Northern Jarrah Forest South32 Expansion

By the Convenor at WA Forest Alliance

Project: Boddington Bauxite (Worsley) Mine Expansion, South32 Worsley Alumina Pty Ltd

Location: Boddington, Northern Jarrah Forest Bioregion, within the Harris River State Forest

Impact: Northern Jarrah Forest clearing and fragmentation, and loss of threatened and other species’ habitat.

The Northern Jarrah Forest (NJF) is the world’s most biodiverse temperate forest and largest remaining contiguous ecosystem in WA’s southwest biodiversity hotspot.With native forest logging ended, mining is the major forest clearing and fragmentation threat. One example is South32’s bauxite mine expansion near Boddington. Bauxite mining removes the entire forest cover and lateritic subsoil; stockpiled topsoil is later returned, and the mined area replanted with Jarrah forest species.

With the forest substrate gone, ecological restoration of the NJF ecosystems is not possible. Compared to the original habitat, rehabilitation efforts result in a significantly diminished ecological structure, composition and function, reducing habitat quality for already threatened fauna species - counter to their Recovery Plans*.

Over 410 square km of the NJF has been cleared for mining since 1963. This could reach 120,000 square km by 2075 (EPA WA, 2024).

The Boddington bauxite mine expansion will clear 3,885 ha of the NJF, in addition to 13,633 ha previously approved for mining where clearing is yet to begin (EPA WA, 2024).

The Jarrah Forest to be impacted is largely intact, with high species richness and minimal weed invasion (South 32, 2022). Habitat loss will impact eight conservation significant fauna species, and five endangered or critically endangered species, including Forest Red-tailed and Baudin’s Black Cockatoos, Woylie and Western Ringtail Possum.

After a Public Environmental Review, in mid-2024, the EPA recommended conditional approval of the Boddington mine expansion, despite stating "pressures and threats to the NJF are yet to be fully described ... due to limited understanding of complex environmental interactions at a system level, the lack of quality data and information, and the absence of a whole-of-ecosystem assessment."

The EPA has noted significant ‘knowledge gaps’ in government data on the Northern Jarrah Forest and recommended a whole of government approach to respond to these gaps. Recommended conditions require new surveys of conservation significant flora and fauna and future reporting to address past compliance failures and data inadequacies.

The EPA considered renewed rehabilitation efforts and biodiversity offsets sufficient to address ongoing mining impacts. However, rehabilitation is expected to result in only ‘a reasonable degree of ongoing ecological function’. Despite offsets being the ‘least preferred option’, EPA conditions feature many, particularly for threatened fauna species’ habitat losses. This contravenes the IUCN policy that offsets should not allow for processes that risk the further endangerment of threatened species.

An appeal process upheld the EPA’s assessment and, substantially, its recommended conditions (OAG WA, 2024). State and federal government approvals followed.

Recommendations

Ensure projects with likely significant impacts on critical habitat and threatened species are not approved on the condition of offsets

(See also Recommendation 18 under 'Limit Use of Environmental Offsets')

Citations

EPA WA (2024). ’Worsley Mine Expansion – Revised Proposal, Report 1768’. p.6 & 51. EPAWA

South 32 Worsley Alumina Pty Ltd. (2022). ’Worsley Mine Expansion (Revised Proposal) Environmental Review Document. 193.’ EPA WA.

OAG WA (2024). ’Appeals relating to the EPA Report and Recommendations 1768 Worsley Mine Expansion – Revised Proposal, ’Government of Western Australia

* The significant greenhouse gas emissions are not discussed here, nor Aboriginal cultural heritage, nor are the impacts on water resources (see case study 9)