CALLS have been made for a public inquiry into reports toxic waste dumped at a Gwent quarry is leaking into the surrounding area.

The Ty Llwyd Quarry in Ynysddu is believed to contain highly carcinogenic PCBs and other pollutants, which were dumped at the site decades ago by chemical company Monsanto from its Newport factory.

Manufacturing of PCBs, which were widely used in electric equipment, was banned in the UK in 1981 after tests revealed them to be deadly to humans and wildlife.

Recently, nearby residents came forward with claims that after heavy rain a potent-smelling brown foamy liquid flows from the site down through woodland and past homes.

South Wales Argus: Liquid flowing out of the Ty Llwyd Quarry in the Welsh village of Ynysddu, near Caerphilly. The landfill site may be leaking toxic chemical waste through a forest where children play, local residents believe.Liquid flowing out of the Ty Llwyd Quarry in the Welsh village of Ynysddu, near Caerphilly. The landfill site may be leaking toxic chemical waste through a forest where children play, local residents believe. (Image: PA)

Natasha Asghar, who represents the South Wales East region in the Senedd, said there were ongoing concerns about the safety of the site.

"Caerphilly County Borough Council is now the owner of the site, having compulsorily purchased the quarry, but has refused to register Ty Llwyd as contaminated land in spite of local concern about leachate leaking out and polluting neighbourhood properties as well as the roads," she said.

"Natural Resources Wales (NRW) confirms it is solely the council's responsibility to register contaminated land, but [the council] maintains that the leachate does not flow from its property."

South Wales Argus: Natasha Asghar speaking in the Senedd.Natasha Asghar speaking in the Senedd. (Image: senedd.tv)

Conservative Ms Asghar has now called on the Welsh Government to investigate, and called on ministers to "join me in supporting the residents... and local councillors Jan Jones and Janine Reed, in calling for a public inquiry to be held into the potential threat to neighbouring land and the River Sirhowy from the leaking of harmful substances from Ty Llwyd quarry".

In response, Senedd trefnydd (house leader) Lesley Griffiths said: "Public Health Wales have been fully engaged with Caerphilly council and are content with the measures currently being employed to minimise any human health risks.

"I know NRW are also working with the local authority and their contractors to provide some technical assistance and advice regarding further works that may be required to minimise off-site impacts caused by site drainage during peak rainfall events."

The council has previously claimed the liquid found near the quarry site is “normal surface water”, but has urged people to stay away from the quarry and surrounding area during periods of heavy rainfall.

Last May the council had a drainage system installed which it said was designed to keep surface run-off separate from any contaminated liquid, also known as leachate.