Seeding of anaerobic digestion plants

If you comply with the requirements in this regulatory position statement (RPS) you won't need an environmental permit to use digestate, slurries and sewage sludge as a source of bacteria to activate the anaerobic digestion process.

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This Regulatory Position Statement (RPS) was originally developed to cover the use of biologically-active waste sludges and digestates as seeding materials in new crop-fed (i.e non-waste) anaerobic digestion (AD) plants.

Non-waste AD plants are themselves a source of biologically-active seeding materials, and with the significant increase in the number of such plants in England, new operators no longer need to rely on using waste-based seeding materials and so the RPS has become redundant.


Seeding of anaerobic digestion plants: RPS 088

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There is currently no provision in the standard rules permits, or the waste exemptions, to allow the use of waste water treatment sludges or other biologically active sludges to seed anaerobic digestion (AD) plants. This guidance sets out the requirements you need to follow to carry out this activity without an environmental permit.

Published 28 March 2014