By Cleve Bryan

MAYS LANDING, N.J. (CBS) – Filled with bright teal water, former sand quarries are both beautiful and treacherous.

“The problem with sand quarries here in South Jersey is they drop off,” says Hamilton Township Dive Team Chief Glenn Hausmann.

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He was among the first responders called to a quarry near Thelma Avenue in Mays Landing for a drowning Monday night involving a 23-year-old man from Pleasantville.

Authorities say he slipped off a sand-bar and disappeared for hours.

Hausmann says the footing is completely unpredictable, “you could walk 5 feet or 25 feet and then suddenly you hit one of those craters and you just fall in.”

According to the New Jersey Division of Water Supply and Geoscience the state has nearly 900 active and abandoned surface quarries.

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Most quarries like the one near Thelma Avenue where Monday’s drowning occurred are private property.

Some are on public land like the one along Piney Hollow Road in Winslow Township.

You also can’t swim there, something police try to educate and enforce.

“If they’re back here as a family having a good time that’s fine, just the drinking is not allowed, the littering, and the swimming they can’t do,” says Winslow Twp. Police Lt. Chris Dubler.

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