Inverbrackie Creek Catchment Group E: [email protected] M: 0418 892 569 Project: Bird in Hand Gold Project Applicant: Terramin Exploration Pty Ltd (ACN 122 765 708) Application: Mineral lease; Miscellaneous purposes licence Mineral claim (MC) number: MC 4473 Purpose: Recovery of gold and silver; Ore processing and tailings storage facilities Reference: 2019/1021; 2019/0826 Introduction Without farmers, the world is hungry, thirsty and naked. Farmers farm because we love the land, and we care for our soils, our crops, our livestock. Agriculture also needs water. Cities need water. We all need water! This presents a challenge for farmers in much of the Mount Lofty Ranges, which is part of the city of Adelaide’s watershed. Over the last 40 years there has been increased focus on local farmers to ensure our management protects the quality of water leaving our properties. This was a catalyst for the formation of the Inverbrackie Creek Catchment Group, which since 1992 has focussed on protecting Adelaide’s watershed via water and watercourse monitoring, land management education, willow and woody weed eradication, fencing riparian zones, reduced cultivation, and extensive revegetation and farm forestry. Underground water is a precious resource in the Mount Lofty Ranges and is strictly regulated by the State Government. After a contentious moratorium that resulted in some community adjustment to regulation in this space, a Water Allocation Plan (WAP) for the Western Mount Lofty Ranges Prescribed Water Resources Area (WMLR PWRA) was adopted in 2013. Water resources are now fully allocated in the WMLR PWRA. 1 The vast majority of Australian farms are family businesses, spending much – at times all – of their income into local businesses, suppliers, advisors; and of course, the Australia Taxation Office. While farmers recognise that mining is an important contributor to a developed world and to the economy, to most of us mining companies are somewhat faceless, financially iffy entities whose favourite activity is to dig holes across our land in the search of some shiny stones. We have such a situation in the catchment of the Inverbrackie Creek. The immediate area around this proposed mine is one of South Australia’s most picturesque and productive districts. It has grown and sustained generations of family businesses that are now producing hundreds of millions in economic activity, jobs, tourism and exports every year. And it is also part of the Onkaparinga River watershed that provides 60% of Adelaide’s drinking water. Our concerns are myriad and significant. Our district sits on a fractured rock aquifer system that provides the water needed to sustain the area’s critical agriculture, horticulture, winemaking and tourism businesses. Due to there being no mains water, households also depend on the aquifer for domestic use. Within 5km of this proposed mine there are a range of crops grown – strawberries, apples, brassicas, beef, sheep, alpacas, horse studs, turf, hay two plant nurseries (ornamentals and fruit trees) and wine grapes. Terramin Australia (TZN) is proposing to dig for gold in this environment, through the aquifer, and immediately next door to these businesses. Gold is a somewhat useless mineral, with just 10% being used industrially. This proposed mine will operate 24/7/365, creating noise pollution, dust, great piles of mullock, 74 additional traffic movements per day, and – most critically – it will impact the fragile aquifer that underpins this whole ecosystem. And this is all for just five years of potential production, temporary jobs and minimal royalties for the State. Terramin’s basic premise is that they will need to pump out 400 megalitres of groundwater around their mineshaft to keep it dry, so they plan to re-inject treated water at high pressure back underground away from their workings. Trying to force a megalitre of water every day into a basin-type aquifer is achievable, but with a fractured rock aquifer it is virtually impossible to know – or even to model – what is happening 2 underground and where the water is ending up. This raises real concerns about changes to water levels and salinity. There are two strawberry farms near the mine, one less than 2km away, and strawberries are intolerant of irrigation water with a salinity of greater than 500ppm. During Terramin’s reinjection trial, after 11 days of pumping water back into the aquifer a bore 980m away had its level rise almost a metre – and it is simply impossible to extrapolate that result over five years of mining, so who knows what our water availability and quality will be like after 1,460 days of mining. Terramin’s previous mine at Strathalbyn spent most of its operational life out of compliance, mostly around water management. The modelling was wrong ,and they found approximately ten times more water than expected. This company is also now wanting to rework a historic gold mine near Palmer, only a few kilometres from some cropping land of ours, and again, water ingress was a contributor to previous companies abandoning the project. Despite asking constant questions