Treating contaminated ground - by modifying air and water brought to surface by vertical shafts

摘要

Area (3) of contaminated ground, e.g. forming pt. of an old waste-tip, and normally superimposed on a water-laden lower area (4), has shafts (1,2) sunk vertically. Air is extracted via the apertured shaft walls and pumped to the surface. Here one of the parameters, esp. O2 content and moisture, which affect aerobic or anaerobic biological breakdown of contaminants, are measured. After pref. modification, e.g. by admixture with fresh air or O2, the extracted air is returned to the lower levels. The air monitoring circuit may be augmented by a similarly operated circuit for the lower water-bearing station. To reduce opt. localised pollution, the treated area may be covered by permeable sheeting. Circulated water may undergo pH adjustment and be supplied with nutrients. ADVANTAGE - Purifier is effected in situ without transporting or moving affected ground.