Rio Tinto joint venture Robe River Iron Associates’ has asked Western Australia’s Environmental Protection Authority for permission to develop the Mesa H deposit in order to sustain its iron ore production operations within the Robe Valley in the western Pilbara region.

Under the proposal Rio Tinto intends to disturb an additional 2200 hectares to develop, above and below the water table, a number of open cut iron ore pits and associated water management infrastructure adjacent to the existing Mesa J mine, which is approved and operates under a Ministerial Statement.

The ore will be extracted with conventional drill and blast and load and haul open cut mining methods as per the adjacent Mesa J operations.

Under the EPA’s Statement of Environmental Principles there are six key environmental factors relevant to the proposal: flora and vegetation; terrestrial fauna; subterranean fauna; hydrological processes; inland waters environmental quality; and social surroundings.

Factors that could affect flora and vegetation values include the clearing of vegetation in mining and infrastructure development areas including vegetation communities of local significance and priority flora species; vehicle and earth movements spreading existing weeds and/or introducing new weeds; and transportation increasing dust emissions and causing localised stress of adjacent vegetation.

However, according to Rio Tinto, no environmentally sensitive areas or declared rare flora will be affected by the proposal as none have been recorded in the development envelope, and considers the proposal is likely to meet the EPA objective for flora and vegetation.

In regards to terrestrial and subterranean fauna, Rio Tinto states in the proposal that clearing vegetation will directly disturb fauna habitat and may result in the loss of individuals.

Within the development envelope seven broad fauna habitat types are recorded, with three habitats considered important sites of refuge for conservation listed fauna.

There were 169 vertebrate fauna species recorded within the envelope, including two amphibian, 55 reptile, 85 bird and 27 mammal species; and eight conservation listed fauna species.

These are the Pilbara Olive Python; the Northern Quoll; the Pilbara Leaf-nosed Bat; the Ghost Bat; the Rainbow Bee-eater; the Eastern Great Egret; the Lined Soil-crevice Skink; and the Western Pebble-mound Mouse.

Four of these – the Pilbara Olive Python, Northern Quoll. Ghost Bat and Pilbara Leaf-nosed Bat – are classified under the Environment Protection and Biodiversity Act 1999 as national environmentally significant species.

Additionally, the Parks and Wildlife department recommended additional Ghost Bat work was needed, given the creature’s recent inclusion on the Environment Protection Biodiversity Conservation list of nationally threatened species, and requested more information on roosts of the Pilbara Leaf-nose Bat.

Listed factors that could affect terrestrial and subterranean fauna values and possibly result in the loss of individuals include vibrations from vehicles; noise and dust from mining and ore transportation; vehicle movements; groundwater extraction;  surplus water discharge; and surface water diversions. 

Despite all of those, Rio Tinto considers its proposal will still meet the EPA objectives for fauna.

The project footprint will also directly impact multiple archaeological sites in the region including a number of mythological locations and some named pools along the Robe River.

Mesa landforms, which are used as landmarks by native title claimants the Kuruma Marthudunera people when travelling though the countryside, could also be disturbed, although Rio Tinto has pledged to avoid such sites where practicable and seek approval under the Aboriginal Heritage Act 1972 if disturbance cannot be avoided.

Under Rio Tinto’s current schedule for Mesa H, construction is slated to begin in the fourth quarter of 2018, once internal and external approvals are attained.

The proposal is open for a seven-day consultation period for submissions by interested parties or individuals on whether or not the EPA should assess the proposal and, if so, on what terms.