Element 25 Ltd (ASX:E25) has completed pump testing of a water production bore within a shallow (6-16 metre depth) aquifer at the Butcherbird Manganese Project in WA, confirming sufficient process water supply for planned production.
Yields from the aquifer were higher and depths were shallower than previously assumed potentially allowing sufficient water to be recovered from fewer, shallower bores, which will reduce capital and operating costs for the borefield.
E25 managing director Justin Brown said: “Confirmation of the availability of sufficient process water from shallow, high yield, low salinity aquifers at the Butcherbird project is an important de-risking step for project development, which remains on time and on budget.”
Aquifer potential
Several standard pump tests (step test and constant rate tests) were conducted to test the aquifer potential and analysed results using the Cooper-Jacob Method for unconfined aquifers.
A transmissivity at the BBPB03 site of 1,000 square metres /day has now been adopted for modelling purposes.
Samples from test bore BBPB03 were also analysed for salinity.
The groundwater is classified as marginal potable, with a salinity of 1,200 milligrams/litre Total Dissolved Solids (TDS).
This is ideally suited to the proposed processing method at the project.
Groundwater flow modelling
The next phase of work is to undertake groundwater flow modelling to analyse potential borefield designs including the following possible pumping scenarios:
- 4 x 15 litres /second for 6 months, dropping to 25 litres /second total;
- 3 x 15 litres /second for 6 months, dropping to 25 litres /second total; and
- Long term pumping rates of 45 litres /second to support a future expansion in concentrate production.