Lancashire County Council has began a pioneering pilot project with North-West based Positive Biocarbon to remediate soils and store atmospheric carbon using biochar. Biochar is a charcoal-like substance made through a controlled process called pyrolysis that converts organic biomass waste into stable soil carbon. For every tonne of biochar, three tonnes of atmospheric CO2 are captured and carbon is permanently stored when sequestered in soils or building materials.
The project, which sees Lancashire County Council be one of the first local authorities to use biochar, is being conducted at two separate sites: Chisnall Hall, near Chorley, and Midgeland Farm, near Blackpool — a total of six hectares of farmland will be used during the pilot.
Biochar effectively stores carbon and can last for hundreds of years in the soil. When plants and trees decompose, the CO2 captured throughout their life cycle is released back into the air. As biochar can last for hundreds of years in the soil, it is an effective way of removing atmospheric carbon and helping to fight climate change. In just 10-13 years, this project could lock as much CO2 into the ground as a broadleaf woodland of the same size could in 50 years.
James MacPhail, Biochar consultant, said, “This new ground-breaking initiative should create a catalyst across the UK for other local authorities to adopt best practice in soil remediation. It is well documented that offsetting alone cannot combat climate change; we need to look at solutions for capturing carbon too. Not only does biochar creation through pyrolysis — capture atmospheric carbon and store it for hundreds of years — but it also has the physical properties to improve soil quality, enabling previously unproductive land to become useful again.”
“Biochar has been used to great effect for years on remediating soils that are contaminated with heavy metals such as cadmium, lead and zinc, dangerous chemicals, such as arsenic, pesticides and organic pollutants.
“There have been a vast number of international scientific studies into the effect biochar has on contaminated soils. Crucially once the sponge-like structure of the biochar absorbs the pollutants, these aren’t released again. The immobilisation of the contaminants through biochar can lock up 500 times more than soil alone — due to its high surface area, high cation exchange capacity and long residence time in the soil.”
Biochar is recognised as a natural-based solution by the UN Intergovernmental Panel on Climate Change (IPCC), owing to its potential to reduce emissions associated with the decomposition of organic biomass. In addition to capturing carbon, biochar also helps to improve soil quality and increase moisture retention, which can lead to more productive soil for growing grass, crops and trees; this will be particularly beneficial as our summers become hotter. In turn, the increased fertility of the land will mean that plants on it are able to remove more CO2 from the atmosphere.
A recent pilot project also revealed that study samples treated with pine-based biochar experienced a 44% increase in tree biomass compared with control samples. Additionally, some tree species with biochar added to their potting mix displayed increased resistance to stem cankers caused by water mould.
This pilot project is part of a wider environmental strategy by Lancashire County Council, which will also see compost created from the county’s garden waste collections used to plant a one-hectare broadleaf woodland at Chisnall Hall.