Changes to the Use of Digestate
Defra has recently announced changes regarding the use of compost from in-vessel composting and digestate from anaerobic digestion. Historically, products resulting from these waste sources could only be applied to organic land where the food waste component of the feed stock was from household waste only. The new interpretation now allows the use of compost and digestate where the feed stock contains food waste from commercial kitchens, including any processing facility that produces food waste. This can include, but is not limited to, establishments that produce ready-made food for retail operations; retailers that dispose of unsold food; mass catering operations, including canteens, restaurants, takeaways; and communal kitchens (i.e. hostels, residential homes).
The facility from which compost is obtained must be a closed and monitored system. In practice, this means the facility must be accredited to PAS 100 standards. The facility from which digestate is obtained must also be a closed and monitored system. In practice, this means the facility must be accredited to PAS 110 standards. The heavy metal limits continue to be the same - the maximum concentrations of certain substances not to be exceeded in mg/kg of dry matter are:
- Cadmium: 0.7
- Copper: 70
- Nickel: 25
- Lead: 45
- Zinc: 200
- Mercury: 0.4
- Chromium (total): 70
- Chromium (VI): not detectable
This change is welcome news and follows on from work that Soil Association Certification and other UK CB’s have done in highlighting to Defra the challenges of the original interpretation.
If you have any questions, please contact your Certification Officer.