The operator of a controversial Pembrokeshire landfill will only be able to accept waste onto a new part of the site after rigorous assessment it has been announced today.

Withyhedge Landfill near Haverfordwest has come under criticism since the end of last year with residents in nearby villages being plagued by a smell they described as like ‘a stink bomb on steroids’ causing them a raft of health problems.

In June Public Health Wales (PHW) said that at times during March and April 2024, levels of hydrogen sulphide, a colourless gas with an eggy smell, in the air around the site have been above the World Health Organization (WHO) odour annoyance guideline which could cause headaches, nausea, dizziness, watery eyes, stuffy nose, irritated throat, cough or wheeze, sleep problems and stress.

The site has been issued with enforcement notices by Natural resources Wales (NRW) and the site along company that manages it, Resources Management UK Ltd (RML), is still under investigation for possible environmental breach permits by NRW. When that process is completed NRW will determine if charges should be brought.

In May RML said that it would temporarily stop accepting waste but would continue to accept soil and clay materials as part of ongoing engineering works.

NRW says that it will undertake a thorough review of the site’s newly constructed cell 9, authorised by the current environmental permit, before any waste is allowed onto it.

The regulatory body will carry out a thorough review of a Construction Quality Assurance (CQA) validation report received from the RML, before giving the final approval to accept waste in the newly constructed cell.

The CQA report relates to Cell 9A - one of three sub-cells within Cell 9 which RML says is now ready to accept waste.

The submission of the CQA validation report is a critical requirement under the Environmental Permitting Regulations (EPR). It should provide the evidence to demonstrate that the base of the new landfill cell has been constructed and engineered in accordance with the approved design and specifications to prevent pollution of the land and groundwater underneath.

No waste disposal can begin in Cell 9A until NRW has reviewed the report, and confirmed it is satisfied that the construction was undertaken in accordance with the approved design and specification.

In addition to the engineering works for the new cells, NRW has also requested from RML updated procedures and plans covering the operation of Cell 9. The effective management of Cell 9 is fundamental to ensuring that activities at the landfill do not cause further odour problems. NRW will maintain a constant review of all the regulatory tools available to the organisation.

Caroline Drayton, Operations Manager for South West, NRW, said: “We realise there will be some public unease at the prospect of Withyhedge Landfill once again accepting waste, but I want to provide reassurance that, in addition to the rigorous assessment of the construction quality assurance for the new cell, we continue to focus on ensuring that the operator implements further improvements at Withyhedge Landfill to minimise the opportunity for any future emissions and off-site odours.”

The review of the CQA validation report will take several weeks. Upon completion, NRW will notify the site operator of its conclusion.

NRW said that it is maintaining its regulatory presence on site to ensure RML continues to drive the improvements needed to the gas management system, and to ensure they demonstrate that they are effectively managing the landfill gas from their operations.