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COPYRIGHT: this document remains the property of Pendragon Environmental Solutions; it was prepared for the exclusive use of the authorised recipient(s) and may not be used, copied or re-produced in whole, or in part, for any purpose(s) other than that for which it was prepared for. No responsibility or liability to any other party is accepted by the use of this document without written consent.

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FIGURE 2-10PROCESS WATER SUPPLY LOCATION

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Salt Lake Potash - Lake Way Project Demonstration Plant

Supporting Documentation to EPA Referral

Revision No: 1 Page 31 of 94 Date: March 2019

3 Project justification and Alternatives

SOP is the premium source of potassium (macro-nutrient) favoured by high value, chloride intolerant crops.

SOP has key values over Muriate of Potash (MOP or potassium chloride), such as:

SOP provides both potassium and sulphur in soluble forms.

SOP contains no chloride and hence has a much lower salt index than MOP. Where soils are saline or sodic and where irrigation water may have high chloride levels SOP is the preferred form of potassium to use.

Where seeds or transplants are placed in direct contact with fertiliser, SOP is much less likely to cause root burn of plants.

Potassium stimulates the growth of strong stems and gives the plant some disease resistance by promoting thickness of the outer cell walls. Adequate potassium can reduce moisture loss from growing plants, thereby giving some drought resistance. Potassium improves colour, flavour and storing quality of fruit and vegetables.

Australia currently imports 100% of its potash fertilisers, with 2016 import volumesreported in CRU Fertiliser Week as 273,000 tonnes of Muriate of Potash (MOP) and2015 SOP imports at 72,000 tonnes. When available, a portion of Australian MOP users will purchase SOP.

Asia is the biggest growth region for SOP fertiliser demand and SO4 is well positionedto supply this market. The global demand for SOP, excluding China, has grown from2.2 million tonnes per year in 2010 to 3.2 million tonnes in 2015. The Chinese markethas shown similar growth in demand volumes over the same period. China is expected to continue to be a significant consumer of SOP for the foreseeable future.



Revision No: 1 2 of 94 Date: March 2019

4 Stakeholder engagement

SO4 has undertaken the development of this Project with a clear understanding of the potential environmental and safety risks that the Project may cause; and consequently, what management measures or design implications need to be implemented to effectively treat the risk. As part of defining these risks, SO4 has undertaken a thorough stakeholder engagement. This stakeholder engagement is further outlined in Section 4.1 of this document. SO4 commits to continuing stakeholder engagement during the pre-construction, operations and decommissioning phases of the project.

4.1 Key StakeholdersTable 7 summarises the key stakeholders identified for the Lake Way Potash Project and identifies their interests associated with the project.

Table 4-1: Key Stakeholders for the Lake Wells Project

Sector Organisation Interest

Local Government Shire of WilunaLocal construction and employment opportunities, business development

State GovernmentDepartment of Water and Environment Regulation [DWER]

Environmental impact associated with the development, under both Parts IV and V of the Environmental Protection Act 1986.

Water allocation and abstraction under the Rights in Water and Irrigation Act 1914.

Regulation of emissions from prescribed premises (including solar salt manufacturing)

Land Owner Pastoral Land HolderImpact to operations, construction and employment opportunities

Land Owner TMPACImpact to sites of significance, disturbance to lake body. Employment/ contracting opportunities

State Government

Department of Biodiversity, Conservation and Attractions

Impact on native flora and fauna, including rare and threatened species that may occur in the area.

State GovernmentDepartment of Mines, Industry Regulation and Safety

Resource definition, impacts and disturbance associated with mining activities. Impact to other operations within the area. Mine rehabilitation and closure

State Government Main RoadsLand access to existing road corridors and the areas of potential impact.


Supporting Document to EPA Referral


Sector Organisation Interest

State Government WA HerbariumIdentification and assessment of floristic community types associated with salt lakes, in particular Tecticornia species

Tenement Holder

Active Mining Operation

Blackham Resources Ltd

Impact to operations, agreement for land access, operations and closure.

