Mining of copper at Kapunda inches closer to reality with an ASX announcement made earlier this week of an estimated 119,000 tonnes of copper potentially amenable to ‘inSitu’ recovery at the historic site.
According to tenement holder Terramin Exploration and partner Environmental Copper Recovery SA (ECR), the resource grade is well within the recommended range for ISR operations.
The historic mine site is owned by Light Regional Council.
Terramin and ECR SA entered into an agreement last August regarding the potential development of an in-situ recovery project at the Perry Road site.
The confirmation of the copper resource means progressing to the next stage which includes, continuing base-line environmental water quality testing of surrounding sites, laboratory testing of existing core samples and computer modelling of ground water flows.
“While the planned recovery of copper is still in its initial stages, the announcement is a positive step for the project,” a spokesperson told the Barossa Herald.
Terramin and ECR representatives continue to meet with the council regularly to work collaboratively on the project.
Kapunda Mine background
According to Light Regional Council, the discovery of copper at Kapunda in 1842 led to the establishment of the Kapunda Historic Mine Site in 1844 and this supported the creation of the adjacent Kapunda township.
The mine’s productive life continued through to 1878, with only sporadic activities thereafter until about 1912.
The site has since remained within a mineral Exploration Licence (EL) 5626, which is currently controlled by Terramin Exploration Pty Ltd. There have since been occasional exploration activities undertaken at the site.
The site transferred into council’s ownership during the 60’s and 70’s and its historical significance was recognised through its listing as a State Heritage Place in May 1987.
More recently, Council has invested considerably in several tourism, interpretation and recreation features for the site, supported in part through a state government grant in 2014.
These works have seen the delivery of improved safety fencing around the small number of remnant shafts and other features, including a paved section of pathway between the Perry Road and Mine Street car parks, new shelters and amenities, identification and new excavations of key sites, repointing of newly-exposed stonework and the installation of new interpretive features such as a whim and workhorse sculpture.
Due to its development into a recreation space, council understands that the site is ‘exempt’ from further productive mining and that this exemption would need to be waived to enable such activities to proceed. Beyond this, decisions concerning future mining are made by the state government following its rigorous assessment process.
Midas Environmental Technologies Pty. Ltd. (MET), a predecessor to the ECR Consortium, approached council on occasions between December 2016 and February 2017 to present its proposals for ‘In-Situ Recovery’ (ISR) of a part of the remaining copper mineral resource at the site.
ISR is reported to be a less invasive mineral extraction method relying upon chemical (lixiviant) injection and then extraction of minerals in solution, from which the desired minerals can then be separated.
These presentations gave a broad overview of the technical processes MET/ ECR hope to employ as well as potential employment and other local benefits that may result from a resumption of productive mining at the site.
At its meeting in February 2017, council decided that it would support initial investigations into the feasibility and impact of ISR mining at the Kapunda Mine Site in accordance with established regulatory processes.
The initial investigations presented to and contemplated by the Council related only to water sampling as a part of the initial feasibility analysis for the project.
“The proposal presented by the Environmental Copper Recovery SA Pty Ltd has the potential to add another important chapter to the story of the Kapunda Historic Mine Site,” Mayor Bill O’Brien said.
“However, the site is a significant heritage feature that has evolved into a key tourism and recreation space for the township and these activities need to be sustained without restriction.
“Further, we know that the site lies above the water table which is of critical importance to local ecology and agriculture and cannot risk contamination,” he said.
The proposals for In-Situ recovery of a part of the remaining mineral resource have and will continue to be considered by Council in the context of these paramount community concerns, firstly in terms of initial feasibility activities such as the water-sampling that has been proposed and then for any other activities that may result from that.
“The council looks forward to working with both the proponents and the state government on the further steps involved in evaluating this proposal in accordance with the relevant regulatory processes,” Mr O’Brien said.