Water sampling – Turon River near Lithgow
Sunny Corner is a historic mining site near Lithgow, 180 km west of Sydney, NSW.
The EPA has undertaken water sampling and testing of samples from waterways downstream of the legacy Sunny Corner silver, lead and zinc mine.
Mining commenced at Sunny Corner in 1875 and continued until 1949. During mining and post closure acid mine drainage has discharged into Daylight Creek. The Department of Regional NSW has invested $ 1.2 million on remediation work at Sunny Corner which has included earthworks to reduce the generation of acid mine discharge from the historical mining site.
Sample locations
Water samples were collected between 31 August and 5 September 2023 from the following sites downstream of the former mine:
- Sample point 1 – Daylight Creek, 1.4 kilometres downstream of the former mine (in-field probe measurements only).
- Sample point 2 – Daylight Creek, 5.8 kilometres downstream of the former mine.
- Sample point 3 – Williwa Creek, 23 kilometres downstream of the former mine.
- Sample point 4 – Jews Creek, upstream of Williwa Creek and not downstream of the former mine.
- Sample point 5 – Woolshed Flat Campground, Turon River, 35.7 kilometres downstream of the former mine.
- Sample point 6 – The Diggings Campground, Turon River, 38.3 kilometres downstream of the former mine.
- Sample point 7 – Turon River Campground, Turon River, 39.7 kilometres downstream of the former mine.
Results summary
There were no exceedances of the Recreational Water Quality Guidelines indicating that the concentrations of these analytes did not pose risks to swimmers or other recreational users.
Dissolved metals are used for ecological assessments as this is the fraction of the metal (the part that is toxic to organisms) as provided in Table 2 below.
Several metals were above aquatic ecosystem health guideline values at Site 2 on Daylight Creek, which indicates a risk to aquatic animals and plants. The elevated metals concentrations in Daylight Creek samples are consistent with, although lower than, sampling results reported in published literature (eg Hayes et al. 2003).
Samples from sites 3 to 7, including the Turon River sites, generally indicated relatively good water quality, with neutral pH, low turbidity, and low concentrations of metals with the exception of zinc. Zinc was elevated at Sites 2 and 3 but was substantially lower at the Turon River sites indicating that concentrations were decreasing downstream of the former mine. The electrical conductivity of the samples from sites 3 to 7 was higher than the guideline value, but this is not unusual for waterways in the region and the Williwa Creek sample was slightly acidic. The Jews Creek sample also had higher electrical conductivity than the sites downstream of the former mine.
Next steps
The EPA is considering the need to undertake additional follow-up seasonal monitoring at recreational locations downstream of the Sunny Corner mine.
Table 1: Recreational Water Guideline values (NHMRC 2008).
| Daylight Creek (Site 1) | Daylight Creek (Site 2) | Williwa Creek (Site 3) | Jews Creek (Site 4) | Turon River (Site 5) | Turon River (Site 6) | Turon River (Site 7) | ||
|---|---|---|---|---|---|---|---|---|
|
Sample date |
5 September 2023 |
31 August 2023 |
||||||
|
Analytes |
Recreational Water Guideline values (NHMRC 2008)2 |
mg/L |
mg/L |
mg/L |
mg/L |
mg/L |
mg/L |
mg/L |
|
Aluminium |
2^ |
- |
0.04 |
<0.04 |
<0.04 |
<0.04 |
<0.04 |
<0.04 |
|
Arsenic |
0.1 |
- |
<0.001 |
<0.001 |
<0.001 |
<0.001 |
0.001 |
<0.001 |
|
Chromium |
0.5 (CrVI) |
- |
<0.001 |
<0.001 |
<0.001 |
<0.001 |
<0.001 |
<0.001 |
|
Cobalt |
No value |
- |
0.0023 |
<0.0001 |
0.0002 |
<0.0001 |
<0.0001 |
<0.0001 |
|
Copper |
20 |
- |
0.055 |
0.0027 |
0.0009 |
0.0016 |
0.0017 |
0.0014 |
|
Lead |
0.1 |
- |
0.011 |
0.0002 |
<0.0001 |
0.0001 |
0.0002 |
0.0001 |
|
Nickel |
0.2 |
- |
0.011 |
0.0012 |
0.0040 |
0.0012 |
0.0012 |
0.0011 |
|
Zinc |
30^ |
6.6 |
0.20 |
0.003 |
0.027 |
0.026 |
0.021 |
|
^No health-based guideline value for drinking water. Based on guideline value for aesthetic (visual/taste) risks for drinking water.
