TCD Avoca Mines/River Publications

Several people have asked for a list of the Internal Reports that we have published on the Avova Mines and its impact on the Avoca River.  These were done mainly in the 1990's with more recent research published in journals.  There is also significant work availble in thesis format.  Below is a list of the internal reports that are available.  There are two reports which were Governmnet Reports that are confidential and so are not included both dealing with plans to rehabilitate the mines.

• Sullivan, M. and Gray, N.F. (1992) An evaluation of the fisheries potential of the Avoca catchment. Technical Report 9, Water Technology Research, Dublin, 47pp.
• Gray, N.F. (1995) Flow calculation in the River Avoca: flow calculation and flow data. Technical Report: 10, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-11-8) Revised July, 1995.
• Gray, N.F. and Doyle, T.M. (1995) Characterisation of acid mine drainage generating sites. Technical Report: 11, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-12-6)
• Gray, N.F. (1995) Water quality of the surface waters at Avoca Mines and the Avoca River: Intensive sampling period May to October, 1994 (Interim report). Technical Report: 12, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-13-4)
• Gray, N.F. (1995) Main adit flow and metal discharge rates. Technical Report: 13, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-14-2)
• Gray, N.F. (1995) Field assessment of acid mine drainage contamination in surface waters. Technical Report: 14, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-15-0)
• Kilroy, A. and Gray, N.F. (1994) A review of treatability, toxicity and biodegradability test methods. Technical Report: 15, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-16-9)
• Gray, N.F. (1995) Influence of secondary sulphate mineral formation on the impact of acid mine drainage to surface waters. Technical Report: 16, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-17-7)
• Byrne, C. and Gray, N.F. (1995 ) Environmental impact of acid mine drainage on the Avoca River: Effects of habitat types on biological monitoring of the macro invertebrate fauna. Technical Report: 17, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-18-5
• Byrne, C. and Gray, N.F. (1995) Environmental impact of acid mine drainage on the Avoca River: Acute toxicity experiments in the field using macro invertebrates. Technical Report: 18, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-19-3)
• Herr, C. and Gray, N.F. (1995) Environmental impact of acid mine drainage on the Avoca River: Metal fluxes in water and sediment. Part I Introduction to metal accumulation in riverine sediments. Technical Report: 19, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-20-7).
• Herr, C. and Gray, N.F. (1995) Environmental impact of acid mine drainage on the Avoca River: Metal fluxes in water and sediment. Part II Metal contamination of riverine sediments. Technical Report: 20, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-21-5).
• Herr, C. and Gray, N.F. (1995) Environmental impact of acid mine drainage on the Avoca River: Metal fluxes in water and sediment. Part III Metals in water and suspended particulate matter.Technical Report: 21, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-22-3).
• Gray, N.F. (1995) An objective index for the assessment of the contamination of surface and ground waters by acid mine drainage. Technical Report: 22, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-23-1)
• Gray, N.F. (1995) A substrate classification index for the visual assessment of the impact of acid mine drainage in lotic systems. Technical Report: 24, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-25-8)
• Doyle, T.M. and Gray, N.F. (1995) Protocol for monitoring and predicting the impact of acid mine drainage: Designing and setting up a geographical information system (GIS). Technical Report: 25, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-26-6
• Sullivan, M., Gray, N.F. and O'Neill, C. (1995) Synoptic overview of the Avoca-Avonmore catchment and the Avoca Mines. Technical Report: 26, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-27-4)
• Gray, N.F. and Sullivan, M. (1995) The environmental Impact of acid mine drainage. Technical Report: 27, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-28-2)
• Herr, C. and Gray, N.F. (1995) Protocol for monitoring and predicting the impact of acid mine drainage: sediment sampling. Technical Report: 28, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-29-0) 
• Gray, N.F. (1995) Procedure for the estimation of the impact of acid mine drainage to surface waters. Technical Report: 29, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-30-4)
• O'Neill, C., Herr C. and Gray, N.F. (1995) A survey of soil and vegetation in the area surrounding the East Avoca Mine, Co. Wicklow. Technical Report: 31, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-32-0)
• Gray, N.F. (1995) Biorehabilitation of the acid mine drainage phenomenon by accelerated bioleaching of mine waste: Executive summary of the work done at Trinity College, Dublin. Technical Report: 33, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-34-7).
• Herr, C. and Gray, N.F. (1995) Seasonal variation of metal contamination in riverine sediments of the Avoca River with regard to seasonal differences. Technical Report: 34, Water Technology Research, Trinity College, University of Dublin, Dublin. (ISBN 1-872220-35-5).

