Great Wheal Vor was once described as "the richest in tin of all the Cornish mines, probably the richest tin mine which has ever been worked in the world".
Work stopped at the group of 26 former mines near Breage in the late 1870s but permission has just been granted for a mineral exploration company to start exploratory digging.
Cornish Tin Limited is a Cornwall-based mineral exploration company which has rights to explore for and extract all minerals and aggregates including tin, lithium, copper, tungsten and geothermal energy on the site near Helston.
Historic production grades at Great Wheal Vor were very high, averaging approx 3 per cent tin, and peaking at over 5.5 per cent tin. Even assuming a current production grade of only 2 per cent tin this would be one of the top three tin mines by grade in the world if being mined today.
Cornish Tin has now been granted planning consent for its Phase 1 exploration drilling programme. This will be a six-month programme of 33 diamond drill holes from 26 drill sites.
Cornwall Council's Mineral Planning Authority granted consent on Monday, July 19.
There has been concern raised in the area by some residents, but Cornish Tin is promising that no pneumatic or percussive drilling is planned, and no blasting is involved.
Extensive work has been carried out by and on behalf of the company to ensure that the natural environment is protected, including adoption of all measures under an Ecological Impact Assessment by Cornish firm Plan for Ecology. Consent was applied for and has been granted under the Town and Country Planning (General Permitted Development ) (England) Order 2015.
Sally Norcross-Webb, CEO of Cornish Tin, said: “After five years of painstaking geological research, work on environmental protection and securing mineral rights, Cornish Tin now has the go-ahead to open up for exploration one of the most important mining areas in Europe.
"The mines closed in the 1870s, not through any lack of mineral resource, but due to 20 years of litigation against illegal operators who took what they could grab, before losing the case, but had to leave significant resources still in the ground. Since closure 150 years ago, no-one has been able to put together the necessary mineral rights to take the project forward, until now.”
Describing the Great Wheal Vor Project Area in 1963, the eminent geologist Jack Trounson wrote: “… when they were abandoned there was still a great amount of entirely unexplored ground in the very heart of the area and there were lodes known at surface on which little or nothing had been done in depth”.
Cornish Tin’s Phase 1 drilling is in areas directly safeguarded for mineral exploration and extraction by Cornwall Council’s Minerals Safeguarding Development Plan.
Key environmental protections include:
There will be very low levels of noise from the drill rigs (which are small and quiet), and no drilling will take place within 50 metres of residences. All drill sites without exception will be screened by straw bales or equivalent measures, which operate as further noise mitigation and present a more “agricultural” appearance.
Ms Norcross-Webb said: “We offered to commit to a maximum noise limit of 55 decibels, even though the applicable British Standard is 65 decibels, to demonstrate an acoustically sympathetic approach towards good neighbourly relations, and I am pleased that this is now a condition.”
The drilling programme will not affect Public Rights of Way, and operation of drill sites will be in strict compliance with Environmental legislation and Health and Safety legislation, to protect Public Safety.
There will be little impact on traffic conditions – when drill rigs move between sites, using access points agreed by Cornwall Council, this will be timed outside busy school run times, and personnel with high visibility clothing will be present to manage this safely.
Ecological protections include positioning drill holes to protect hedgerows, natural water features, wildlife (for example, two drill holes have been relocated from their original positions to be even further away from badger setts than the recommended limit), monitoring for the presence of any roosting bats, provision for invasive plant species surveys, habitat management plans, and water sampling and analysis at drill hole locations.
In the MPA (Cornwall Council) Officer Report it is stated that “the council’s ecologist notes that the Ecology Reports are very comprehensive and of high quality and confirms she is satisfied with the recommendations in the submitted report”.
Ms Norcross-Webb added: “Although the planned drilling programme of 33 holes will not involve the loss of any trees, we are committed to support the local natural environment and we offered to the local community at our cost 33 young trees of species native to Cornwall and supportive of wildlife, to be planted in the first tree-planting season following the completion of the drilling."
Cornish Tin hosted a Zoom meeting on July 7 to which all local residents and interested parties were invited, as well as Breage and Sithney parish councillors and Cornwall councillors.
In response to concerns that the company had not yet held a public meeting, Ms Norcross-Webb explained that Covid regulations has so far made this impracticable but that Cornish Tin had instead participated in Zoom meetings, circulated news updates and spoken and communicated by email and letter with local residents.
The company confirmed it would hold a public meeting prior to the start of drilling.
In a Cornwall Council officer report, councillor John Keeling, representing Porthleven, Breage and Germoe, said: “I think that every consideration has been given to the Great Wheal Vor Action Group and from what I heard on the last virtual meeting, explanations were given on how Cornish Tin would mitigate against any inconvenience caused by the exploratory drilling.”
Cornish Tin, which plans to achieve net zero carbon status, is hoping to be at the forefront of Cornwall's return to mining.
She said: "Cornwall is still one of the poorest regions in Europe, but with further investment in our minerals sector Cornwall could level up and retake its place as Europe’s leading tin producer. With Cornwall as a thriving hub of sustainably produced minerals, thousands of direct and indirect jobs would be created.
"The accepted ratio in the minerals sector is that for each one 'direct' job in the minerals industry, four 'indirect' jobs result, for example in the services, repair, engineering, transport, environmental and many other sectors, including as subcontractors or suppliers.
"Global demand for tin is fast outstripping supply. Tin is already listed as a critical resource by the US and China, and the tin price recently hit a ten-year high, with physical stocks globally at a 30-year low."
Ms Norcross-Webb added: “We have a once in a lifetime opportunity now for Cornwall, with its unique geological riches, to retake its place as Europe’s leading tin producer.”