Old mines can have new uses.
For centuries it has been known that mining produces a range of harmful side-effects—and that they can be ameliorated. The first European textbook on mines and quarries, written by Georgius Agricola in 1550, considered the case against mineral extraction and concluded:
The strongest argument of the detractors is that the fields are devastated by mining operations, for which reason formerly Italians were warned by law that no one should dig the earth for metals and so injure their very fertile fields, their vineyards, and their olive groves … And when the woods and groves are felled, then are exterminated the beasts and birds, very many of which furnish a pleasant and agreeable food for man. Further, when the ores are washed, the water which has been used poisons the brooks and streams, and either destroys the fish or drives them away… Thus it is said, it is clear to all that there is greater detriment from mining than the value of the metals which the mining produces. (Agricola 1912:8)
While mining continues, the environmental side-effects are wholly undesirable. But when working has ceased, beneficial side effects arise. Agricola knew this:
Moreover, as the miners dig almost exclusively in mountains otherwise unproductive, and in valleys invested in gloom, they do either slight damage to the fields or none at all. Lastly, where woods and glades are cut down, they may be sown with grain after they have been cleared from the roots of shrubs and trees. These new fields soon produce rich crops, so that they repair the losses which the inhabitants suffer from increased cost of timber, (ibid.: 14)
Agricola’s book was translated from Latin by Hoover while he was president of America. There are three crucial points: