts of the province of Arequipa and demonstrates striking results: of those interviewed 62% were opposed to the project, 34% in favour. The disapproval rate rose to 71% in the social categories D and E (those on lower incomes).