Premise: Brofiscin Quarry, Groes Faen is a disused limestone quarry in Groes-faen, near Llantrisant in South Wales. It has been designated a Site of Special Scientific Interest due to the exposed Early Carboniferous geological formations on the site. It was used for about seven years for dumping of toxic waste including PCBs and was capped in 2011.
Hypothesis: Brofiscin Quarry is the 9th largest quarry of its kind in the UK.