of the proponent through the Woodside Community Consultative Committee, we have no confidence in Terramin’s ability to undertake this mine at Woodside in a way that will not harm the area’s unique environment and the families, businesses and communities who depend on it. Their 2018 Full Year Financial Results showed that Terramin lost another $5.6 million, taking accrued losses to $175.5 million. And the stock market has not shown great excitement over the submission of their Mining Lease Proposal, with shares dropping from 8.5c to 5.7c since lodgement. Yes, there have been historic gold mines in our district, mostly mined in the 1880s and the 1930s, but few of these companies survived more than a few years – the mines always ended up flooded when miners penetrated the aquifer. The Bird-in-Hand mine has a well-documented history of water management issues. Flooding closed operations when the mine was twice opened in the late 1800s and again in 1934, similar to surrounding historic mines. Yes, landowners around Woodside know there is always the risk of a gold mine opening again as for years companies have poked around looking for 3 something shiny, but given the enormous agricultural value of the land, and the catastrophic risks that mining poses, it is simply ludicrous that any company attempts to mine this area again. It is not worth the risk. There is no place for mining on highly productive agricultural land, and no place for mining in a capital city’s watershed. The vast majority of SA’s land is not in a city’s watershed, and not on agricultural land – and in these locations, mining is often the most economic use of the land. However, the world needs food and drink far more than it needs handfuls of stones. 4 Key concerns: Water TZN plans to extract and reinjection around 450ML of water per annum to keep the mine dry. This is almost half the total amount of water available to irrigators in the Catchment (Fig 1), meaning that any failures in the reinjection process, or worse, in the structure of 5 the underground workings resulting in underground flooding, poses a catastrophic risk to existing water users. Figure 1: Inverbrackie Creek Catchment water balance. Source: DEWNR The Inverbrackie Creek sits on a fractured rock aquifer (Figure 2), meaning that the hydrology is extremely variable and complex, making hydrological modelling difficult. Fractured rock aquifer systems are extremely complex, often compartmentalised and flow occurs preferentially along fractures. These attributes make it very difficult to reliably predict the subsurface movement and likely drawdowns/injection pressures that will be generated using groundwater numerical models. Porous media Fractured rock 200989-001 Figure 2: Comparison between a basin-type aquifer (left) and a fractured rock aquifer (right). Source: DEWNR 6 In a fractured rock aquifer water occurs within geological fractures, making water chemistry variable depending upon the rate of movement and the chemical composition of the surrounding rock. Thus, adjacent bores can have substantially different water chemistry and water flows, depending on the chemical composition of the regolith, the downward infiltration of rainfall, the size of the fractures, and the pressure created by surrounding fractures. This variation is illustrated in Figure 3. Figure 3: Groundwater yields and salinity levels are highly variable across the Western Mount Lofty Ranges, especially around Woodside. East of the red line is the Easter Mount Lofty Ranges Catchment. Source: DEWNR Groundwater numerical models are a mathematical approximation of the natural subsurface system and require various assumptions to be imposed in order to mathematical represent the complex natural system. Unfortunately, across industry there is an over reliance on the results of numerical modelling to provide definitive answers (please refer to Attachment 1 - groundwater modelling uncertainty). 7 TZN obtained water samples from investigation bores and from a number of private wells. Although much of the groundwater within the catchment is of relatively low salinity (most bores are less than 1500 mg/L TDS – which is still too high for strawberries and brassicas), some areas of higher salinity exist, particularly to the southeast of the mine site. However, based on data contained in Appendix C1 and C2, there are also areas of saline water (> 3000 mg/L) much closer to the mine site than depicted in the regional groundwater salinity map. It is unclear why this data (e.g., from 6628-23530 and 6628- 8301) is not discussed in the report and omitted from the map. It suggests that a more thorough understanding of the distribution of water quality in the regional aquifer (including how it changes with depth) is Critical water quality parameters (natural organic matter, total organic carbon, dissolved oxygen, redox potential and microbiological indicators) that would inform the geochemical reactions that would take place when oxygenated water from the surface storage pond and treatment process have not been collected before, during or after the reinjection trial.