An electrostatic induction system includes used activated carbon as electron-collecting units, to which electrons are supplied by an electrostatic induction apparatus so that impurities that have been absorbed by activated carbon are neutralized or reduced, and neutralized or reduced used activated carbon is acquired. The neutralized or reduced used activated carbon is buried in an environmental conservation implementation area in such a manner that an amount of the buried neutralized or reduced used activated carbon and a number of locations at which the neutralized or reduced used activated carbon are buried are adjusted depending on a property of the environmental conservation implementation area, and that the buried neutralized or reduced used activated carbon gradually decrease an earthing resistance of the environmental conservation implementation area so as to cause the earthing resistance to have a value less than or equal to 10Ω.