Groundwater Monitoring
Groundwater monitoring has been undertaken at Tamala Park since 1998. The purpose of the groundwater monitoring program is to:
- Detect leachate reaching the groundwater;
- Determine the direction of groundwater flow;
- Assess the quality of the groundwater; and
- Determine the migration of any leachate plume.
Ground water management at the Tamala Park Landfill site
The Mindarie Regional Council (MRC) has been managing the Tamala Park Landfill site since the early 1990s. The facility is regarded as a best practise landfill operation.
Landfill sites are known to potentially impact on the quality of the surrounding groundwater, as substances leach from the waste that has been landfilled.
Modern landfills have liners which help prevent the contamination of the surrounding soil and groundwater. The earliest part of the Tamala Park landfill was an unlined landfill, while the more recent parts of the landfill are lined.
The Tamala Park landfill complies with all of its Department of Water and Environmental Regulation (DWER) requirements including licence conditions. Current DWER requirements include the commissioning of an independent review of potential issues resulting from the landfill, the Mandatory Auditor’s Report (MAR or the Report).
The completed MAR identifies some potential issues if the MRC did not continue to operate with its high level of diligence on these matters. The MRC accepts the findings contained within the MAR and has already made progress in implementing the recommendations.
The review’s findings and recommendations include:
- Continued use of personal protective equipment by MRC employees on site
- Continued monitoring of landfill gas and groundwater
- Groundwater not be used for drinking purposes without appropriate treatment and testing to confirm its suitability
- No further property development to the immediate north of the landfill site (in the buffer zone land)
The MRC considers the Report to be an accurate reflection of the potential risk presented by groundwater contamination and landfill gas migration as they relate to the Tamala Park site and surrounding areas. Additionally, the recommendations within the report are considered reasonable and achievable, and most of which support or enhance existing monitoring practices, or are procedural in nature.
Based on the current understanding of these risks, the Report does not recommend any remediation works to either the Tamala Park site or to the Catalina Regional Council’s (CRC) land immediately north of the Tamala Park site.
The Report has also not identified any immediate risk to human health, citing that ‘at this time, it is not possible to confirm a risk to the environment or human health.’ Rather, the report has identified a potential unacceptable risk to human health should the identified issues related to groundwater contamination and landfill gas not be adequately addressed.
This view is consistent with the MRC’s internal risk assessment.
The MRC considers the implementation of all recommendations contained within the Report to be a matter of priority in order to further understand and assess any potential risks.
Mandatory Auditor's Report.