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Контекст:

The Volga River plays an essential role in Russian oil and product transportation. Between the months of April and November, when it is free of ice, TNK-BP and other oil companies use the river to move their cargoes in small lots of 4000 Mts. This is driven by superior economics compared to rail exports, however, it is an extremely complex operation involving the shipment of over 1.5 million tonnes, with each barge travelling 2500 km via narrow and hazardous navigation channels.

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