Maendy Quarry is an abandoned stone quarry near

Cardiff Cardiff (; cy, Caerdydd ) is the capital and largest city of Wales. It forms a principal area, officially known as the City and County of Cardiff ( cy, Dinas a Sir Caerdydd, links=no), and the city is the eleventh-largest in the United Kingd ...

South Wales South Wales ( cy, De Cymru) is a loosely defined region of Wales bordered by England to the east and mid Wales to the north. Generally considered to include the historic counties of Glamorgan and Monmouthshire, south Wales extends westwards ...

that was subsequently used in the 1960s as a landfill site for industrial waste. The site became infamous in the early 1970s when it became clear that toxic industrial waste had been deposited at the site, which included

PCB PCB may refer to: Science and technology * Polychlorinated biphenyl, an organic chlorine compound, now recognized as an environmental toxin and classified as a persistent organic pollutant * Printed circuit board, a board used in electronics * ...

s from Monsanto Newport factory now owned by Eastman. In addition, local farmers had been paid compensation for the death of animals that had been grazing near the site. The company using this disposal site also used the nearby

Brofiscin Quarry Brofiscin Quarry, Groes Faen is a disused limestone quarry in Groes-faen, near Llantrisant in South Wales. It was used for about seven years for the dumping of toxic waste including polychlorinated biphenyls (PCBs) and was capped in 2011. Some 72 0 ...

. The Brofiscin site is the main touchpoint when discussing the pollutants that ended up in these quarries. The site which is on the watershed between the

River Ely The River Ely ( cy, Afon Elái) is in South Wales flowing generally southeast, from Tonyrefail to Cardiff. The river is about long. The Ely's numerous sources lie in the mountains to the south of Tonypandy, near the town of Tonyrefail, ris ...

and

River Taff The River Taff ( cy, Afon Taf) is a river in Wales. It rises as two rivers in the Brecon Beacons; the Taf Fechan (''little Taff'') and the Taf Fawr (''great Taff'') before becoming one just north of Merthyr Tydfil. Its confluence with the R ...

continues to produce a polluting leachate and requests to the local authority to provide information about the material contained in the site have been refused. Effects of Toxic Waste - freedom of information request to Rhondda Cynon Borough Council
/ref>

References

Landfills in the United Kingdom {{Wales-geo-stub