Bore ID
Analysis comments
MB11
– Data was only available from April 2023 to September 2024. – Arsenic, cobalt, copper, cadmium, aluminium, manganese, nickel, lead and zinc concentrations consistently exceeded their respective 95% species protection level throughout the entire monitoring period. – Chromium concentrations generally exceeded the 95% species protection level, except during the April 2023, June 2023, September 2024 and March 2024 sampling rounds. – Selenium generally exceeded the 95% species protection level, except during the April 2023, September 2024, March 2024 and August 2024 sampling rounds. – Cyanide concentrations were below the 95% species protection level and the LOR for the entire monitoring period. – EC and TDS exceeded the 80 th percentile value from the EPP throughout the entire monitoring period. – pH was consistently reported below the 20 th percentile value from the EPP. Groundwater sampled at MB11 was found to be highly acidic (pH <3.6) – Aluminium, cadmium, cobalt, copper, manganese, nickel and zinc concentrations consistently exceeded their respective 95% species protection level throughout the monitoring period. – Cyanide and arsenic concentrations were below their respective 95% species protection level the entire monitoring period. All cyanide concentrations were reported below the LOR. – Lead concentrations were generally below the 95% species protection level, except during the June 2023, January to March 2024, June 2024 and August to September 2024 sampling rounds. – Selenium concentrations exceeded the 95% species protection level for all sampling rounds, except during the November 2022, January 2023 and February to September 2024 events. – Chromium exceeded the 95% species protection level during the October to December 2022, March to April 2024, August 2024, November to December 2024, April 2024 and August 2024 sampling rounds. – EC and TDS exceeded the 80 th percentile value from the EPP throughout the entire monitoring period. – pH was consistently reported below the 20 th percentile value from the EPP, displaying highly acidic values (pH <4.6).
MB14
4.2.4 Mann-Kendall statistical trend analysis Results from the Mann-Kendall statistical trend analysis are presented in Appendix D and the trend for each analyte in each bore is summarised in Table 4.2. In total, 15 increasing trends, 15 decreasing trends, 9 probably increasing trends, and 13 probably decreasing trends were identified. An increasing trend was determined by a value having a positive test statistic (S) value with a 95% or greater confidence interval. Trends were determined to be ‘probably increasing’ if showing a positive S value at a 90-95% confidence interval
Table 4.2
Summarised results from the Mann-Kendall statistical trend analysis
Monitoring bore
Analyte
Trend
MB2
Lead Zinc
Probably Increasing Probably decreasing Probably Increasing Probably decreasing Probably decreasing Probably decreasing Probably decreasing Probably decreasing Probably decreasing
MB4-D
Copper Arsenic
Chromium
Cobalt
Lead
Manganese
Nickel
Cadmium Chromium
Decreasing
MB5-D
Probably decreasing Probably decreasing
Cobalt
GHD | Heritage Minerals Pty Ltd | 12638246 | Groundwater Quality Review 2024 20
Powered by FlippingBook