Environmental incident assessment and investigation at Ranger and Jabiluka
|March 2015||Exceedance of Magela Creek EC Limit at Gulungul Creek downstream monitoring site||
Supervising Scientist noted deteriorating water quality within Gulungul Creek due to input from Gulungul Creek Tributary 2 (GCT2) during the 2013–14 wet season. There has been an increased impact on water quality during the 2014–15 wet season resulting in an exceedance of the chronic (>72 hour) Magela Creek EC Limit at the Gulungul Creek downstream monitoring site during March 2015.
SS has deployed additional monitoring equipment and monitored an increased number of sites in Gulungul and Magela Creeks this wet season to investigate the impact of GCT2 water downstream. We have conducted additional in-situ toxicity monitoring during the 2014–15 wet season including a site just downstream of where GCT2 enters Gulungul Creek.
SS will conduct recessional flow biological monitoring in Gulungul Creek during 2015, which will include the assessment of macroinvertebrates and freshwater mussels in Gulungul Billabong.
Background to incident investigation
The rules for reporting incidents have varied over the life of the mine but the current system under the Environmental Requirements (ERs) has been in force since 1 January 2000, and states that:
The mine operator must directly and immediately notify the Supervising Authority, the Supervising Scientist, the Minister and the Northern Land Council of all breaches of any of these Environmental Requirements and any mine-related event which:
- results in significant risk to ecosystem health; or
- which has the potential to cause harm to people living or working in the area; or
- which is of or could cause concern to Aboriginals or the broader public.
Immediately upon receipt of notification of a mine related event the Supervising Scientist Division (SSD) assesses the circumstances of the situation and a senior officer makes a decision on the appropriate level of response. Dependent on the assessment, this response will range from implementation of an immediate independent investigation such as occurred in March 2004 following a potable water contamination incident, through seeking further information from the mine operator before making such a decision. In those cases where immediate action is not considered to be required the situation is again reviewed on receipt of a formal incident investigation report from the operator.
In addition to these statutory requirements for incident reporting Energy Resources of Australia (ERA), the mine operator, has since 2000 undertaken to provide stakeholders with a comprehensive list of environmental issues reported at its Ranger and Jabiluka operations on a monthly basis. This regime of reporting all recorded environmental issues is undertaken voluntarily by ERA in response to concerns expressed by stakeholders about the establishment of suitable thresholds of incident severity for reporting.
Prior to each Routine Periodic Inspection (RPI) the inspection team reviews the previous month's reports and any open issues. Where issues are considered to have any potential environmental significance or represent repetitions of a class of occurrences an onsite review is scheduled as a part of the RPI protocol.
- Audits and inspections (Routine Periodic Inspection)
Incidents this reporting period
The SSD prepares a report for the Alligator Rivers Region Advisory Committee which meets twice a year. Table 1 shows the environmental issues reported to SSD for the period April 2014 to June 2014. Several reported issues were investigated by SSD through the RPI process. All information provided through the RPI was deemed to be satisfactory and no further follow up action was required. No reportable incidents or environmental issues occurred at the Jabiluka site during the reporting period.
To allow for ease of interpretation and presentation the issues have been grouped into general location of occurrence and type and presented in Table 1.
¹ Processing area incidents occurred in the SX, sand filters, calciner, CCD and product packing