摘要 |
<p>Uncontrolled discharge of metallic degradation products into the environment is prevented by using a bullet backstop (1) for a shooting range. Prevention of uncontrolled discharge of metallic degradation products into the environment involves using a bullet backstop for a shooting range. The bullet backstop comprises inclined parallel material layers (3, 4) including a watertight bottom layer that conducts percolating leachate to an intercepting device located beneath the bullet backstop, e.g. a drainage pipe (5) emerging in a container (10), and a projectile-stopping layer, e.g. sand located above the bottom layer where the projectile-stopping layer is of thickness to intercept shot projectiles. The metal-ion-enriched rainwater collected in the projectile-stopping layer has been provided with pH-neutralizing material and is in direct contact with the atmosphere, is able in the form of leachate to percolate into an underlying water-permeable layer of gravel or crushed stone material of coarse fraction, mixed with pH-neutralizing material, e.g. crushed limestone so that pH-neutralized leachate is able to run off via the watertight bottom layer and the intercepting device. The pH-value of the leachate in the intercepting device is checked at least intermittently by means of a measuring member.</p> |