The company operates the project through its wholly owned Turkish subsidiary, Tuprag Metal Madencilik (Tuprag). Efemcukuru consists of two pre-operation licences comprising 3,072 ha. The terrain is rugged, with elevations ranging from 520 to 760 metres, and the region hosts a mixture of forest and agricultural lands. Rainfall in the area is seasonal, with an average of 740 mm of precipitation falling in the winter months. Temperatures are moderate, influenced by the proximity to the Aegean Sea.
The property lies 20 km southwest of Izmir, a port city with a population of about 3 million. The village of Efemcukuru is the nearest settlement, about 2 km south of the project. The property is accessible via paved and unpaved roads that connect the village with larger population centres.
Eldorado discovered gold on the property in 1992 and 1993 during a program of stream-sediment, soil and chip sampling, followed by trenching and 3,500 metres of core drilling. The Kestane Beleni vein was identified at a surface outcrop, where evidence of small-scale historic workings was found. An additional 4,092 metres of diamond drilling were completed in 1997 in order to delineate the initial resource.
A total of 12,000 metres of HQ (63.5-mm core diameter) drilling has been compiled to produce the present geologic model and resource estimate.
The Efemcukuru resource occupies the North, Middle and South ore shoots, and are all part of the 1,100-metre-long Kestane Beleni vein structure. The total measured indicated and inferred resource is pegged at 2.5 million tonnes grading 13.71 grams gold per tonne, or 1.1 million contained ounces.
The process of obtaining permits for industrial or mineral operations in Turkey is similar to that followed in Europe and North America. First, a site selection permit is required in order to release the project site for the intended use. Following the definition of physical, operational and environmental perimeters, an environmental impact assessment (EIA) is carried out by an independent, government-authorized organization. All subsequent construction and operating permits are based on this assessment.
Eldorado in the process of collecting baseline data for its EIA, though it recently encountered delays at the municipal level. The problem stems from the fact that the project lies in the watershed of a proposed reservoir, and this watershed is considered too small to support the construction of a dam. Consequently, the local municipality could decide to cancel the project altogether.
“It’s a question of perseverance and following the right path,” said Eldorado President Paul Wright, who spoke with The Northern Miner during a recent site visit. He added that he hopes to have the EIA completed by year-end, whereupon the company would begin carrying out additional core drilling to delineate reserves and resources. Pilot-scale metallurgical tests would follow, and Eldorado hopes to have a bankable feasibility study completed by the first quarter of 2002. Construction is tentatively scheduled for the fourth quarter of that same year, with startup slated for the fourth quarter of 2003.
Fine gold
The Kestane Beleni vein structure is hosted in a sedimentary package composed dominantly of hornfels and phyllites and is controlled by northwesterly trending structures. The vein consists of quartz and rhodonite, with associated sulphide mineralization (mainly pyrite with minor pyrrhotite, chalcopyrite, sphalerite and galena). Widths of mineralization vary from less than 1 metre to greater than 15 metres. Mineralization tends to occur as open-space fillings, multi-stage breccia and quartz-carbonate veinlets. Host rock minerals include quartz, rhodonite and rhodochrosite. Most of the gold is fine (2.5-50 microns) and occurs both as free grains in quartz and carbonate and as inclusions in sulphide minerals. Lower-grade stockwork mineralization occurs locally between ore shoots. Mineralization occurs in both the hangingwall and footwall contacts, and the vein dips 60-80 to the northeast.
A second, less continuous vein, dubbed Kokarpinar, lies 750 metres to the north of the Kestane Beleni vein. The Kokarpinar vein has been traced over 2,500 metres
“We haven’t really done a lot of work on the Kokarpinar structure,” said Wright. “The little we have done has not given us the same encouragement that we have regarding the Kestane Beleni vein.” One reason for this may be the vein’s structural complexity. However, as David Bickford, Tuprag’s general manager, points out, there may be some downdip potential for mineralization.
Results from drill programs in 1996-1997 indicate that mineralization in the Kestane Beleni vein extends to a depth of 300 metres and remains open at depth. Eldorado states that the grade of the gold mineralization has been enhanced by secondary enrichment in the top 100 metres of the vein.
Ore shoots
The South Ore Shoot has a measured and indicated resource estimated at 859,000 tonnes averaging 12.69 grams gold per tonne (350,417 contained ounces). The inferred portion of the resource weighs in at 456,000 tonnes grading 11.05 grams gold per tonne (161,998 contained ounces).
The Middle Ore shoot has a measured and indicated resource of about 934,000 tonnes grading 16.09 grams gold, or 483,231 contained ounces. The inferred portion of this resource is estimated to be 142,000 tonnes grading 15.92 grams gold (72,703 contained ounces).
The North Ore Shoot has a measured and indicated resource of 81,000 tonnes grading 9.75 grams gold, (25,381 contained ounces). The inferred portion of the resource stands at 61,000 tonnes averaging 9.75 grams gold, (19,124 contained ounces).
Calculations are based on a gold price of US$300 per oz. and a cutoff grade of 6 grams per tonne. The resource estimation was performed by Micon International. Mining studies were contracted to H.A. Simons. The process plan layout and costing was performed by Kilborn Engineering Pacific; the tailings studies, by Klohn Crippen Consultants.
The prefeasibility study, completed in March 1999, envisages a production rate of 250,000 tonnes per year to recover an average 87,000 ounces of gold annually. The mine life, based on the known resource, is expected to be 10 years; it will employ 193 people.
Adit mining
To reduce the impact of the mining operation on the local environment, Eldorado decided to opt for an underground mining operation, with adits accessible from the valley floor.
“The mining approach is fairly simple,” said Dale Churcher, Eldorado’s manager of project development. “Adit access will come through the hangingwall side and cut through the gap between the middle and the south ore shoots, then drive through the ore zone into the footwall zone. All the shoots will have ramp access.”
Operating costs at Efemcukuru are pegged at US$176 per oz., whereas the capital cost is estimated to be US$45 million.
The after-tax net present value, based on an 8% discount rate, is set at US$13.4 million (or US$29.6 million before taxes and royalties). The after-tax internal rate of return is estimated at 19.1%. Before taxes, it is 32%.
Extensive metallurgical tests have led to the selection of flotation and gravity separation for gold recovery to a concentrate. Run-of-mine material will be sent through a grizzly crusher and then to a semi-autogenous mill at a rate of 800 tonnes per day. The material will be further crushed in a ball mill and sent through a series of concentrator and cleaner flotation circuits, and then to scavenger cells. The gravity concentrate will be sent through a series of Nelson concentrators and smelted on-site to produce gold dor, whereas flotation concentrates will be bagged and shipped for processing off-site. Gold recoveries are anticipated to be in the range of 86-88%.
Eldorado had originally planned to ship the concentrate to its Sao Bento operation in Brazil, where carbon-in-leach technology would be employed. The flotation concentrate would be subject to a regrind and then to direct cyanidation. According to this plan, a storage facility would be constructed at the port of Izmir. Instead, however, the company is now considering sending the concentrate to its Kisladag operation, near the Turkish town of Usak, 300 km to the east.
Infrastructure at Efemcukuru includes a 20-km overland electrical powerline to service the mine facilities, while providing additional capacity to the local village. Potable water will be obtained from the local drainage.
A de-watering process will be used to treat the mine tailings. The process will produce a semi-dry product that can be disposed of on surface as a landfill material, which would be resistant to seismic activity. The de-watered tailings would also provide a high-density underground backfill and, in turn, decrease the size of surface disposal sites.
Eldorado has 83.7 million shares fully diluted.
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