Its water has a very high pH, that is, it is very alkaline, owing to the presence of caustic chemicals that are leaching from the waste left from the lime burning.

Large volumes of solid waste from the lime burning were dumped in tips nearby, creating spoil heaps contaminated with traces of quicklime and with ash from the coal used in the process.

[1][4][3] After the war the site was occupied by an RAF unexploded ordnance disposal unit, known as an X station, and used for storage and disarmament of captured German chemical weapons and V-rocket warheads.

The RAF disposed of chemical weapons, including mustard gas and phosgene, by burning the substances with bleach on the surrounding hills.

[6] Signs at the site state the water can cause "skin and eye irritations, stomach problems and fungal infections such as thrush" and that the quarry is known to contain car wrecks, dead animals, excrement and rubbish.

[5] In order to deter swimmers the water was dyed black in 2013 by High Peak Borough Council, who acted after being unable to get in touch with the site's owner.

[5] In March 2020 the lake was dyed again following reports of people gathering there despite social distancing instructions issued by the British government to combat the COVID-19 pandemic.

[9] It was redyed by High Peak Borough Council and Derbyshire Fire and Rescue on 29 May after people flocked to the site for the bank holiday weekend (25 May).

[10] With people continuing to visit the site local farmers attempted to deter them by spreading pig and cow slurry across the surrounding land on 19 June 2020.