Neighbouring tenement holder

Toro Energy LtdImpact to future operations. Sharing of data and knowledge

State GovernmentDepartment of Planning, Heritage and Lands

Impact on Heritage Sites, interaction with Native Title owners and relevant management under the Aboriginal Heritage Act 1972

4.2 Stakeholder Engagement ProcessSO4 is working to establish economically, environmentally and socially responsible exploration and mining development at the Lake Way Potash Project. A comprehensive consultation program has been designed and implemented in order to ensure all relevant stakeholders have been identified and effectively consulted with to address potential stakeholder concerns or requirements in regard to the Lake Way Potash Project.

The consultation and engagement program and process was designed to accommodate project options being assessed and enable opportunities for continuing community and stakeholder feedback. Communication tools and consultation methods were designed and targeted to maximise opportunities for feedback from stakeholders, whilst key issues identified and reported through this program were considered in the process of selecting the preferred project options/design.

SO4 has taken into account the knowledge, customs and beliefs of the Traditional Owners, and incorporated their considerations into the design and implementation of the Project. SO4 has worked with the Traditional Owners to identify exclusion areas with respect to the project and incorporated these into the project design. In addition, SO4 has committed to continue to work with the Traditional Owners of this country to ensure any impacts are minimised and approved through the correct mechanisms (i.e. approval under the Aboriginal Heritage Act 1972).

SO4 continue to work with the underlying pastoral and mining tenure holders to ensure that the project does not unreasonably affect their operations. In considering the proposed operation, SO4 have consulted with these lease-holders and incorporated footprint restrictions such that other operations are not affected.




SO4 will continue to engage with relevant stakeholders on matters associated with the Lake Way Potash Project to ensure stakeholder concerns are addressed and that potential impacts will be managed through implementation of industry standard environmental management measures throughout the Life of Mine.

Ongoing stakeholder consultation has been underway since 2017. Key engagement to date is presented in Appendix A. No critical issues were identified during the engagement process.




5 Environmental Impact Assessment and Permitting

5.1 Impact AssessmentPart IV of the Environmental Protection Act 1986 (the EP Act) is administered by the Environmental Protection Authority Services Unit (EPASU) within the Department of Water and Environment Regulation (DWER). Referrals under Part IV of the EP Act define the key attributes of a project and provide sufficient contextual information to enable EPA to identify an appropriate assessment framework, having regard to the potential environmental risks, the complexity and sensitivity of the environment associated with the Project, and the level of public concern about the proposal.

In cases where the EPA considers that a proposal may have a significant impact – andespecially in cases where the potential impacts are not readily assessed and/or managed under other statutory frameworks - the EPA may decide to formally assess a proposal. Alternatively, the EPA may recommend that the proposal be assessed and permitted under administrative systems available under Part V of the EP Act and through other applicable legislation (Figure 5-1).

Figure 5-1: Framework for Environmental Assessments in Western Australia




5.2 EPA PrinciplesThe EPA has identified a set of principles for environmental management. Details of howthese have currently been considered in early Lake Way Potash Project design are providedin Table 5-1.

Table 5-1: Principles of environmental management (Lake Way SOP Demonstration Plant)

Principle Application

Precautionary Principle

Where there are threats of seriousirreversible damage, lack of full scientific certainty should not be used as a reason for postponing measures to prevent environmental degradation.

In the application of the precautionary principle, decisions should be guidedby:

Careful evaluation to avoid, where practicable, serious or irreversible damage to the environment; and

An assessment of the risk-weighted consequences of various options.

A range of studies have been completed over Lake Way by a range of proponents, including but not limited to Toro Energy, Blackham and Apex Minerals. As such, a detailed historical database of Environmental impacts and considerations have been developed and utilised in the development of this referral document.

SO4 has conducted baseline studies and associated impact assessments in a manner that supports an informed, risk-based assessment of the Lake Way proposal.

Environmental knowledge gaps and uncertainty will be explicitly considered during detailed project design.

SO4 commits to the development, implementation and monitoring of measures to prevent unacceptable environmental harm or pollution associated with implementation of the Lake Way Potash Project.

