Island’s waste policy has reduced methane levels
GUERNSEY is controlling methane emissions from local landfill sites, at a cost of £500,000 a year.
The reassurances comes after methane from rubbish tips around the world have been linked as a major recent factor in increased global temperatures.
A recent report has shown that while worldwide methane emissions now cause a third of global heating driving the climate crisis, Guernsey’s emissions have actually decreased since the States introduced its new recycling and waste policy in 2019.
‘We will have seen a significant reduction in methane emissions from waste locally since 2019, as a result of the elimination of biodegradable waste being sent to landfill,’ said Guernsey Waste senior technical adviser Rob Roussel.
‘Separately-collected food waste and general municipal waste are both now processed and exported for energy recovery, so the only source of greenhouse gas from waste now will be the result of historic disposal operations.’
Scientists have warned that emissions from unmanaged landfills worldwide could double by 2050 as urban populations grow.
The acceleration has alarmed climate experts, who fear it is now the biggest threat to keeping below a 1.5C rise in global temperatures. In August 2020 the States set a target of ‘net zero’ emissions by 2050, with an interim target of a 57% reduction on 1990 levels by 2030.
In 2022, a States report said that waste accounted for around 15% of ‘on-island’ emissions.
Guernsey has an ongoing monitoring regime at three historic and current landfill sites, with gas wells at Mont Cuet, Creve Coeur and Bordeaux monitored weekly or fortnightly.
Mr Roussel said that methane production rates would naturally diminish over time as waste degraded anaerobically.
‘The gas is actively extracted at the current and former landfill sites and then flared off,’ he said.
‘These sites will continue to be actively managed and adjustments made as necessary to maintain gas quality at the flare and prevent over-extraction until the methane concentrations have reduced to a point where it is no longer possible to sustain a flare.’
Mr Roussel added that managing landfill sites was a long-term commitment for Guernsey Waste.
‘Landfill sites continue to be a significant source of emissions for decades after they close. This is a regulatory requirement, and currently costs Guernsey Waste around £500,000 a year.’
