The boss of a bioplant says he is frustrated by a fire which damaged a roof that prevents odour from the waste process being emitted.
A blaze broke out at the Rothwell Lodge Farm site of Fernbrook Bio just five days before Christmas.
Organic waste is converted into energy in its anaerobic digester.
The fire started while a separate technology supplier was carrying out work there, and the result was significant damage to a contraption which stops pungent smells annoying people who live nearby.
And Fernbrook Bio managing director Shaun Cherry has warned it will not be fixed for up to six more weeks.
Mr Cherry has apologised, saying the firm was particularly frustrated because the fire took place just a month after the installation of the latest set of anti-odour measures had been completed.
He added: “It’s not a requirement to cover the end storage tank, but it is best practice for all concerned which we’ve always done and will continue to do so.
“Fernbrook Bio do care about our neighbours and have spent hundreds of thousands on odour improvements.
“Fernbrook Bio strive to be a good neighbour, we accommodate the local schools and provide a site tour upon which they base their waste recycling projects.
“This latest incident is just sheer bad luck for Fernbrook Bio.
“We apologise for all inconvenience caused and are working with the German suppliers to resolve this and fit the replacement roof as soon as possible.”
Readers have contacted the Northants Telegraph to complain about the stench in recent days, but one of the campaigners against the odours said Rothwell had not been as badly blighted by foul smells recently as it had in the past.
Michael Jones said: “The current system they are using has drastically reduced the levels of smell.”
And he added: “The whole principle is good, you can’t argue with it – it’s better than landfill.
“But it needs to be done correctly.”
The protest group has also said it is concerned smells in Rothwell could become increasingly frequent once waste is brought in from outside the county as well as from Northamptonshire itself.
People in the town and elsewhere are urged to report bad smells every time they notice them by calling the Environment Agency on freephone 0800 807060.