Intergenerational Equity

The present generation should ensure that the health, diversity and productivity of the environment ismaintained or enhanced for the benefit of future generations.

SO4 commits to managing those environmental factors within its control such that future adverse impacts are minimised and that, wherever possible, the quality of the environment is maintainedor enhanced.

A Mine Closure Plan will be prepared for the Lake Way Potash Project in consultation with regulatory and traditional stakeholders to ensure that post mining land use is consistent with agreed stakeholder objectives.

Conservation of Biological Diversity and Ecological Integrity

Conservation of biological diversity and ecological integration should be afundamental consideration.

SO4 has taken into consideration the biological diversity of the lake when designing the project. This includes:

Obtaining specialist input to guide the engineering process.

Locating key infrastructure away from areas of potential environmental significance.

Engineering with the minimum environmental impact as far as reasonably practicable.

The Project will not have any significant or indirect impact on biological diversity or conversation values. No significant flora or fauna will be impacted by this proposal.

Improved Valuation, Pricing and Incentive Mechanisms

SO4 has worked closely with other industry in the Wiluna area to minimise the overall disturbance footprint and utilise existing infrastructure where possible.




Principle Application

Environmental factors should be included in the valuation of assets andservices.

The polluter pays principle – those who generate pollution and waste should bear the cost of containment, avoidance or abatement.

The users of goods and services should pay prices based on the full life cyclecosts of providing goods and services,including the use of natural resources and assets and the ultimate disposal of any waste.

Environmental goals, having been established, should be pursued in themost cost-effective way, byestablishing incentive structures, including market mechanisms, whichbenefit and/or minimise costs to develop their own solutions andresponses to environmental problems.

SO4 maintains an Environmental Management System aligned to ISO14001. The Environmental Management System provides objectives to minimise environmental impact, including procurement and contracting services.

SO4 is currently working with relevant suppliers to obtain organic certification for its operations, providing further value to the overall product and incorporating an environmental conscience into its construction and operation considerations.

Waste Minimisation

All reasonable and practicable measures should be taken to minimise the generation of waste and its discharge into the environment.

Wastes should be managed inaccordance with the following order of preference:

Avoidance.

Re-use.

Recycling.

Recovery.

Treatment.

Containment.

Disposal.

The project has been designed incorporating the following waste minimisation considerations:

Utilise construction materials at source, minimising transport costs.

Utilise HDPE pipework, as this can be recycled and reused more easily than steel pipework.

All waste pipework to be stored and recycled where possible.

Recycling bitterns from the processing for dust suppression, prior to disposal onsite.




5.3 Regulatory frameworkTable 5-2 provides a summary of the anticipated approvals likely to be required for this Project, prior to the project being implemented.

Table 5-2 List of Regulatory Approvals Required for the Project

Regulated Activity Approval Required Legislation (Regulatory Body)

Ground disturbance, mining and processing activities Grant of tenure Mining Act 1978 (DMIRS)

Mining and ore processingApproval to operate via project management plan

Mines Safety and Inspection Act 1994 (DMIRS)

Ground disturbance, mining and processing activities

Mining proposal and mineclosure plan Mining Act 1978 (DMIRS)

Groundwater and brine abstraction 5C licence RIWI Act 1914 (DWER)

Potash production by solar evaporation Works approval and licence Environmental Protection Act

1986 – Part V (DWER)

Ground disturbance in areas of Aboriginal cultural significance Section 18 approval(s) Aboriginal Heritage Act 1972

(DPLH)

Grant of tenure Native Title Agreement National Native Title Act 1993




6 Existing Environment

6.1 Local and Regional ContextThe Project is to be located on mining tenure held by Kimba in proximity to the Matilda gold mining operation (operated by Blackham Resources). Blackham is currently conducting open pit gold mining at the Williamson Pit, under authorisations issued through the Department of Mines, Industry and Resources Safety (DMIRS) in 2018, as well as anEnvironmental Licence under Part V of the Environmental Protection Act 1986.

