Hopeland groundwater sampling results and findings
Bore locations map
Former Linc Energy bore sites
Kummerows Road bore sites
Former Mineral Development lease
Former Linc Energy Site – lot 40 DY85
Monitoring bores installed on the former Linc site – findings
In 2017, the Department installed a groundwater monitoring network around the perimeter of the former Linc site. In 2020, this network was expanded to include two bores on the Linc site.
The Linc site is contaminated as a result of undertaking UCG activities, therefore it is expected that levels of benzene, cyanide and other contaminants are above guideline values.
Sampling on the Linc site has shown the presence of UCG contaminants benzene and total cyanide.
These bores are not used for irrigation, or human or stock consumption.
As a result of the groundwater contamination on the former Linc site, it is listed on the Contaminated Land Register (CLR) which recognises that the site is heavily contaminated and requires ongoing monitoring and remediation.
At present, groundwater is generally flowing back towards the Linc site.
Comprehensive results and terminology definitions from groundwater monitoring between 2018 and 2022 are available on the Hopeland environmental management web page.
Data is listed below for benzene and total cyanide levels in the 13 groundwater monitoring bores on the former Linc site since 2018. Benzene and total cyanide levels are the focus of the data on this page because they can be associated with UCG activities.
The tables below include samples collected from the perforated zone of the groundwater well as they are considered the most representative of the groundwater aquifer. The perforated zone is the area of the bore where water passes through. Samples collected from the top of the water column (denoted Light non-aqueous phase liquid (LNAPL) and from the bottom of the water column (denoted dense non-aqueous phase liquid (DNAPL) are not included in the tables below because they are outside the perforated zone.
Results for these LNAPL and DNAPL samples are included in the comprehensive results that can be found on the Hopeland environmental management web page.
*some samples failed quality assurance (QA) checks because the head pressure in the bores required distilled water to be introduced to safely install the pump and reduce gas generation. As a result, diluted bore water was sampled. The Department’s quality control program later determined that these results were not representative of the groundwater.
#sampling for cyanide commenced in early 2021 on the advice of experts.
Note: Some bores were sampled on the same day or on repeated days during the monitoring period. The sampling processes undertaken were conducted at specific phases to check the representativeness of the overall groundwater sampling programs.
Monitoring bores installed on Kummerows Road – findings
In December 2020, as part of the further expansion of the groundwater monitoring network, two additional groundwater monitoring bores were installed in Kummerows Road. Kummerows Road is a narrow road reserve between 20-30 metres wide and the bores are approximately 650 metres west of the boundary of the Linc site.
Sampling of the Kummerows Road bores commenced in April 2021 and the timing of sampling was impacted by sufficient water being present and extreme weather events.
Landholders do not access water from the Kummerows Road bores – they exist solely for monitoring purposes. These bores are not used for irrigation, or human or stock consumption.
Specialists from the Department of Environment and Science have reviewed the results from the Kummerows Road bores and key findings are as follows:
The deeper of the two Kummerows Road bores, shows both benzene and total cyanide contaminants in the groundwater at concentrations that exceed livestock drinking water guidelines (ANZECC, 2000 Water Quality Guidelines) and human drinking water guidelines (NHMRC, 2011 Australian Drinking Water Guidelines). This bore also has naturally high levels of inorganic salts, as measured by the total dissolved solid concentrations, which makes it unsuitable for human consumption.
In April 2021, one groundwater sample collected from the perforated zone of the shallow bore showed total cyanide concentrations above human drinking and livestock drinking water guidelines. This has since dropped to levels below guideline values.
The concentration of contaminants is trending down.
Data is listed below for benzene and total cyanide in the two groundwater monitoring bores located at Kummerows Road.
Monitoring bores installed on private property – findings
Since 2015, more than 130 samples have been taken and analysed from landholders’ bores.
The results of this groundwater sampling have been provided directly to those landowners.
The monitoring within landholder bores has found that Underground Coal Gasification (UCG) contaminants benzene or total cyanide have not impacted the water quality values in landholder bores.
As a result, the current risk to nearby landholders has been assessed as low to negligible.