This is a reader's letter published in the Hereford Times on October 24.

I refer to Phil Rowntree’s emotive letter (October 17) decrying the amended application for a proposed anaerobic digestion plant.

I am a civil engineer with a casual academic interest, but no commercial interest in the proposed anaerobic digestor.

I am also a citizen science volunteer monitoring nitrate and phosphate nutrient concentrations in the river Wye. It is widely assumed that elevated nutrients in the river result from upstream chicken farms and, more particularly, over-application of raw manure on farmland followed by run-off to the river after rain.

ALSO READ:

Given that a large number of chicken farms have been permitted in Herefordshire, planners are now obliged to consider mitigating proposals to deal with resulting chicken manure.

The removal of 100,000 tons per year of potentially-polluting waste for use as anaerobic digester feedstock to produce methane gas as an energy source while simultaneously limiting phosphate run-off in the river sounds like a good thing (granted the downside that methane and resulting carbon dioxide are greenhouse gases).

Often, the final by-product of anaerobic digestion is used as liquid fertiliser, which may defeat the object of manure collection. However, my enquiries indicate that this does not form part of the applicant’s proposal.

Instead, I understand a physical treatment process will remove phosphate from the digestate in crystalline form for commercial use elsewhere.

What are your thoughts?

You can send a letter to the editor to have your say by clicking here.

Letters should not exceed 250 words and local issues take precedence.

Moreover, the applicant proposes to treat liquid effluent from the bio-digesters biologically in gravel filters, reed beds and through recirculation and aeration in ponds before release of purified water to the river.

I assume that the thorny issue of vehicular traffic and associated carbon costs (plus the myriad other issues) have also been addressed in the application. Whether local community opinion is satisfied by technical argument remains to be seen.

I think local authority planners and Environment Agency should consider the application dispassionately on its scientific merits, statutory compliance and cost benefit balance rather than dismiss it on emotional, antitechnology, or political grounds.

GREGORY COHEN

Hay-on-Wye