The project lies within the Shire of Wiluna. The Shire of Wiluna, located approximately 966 km north of Perth, has a total area of 184,000km2 and a population of approximately 720, primarily located within the township of Wiluna, as well as a range of smaller Indigenous communities and mining camps scattered through the region. The shire hosts significant gold, nickel, lead, uranium, iron ore and potash mineralisation.

Other dominant land uses in the area is cattle grazing and tourism associated with the Canning stock route.

The Project is located within the Murchison Region, characterised by undulating hills, occasional ranges of low hills and extensive sand plains in the eastern half. The principal soil type is shallow earthy loam overlying red-brown hardpan, shallow stony loams on hills and red earthy sands on sand plains (Beard, 1990).

6.2 Social SurroundingsEuropean exploration into the Wiluna region first started in 1892 by Lawrence Wells, and gold was discovered in 1896 by Woodley, Wotten and Lennon. This discovery caused a gold rush to the area and the development of the township of Wiluna.

Gold mining in the area caused the town to thrive and prosper, with the population growing to over nine thousand people by the mid 1930’s. At its peak, the town had a regular railway service to Perth, four hotels and many other amenities and facilities.

The beginning of World War II had a severe impact on the gold mining industry and in turn upon the population of the town of Wiluna. Immediately after the war underground mining ceased in the area and gold operations were wound down to virtually nothing. By 1953 only 357 people remained in the area and by 1963 the population had dwindled down even further to about 90 people. Gold mining recommenced in 1981, and investigation into further mineralisation through the area has remained steady since this time.

A review of the 2016 census data for the Shire of Wiluna shows an Indigenous population of 223 persons (or 29.9% of the total population) with the median age of the population being 35 years of age. The 2016 census data also identified a high employment rate (76.8%, or 298persons) being in full-time employment, with the majority of these employed as machinery operators (27.9%) or technicians and trades workers (23.6%). The main employment location




was Gold Ore mining, non-ferrous manufacturing, mining support services and nickel mining (60.6% of those employed).

The Project lies within the determined Native Title Claim area of the Wiluna People (WCD2013/004), managed under the Tarlku Matuwa Piarku Aboriginal Corporation (TMPAC). Connection to culture is strong within the area, with 23.7% of households identifying that the Martu Wangka language was still spoken at home.

SO4 has entered into a Native Title Agreement (NTA) with the Native Title holders for exploration activities and those activities that support exploration. SO4 is currently engagingwith TMPAC, with a view to progressing a NTA for operations of the project.

6.3 ClimateThe Lake Way Potash Project is located within the semi-arid zone of Western Australia, with mild winters and hot summers. The annual temperature regime is characterised by marked diurnal and seasonal fluctuations. A representative Bureau of Meteorology (BoM) weather station for the project is located at Laverton (160 km to the southwest). Mean maximum summer temperatures recorded a range of between 31.9 and 35.8ºC, whilst the mean minimum winter temperature range between 5.2 and 6.6ºC. Monthly evaporation data is shown in Figure 6-1.

Figure 6-1 : Monthly Average Evaporation and Rainfall Comparison, Laverton

Annual rainfall in the semi-arid zone is highly variable and subject to drought periods. Rainfall is related both to locally generated thunderstorms and to dissipating tropical cyclones tracking southeast. Thunderstorm activity tends to be greatest between October and December. Remnant cyclonic activity is greatest between January and May, reflecting the tropical wet season in the north of the state. The average annual rainfall is 233.5 mm, gauged by the Laverton weather station, with the months of May through July showing the greatest number of rain days (BoM 2017). Rainfall is unreliable but tends to fall predominantly

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over the summer months. Occasional thunderstorms in summer bring heavy rainfall and resultant flooding.

The climate is semi-arid. Annual rainfall averages 260 mm/a (SILO database) and annual pan evaporation averages 3504 mm/a. Evaporation exceeds rainfall in all months (Figure 6-2).

Figure 6-2 : Monthly Rainfall and Relative Humidity, Wiluna Township

Mean temperatures range from 30.5°C (mean daily maximum in January) to 12.5°C (mean daily minimum in July) (Figure 6-3).

