Remediation of the George Town Landfill could turn Mount Trashmore green in more ways than one. Not only will capping the mound include a layer of topsoil that will one day support the growth of grasses and shrubs, but remediation will also reduce the Cayman Islands’ impact on global warming.
Martin Edelenbos, the solid waste management engineering coordinator with the Decco Consortium — the preferred bidder to implement the integrated solid waste management system — explains there are two main ways in which remediation of the George Town Landfill will lessen the country’s impact on climate change: through the reduction of methane emissions and methane utilisation.
Globally, landfills are a top source of methane, a potent greenhouse gas that is 28 to 36 times more effective than carbon dioxide at trapping heat in the atmosphere.
“After carbon dioxide, methane is the most widespread greenhouse gas,” Edelenbos says. “Methane makes up approximately 50% of landfill gas. Remediation will ensure less of this powerful climate forcer is released into our atmosphere.”
Since the Industrial Revolution, methane concentrations in the atmosphere have more than doubled, and approximately 60% of the methane in the atmosphere today comes from sources scientists think of as human-caused.
Remediation of the George Town Landfill will include a network of collection wells and pipes connected to a gas blower to collect the landfill gas created when organic waste biodegrades. When the planned waste-to-energy plant is commissioned, the collected landfill gas will be piped to the facility for energy recovery through the waste combustion boiler. The electricity generated from the methane will avoid the use of fossil fuel generators to produce the same amount of power.
In the meantime, the landfill gas will be flared off to destroy odorous or noxious compounds, as well as methane. The flare will be located beside the waste mound and stand approximately 10 to 15 feet tall. Landfill gas will be burned within the flare stack to avoid a visible flame and ensure complete combustion.
Throughout the process, safety and efficiency will be ensured by monitoring the landfill cap for gas emissions and by controlling the gas extraction process.
It is anticipated that, once the mound has stabilised sufficiently, walking paths will be installed at the site of the remediated landfill.
“Similar remediation projects have been successfully completed around the world, such as the Keele Valley Landfill that the high school Dart Scholars visited on an enrichment trip in 2018,” Edelenbos says. “The garbage has been covered by a thick layer of soil and plants, which has transformed the area into a green space that has both environmental and community value.”
Remediation of the George Town Landfill began earlier this year and will continue in stages until the energy recovery facility is commissioned.
This article appears in print in the September 2020 edition of Camana Bay Times.