- Environmental Rehabilitation
- ENVIRONMENTAL POLICY
- The Eldorado Gold Corporation & Thracean Gold Mining S.A. are committed to apply the strictest environmental standards so that natural resources are protected in every stage of the exploration, development, mining activities and environmental rehabilitation.
- The company will perform the necessary actions so that the Environmental impact of its activities is reduced, through the environmental training of its employees, the application of strict environmental inspections and the continuous environmental monitoring.
- The protection of the Environment in all project stages is important for the conservation of fauna, of the water and air quality and of the good health and safety of the employees and the local population.
- The company as well as external advisors will perform regular environmental inspections for the confirmation of compliance with the regulations.
- Existence of an adequate control and monitoring system of the MWMF.
- The effort of the employees to fully implement all of the environmental conditions is important and necessary for the economic success of the mine.
- Continuous Environmental protection, monitoring and management throughout all the stages of the Project.
- Fully meeting and even exceeding of all the terms and conditions regarding Environmental safety and Health security.
- Faithful implementation of the International Cyanide Management Code which has been developed by the Committee on Environment of the United Nations and by the International Council on Metals and the Environment.
- Use of the optimal available technology that is accepted by the EU, and in particular, of the method of INCO cyanide destruction (SO2 + air).
- Respect to the local cultural and historical Environment.
- The final land use shall be in accordance with the preservation of the local ecological characteristics and the applicable legislation.
- Environmental monitoring for five years after the closure of the project and the rehabilitation of the site
Tailings Management Ponds (TMP)
The ore residues after the leaching with a sodium cyanide solution in the presence of activated carbon for the extraction of gold and silver, are subjected to a cyanide destruction process with the INCOTM method (SO2+O2). After the application of the “INCΟ” method the total cyanide content of the above residue will be less than 1 ppm, which is at least ten times less than the specified threshold of the recent regulation of the European Union and of the Greek State as is mentioned in the mining activities waste management (EU Directive 2006/21/EU, Joint Ministerial Decision 39624/2209/Ε103). The residues of this process will be transported with trucks to the repository after their densification and dehumidification in filter presses.
The entire plan of the mine has been prepared according to the principle of zero discharge to the environment, in full compliance with the directive of the European Union on Best Available Techniques.
Filter Press unit
The filter press unit is a mechanical unit for the compression of the processed slurry after the phase of cyanide destruction. At the Perama plant a series of filter presses will be used in order to cover the daily quantity process needs.
Depending on the processing plant’s performance requirements as well as the required water quantity, a respective number of filter press units will be used, which will be connected in series.
Tailings impoundment site.
The main design features are:
- The facility will be delimited by four dykes (upstream, downstream, in the east and west), that will be constructed around the repository and will ensure the permanent and environmentally safe deposition of the residues of the production process.
- The main dyke (downstream of the site) will be a typical riprap dyke and for its construction, as for the rest of the dykes, material that comes from a borrowpit within the deposition area will be used.
- The design provides for resistance to a size 8.1 earthquake on the Richter scale.
- Its overall height will be 40 meters with final crest level at 195 meters above sea level.
- For the water management a water collection pond will be constructed downstream of the facility. The surface run-offs of the wider water catchment will be collected through a containment dyke in the northern part of the facility and through perimeter diversion channels.
The sealing of the tailings impoundment site is achieved with the covering of the bottom of the facility and of the sides of all dykes with a sealing compounds system, which shall include Geosynthetic Clay Liner (GCL) of very low permeability (1×10-10 m/sec) and a High Density Polyethylene (HDPE) geomembrane, of a thickness of 1.5 mm with a total permeability of 1×10-10m/sec. It is worth mentioning that in the Sanitary Landfill Sites a geomembrane of a permeability of 1×10-9 m/sec is placed.
To the tailings impoundment site will also be discharged the leachates from the mine area, which will be collected by a special drainage system which will be constructed over the geomembrane.
The surface runoff flows of the wider catchment basin will be collected through a containment dyke at the northern part of the facility and by the perimeter diversion channel downstream of the facility and will be discharged depending on the prevailing climatic conditions either in the water collection pond or downstream of the facility.
After the INCOTM(SO2/oxygen) cyanide destruction process, the filter cake will be transported with trucks and will be deposited in a properly constructed tailing repository of a total useful storage capacity of 6.9 Mm3.
After the closure of the mine, the rehabilitation of the tailings impoundment site will begin, with its covering with oxidized waste rock, geomembrane and finally with fertile cap soil. On the cap soil various endemic plants will be planted.
After an environmental monitoring period of at least 5 years, the Project area will be returned to the previously agreed land use.
After extensive research in the area of the Project (geological, hydrological and hydrochemical), as well as pumping tests, a sustainable water resources management plan has been elaborated, which guarantees its water supply while eliminating any possible adverse effect on surface and groundwater resources and the environment.
The main points regarding the Water Resources Management Plan of the Project are the following:
- For the water management a water collection pond will be constructed downstream of the facility.
- The surface runoffs of the wider catchment basin will be collected through a containment dyke at the northern part of the facility and by the perimeter diversion channels downstream of the facility and will be discharged depending on the prevailing climatic conditions either in the water collection pond or downstream of the facility.
- The surface runoffs within the facility will be collected by the perimeter diversion channels and will be discharged in the water collection pond.
- In the pond will also end up the leachates from the mine site, which will be collected by a special drainage system, which will be constructed over the geomembrane.
- The water of the surface runoff from the mine, the waste rock dumps, and the ore processing plant will also be channeled to the water collection pond.
- The actual water requirements, on an annual basis, of an average hydrological year, is 16m3/h and range from 11m3/h to 21m3/h in the wet and dryer periods respectively.
- In the area there are two geologically separate aquifers, a Tertiary and a Mesozoic one.
- The W2R well which is located in the Mesozoic metamorphic rocks aquifer, will be used for project needs, as its water is unsuitable for drinking or irrigation.
- The water from the W2R well can meet the plant requirements with absolute environmental safety even in extreme draught conditions.
- Perama village and the surrounding settlements use for drinking purposes and irrigation water that comes from the Tertiary aquifer.
- In the Perama Project, there will be no use of the Tertiary aquifer water, which is useful for the local communities.
- Well water shall be used only if the recycled water from the filter press and the water collection pond is not adequate to cover the requirements of the plant.
- “The W2R well can meet the total water requirements of the Project even in periods of extreme draught without causing any adverse environmental effect” – Hydrogeological Study, October 2003, Professor G. Kallergis, University of Patras, Greece.
The above data are included in detailed studies that have been carried out by big Greek and international research firms such as ECHMES, ENVECO and GOLDERS. They were subsequently updated by the study “Perama Project – Sustainable Water Resources Management in the Project Area” by professor G. Kallergis, University of Patras, Greece.