Figure 6-3 : Monthly Mean Temperature, Wiluna Township

6.4 HydrologyThe surface water catchment is shown in Figure 6-4 and has an area of 11,000 km2. A run-off model was developed for the Lake Way Catchment using the Riverflow2D software

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package. The model was constructed and calibrated to the adjacent and analogous Gascoyne River catchment, and then run using the catchment area defined for Lake Way and rainfall data from the Wiluna Bureau of Meteorology (BOM) station (GWS, 2018). Average calculated annual run-off is 3.9% of annual rainfall but is highly variable.

Figure 6-4 : Lake Way Surface Catchment Area (Knight Piezold, 2019)

The morphology of the playa shape and surface is consistent with the classification system described by Bowler, (1986), shown on Figure 6-5. The northern part of the playa exhibits morphology typical of significant surface water influence and periodic inundation (smooth playa edges, one island). The southern part of the playa exhibits morphology consistent with a groundwater dominated playa with rare inundation (irregular shoreline, numerous islands).




Figure 6-5 : Lake Morphology, From Geoscience Australia, (2013), Originally Developed by Bowler (1986)

The northwest of the playa receives episodic surface water inflow from West and UramurdahCreeks to the north of the playa and other smaller creek lines to the west, this surface water has the potential to cover the entire playa surface with the exception of the raised and dewatered areas surrounding the Williamson Pit (including the causeway that was constructed between the pit and the western shore) in order to mine the Williamson Pit.

6.5 Lakebed GeologyLake Way is a playa salt lake system that has developed on the Carey Paleochannel in the Western Eucla Basin. The paleochannel itself exists along the eastern margin of the playa




with the central, western and much of the northern portions of the playa residing on basement at depths of less than 5 m.

The playa sediments are dominated by red-brown lacustrine clays, indicating the low energy of the depositional environment. Multiple paleosurfaces are evident within the Lake sediments, with characteristics very similar to the current lacustrine and fringing environments. These beds also exhibit dispositional patterns that have allowed changes to the size and shape of the playa over geological time to be interpreted.

Sedimentation appears to have occurred in two distinct phases. Across the playa, sediments from a depth of approximately 1.1 m are firm to hard and notably competent while those at depths of 0 to 1.1 m are soft and puggy. This suggests the lower package of sediments are distinctly older than the upper package. The nature of the sedimentation conforms to a model of geologically recent (Pliestocene to Holocene), phased tectonic uplift that has progressively dammed the Carey Paleochannel.

The shallowness of sediments means that basement is at excavatable depths along thewestern edge of the playa. Basement geology is complex with mafic, felsic and metasedimentary rocks existing in multiple, thin, north-northwest-south-southeast trending lineations. Brine flows from basement contacts is highly variable but, in places, can be very rapid.

6.6 Regional EnvironmentThe Project lies within the Murchison Bioregion of the Eremaean Province of WA in a region known as the Austin Botanical District. The Murchison Region is further divided into subregions, based on the Interim Biogeographic Regionalisation of Australia (IBRA), with the Project located within the Eastern Murchison (MUR1) subregion as shown in Figure 6-6.

The landscape of the Murchison Bioregion comprises low hills, mesas of duricrust separated by flat colluvium and alluvial plains (Commonwealth Government, 2008). It is dominated by the Archaean (over 2500 million years ago) granite greenstone terrain of the Yilgarn Craton (Commonwealth Government, 2008). Alluvial soils and sands mantle the granitic and greenstone units of the Yilgarn Craton. These soils are shallow, sandy and infertile. Underlying the soils in low areas is a red-brown siliceous hard pan (Curry et al. 1994). The soils in the eastern half of the bioregion are typically red sands, calcareous red earth soil, duplex soil and clays. There are 41 vegetation associations (hummock grasslands, succulent steppe or low woodlands) that have at least 85 per cent of their total area in the bioregion. The bioregion is rich and diverse in both its flora and fauna but most species are wide ranging and usually occur in adjoining regions (McKenzie et al, 2002).