Video of the River Avoca in Flood

View of the January flood on the River Avoca from the bridge in the village

Undergraduate visit to the River Avoca and the mines

The new Junior Sophister (third year) students in Environmental Science and Botany explored the abandoned Cu-S mines just outside Avoca.

They experienced at first hand the historical importance of the site as well as the environmental damage that the site causes.

In the afternoon they had a brief look at the impact acid mine drainage is having on the river.  Macro-invertebrate sampling revealed that it supports a wide range of species at Avoca Bridge just 2.4 km downstream of the mines, confirming that the river has recovered significantly since the 1990’s due to the reduction in the strength of the metals being discharged from the mine drainage.

Avoca mines: Sunday Times

Once again the problem of Avoca mines has hit the newspapers with renewed demands for immediate, yet conflicting, action to be taken.

In my opinion the problem of rehabilitating the abandoned Cu-Pb mining site at Avoca has become much more complex than when we first put forward our own rehabilitation plan in 1995 after our intensive five year study that has been the basis of all the subsequent work done on the site. My main concern is that the movement of water through the mine workings may significantly alter due to ochre deposition and lead to acid mine drainage (AMD) being discharged into surrounding sub-catchments. This has already been seen in the changing pattern of discharge rates from some of the minor adits. Also, that any physical work done on the site may also cause problems both in terms of AMD generation as well as altering the current flow pattern.

Our own studies have indicated that the river has shown significant recovery since closure, although the rate of recovery has flattened out since 2006. The closure of the fertilizer factory, which had been shown in our studies in the early 1990’s to be the major limiting factor for salmonid migration into the catchment due to ammonia toxicity, has meant that salmon have been present for many years. However, the damage to the habitat diversity of the river, mainly from ferric hydroxide precipitation, has left it relatively impoverished in terms of other species. So where do we go now? My firm belief is that we should largely wait and see. The action of surface water on Mount Platt has to be controlled, that has been obvious for two decades and is a relatively simple and cheap thing to do. But as the article in today’s Sunday Times points out a balance has to be struck between preserving the mining and environmental heritage of the site as well as reducing the impact on the river.

Theresa Hughes of the Water Technology Research Group has been looking at an alternative treatment for the acid mine drainage coming from the Avoca site that may provide a sustainable treatment solution. She has been working on the co-treatment of AMD with domestic wastewater which means that treatment is done at a central treatment facility that will be monitored and maintained 24/7, unlike many on-site systems used at abandoned mines. The problem is that the AMD has to be treated to a very high level forever, and this is best achieved using more conventional treatment technology. What is interesting is that neither Avoca nor Arklow have proper domestic wastewaetr treatment systems in place at this time offering the potential to invest both the capital and operating costs from the treatment of Avoca mines in a new permanent co-treatment facility. More details of Theresa’s work can be seen via the link.

River sampling can be very unpredictable

River sampling can be very unpredictable especially in hard rock (e.g. granite) catchments. The River Avoca is very flashy with a discharge rate that can increase from 0.7 m3/s to 70 m3/s within just a few hours during intense rainfall events. Yesterday the height of the River was 1.6 m lower than this afternoon after 18 hours of heavy showers. The picture shows a slightly worse event in January 2010 which resulted in localized flooding. On that occassion the water was 2.2m higher than normal at the same point. Sampling is normally planned many weeks or months in advance but when conditions are like this then it is impossible and dangerous to proceed.  So if at all possible always work in soft rock catchments (e.g. chalk) where discharge rates are largely unaffected by rainfall events. No sampling tomorrow!

New research on acid mine drainage

Lisa Egan has joined the Water Technology Research Group to work on using duckweed to assess the impact of acid mine drainage and for its potential treatment. Link to Lisa's research page.