In December 2019, the Transition to Action program visited Goondiwindi to scope possible circularity projects in this regional town of Queensland.
Transition to Action was a collaborative program between circularity specialists Coreo, the Queensland Government’s Department of Environment and Science and the local people of Goondiwindi. From this T2A program the Goondiwindi Circular Cotton Project was born.
The project became a collaboration between Coreo, the Queensland Government, local brand Goondiwindi Cotton, cotton farmer Sam Coulton, Sheridan, Cotton Australia and Cotton Research and Development Corporation supported soil scientist Dr Oliver Knox of the University of New England.
The mission was to to test whether shredded cotton products at end of life could be returned to the cotton fields, offering both benefits to cotton soil health, and a scalable solution to textile waste.
Read the Transaction to Action report on circular economy here.
Phase 1: lab tests
Back in 2020, Phase One of the project involved lab-based testing cotton fabrics to assess what might happen during the biodegradation process, in terms of potential benefits such as carbon and water retention in soils.
The results of the Phase One lab tests, analysed by Dr Oliver Knox with support from the Cotton Research and Development Corporation, showed:
• Adding cotton fabric samples to soil increased levels of microbial (bacterial and fungal) activity in all but one sample.
• When added to soil all but the tightest weave of cotton material broke down significantly in about 24 weeks.
• Cotton seeds germinated just as well in soil to which cotton fabric had been added as it did in soil to which no material had been added.
These results encouraged the team to move to a field trial which was implemented during the 2021-22 cotton season.
Phase 2: field trial
In June 2021 around two tonnes of cotton textiles, garments and end of life State Emergency Service coveralls were processed at Worn Up in Sydney, transported to "Alcheringa” farm, and spread onto a cotton field by local farmer, Sam Coulton. The field was being prepared for planting the next cotton crop in October 21. It was
hoped the fabrics would break down in the soil, increase microbial activity, lock in carbon and provide cover to improve soil moisture.
Projections showed 2,250kg of atmospheric Carbon Dioxide equivalents (CO2 e) would be mitigated through the breakdown of these garments in soil rather than landfill.
The trial looked at the breakdown process at different application rates, and assessed effects on soil nutrition, respiration/CO2 and microbial biomass.
The trial was concluded at cotton harvest in May 2022, with initial results reported here, although it’s expected the real benefits for cotton yield and long-term soil health may not be known for many years.
Read the Circularity Project report here.
Next Steps
There is much interest in further collaboration from industry groups, government, farmers, brands and potential investors. In order to establish the feasibility of this approach as a scalable solution to cotton textile waste, more research is required as a next step.
Year 2 Trials
Due to Covid and floods we recognise that the first trial wasn't perfect. We’re excited to announce that the trial will be replicated during the 2022-23 cotton season, with an additional farm in Gunnedah NSW added as a trial site.
Sheridan is providing at least 10 tonnes of shredded cotton textiles for these trials. This will give us further confidence that the results we’ve already seen can be replicated across time and geographies.
CRDC Commits to Compost Research
The Cotton Research and Development Corporation (CRDC) has committed to funding cotton textiles composting research that will further investigate the effects of dyes and finishes and look at ways to pelletise cotton textiles so it can be spread on fields using existing farm machinery. This is a three year commitment from CRDC with approx $300,000 investment.
Want to Get Involved?
Any group or individual interested in collaborating can contact the team.