The Eastern Murchison subregion comprises the northern parts of the craton’s Southern Cross and Eastern Goldfields Terrains and is characterised by internal drainage and extensive areas of elevated red desert sandplains with minimal dune development. Salt Lake systems are associated with the occluded paleodrainage system. Broad plains of red-brown soils and breakaways complexes as well as red sandplains are widespread. Vegetation is




dominated by Mulga woodlands and is often rich in ephemerals, hummock grasslands, saltbush shrublands and Samphire shrublands (McKenzie et. al., 2002). The Eastern Murchison subregion comprises diverse mulga woodlands, which occur on low greenstone belts. The sand plains have red loamy earths and red deep sands which are found on the sandy banks.




Figure 6-6 : Map of IBRA bioregions in relation to the Project




6.7 Remnant VegetationThe Project is located within the Austin Botanical District within the Eremaean Botanical Province. This botanical district is predominantly Mulga low woodlands on plains, often richin ephemerals, which reduce to scrub on hills. It is also characterised by hummock grasslands, Saltbush shrublands and Samphire shrublands (Beard, 1990). The Eremaean Province is the largest of the three botanical provinces within Western Australia. Thevegetation of the Austin Botanical District of the Murchison Region is predominantly low mulga (Acacia aneura) woodlands on plains and reduced to scrub on hills. This district is often associated with a tree steppe of Eucalyptus spp. and Triodia basedowii on sand plains.

The Department of Agriculture and Food Western Australia (DAFWA) GIS file (2011) indicates that the Project is located within seven Pre-European Beard vegetation associations of the Wiluna System (Table 6-1 and Figure 6-7). The extent of these vegetation associations, as specified in the 2017 Statewide Vegetation Statistics (DBCA, 2017) is provided in Table 6-1.

Areas retaining less than 30% of their pre-European vegetation extent generally experience exponentially accelerated species loss, while areas with less than 10% are considered “endangered” (EPA, 2000). Development within the Project will not significantly reduce the extent of pre-European vegetation.

Table 6-1: Pre-European Vegetation Associations within the Project Development Envelope.

Vegetation

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Wiluna 39 98.8 0 Shrublands; mulga scrub

Wiluna 40 99.00 0 Shrublands; Acacia scrub, various species

Wiluna 125 99.72 0 Bare areas; salt lakes

Wiluna 560 100.00 0 Mosaic: Shrublands; bowgada scrub / Succulent steppe; samphire

Wiluna 561 89.91 0 Succulent steppe with low woodland; mulga over saltbush


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PERTH

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6.8 Groundwater6.8.1 Lakebed SedimentsThe hydrogeology of Lake Way is that of a terminal groundwater sink. The large area of the playa and the shallower water table observed at all sites beneath the playa will facilitate evaporative loss. The brine potash resource extends the full depth of the lakebed sediments with higher permeability noted at the weathered bedrock contact seen in the shallower channel to the west of the island and pit.

Using the historic data, data from the recent sterilisation program carried out by Blackham and the SLP test pits and trenches, where they intersect the base of the lakebed sediments, a leapfrog model of the depth to base of sediments over the development envelope has been undertaken (Figure 6-8). There is a clear thickening of lakebed sediments to the east from a thickness of between 2 and 2.5 m to greater than 4 m and deeper to the northwest.

6.8.2 On-playa pondageAs part of the evaporation process, the ponds will be filled with solidified halite thathas precipitated from solution and built up on the floor on the pond during the life ofthe project. Halite build-up in the ponds is calculated as approximately 0.30m per year; After a 5-year operation, the total height of the ponds will be 2.5m (with 1.5m of halite salts at the base).

At the completion of the project, It is the intention to push down these ponds and return drainage flow pathways back to its pre-development contours, as far as reasonably practicable. Material will be spread within the development envelope such that with flood and rain events, the salt will dissolve and return back into thehypersaline playa groundwater system.

At closure all pumps, pipework and associated infrastructure in and around thep onds will be removed.

