This is the startling image of a vast lake that's formed in an old opencast site that has people very worried
![This is the startling image of a vast lake that's formed in an old opencast site that has people very worried](https://i2-prod.walesonline.co.uk/incoming/article28993878.ece/ALTERNATES/s615/0_WML_140424_Ffos_y_Fran_11JPG.jpg)
People fear it will contaminate local water supplies and be a magnet for young people and a drowning risk
People fear it will contaminate local water supplies and be a magnet for young people and a drowning risk