Work has been delayed due to concern about environmental impact and lack of consultation with affected indigenous people.

[1] The project would be undertaken by a consortium of Eletrobras, Eletronorte, Construções e Comércio Camargo Côrrea, EDF Consultoria em Projetos de Geração de Energia, Endesa Brasil, EPP Energia Elétrica, Promoção e Participações, Intertechne Consultores Associados and Neoenergia Investimentos.

[7] Eletronorte, Camargo Corrêa and CNEC Engenharia undertook hydraulic inventory studies of the Tapajós and Jamanxim Rivers, which were approved by the National Electric Energy Agency (Aneel) in 2009.

That year Aneel approved the start feasibility studies of the Cachoeira dos Patos, to be delivered on 31 July 2011.

They had not undertaken an Integrated Environmental Assessment and had not consulted with the affected indigenous peoples, both legal requirements.