6.8.3 Conceptual Hydrological ModelThe conceptual hydrogeological model is shown in Figure 6-9.

The shallow near surface aquifer (0 to 1.1 m) comprises a high porosity, moderate transmissivity sandy clay. Following excavation, flow from this aquifer is initially high but locally it dewaters quickly. Following rainfall, this zone recharges quickly.

The deeper aquifer (1.1 to 5.3 m) consists of several horizons of clay and sandy clay. Whilst the layer is continuous across the Lake locally there are variations that represent differing depositional events.

The aquifer is recharged directly from rainfall and also via surface flow onto the Lake. Recharge is expected to mobilise salts dissolved in the retained porosity of the aquifer and soluble salts within the aquifer matrix. With this recharge mechanism, trenches are expected to yield an ongoing supply of brine at volumetric steady state with




infiltration. Brine concentration is expected to decrease with time as the dissolved and soluble salts are flushed from the system.




Figure 6-8 : Depth to Base of Lakebed Sediments, Lake Way




Figure 6-9 : Conceptual Hydrogeological Model

6.8.4 Brine ChemistryAll brine samples are considered to be composite samples representing the whole excavated or drilled depth at each location. Given that the proposed abstraction techniques will involve trenches excavated to at least 4 m across a large portion of the playa, the use of composite samples is representative of the resource that will be extracted.

The concentration of potassium is quite consistent ranging from 5,910 to 8,760 mg/L averaging 6,596 mg/L.

Nine samples were taken from the Williamson Pit and 47 from across the On-playa Development Envelope. The average brine concentrations are summarised in Table 6-2.

Table 6-2 : Brine QA/QC Results Summary

Brine Supply Location K Cl Na Ca Mg SO4 pH TDS S.G.Parameter mg/L mg/L mg/L mg/L mg/L mg/L units mg/L

Development Envelope 6,596 121,051 73,563 536 7,410 27,502 7 24,3951 1.16

A histogram for the concentration of potassium and magnesium across the development envelope (Figure 6-10 and Figure 6-11) also shows a relatively low variance and a normal distribution with a standard deviation of 1,069 mg/L for K and 1,862 mg/L for Mg.

The resulting dataset was used for interpolation of brine concentration across the playa.




Figure 6-10 : Distribution of Potassium in 2018 Test Pit Samples

Figure 6-11 : Distribution of Magnesium in 2018 Test Pit Samples

6.9 Soil and Landscape SystemsThe Project lies within the Murchison Province and the Ashburton Province of Western Australia.

The Murchison Province consists of hardpan wash plains and sandplains (with some stony plains, hills, mesas and salt lakes) on the granitic rocks and greenstone of the Yilgarn Craton. This Province is located in the inland Mid-west and northern Goldfields between Three Springs, the Gascoyne River, Wiluna, Cosmo Newberry and Menzies (Tille, 2006).

The Ashburton Province consists of hills and ranges (with stony plains and hardpan wash plains) on the sedimentary and granitic rocks of the Capricorn Orogen. This Province is located in the southern Pilbara/ northern Gascoyne between Nanutarra,




Jigalong, Gascoyne River, Wiluna and Lake Carnegie (Tille, 2006). The Murchison Province and Ashburton Province are further divided into soil-landscape zones, with the Project located within the Salinaland Plains Zone (279) and Paroo Uplands Zone (293).

The Salinaland Plains Zone comprises of sandplains (with hardpan wash plains and some mesas, stony plains and salt lakes) on granitic rocks (and some greenstone) of the Yilgarn Craton. Soils include red sandy earths, red deep sands, red shallow loams and red loamy earths with some red-brown hardpan shallow loams, salt lake soils and red shallow sandy duplexes. Vegetation is dominated by mulga shrublands with spinifex grasslands (and some halophytic shrublands and eucalypt woodlands). This zone is located in the northern Goldfields from Lakes Barlee and Lake Ballard to Wiluna and Laverton (Tille, 2006).

