PART 1 — THE CUMULATIVE FOOTPRINT
Gonneville is much more than an open pit.
Its physical footprint extends from a major mine development beside Julimar State Forest through supporting power and water infrastructure across the wider landscape towards Muchea and Alkimos.
The proposal includes the mine, processing facilities, tailings storage, waste-rock landforms, stockpiles, roads and supporting infrastructure together with major off-site water and power infrastructure and transport required to move supplies and product.
This investigation asks a simple question:
WHAT HAPPENS WHEN ALL OF THAT IS CONSIDERED AS ONE CONNECTED FOOTPRINT?
THE SCALE
The EPA's published proposal provides for clearing of up to 940 hectares within a 2,240-hectare Mine Development Envelope, together with up to 664 hectares of disturbance within a 2,034-hectare Infrastructure Development Envelope.
The EPA states that the infrastructure envelope and disturbance are expected to be refined and reduced as the project becomes further defined.
Those figures demonstrate the potential scale.
But hectares alone do not tell us what the whole footprint does to the landscape.
Where does the disturbance occur?
What habitat does it remove?
What does it fragment?
What ecological connections remain?
What happens where linear infrastructure intersects remnant vegetation, waterways and rural landscapes?
And what happens when multiple impacts occur across the same landscape?
That is the cumulative footprint.
CUMULATIVE IMPACT IS MORE THAN CLEARING
Cumulative impacts are required to be considered as part of environmental impact assessment in Western Australia.
Chalice's March 2024 Referral Supporting Document states that a detailed assessment of the cumulative effects of clearing within the local area will be undertaken, considering the successive, incremental and combined impacts of past, present and reasonably foreseeable future actions.
Since then, the EPA has published dedicated Cumulative Impact Assessment guidance.
Importantly, the EPA's approach goes beyond simply adding hectares.
It considers matters including fragmentation, ecological connectivity, edge effects, indirect degradation and linear infrastructure.
That distinction matters enormously for Gonneville.
CLEARING AND FRAGMENTATION ARE NOT THE SAME THING
Two projects could clear exactly the same number of hectares and produce very different ecological outcomes.
Clearing vegetation beside an already disturbed area is not necessarily equivalent to creating a long linear break through vegetation connecting larger habitat areas.
The hectares may be the same.
The ecological consequence may not be.
The EPA's current cumulative-impact guidance specifically recognises linear infrastructure as a contributor to fragmentation and considers the continuity of ecological linkages, interior habitat and edge effects.
So the important question isn't simply:
HOW MUCH WILL BE CLEARED?
It is also:
WHAT WILL THAT DISTURBANCE DISCONNECT?
THE FOOTPRINT STARTS AT GONNEVILLE
The infrastructure corridor is only one part of the picture.
The cumulative footprint begins at the mine itself.
The EPA's published proposal provides for clearing of up to 940 hectares within the 2,240-hectare Mine Development Envelope.
And that disturbance is not simply the open pit.
The proposal also includes processing facilities, tailings storage, waste-rock landforms, stockpiles, haul roads and other supporting infrastructure.
The Mine Development Envelope lies beside Julimar State Forest.
That makes the configuration of the disturbance important.
How much vegetation disappears is one question.
What happens to the vegetation and habitat remaining around and between those major components is another.
TAILINGS AND WASTE ROCK COUNT TOO
Tailings storage and waste-rock landforms form part of Gonneville's physical and environmental footprint.
The approved Environmental Scoping Document requires Chalice to justify the locations of its Waste Rock Landforms, Tailings Storage Facility and stockpiles, taking into account natural topography, ecological function and environmental value.
It also requires groundwater monitoring around the TSF, seepage modelling and consideration of in-pit disposal of tailings.
At this stage, we have not identified sufficiently definitive current public information to confidently state the final physical footprint of the TSF and waste-rock landforms.
We will not speculate.
But these are substantial components of the proposed mine, and their contribution to the overall disturbance footprint matters.
