The longwall, now formally known as 3-1-11, is 220 metres long with an extraction panel of 750m. Situated at a depth of 450m, it will work in an average seam height of four metres.

Mechel said its investment in the project exceeded Rb838 million (US$12.8 million).

The longwall also includes a cutter-loader, belt car and crusher, drag bar conveyor, 400m and 1,500m belt conveyors, and a 130-section powered support system.

The mine also obtained a mobile vac air pump degreaser to ensure the system's production efficiency and labour safety.

"The longwall 3-1-11 with estimated coking coal reserves of 3.5 million tonnes is equipped with the newest mining machines acquired as part of Mechel's investment programme," Mechel mining management CEO Igor Khafizov said, confirming that its planned output monthly is targeted at 90,000t.

The longwall's launch comes after the operator said in late August that it had started Longwall 0-17-18 at the V I Lenina underground mine, also at Southern Kuzbass. That system came equipped with a 130-section powered support system, cutter-loader, burr mill, pit car loader and a longwall conveyor.

Southern Kuzbass Coal, founded in 1993, is made up of an underground mining department (Sibirginsk underground, New-Olzherassk underground, Lenin underground); an open mining department (Krasnogorsk open pit, Sibirginsk open pit, Olzherassk open pit); a coal washing and processing department (Sibir, Kuzbass, Tomusinsk, Krasnogorsk); and the Tomusinsky motor transport department.

As of the beginning of this year, the complex's in-situ reserves were estimated at about 1.8 billion tonnes.