The Paroo Uplands Zone comprises of hills, hardpan wash plains and stony plains (with sandplains) on Yerrida, Bryah and Padbury Basins sedimentary rocks and Marymia Inlier granitic and volcanic rocks. Soils include red-brown hardpan shallow loams with red loamy earths and stony soils and some red shallow sands, red shallow loams, red sandy earths and red deep sands. Vegetation is dominated by mulga shrublands (with some spinifex, Eucalypts and halophytic shrubs). This zone is located in the North-eastern Goldfields between Meekatharra, Wiluna and Kumarina Roadhouse (Tille, 2006).

Each zone is further divided into soil landscape systems, with the Project located within six soil landscape systems as shown in Table 6-3 and Figure 6-12.

Table 6-3: Soil Landscape Systems within the Lake Way SOP Demonstration Plant Project

Landscape System/Mapping Unit Description

Carnegie System

(279Ca)

Salt lakes with fringing saline alluvial plains, kopi dunes and sandy banks, supporting halophytic shrublands and acacia tall shrublands.

Gabanintha System (279Ga)

Greenstone ridges, hills and footslopes supporting sparse acacia and other mainly non-halophytic shrublands.

Killara System (279Ki) Basalt hills supporting open mulga shrublands with patchy spinifex.


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PERTH

LEONORA

KALBARRI

MEEKATHARRA

KALGOORLIE-BOULDER

LOCALITY MAP

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ENVIRONMAPS

0 0.5 1 1.5 2

km

LegendLake Development EnvelopeTenement Boundary

Soil Landscape Systems279Bu: Bullimore System: Gently undulatingsandplain with occasional linear dunes andstripped surfaces supporting spinifexgrasslands with mallees and acacia shrubs.279Ca: Carnegie System: Salt lakes withfringing saline alluvial plains, kopi dunes andsandy banks, supporting halophytic shrublandsand acacia tall shrublands.279CaLB: Carnegie Lake Bed Subsystem: Barelake beds inundated for short periods after rain.

279Cu: Cunyu System: Calcrete platforms,intervening drainage floors and channels andminor alluvial plains, supporting acaciashrublands, occasional casuarina woodlandsand minor halophytic shrublands.279Ga: Gabanintha System: Greenstoneridges, hills and footslopes supporting sparseacacia and other mainly non-halophyticshrublands.279Ki: Killara System: Basalt hills supportingopen mulga shrublands with patchy spinifex.279Tn: Trennaman System: Sandy hardpanplains and broad drainage zones supportinggroved mulga shrublands and wanderriegrasses.279Vi: Violet System: Gently undulating gravellyplains on greenstone, laterite and hardpan, withlow stony rises and minor saline plains;supporting groved mulga and bowgadashrublands and occasionally chenopodshrublands.

WILLIAMSONPIT

GOLDFIELDS HWY

GOLDFIELDS HWY

E 53/1905

E 53/2049

M 53/121

M 53/122

M 53/123

M 53/147

M 53/253

M 53/796

M 53/797

M 53/798

M 53/910

E 53/1878

E 53/2057

279Ga279Ga

279Ki279Ki

279Tn279Tn

279Vi279Vi

279Vi279Vi

279CaLB279CaLB

279CaLB279CaLB

279CaLB279CaLB279CaLB279CaLB

279Ca279Ca

279Ca279Ca

279Ca279Ca279Ca279Ca

279CaLB279CaLB

279Ca279Ca

279Ca279Ca

279Ga279Ga

279Bu279Bu

279Cu279Cu

120°20'0"E

120°20'0"E

C:\GIS\Jobs\Pendragon\180025 - Salt Lake Potash Lakeway Referral\Figures\180025_F6-12 Soil Landscape Systems_190228.mxd

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FIGURE 6-12SOIL LANDSCAPE SYSTEMS


- NOTE THAT POSITION ERRORS CAN BE >5M IN SOME AREAS- LOCALITY MAP SOURCED LANDGATE 2006- AERIAL PHOTOGRAPHY SOURCED ESRI WORLD IMAGERY- SOIL LANDSCAPE SYSTEMS SOURCED DPIRD

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