2 NHMRC (2008) Guideline for managing risks in recreational water (suggests 10 x drinking water guideline value can be used to screen recreational water quality)
Table 2: Water Quality Guideline Values for upland river aquatic ecosystems (95% species protection unless indicated).
| Daylight Creek (Site 1) | Daylight Creek (Site 2) | Williwa Creek (Site 3) | Jews Creek (Site 4) | Turon River (Site 5) | Turon River (Site 6) | Turon River (Site 7) | ||
|---|---|---|---|---|---|---|---|---|
|
Sample date |
5 September 2023 |
31 August 2023 |
||||||
|
Analytes |
Water Quality Guideline values for upland river aquatic ecosystems (95% species protection unless indicated) |
mg/L |
mg/L |
mg/L |
mg/L |
mg/L |
mg/L |
mg/L |
|
Dissolved oxygen (% saturation) |
90-110 |
97.8 |
115.1 |
119.7 |
102 |
87.9 |
97.6 |
85.3 |
|
Electrical conductivity (µS/cm) |
30-350 |
<p<>
381 </p<> |
<p<>
191 </p<> |
<p<>
462 </p<> |
<p<>
1370 </p<> |
<p<>
703 </p<> |
<p<>
710 </p<> |
<p<>
689 </p<> |
|
pH |
6.5-8 |
6.0 |
6 |
6 |
8.4 |
8.2 |
8.1 |
8.1 |
|
Turbidity (NTU) |
2-25 |
4.3 |
3.3 |
2.3 |
2.8 |
1.3 |
6.4 |
2.0 |
|
Aluminium |
pH<6.5 (0.0008)+ |
- |
<0.04 |
<0.04 |
<p<> </p<> | <p<> </p<> | <p<> </p<> | <p<> </p<> |
|
Aluminium |
pH >6.5 (0.055) |
- |
- |
- |
<0.04 |
<0.04 |
<0.04 |
<0.04 |
|
Arsenic |
0.013 (AsV) |
- |
<0.001 |
<0.001 |
<0.001 |
<0.001 |
<0.001 |
<0.001 |
|
Cadmium |
0.0002 |
- |
0.024 |
0.0008 |
<0.0001 |
0.0001 |
0.0001 |
0.0001 |
|
Chromium |
0.001 (CrVI) |
- |
<0.001 |
<0.001 |
<0.001 |
<0.001 |
<0.001 |
<0.001 |
|
Cobalt |
0.0014+ |
- |
0.002 |
<0.0001 |
0.0001 |
<0.0001 |
<0.0001 |
<0.0001 |
|
Copper |
0.0014 |
- |
0.41 |
0.002 |
<0.0005 |
0.0009 |
0.0009 |
0.0009 |
|
Cyanide |
0.007 |
- |
<0.004 |
<0.004 |
<0.004 |
<0.004 |
<0.004 |
<0.004 |
|
Lead |
0.0034 |
- |
0.005 |
<0.0001 |
<0.0001 |
<0.0001 |
<0.0001 |
<0.0001 |
|
Manganese |
1.9 |
- |
0.17 |
0.011 |
0.03 |
0.012 |
0.010 |
0.007 |
|
Mercury |
0.00006* |
- |
<0.00005 |
<0.00005 |
<0.00005 |
<0.00005 |
<0.00005 |
<0.00005 |
|
Nickel |
0.011 |
- |
0.0095 |
0.0010 |
0.0034 |
0.0011 |
0.0011 |
0.001 |
|
Selenium |
0.005* |
- |
<0.005 |
<0.005 |
<0.005 |
<0.005 |
<0.005 |
<0.005 |
|
Silver |
0.00005 |
- |
<0.0001 |
<0.0001 |
<0.0001 |
<0.0001 |
<0.0001 |
<0.0001 |
|
Zinc |
0.008 |
- |
6.7 |
0.19 |
<0.001 |
0.019 |
0.017 |
0.017 |
+Low reliability guideline value.
*99% species protection used to account for the bioaccumulating nature of the toxicant.
References
ANZG (2018). Australian and New Zealand Guidelines for fresh and marine Water Quality: Default Guideline Values, http://www.waterquality.gov.au/anz-guideline-values/default
Australian Drinking Water Guidelines (2011) https://www.nhmrc.gov.au/about-us/publications/australian-drinking-water-guidelines#block-views-block-file-attachments-content-block-1
Hayes, W. J., Chaudry T. M., Buckney, R.T., and Khan, A.G. (2003). Phytoaccumulation of Trace Metals at the Sunny Corner Mine, New South Wales, with Suggestions for a Possible Remediation Strategy. Australasian Journal of Ecotoxicology Vol. 9. PP. 69-82.