ECOLOGICAL CONNECTIONS MATTER
Chalice itself has previously recognised habitat fragmentation and the importance of ecological connectivity within the wider Gonneville landscape.
Its biodiversity work has discussed restoration intended to address fragmentation and strengthen ecological connections between Julimar State Forest and Moondyne Nature Reserve.
That makes connectivity an important issue when considering the development itself.
The question is not simply what may eventually be restored or offset elsewhere.
It is also:
WHAT REMAINS FUNCTIONALLY CONNECTED AFTER DEVELOPMENT?
THEN THE FOOTPRINT LEAVES THE MINE
Gonneville's footprint does not stop at the mine boundary.
Major off-site infrastructure is required to support the development.
Chalice's current preferred approach includes an approximately 63 km water pipeline from the Alkimos facility to Gonneville and a new approximately 27 km, 132 kV transmission connection between the mine and the SWIS at Muchea Substation.
The infrastructure therefore extends the physical footprint of Gonneville far beyond the mine itself.
Along that route, the surrounding environment and land use change considerably.
Different sections may contain native vegetation, waterways, rural and rural-residential properties, existing infrastructure and already disturbed land.
That distinction matters.
A hectare disturbed in one location is not necessarily environmentally equivalent to a hectare disturbed somewhere else.
To understand the cumulative footprint, it is necessary to understand not only HOW MUCH land is disturbed, but WHERE that disturbance occurs and WHAT it affects.
THE FINAL FOOTPRINT IS STILL BEING REFINED
Chalice says environmental surveys undertaken during 2025 helped inform selection of its preferred infrastructure corridor.
But the preferred route is not final.
Further field investigations are planned for late 2026, and Chalice says the route may still be adjusted before its Miscellaneous Licence application is lodged.
The 100-metre corridor shown on current maps is also not the final clearing footprint.
Chalice describes it as an assessment corridor providing flexibility for infrastructure placement, safe construction access and avoidance of environmental constraints.
The actual disturbance footprint will only be refined once final infrastructure design and survey work are complete.
So while a preferred route has been selected, the precise physical footprint that ultimately determines clearing, fragmentation and edge effects is still being established.
LAND ACCESS MATTERS
There is another important limitation.
Chalice confirms that its 2025 environmental field investigations on private properties occurred where landholders gave their consent.
It is now contacting landholders along the preferred route about further field investigations.
That means there is an important distinction between:
SELECTING A PREFERRED CORRIDOR
and
HAVING THE EVENTUAL DISTURBANCE FOOTPRINT FULLY FIELD-INVESTIGATED AND ENVIRONMENTALLY CHARACTERISED.
Further investigations may provide additional information before environmental assessment is completed.
But the completeness of that final environmental information matters — particularly where the proposed infrastructure intersects retained native vegetation and other potentially sensitive areas.
THE IMPACT DOESN'T NECESSARILY END AT THE CLEARING LINE
Linear disturbance can create a much longer new environmental edge.
The EPA's cumulative-impact guidance recognises indirect effects including fragmentation, edge effects, weeds, dust deposition and degradation of adjoining vegetation.
So the relevant environmental footprint can extend beyond the vegetation physically removed.
Gonneville's cumulative footprint therefore includes not only direct clearing, but the effects that disturbance may have on the environment remaining beside it.
THE IMPACTS DO NOT EXIST IN SEPARATE BOXES
The EPA identified potential effects involving flora and vegetation, terrestrial fauna, inland waters, landforms, terrestrial environmental quality and social surroundings when determining that Gonneville required Public Environmental Review.
But landscapes do not operate as separate assessment categories.
Vegetation clearing can remove fauna habitat.
Linear clearing can fragment habitat.
Fragmentation can affect fauna movement.
New edges can increase pressure on retained vegetation.
Changes to drainage can affect vegetation, waterways and habitat.
And infrastructure, traffic, noise and landscape change can affect surrounding communities at the same time.
