Geographic and economic characteristic

The placer deposit of diamonds of the Billyakh river is located in the southern part of Anabarskiy ulus of the Republic of Sakha (Yakutia), 320 km from the Arctic Ocean coast, in the basin of the middle-upper course of the Billyakh river, right tributary of the Anabar river. The nearest inhabited locality is the settlement of Ebelyakh. There is a platform suitable for receiving helicopters and type AN-2 airplanes.
The administrative centre of Anabarskiy ulus – the nasleg of Saskylah - is located northward from the project area on the Anabar river. In the settlement there is an airport intended for all-the-year-round reception of AN-24, AN-26 airplanes and MI-8, MI-26 helicopters.
Transport communications of the region are effected by sea, by air from the cities of Mirny, Udachny, Yakutsk, by motor transport via the year-round motorway through the cities of Mirny, and Udachny.
The deposit is located beyond the Arctic Circle, in the northern zone of the larch taiga. The vegetation is represented by open larches. There is no building timber in the region. Available reserves of vegetation are suitable only for temporary construction and procurement of fire wood.
The soil cover is poorly developed. Almost everywhere, except for river sand bars, the soil is covered with moss carpet. Most part of the territory is water-logged.
The region’s fauna is represented by wild reindeers, polar foxes, wolfs, hares, tundra partridge, etc.
Ground elevations at the deposit site vary from +90 m to +120 m.
The level of economic development of Anabarskiy ulus as of today is low; the ulus is subsidised  at the expense of the republic budget, however it has favourable outlooks associated with the development of mining industry.
The deterrents of the economic development include, first of all, geographical remoteness from central regions and other settlements and harsh weather conditions.
The manpower index of the ulus is one of the lowest in the republic. Currently the population is about 3.6 thousand people. The most part of them are indigenous peoples of the North. The indigenous population is mainly engaged in reindeer breeding, fishery and fur farming.

Climatic characteristic

The climate of the region is sharply continental and is characterised by a long cold winter (7-8 months) and a moderately warm short summer (2-2.5 months). Average temperature of January is minus 35.5°C, that of July, +11.7°C. Average annual temperature is minus 14°C. The annual precipitation varies from 215 to 252 mm. The snow cover level usually does not exceed 0.5 m, but in places of snow drifts it reaches 2 m. The forest-tundra region is characterized by a seasonal change of directions of aerial currents. In the winter southeast and northwest winds prevail, while in the summer – east ones predominate. In winter time about 50 days with blizzards are normally registered.

Hydrological characteristic

The surface of the project area is essentially a slightly sloping relatively low plateau, divided to various extent by river valleys.
The Billyakh river is 57 km long and has a river bed width of 3 to 20 m. According to the nourishment conditions and the water regime particularities the Billyakh river is referred to the East Siberian type of rivers with a high spring flood and frequent rain high waters. The lowest water level has been registered in July. Water level and flow rate during the summer period are rather changeful. The river is fed at the expense of spring snow melting and summer/autumn rains (combined with an intensive thawing of perennially frozen rock). Usually there are two high waters: a spring one (in the beginning of June) and a summer/autumn one (in the beginning of August).
The winter regime of the Billyakh river has all specific features characteristic of the rivers of the subarctic zone of Yakutia. In the winter the Billyakh river and its tributaries completely freeze through at natural bars. The ice thickness varies from 0.5 to 1.2 m. The rivers break-up in the beginning of June, and freeze-up in the end of September. In terms of fishery the Billyakh river is of no interest.
Bayou, relict and thermokarst lakes are rather widespread. Their form varies from the horseshoe to the roundish ones. The sizes of lakes vary from tens of metres to 0.2-0.3 km in diameter, with a depth from 0.5 to 5 m.
Surface waters are fresh, suitable for household, drinking and technical purposes.
Since 1999, OAO Nizhne-Lenskoye has been carrying out operational exploration and pilot development of the alluvial deposit using open-cut separate mining method in the upper reaches of the valley (exploration and operation unit Billyakh).

Company structure and background

According to the licence agreement YaKU 01574 a placer deposit of diamonds on the Billyakh river was allocated to OAO Nizhne-Lenskoye for exploration and development. The exploitation of the placer deposit was started in 1999 by State Mining-and-Geological Enterprise Nizhne-Lenskoye (nowadays OAO Nizhne-Lenskoye) by creation of the Billyakh division for pilot development of the deposit for the purpose of substantiation of the most efficient and environmentally friendly process of development of reserves, the most rational sand excavation and benefication method, operational verification of reserves made on the basis of geologic researches.
On the basis of data obtained in 2002 the GUL institute Sibgiprozoloto was assigned a task to develop a feasibility report of exploration conditions for recalculation of the deposit reserves, as well as a detailed deposit development project using two production sections: Billyakh and Tiglikit, incorporated as structural subdivisions by the production unit - opencast Billyakh subordinated to OAO Nizhne-Lenskoye. Production section Billyakh uses the existing pilot factory, repair shops, warehouses of petroleum products and explosives, a diesel power station, a shift camp with sanitary- and consumer services.