UPDATE 1-Chile's Codelco awards tender for desalination plant to Japan's Marubeni

(Adds details of consortium partners, background to desalination plan)

SANTIAGO, Nov 4 (Reuters) - Chile’s state copper miner Codelco said on Monday it had awarded a tender for a desalination plant for its Chuquicamata, Radomiro Tomic and Ministro Hales mines to a consortium led by Japan’s Marubeni Corp.

Codelco said that it expected work on the plant to kick off in the first quarter of 2020 and for the plant to be operational in 2022.

The consortium is made up of Marubeni with a 50% stake, and Chilean power transmitting firm Transelec and Argentine-Italian steel company Techint. The project has an initial capacity of 840 litres per second.

Codelco launched an international tender for the plant, with an estimated investment of around $1 billion, in 2017. It is part of a widespread overhaul of its mines to counteract a fall in ore grades. (Reporting by Fabian Cambero; Writing by Anthony Esposito; Editing by Jon Boyle and Louise Heavens)