One impact can interact with another.
That is precisely why cumulative assessment matters.
THE WHOLE FOOTPRINT IS STILL EMERGING
Gonneville is undergoing environmental assessment.
But significant elements of its physical footprint continue to be refined.
The preferred infrastructure route is not final.
Further field investigations are planned.
The final infrastructure disturbance footprint has not yet been determined.
And substantial mine infrastructure, including tailings storage, waste-rock landforms, processing facilities and roads, contributes to a footprint extending well beyond the open pit.
These facts make one issue particularly important:
THE EVENTUAL ENVIRONMENTAL ASSESSMENT NEEDS TO REPRESENT THE PROJECT THAT WOULD ACTUALLY BE BUILT.
Because cumulative impact isn't simply a calculation of hectares.
Where disturbance occurs matters.
What it fragments matters.
What remains connected matters.
What happens beyond the clearing line matters.
And the interaction between multiple impacts across the same landscape matters.
ASSESS THE WHOLE FOOTPRINT
Protect Our Valley – Chittering believes the community should ultimately be able to see one comprehensible picture of the entire proposal, from the infrastructure network extending towards Alkimos, through Muchea and Chittering, to Gonneville and the edge of Julimar State Forest.
Not just the pit.
Not just the corridor.
Not just the hectares.
The mine.
The waste.
The water.
The power.
The access.
The transport.
The clearing.
The fragmentation.
The waterways.
The indirect impacts.
The communities.
THE WHOLE FOOTPRINT.
THE COMBINED IMPACTS.
THE COMPLETE PICTURE.
ASSESS THE WHOLE FOOTPRINT.
PART 2 — A PROJECT STILL EVOLVING
Gonneville is more than two years into environmental assessment, but the proposal being assessed is still changing.
Since the original March 2024 referral, major elements of the project have been defined, refined or altered. A preferred infrastructure corridor has emerged, parts of the proposed transmission line are now intended to be underground, the disturbance footprint is still being refined, transport corridors remain under design, and Chalice has formally asked both State and Commonwealth regulators to vary the proposal under assessment.
The Commonwealth variation was lodged on 28 August 2026, but the underlying variation material is not currently publicly available.
That creates a simple but important question:
What exactly is being assessed now and how different is it from the project originally referred in 2024?
DEFINED FOR INVESTORS. STILL BEING DEFINED FOR ASSESSMENT.
There is a striking difference between the certainty used to describe Gonneville to investors and the details that remain unresolved in the environmental assessment.
In corporate presentations, Chalice has told investors:
“Water-power solutions and corridors defined.”
It has described Gonneville as “substantially de-risked” and, by May 2026, stated:
“Gonneville approvals are materially de-risked.”
The reasons presented to investors included:
Mine on Chalice-owned farmland — not in State Forest
Strong community support
Government Strategic and Major Project status
Land acquisitions
Water and power solutions and corridors defined
Environmental approvals targeted for H1 2028
But the picture presented through Chalice's own community and approvals information is considerably less settled.
The preferred infrastructure route is not final.
Further field investigations are continuing.
The actual disturbance footprint is still being refined.
Transportation corridors remain in design.
A Miscellaneous Licence for the infrastructure corridor has not yet been determined.
And the State and Commonwealth proposals undergoing environmental assessment are now being formally amended.
These statements may serve different purposes, but the contrast matters.
If water and power corridors were sufficiently “defined” to be presented to investors as part of de-risking the project, affected communities are entitled to ask why important details of the final alignment and disturbance footprint remain unresolved.
MINE ON CHALICE-OWNED FARMLAND BUT THE PROJECT DOES NOT STOP THERE
“Mine on Chalice-owned farmland” is technically a statement about the mine.
It does not describe the entire Gonneville footprint.
Chalice's own current information confirms that, in addition to the mine development area, Gonneville requires an off-site Infrastructure Development Envelope for water and power.
