Radium-226 (i) Undertake routine sampling - - - 3 mBq/L (i) The wet season geometric mean total for Radium-226. activity concentration measured at the downstream compliance sites minus that (ii) Report and act on Trigger (wet season measured at the upstream control sites is not Value exceedances at the geometric mean greater than the Limit. downstream compliance sites. difference between (ii) All Trigger Value exceedances are (iii) Minimise mine derived compliance and investigated and reported as outlined in Section radium-226 at the downstream upstream sites) 4 of the Revised Water Quality Objectives for compliance sites to the greatest Magela Creek and Gulungul Creek (2015) extent practicable. Invoked by Trigger Value “Actions Exceedances”. (iii) Radium-226 activity concentrations will not deteriorate compared to those measured in previous wet seasons, without reasonable cause. 6 Guidance for continuous monitoring and event-based sampling methods. Methods Purpose Control Event-based Sample Event-based sampling should be implemented to ensure that each EC pulse ERA should provide details of their sample collection methodology in the Annual recorded by the continuous monitoring system is sufficiently chemically Water Management Plan for stakeholder approval. Collection characterised to allow effective assessment against the relevant Trigger Values. Total metal concentrations should be converted to equivalent dissolved metal Total concentrations of metals and major ions should be measured by acidifying concentrations by use of the appropriate concentration conversion factor prior to unfiltered samples to 5 per cent nitric acid and digesting them at 100-110 ºC for a comparison with the Ranger Water Quality Objectives. Details in Section 3.5 of minimum of six hours, prior to analysis. the Revised Water Quality Objectives for Magela Creek and Gulungul Creek (2015) Interpretation and Reporting”. “Data Continuous Monitoring Continuous monitoring data for EC, turbidity and pH should be recorded at a ERA should provide details of their data recording methodology in the Annual Data frequency that provides assurance that the full magnitude of a given pulse will be Water Management Plan for stakeholder approval. captured to an environmentally relevant resolution.
Radium-226 (i) Undertake routine sampling for Radium-226. (ii) Report and act on Trigger Value exceedances at the downstream compliance sites. (iii) Minimise mine derived radium-226 at the downstream compliance sites to the greatest extent practicable. - - - 3 mBq/L (wet season geometric mean difference between compliance and upstream sites) (i) The wet season geometric mean total activity concentration measured at the downstream compliance sites minus that measured at the upstream control sites is not greater than the Limit. (ii) All Trigger Value exceedances are investigated and reported as outlined in Section 4 of the Revised Water Quality Objectives for Magela Creek and Gulungul Creek (2015) “Actions Invoked by Trigger Value Exceedances”. (iii) Radium-226 activity concentrations will not deteriorate compared to those measured in previous wet seasons, without reasonable cause. 6 Guidance for continuous monitoring and event-based sampling methods. Methods Purpose Control Event-based Sample Collection Event-based sampling should be implemented to ensure that each EC pulse recorded by the continuous monitoring system is sufficiently chemically characterised to allow effective assessment against the relevant Trigger Values. Total concentrations of metals and major ions should be measured by acidifying unfiltered samples to 5 per cent nitric acid and digesting them at 100-110 ºC for a minimum of six hours, prior to analysis. ERA should provide details of their sample collection methodology in the Annual Water Management Plan for stakeholder approval. Total metal concentrations should be converted to equivalent dissolved metal concentrations by use of the appropriate concentration conversion factor prior to comparison with the Ranger Water Quality Objectives. Details in Section 3.5 of the Revised Water Quality Objectives for Magela Creek and Gulungul Creek (2015) “Data Interpretation and Reporting”. Continuous Monitoring Data Continuous monitoring data for EC, turbidity and pH should be recorded at a frequency that provides assurance that the full magnitude of a given pulse will be captured to an environmentally relevant resolution. ERA should provide details of their data recording methodology in the Annual Water Management Plan for stakeholder approval.
ir638.docx