Residents living near the controversial Withyhedge landfill site have dismissed a claim from its operator that foul smells have now been dealt with.

In an update on the long-running row, Dauson Environmental Group said it was “confident that the issue of odour has been resolved”.

Colin Barnett of the Stop the Stink campaign said the community continued to report problems “every day”.

Wales’ environment watchdog Natural Resources Wales (NRW) said the situation at Withyhedge was “completely unacceptable” and its priority was to “compel the operator to address source of emissions and odours from the site”.

Residents have been reporting concerns to NRW about the site near Haverfordwest, Pembrokeshire since October 2023, describing it as like “a stink bomb on steroids”.

The regulator has served two enforcement notices, with the latest giving the landfill’s operator until 14 May to address the issues.

Mr Barnett said more than 40 days had passed since that deadline and the community was still “suffering”, with the smell impacting people’s mental health and exacerbating underlying health conditions like asthma.

He acknowledged there were days where it was “maybe” not as bad as it had been but said “that smell should not be coming past the [landfill’s] border”.

“This has been happening for 10 months and several times they’ve assured us it will stop – they’ve failed and failed and failed,” he said, calling for an inquiry into NRW’s handling of the row.

Last week, a report by Public Health Wales revealed levels of hydrogen sulphide in the air near the site during March and April which exceeded World Health Organisation (WHO) guidelines for odour nuisance.

It can result in a strong, “eggy” smell and the organisation reiterated advice to residents to close windows and doors “when nasty smells occur” and seek medical advice if they felt unwell.

Claire Holman, president of the Institute for Air Quality Management said the findings reinforced “that there is a real problem” and that the “regulator needs to get their act together”.

Issues with odour “can go on for years in some landfills and traditionally the regulators are very slow to respond,” she warned.

Monitoring and remediation work “takes time” – “I don’t think there are going to be any quick fixes to this”, she added.

A spokesperson for Dauson Environmental Group said the firm had implemented measures in consultation with NRW “to ensure that any odour from the site is minimised and does not affect the surrounding community”.

“We once again apologise for the impact this had had on local residents and our community,” they said, adding that the company had invested over £5m in improving the site since taking it over in 2022.

Responding to allegations made in a recent Channel 4 Dispatches programme, the spokesperson said that the firm “does not knowingly accept non-conforming waste” – including plasterboard, which can produce hydrogen sulphide gas as it breaks down.

BBC Wales has spoken to one of the former employees featured in the programme, who raised questions over the way leachate – polluted liquid which drains from the landfill – was handled.

Tractor driver Andrew Phillips said the site “could not keep up with the leachate” and he had been instructed to respray it on the waste, or “pour it into massive holes” that had been dug at the site.

“I should imagine it evaporates and causes more of a smell,” he said.

“The people of Haverfordwest and Spittle deserve to know the truth of what’s happening there.”

Dauson Environmental Group said the site’s leachate was “managed in strict accordance with our leachate management plan.”

“We should make clear that the re-circulation of leachate is an accepted practice and not a violation of our permit.”

“In addition, in excess of 35,000 tonnes of leachate has been removed from site in the past 12 months for treatment.”

Dauson Environmental Group’s director, David Neal has been at the centre of a row involving a £200,000 donation from his company to the leadership campaign of First Minister Vaughan Gething.

Mr Neal was given a suspended prison sentence in 2013 for illegally dumping waste on a conservation site and four years later he was prosecuted again for not removing it.

A spokeswoman for NRW said its priority has always been to compel the site’s operator “to address sources of fugitive emissions and odours from the site”.

“This regulatory activity is separate to ongoing investigations, which may lead to criminal sanctions.

“The level of regulatory scrutiny NRW has applied to Withyhedge in response to the offsite odour issues has been significant.”

She added that NRW had a regular presence at Withyhedge since the increase in odour complaints started in late October 2023 and it was still receiving daily odour reports from residents and continued to undertake “odour assessments”.