it's known as the 'Blue Lagoon', but the flooded former quarry near Buxton hides a toxic secret.
It's so polluted that it's almost as toxic as bleach.
There are warning signs that state the water can cause skin and eye irritations and stomach problems, but people continue to swim there.
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Remaining largely cloudy with patchy drizzle over hills. Becoming milder, breezy with some brighter breaks in the west on Friday
Saturday looks like the best day of the weekend. Mainly dry for both Saturday and Sunday but a cooler, cloudier finish
Another largely cloudy and murky day. Perhaps a little brighter and feeling milder for Friday