This group of 26 former producing mines, last operated in the 1800s, were described in 1929 by the mining commentator Hamilton Jenkin as “the richest in tin of all the Cornish mines, probably the richest tin mine which has ever been worked in the world”.
Historic production grades were very high, averaging approx 3% tin, and peaking at over 5.5% tin. Even assuming a current production grade of only 2% tin this would be one of the top 3 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 program.
This will be a six month program of 33 diamond drill holes from 26 drill sites. Cornwall Council (Mineral Planning Authority) granted consent on July 19.
Local residents had raised concerns that the opening of a mine would bring air, noise and light pollution; increased heavy traffic, underground stability, water table issues, damage to wildlife and many other impacts that would be inevitable.
But the company says no pneumatic or percussive drilling is planned, and no blasting is involved.
It says 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, the 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 very low levels of noise from the drill rigs and no drilling will take place within 50 metres of residences.
The company says 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.
CEO Sally 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 program 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.
The drill rigs will 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.
Sally Norcross-Webb said “Although the planned drilling program 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 program. I am pleased that this is now a condition.”