Mangrove Mountain landfill
Background
The Mangrove Mountain landfill is owned and operated by Verde Terra Pty Ltd (Verde Terra).
- October 1998 – Gosford City Council, now Central Coast Council, granted development consent permitting the remodelling of the Mangrove Mountain Memorial Golf Club, and landfilling activities at the site for that purpose.
- November 2001 – we issued an Environment Protection Licence to authorise waste disposal by landfilling at the site.
- 2012-2024 – there have been a series of legal proceedings about the licence and development consent.
- May 2014 – landfilling activities at this site were suspended due to legal actions commenced by Gosford City Council.
- August 2018 – Verde Terra made applications to vary the licence and development consent to permit increased landfilling at Mangrove Mountain. The EPA and Central Coast Council refused and Verde Terra appealed to the Land and Environment Court.
- June 2024 – Verde Terra discontinued both appeals after related legal proceedings found that the development consent did not permit the variations sought.
Regulation of the landfill
Environment Protection Licence review
The EPA regulates the Mangrove Mountain Landfill site through the conditions of their Environment Protection Licence. These conditions are designed to protect the community and the environment and prescribe strict environmental standards for operation.
Our most recent statutory 5-year review of the licence was completed in October 2024 and we are progressing changes to ensure the licence aligns with the review recommendations. This includes improving the effectiveness of environmental monitoring and some onsite management practices, as well as ensuring consistency with contemporary environmental guidelines and the outcomes of legal proceedings.
Prevention Notices – February and May 2025
To further safeguard against any adverse environmental or human health impacts we have issued Verde Terra with a series of Prevention Notices.
The first, issued in February 2025 requires surface water management improvements. This includes the prevention of discharges from the site and the implementation of a water monitoring program to detect potential pollutants, including leachate. A qualified expert must also assess the site’s drainage, landfill capping, and containment systems. This expert will provide recommendations and a clear timeline for any corrective actions.
The second, issued in May 2025 requires a qualified expert to conduct a leachate migration study. This includes a review of current water quality data and on-site containment measures, surface and groundwater monitoring, assessment of environmental risk and options to improve leachate management. This expert will provide recommendations and a clear timeline for any corrective actions.
The Prevention Notices can be viewed on the EPA’s Public register.
We will continue to closely monitor the landfill as part of our on-going compliance activities by undertaking regular inspections to assess the management of water and leachate, including after periods of high or intensive rainfall.
Mangrove Mountain surface water monitoring
In January 2025 we commenced additional surface water monitoring in the unnamed creek next to the landfill to monitor for PFAS, ammonia, and other indicators of leachate. The sampling results are below and will be updated periodically.
| pH | Conductivity (µS/cm) | Biological oxygen demand (mg/L) | Chemical oxygen demand (mg/L) | Ammonia as Ammonia Nitrogen (ug/L) | PFOS | PFOA | Sum of PFHxS and PFOS | |
|---|---|---|---|---|---|---|---|---|---|
| Water Quality Default Guideline Value | 6.5‐8.0a | 125‐2200a | - | - | 20b | - | - | - | |
| Australian Drinking Water Guideline | - | - | - | - | - | - | 0.56c | 0.07c | |
| Ecological Water Quality Guideline (µg/ L) | - | - | - | - | - | 0.00023d | 19d | - | |
| 31 Jan 2025 | DS1 | 7110 | 0.05 | 0.12 | 0.33 | ||||
| 5 Feb 2025 | DS1 | 2500 | 0.026 | 0.083 | 0.23 | ||||
| 25 Feb 2025 | DS1 | 5.98 | 253 | 4 | <10 | 160 | 0.01 | 0.04 | 0.16 |
| DS2 | 6.31 | 228 | 2 | 35 | 400 | 0.01 | 0.06 | 0.19 | |
| 7 Mar 2025 | DS1 | 5.91 | 237 | 5 | <10 | 250 | 0.02 | 0.06 | 0.18 |
| DS2 | 6.33 | 216 | 4 | <10 | 270 | 0.02 | 0.05 | 0.18 | |
| 17 Mar 2025 | DS1 | 5.75 | 234 | 4 | <10 | 140 | <0.01 | 0.04 | 0.14 |
| DS2 | 6.31 | 219 | <2 | <10 | <10 | 0.01 | 0.04 | 0.12 | |
| 28 Mar 2025 | DS1 | 5.70 | 223 | 3 | <10 | 150 | <0.01 | 0.04 | 0.13 |
| DS2 | 6.38 | 213 | 3 | <10 | 90 | <0.01 | 0.04 | 0.12 | |
| 07 Apr 2025 | DS1 | 5.81 | 210 | 4 | <10 | 200 | <0.01 | 0.05 | 0.14 |
| DS2 | 6.37 | 204 | <2 | <10 | 60 | <0.01 | 0.04 | 0.11 | |
| 17 Apr 2025 | DS1 | 6.07 | 234 | <2 | <10 | 140 | <0.01 | 0.04 | 0.12 |
| DS2 | 6.51 | 214 | 3 | <10 | 100 | <0.01 | 0.04 | 0.12 |
The sampling results show some low levels of PFAS detected above ecological water quality guidelines in the waterway immediately adjacent to the landfill.
The presence of PFAS in the environment does not necessarily indicate that there is a health risk, however identifying sites that require investigation is an important precaution to reduce the risk of community exposure to PFAS.
NSW Health advises that water from rivers and creeks should not be used for drinking or cooking without appropriate treatment. Untreated water may contain disease causing micro-organisms, chemical contaminants or algal blooms.
For more information visit Drinking surface water - Water quality (nsw.gov.au) or read our Water quality monitoring – Ourimbah Catchment fact sheet (PDF 935KB).
Broader catchment water quality monitoring
Since 2016, the EPA and the Department of Climate Change, Energy, the Environment and Water (DCCEEW) have conducted broader catchment sampling of Ourimbah Creek and its tributaries further downstream of the landfill to understand water quality in the upper reaches of the catchment.
Information and sampling results can be found here.