The possibility of using garbage fumes from the George Town Landfill to produce electricity should be investigated, according to a consultant’s preliminary report on waste management in the Cayman Islands.
A feasibility study to determine whether gas could be “mined” from the sprawling landfill site and used in a waste-to-energy plant is one of the key recommendations in the consultant’s study.
The study suggests a “gas pumping trial” at the site to test power production capacity. It also recommends consultation on the cost of putting infrastructure in place to export the electricity created to the national grid.
The consultants say the current site in George Town will ultimately need to be sealed, covered with topsoil and potentially turned into a park.
They recommend a “capacity study” to determine how much land will be left at the George Town site for landfill once that process has taken place. They also recommend the removal of tires and stockpiled metal from the site. In an assessment of the initial options for the site, consultants Amec Foster Wheeler cautions that even after a new management policy is introduced, landfill space will be required.
“Management of such wastes would need to be in a fully engineered and contained cell, and this land requirement needs to be balanced with demands for other waste treatment processes at the site,” it says.
The consultants were asked not to consider any other sites beyond George Town for a landfill, though government has said that other waste management facilities, including composting and recycling plants, could possibly be located elsewhere.
The potential for waste-to-energy technology to convert landfill gases into electricity has been discussed for some time in Cayman.
The report calls for a full study alongside a cost-benefit analysis.
“There is the potential to collect and recover the landfill gas for combustion in a gas engine to produce electricity and a feasibility study is recommended,” it states.
It warns that the fact that the site is uncapped will make this process more difficult, but concludes it is worth investigating.
“There is the potential for revenues from landfill gas utilization to offset some of the capping and restoration costs, as well as reducing greenhouse gas emissions.”
The consultants also raise the prospect of mining the landfill to provide fuel for a waste-to-energy plant, which typically requires large amounts of trash to run effectively.
They also caution that the “quality” of some of the waste may not be suitable for such an operation and suggest the mining process itself could create a bad odor.
“If landfill mining is potentially feasible, then this would greatly reduce the volume of waste within the site. The downside is that the likely low input rates into a waste-to-energy or similar plant would mean the mining would take place over many years with a consequential delay in final capping and restoration,” it states.
Government released a pair of reports late last week for public consultation. The reports, one an Integrated Solid Waste Management System update, the other a draft National Solid Waste Management Policy consultation document, summarizes some of the work by consultants Amec Foster Wheeler and the options on the table for the island.
The document is mostly broad policy ambitions, including implementing programs to reduce waste production and increase recycling.
One clear recommendation in the report is that people should pay for disposal of the waste they produce.
The document states, “Government is committed to engage and work with all sectors of our community on the 4Rs to reduce the waste we produce, promote waste reuse and recycle wherever this is pragmatic and to otherwise recover energy from the waste that remains. By doing this, we will end our historic over-reliance on landfill and remediate the existing sites, improve the sustainability of waste management practices and work towards a waste conscious population that is empowered to take action and deliver strong and positive contributions.”