Hogan's Pocket Landfill
Hogan’s Pocket Landfill is an accelerated, stabilised, engineered landfill that incorporates stormwater management systems, leachate collection systems, groundwater monitoring wells, biogas recovery fully engineered cells as well as buffer zones between the landfill and the surrounding environment.
Hogan’s Pocket Landfill consists of 3 cells. Cell 1 commenced operation in 2006 and was decommissioned in 2012. Cell 2 was commissioned in August 2012 and Cell 3 in October 2016.
There is no public access to Hogan's Pocket Landfill. Some commercial, industrial and limited regulated waste such as asbestos is directed to the landfill at council's discretion.
The new landfill cell 3
In October 2016 Mackay Regional Council completed construction of cell 3 at Hogan’s Pocket. Cell 3 was constructed in accordance with Australia’s best practice landfill design guidelines to provide maximum efficiency and environmental protection. Cell 3 is expected to provide capacity until 2027 with further cell development (Cell 4) being planned.
Extensive engineering was carried out to ensure the environment was protected. This included a complex engineered liner that incorporates a groundwater diffusion system, compacted clay liner and second geo-synthetic clay liner (double liner).
In addition the base of the landfill is graded so that any contaminated liquids are captured and drained through a sophisticated underground leachate collection network. A second 15 mega litre leachate pond was constructed in 2018 to augment the existing 10 mega litre leachate pond, these ponds have been constructed with four engineered layers of protection. The liner is constructed of compacted clay, geo-synthetic clay and third high density polyethylene (HDPE) plastic liner to protect from leakage. The ponds have a HDPE plastic lid to prevent the infiltration of clean surface water.
All water that comes in contact with waste onsite is collected and gravity fed to this holding facility. This liquid is then recirculated through the landfill cells further enhancing the landfills operating efficiency. This high level of protection provided to the cells and leachate dam ensures no contamination leaves the landfill site.
Control of surface waters
Runoff water is managed by directing sediment laden water into the network of onsite dams. Water that has contacted disturbed soil onsite is channelled into a 30ML sedimentation pond which once full overflows into another 40 ML sedimentation pond downstream via a natural bio-filtration system. This water if required can be recirculated through the dams for further polishing. No water leaves the site unless it meets strict environmental discharge parameters.
All clean water that contacts the upstream catchment of the landfill is diverted away from the landfill footprint ensuring the receiving waters are protected.
The Mackay Regional Council has installed landfill gas capture management at Hogan’s Pocket in accordance with the Waste Management Strategy and Commonwealth Government clean energy legislation. Initially Mackay Regional Council will flare gas to reduce the environmental impact and long term if financially viable will generate electricity from the gas captured.