Lake Disappointment SOP Project Public Environmental Review

Background and Context

Global food security is one of the greatest challenges we face as a result of the world’s growing population and the continuous reduction in arable land per capita. In addition, dietary changes prompted by a rapidly growing middle class means that the demand for more sustainable, environmentally friendly fertilisers will increase dramatically.

Reward Minerals believes that its Lake Disappointment Sulphate of Potash (“SOP”, also chemically known as potassium sulphate) Project, which will be a long-term producer of organically certifiable, low-chloride, premium potassium fertiliser, will play an important role in helping to meet this challenge. Potassium is one of the three critical macronutrients needed for plant growth.


Project Introduction

The Lake Disappointment Sulphate of Potash Project (or “LD” for short) is located 340 km east of Newman in the Little Sandy Desert of north-western Western Australia. Lake Disappointment is very large playa, which is a geographic feature typically defined as a dry, vegetation-free, flat area at the lowest part of an undrained desert basin. Playas are generally underlain by stratified clay, silt, and sand, and commonly, soluble salts. Infrequently playas become ephemeral lakes during very wet periods.

LD hosts one of the largest SOP deposits in the world and is characterised by a high average in situ SOP grade. It is located in the best brine evaporative operating environment in Australia, having the highest evaporation rate and lowest precipitation in the country. This means that less brine must be extracted and the evaporation pond footprint can be commensurately smaller than other projects that do not share these attributes.

Holocene Pty Ltd, which holds the tenements upon which LD is located and is a wholly-owned subsidiary of Reward, has a registered Indigenous Land Use Agreement with the Martu people, the traditional owners of the land.  A granted Mining Lease and associated Miscellaneous Licence are also already in place for the Project. A detailed Pre-Feasibility Study was completed in the first half of 2018 which demonstrated that the LD Project will be technically robust and economically attractive.

Reward is committed to ensuring that the Project is developed in the best interests of all its stakeholders. Whilst the State and Commonwealth will clearly benefit from decades of royalties and income taxes, LD is also a great opportunity to maximise training, development, long-term employment and small business opportunities for people living in the surrounding, remote indigenous communities.


lake disappointment body image

Figure 1. Helicopter photograph of Lake Disappointment looking south from the northern shoreline

Figure 2. Helicopter photograph of Lake Disappointment showing the wide expanse of the playa’s salt surface

Figure 2. Helicopter photograph of Lake Disappointment showing the wide expanse of the playa's salt surface


Project Proposal

Potash production at LD will involve the abstraction (pumping) of highly saline brine from trenches excavated in the playa sediments into evaporation ponds where the brine will be concentrated by solar evaporation to crystallise a series of evaporite salts. During the operation the Project’s on-playa footprint will be just over 5% of the total area of Lake Disappointment and after closure and rehabilitation this will drop to below 1.5%.

The project will involve:

  • Abstraction of natural highly saline brines and the concentration of potassium salts in on-playa ponds via the natural process of evaporation;
  • Reagent-free purification of the potassium sulphate in plant to the north of the playa;
  • Storage of halite (salt) in on-playa stockpiles;
  • Abstraction of brackish groundwater from two borefields to supply process water to the plant and accommodation village;
  • Development and use of support infrastructure;
  • Upgrades and minor realignment of existing tracks for use as access/haul roads; and
  • Road transport of potash product.


Environmental Assessment

LD is being separately assessed by state and federal regulators.

The EPA Services Division of the Western Australian Department of Water and Environmental Regulation has approved for release for public review the Environmental Review Document (“ERD”) that Reward has prepared for the Project. The ERD and its supporting appendices, which required extensive water, fauna and flora surveys to be conducted, has taken Reward’s team of employees and environmental consultants (with much guidance from and consultation with the various regulators) approximately four years to compile.

The documents can be accessed on the EPA website (link below) during the public review period which will commence on 4 February 2019 and end on 18 March 2019. Comments on the ERD can be submitted to the EPA for it to take into consideration during its assessment of the project. Details of how to make a submission are provided on the EPA website.