The picture above is of a local massive bomb crater dating from WW2. The area was targeted by enemy aircraft as the local limestone quarry was essential in the fluxing and refractory process when making steel.
The local water that springs from the ground is very rich in minerals as the aquifer below is dissolved by the annual 40" - 50" of precipitation that is acidified by the absorption of carbon dioxide from the atmosphere.
In 1948 Bellan Brook was lowered by 6 feet at its upper reaches below Ty Draw and dredged all the way down to Treflach pool with all ponds desilted between (a valuable fertilizer for the land). Since then parts have been partially piped that allows cattle to graze without contaminating the stream which eventually trickles through Sweeney Fen (a Site of Special Scientific Interest or SSSI).
Pictured below is limescale build up over 40 years in a pipe. Stones that rest on the stream floor are encrusted with lime that makes them an excellent habitat for wildlife to flourish. It is a known fact that the harder the water the lower the toxicity of other minerals and metals to aquatic life.
