A search and rescue expert called to a St Ives car park where a mineshaft opened up on Saturday afternoon says 'Cornwall is riddled with thousands of holes'.

Emergency services were called after the massive hole appeared in Garth-An-Creet on Saturday evening and now more background has emerged on the mineshaft.

A post by Stuart Dann from Mining Eye on the Carbis Bay Crew Facebook page, run by a group of cavers, mine explorers, divers and climbers, has shed more light on the fascinating history of what came before the housing estate where the drama took place on Saturday.

It read: "It appears that prior to the construction of the estate, an inadequate mining investigation was done to locate and subsequently make safe the various things that can open up and fill us with wonder. Looking at the record, they did have the decency to put a car park over the shaft site, rather than a house."

Emergency workers and volunteers at the scene
Emergency workers and volunteers at the scene

The post continued: "What's happened is that the choke, or timbering covering the shaft (approx 200m deep) has failed and the bedrock (about 3.5m down-ish) has 'coned' out under the tarmac to form quite an exciting hole. This was apparently 20m deep or so, but when measured was 10m. The shaft is about 8ft square (sorry to mix units) and a fair bit bigger at the just-under-the surface."

The crew's post went on to say that the hole appeared to be what was known as the Cornish Shaft of the St Ives Consols Mine - one of the biggest in the area - and, since there were others nearby, it was possible that more could open up.

According to the database at Cornwall in Focus, the mine is thought to date from about 1818 and is said to have produced more than £1million worth of copper ore and black tin between 1818 and 1873.

The database said that the early development of St Ives Consols was largely overseen by Captain Hodge, a colleague of Richard Trevithick.

The Mines of Cornwall, a book published in 1864 by Thomas Spargo, said that in 1865 the mine employed 218 men, 59 mine girls and 104 boys.

The book said that St Ives Consols was equipped with a 50-inch pumping engine, 30-inch pumping engine, a 26-inch stamps engine with 52 heads, two winding engines (20-inch and an 18-inch) and five water stamping mills, each with 36 heads.

The hole opened up at around 4pm on Saturday, although it is thought that the asphalt has been dropping for several weeks.

Police were called to the scene, along with emergency workers from Cormac and a volunteer team from Cornwall Search and Rescue to assess the hole.

Jim Gallienne, from Cornwall Search and Rescue said they arrived on site at around 7.30pm with a mine specialist to look into the hole.

He said: "It's a big hole. It's deceptive. The opening is only a metre or metre and half across. The tarmac on the surface is floating and there's a mineshaft underneath that drops about 40ft.

"A lot of the mine workings that we find ourselves working with are between 100 and 150 years old and it doesn't take a lot of changes in the way the water is permeating through the ground or a heavy lorry or something to open it up.

"This shaft was particularly close to the surface so it's fallen through.

"Our job was to make an initial assessment of it and make sure there weren't any houses or anything else at risk of falling in.

The hole that's opened up in a car park in St Ives
The hole that opened up in a car park in St Ives

"We've rigged up a safety line and assessed the edge of the opening to get an idea of whether there's tunnels leading off it. We've got a mining engineer who specialises in surveying mines and mine workings. He's made an assessment of it.

"A bit more tarmac will probably fall through but there's nothing there at the moment which gives us any cause to think other houses may be at risk but where there's one mine shaft there's often others.

"Cormac are there and they're putting in a cordon around it and a couple of fences around the immediate hole and in a wider area to make sure the public are safe and it will be up to someone to claim it and get it repaired.

Garth-An-Creet is marked by the red pin

"From a safety perspective it's quite useful to show people the hole doesn't go anywhere. We're more than happy to tell people what it is and it's nothing.

"We don't normally get called out to jobs like this but because there was a public safety element they wanted someone to assess whether the wider public were at risk.

"The callouts for us are very very rare indeed but Cornwall is riddled with thousands of holes so it does happen all the time but not always in such close proximity to houses."

The hole that's opened up in St Ives
The hole that opened up in St Ives

Local resident Clive Oxley was on the scene when the volunteers arrived.

He said: "The whole car park has been cordoned off and there's Cormac workers and police and mines rescue people everywhere. It's definitely a mineshaft."