That infrastructure extends across land outside the Chalice-owned mine site.
The WA EPA currently records:
2,240 ha Mine Development Envelope
2,034 ha Infrastructure Development Envelope
Up to 940 ha native vegetation clearing within the mine envelope
Up to 664 ha disturbance within the infrastructure envelope
The Commonwealth referral describes different infrastructure figures:
1,476 ha Infrastructure Development Envelope
Up to 514 ha infrastructure disturbance
Those State and Commonwealth figures should not be assumed to describe exactly the same regulatory footprint without the underlying documents explaining the difference.
But the difference is substantial and deserves an explanation.
And there is now another unknown.
THE FOOTPRINT IS BEING CHANGED, BUT THE PUBLIC CANNOT YET SEE THE CHANGE
On 28 August 2026, Chalice lodged a request to vary the Gonneville proposal being assessed under the Commonwealth EPBC Act.
The Commonwealth portal currently records Gonneville as:
“Considering Variation to Proposal.”
Affected landholders have requested information about that variation, including information relating to the Infrastructure Development Envelope and disturbance footprint.
That material has not been provided to us and the underlying variation documents are not currently publicly available through the EPBC project portal.
The community therefore knows that the proposal under assessment is being changed, but cannot presently independently examine the full details of those changes.
That is a significant transparency gap.
SURVEYS “COMPLETE” — BUT NOT EVERY PROPERTY WAS SURVEYED ON THE GROUND
Chalice states that environmental surveys undertaken in 2025 helped define the preferred infrastructure route and that those surveys are now complete.
But Chalice's own FAQ contains an important qualification.
Field investigations were undertaken on properties where landholders gave consent.
That means “surveys complete” should not be interpreted as meaning every property within the preferred corridor received an on ground environmental survey.
Where access was not obtained, an important question remains:
In Chittering, this is not a hypothetical issue.
The Tree Preservation Area (TPA) crossed by the proposed corridor has not been accessed by Chalice for on ground environmental surveys.
Despite that lack of access, the preferred infrastructure corridor has been identified through this area.
This raises an important question:
What environmental information was relied upon to select the preferred alignment through land that Chalice had not accessed for field survey?
This is particularly significant because the TPA contains protected mature native vegetation and documented habitat values, including black-cockatoo habitat and potential breeding hollows.
What environmental information was relied upon to assess those areas and select the preferred alignment through them?
That matters particularly where the corridor intersects mature native vegetation, potential habitat trees, waterways and other environmentally sensitive areas.
AND TRANSPORT IS STILL NOT DEFINED
The original 2024 proposal contemplated transport using road and/or existing rail.
More than two years later, Chalice's current FAQ still states:
“Transportation corridors are still in design…”
Potential routes continue to be investigated through the approvals process.
So while investors have been told that Gonneville's approvals are “materially de-risked”, a fundamental component of the project's off-site footprint — how its product and supplies will actually be transported — remains under development.
WHY THIS MATTERS
None of these points, individually, proves that an environmental approval process has been breached.
Together, however, they expose a significant gap between the certainty of the investment narrative and the uncertainty that remains for the communities and landholders who may experience the project's off-site impacts.
FOR INVESTORS:
“Gonneville approvals are materially de-risked.”
“Strong government and community support.”
“Water-power solutions and corridors defined.”
“Mine on Chalice-owned farmland.”
FOR AFFECTED COMMUNITIES:
The preferred corridor is not final.
The disturbance footprint is still being refined.
Further field investigations are continuing.
Transport corridors remain in design.
The environmental proposal is being varied.
Affected communities continue to question the claim of “strong community support.”
The Commonwealth variation documents are not currently publicly available.
The mine may be on Chalice owned farmland.
The Gonneville project footprint is not confined to it.
And until the current variation and ultimately the Environmental Review Document are publicly available, communities cannot fully test whether the project being assessed today is the same project they were first shown in 2024, or exactly how its footprint has changed.