Scottish sludge incineration strategy under fire

Environmental groups have complained to the European Commission about a decision by East Of Scotland Water (EoSW) to burn sewage sludge, instead of spreading it on land.

EoSW originally planned to dispose of Edinburgh’s sewage sludge by using it on agricultural land after treatment at its new plant at Levenmouth in Fife, but the company has since opted for incineration.

Friends of the Earth (FoE) and the Scottish Wildlife Trust (SWT) believe that EoSW has failed to compare the environmental benefits of the two options and is therefore in breach of European law on sewage treatment.

Dr Richard Dixon, head of research at FoE Scotland said: “It was a real surprise that EoSW went for the wrong option after choosing to use the sludge from Edinburgh on land, particularly since Fife has plenty of suitable agricultural land.”

“We are asking the EC to step in and, if necessary, require the Scottish Parliament to reverse the Levenmouth decision.”

In a joint report last year, both groups argued that re-use of treated sludge on agricultural land would be the best option in most cases. It maintained that incineration would waste nutrients and create air pollution and toxic by-products, which could end up in landfill sites.

However, EoSW now plans to burn sludge at Scottish Power’s Longannet power station, under a 40-year private finance initiative (PFI) scheme.

West of Scotland Water (WoSW) also plans to transport sewage sludge across Scotland from Glasgow’s Shieldhall and Daldowie sewage treatment plants to be burnt at the same power station.

FoES and SWT believe that both these schemes contradict the European urban waste water treatment directive (1991).

The directive states that “sludge arising from waste water treatment shall be re-used, whenever appropriate” and that “disposal routes shall minimise the adverse effects on the environment”. According to the groups, incinerating sludge in a power station does not qualify as re-use.

EoSW claims that its sewage sludge strategy is balanced and diverse, and that a variety of routes for the sludge it produces are being developed, including re-use on agricultural land.

Bryan Wallis, regulation and compliance manager with EoSW said: “We plan to adopt co-combustion of sludge with coal at Longannet power station, as part of the £50M Levenmouth (PFI) waste water project. This represents less than 20% of the sludge we produce in our area. Combustion of sludge at power stations offers several advantages – energy is recovered for electricity production and there is a reduction in the need to use non-renewable fossil fuels such as coal.”

Depending on the outcome of the complaint against EoSW, a formal complaint may also be made to the EC over the WoSW scheme in Glasgow.

Action inspires action. Stay ahead of the curve with sustainability and energy newsletters from edie