Scotland's environment watchdog has confirmed that anaerobic digestion output that is certified under the new PAS110 quality assurance scheme and that satisfies prescribed production and usage criteria will not be subject to waste regulatory controls.  

Already widely used in the water and wastewater sector, anaerobic digestion is becoming an increasingly popular treatment method for biowastes, including food waste. It produces a biogas, which can be used to produce renewable heat or power, and digestate, which can be used to return organic matter to soils. 

The regulatory position, published on the Scottish Environment Protection Agency's (SEPA) website, explains that in certain circumstances formal waste controls will not apply to PAS110-certified digestates, meaning they can be applied to land under controlled circumstances as quality assured products.  SEPA's decision only applies in Scotland, but a similar position has been adopted in England and Wales. 

Enabling certified digestates to be used in this way provides several benefits. Although certification to PAS 110 will bring some additional cost to the operators of anaerobic digestion plants, there will be cost savings to their customers. Specifically, there will no longer be a need to register a waste management exemption with SEPA for the application of PAS 110 certified digestates to land, a saving of £569 per application site.

Clear guidance and the incentive of a deregulated end use should also make it easier for those operating anaerobic digestors to find an end user for their product.   BSI PAS110 is a UK-wide publicly available specification developed in conjunction with the Renewable Energy Association, the Association for Organics Recycling and the British Standards Institute. In Scotland it is supported by both SEPA and Zero Waste Scotland. It is a voluntary, industry led specification, against which producers can check that digestates are of consistent quality and fit for purpose and supports the development of markets for products derived from the digestion of source-segregated biodegradable materials.  

Kenny Boag, SEPA head of Waste Policy, said: 

"There is significant and growing interest in the use of anaerobic digestion technology in Scotland. It is a technology that can help maximise the recovery of value and resource from source segregated biodegradable wastes, principally through the recovery of biogas and high quality soil improvers.

"SEPA is aware that sometimes regulation can be perceived as involving requirements that are not commensurate with the environmental risk attached to the particular operation. By adopting this regulatory position on PAS 110 certified digestates SEPA is satisfied that we may secure the necessary level of protection of the environment and human health in a way that will encourage development and investment in anaerobic digestion technology as a means of dealing with source segregated wastes."