ENVIRONMENTAL-IMPACT AND REMEDIATION OF ACID-MINE DRAINAGE - A MANAGEMENT PROBLEM

Work carried out at the abandoned copper (Cu) and sulphur (S) mine at Avoca (south east Ireland) has shown acid mine drainage (AMD) to be a multi-factor pollutant. It affects aquatic ecosystems by a number of d irect and indirect pathways. Major impact areas are rivers, lakes, est uaries and coastal waters, although AMD affects different aquatic ecos ystems in different ways. Due to its complexity, the impact of AMD is difficult to quantify and predict, especially in riverine systems. Pol lutional effects of AMD are complex but can be categorized as (a) meta l toxicity, (b) sedimentation processes, (c) acidity, and (d) saliniza tion. Remediation of such impacts requires a systems management approa ch which is outlined. A number of working procedures which have been d eveloped to characterise AMD sites, to produce surface water quality m anagement plans, and to remediate mine sites and AMD are all discussed .