INTERNATIONAL PARTNERSHIP ADDRESSING HERITAGE POTENTIAL AND REMEDIATION OF MINE DRAINAGE IMPACTS ON THE RIVER AVOCA (IRELAND) AND AT AMLWCH (WALES) A. Doyle 1 , P. O’Connor 2 , D. Harrington 3 , W. Roche 4 and N. Johnstone 5 1 Institute for Research on Environment and Sustainability, University of Newcastle, UK 2 Geological Survey of Ireland, Dublin, Ireland 3 Wicklow County Council, Ireland 4 Central Fisheries Board, Ireland 5 Menter Môn Development Agency, Anglesey, Wales, UK Abstract The authors consider approaches to environmental remediation of the abandoned copper mines at Avoca in Ireland and at Amlwch in Wales, UK in terms of balancing the interests of various stakeholder groups. Water and water quality are essentially heritage concerns. The legacy of mining at Avoca creates the most significant river pollution in Ireland. The problems of Avoca have been considered in their various aspects at different times, generating copious data from various fields of interest. This ‘heritage’ is currently being explored by scientists from different disciplines through The Celtic Copper Heritage (CCH) initiative which has obtained funding under the EU INTERREG 111A Programme. Heritage and remediation potential is also afforded by combining international understanding with approaches to a similar ore body in Wales which has been worked for the same minerals over history. The similarity of the two places extends to the fact of their both being worked by the same company, owners, miners and mining engineers. The mine sites at Amlwch are included in the International Commission on Monuments and Sites’ Register of Landscapes of Outstanding Historic Importance in Wales. The surviving mining heritage has close parallels with that of Avoca. Many studies have been made of both places and their mining impacts. Recently, in Avoca, a pilot water treatment operation was commissioned by the CCH project to quantify process material and costs. A conclusive study for the remediation of the mine water which will include recommendations for the mine sites is soon to be commissioned by the Department of Communications Marine and Natural Resources (DCMNR). Local heritage issues will feature in this. Actions to treat the mine water discharges will needs to consider a number of variables, including the characteristics and disposal of the residual products of the proposed treatment process. Introduction “Water is not a commercial product like any other but, rather, a heritage which must be protected, defended and treated as such” (WFD 2000). The whole of The Avoca catchment is rich in economic minerals, and their economic importance has been understood for centuries. Kinahan (1889, p.109) noted that across Wicklow “mining operations have been in varying activity at intervals from time immemorial”. Different forms of mining at different times have played a major role in the economy of Avoca and Amlwch and their surrounding districts. Consideration of various aspects of heritage likewise has potentially important economic benefits for their future. Mining took place in an era when there were few environmental controls in place, and significant environmental degradation has occurred at both locations. Gallagher et al. (1998) reported on the river’s historical sink use, and widespread contamination of the mine site and surrounding land surface by spoil and serious pollution of the Avoca River by acid mine drainage that has long been recognised as a major problem (Flynn, 1994; O’Suilleabhain, 1996; O’Suilleabhain et al., 1997; Gallagher and O’Connor, 1999; Wright et al., 1999). The river is severely impacted by mine drainage and is considered by the EPA to be the most severely polluted stretch of river in Ireland. Lucey (2005) noted for EPA on fish kills, indicating “catastrophic ecosystem disruption” that the unacceptably high rate of mortality in 2003 was inflated by recurring deaths of fish in the Avoca as a consequence of discharges from the copper mines. The stock of salmonid migratory species that existed in abundance before industrial scale mining in the eighteenth century has degenerated to a stock of less than two per cent. Forty three per cent of all fish kills recorded nationally in 2003 occurred in the River Avoca. EPA National Water Quality Reports since 1970 (at 3 year intervals) consistently identified biotic indices of 0 along this stretch of the river, and elevated concentrations of heavy metals are present in the sediments as well as the water column. Remediation studies will need to consider benthic substrate as well as the loadings in solution in the water column. A nitrogenous fertiliser factory operated between 1964 and 2002 downstream of the Avoca mines discharging significant waste with a high ammonia concentration adding to the problem of heavy metals. IMWA Symposium 2007: Water in Mining Environments, R. Cidu & F. Frau (Eds), 27th - 31st May 2007, Cagliari, Italy