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KIRUNA IRON ORE MINE, SWEDEN

With an ore body 4km long, 80m thick and reaching a depth of 2km, LKABsKiruna is the worlds largest, most modern underground iron ore mine. Sincemining began here over 100 years ago, LKAB has produced over 950Mt of ore,

yet only one-third of the original ore body has been extracted. Since mid-1999,Kirunas haulage level at a depth of 775m has been replaced by the next leveldown at 1,045m, which will support production until 2018. The operation employs1,800 people, of whom 400 work in the mine.

In 2004, Kiruna produced 14.5Mt of iron ore products out of LKAB's total of22.3Mt, maintaining the general relationship that it produces around two-thirds ofthe company's total Swedish production. 11.5Mt of Kiruna's output was sold aspellets. In 2004, LKAB achieved sales of iron ore products totalling 22.8Mt, ofwhich 17.2Mt were exported and 5.6Mt were delivered to customers in Sweden.

GEOLOGY AND RESERVES

The Kiruna orebody was formed at around 1,600Ma following intense volcanicactivity with the precipitation of iron-rich solutions on to a syenite porphyryfootwall. The ore bed was then covered by further volcanic deposits (quartzporphyry) and sedimetary rocks before being tilted to its current dip of 50 to 60.The ore contains a very pure magnetite-apatite mix, containing more than 60%iron and an average of 0.9% phosphorus. Black ore contains less apatite thangrey ore.

The original reserve at Kiruna was some 1,800Mt. As of the end of 2004, LKAB

estimated that the current proven reserve at the mine is 657Mt grading 48.3%iron, with probable reserves of 140Mt at 46.5% iron. Measured, indicated andinferred resources add a further 500Mt-plus to the inventory, with explorationcontinuing to identify further resources at depth.

KUJ2000

The KUJ2000 project has integrated the move down from the 775m level haulageto 1,045m with the upgrading of all of the mines ore handling systems, which cannow handle 26Mt/y. Components include the new automated rail transportsystem on the 1,045m level, uprating the hoists and crushers, and increasing the

ventilation system capacity. Seven 500t-capacity shuttle trains, controlled fromthe 775m level, collect ore from ten groups of ore passes, and deliver it to one offour crushing stations. 100mm ore is then skip hoisted in two stages to the775m level and then to surface. During 2003, LKAB invested some $23 million innew locomotives and ore cars.

The mine is divided into eight production areas, each containing its own group ofore passes and ventilation systems. Mining the 16.5km of ventilation shafts was

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carried out by SIAB using Indau 500 raise borers, while Skanska Raise Drillingdeveloped a total of 32 ore passes between the 775m and 1,045m levels usingTamrock and Robbins raise borers. Alimak developed two special units based onits RCM-6 system to reinforce the ore passes with cable bolts and shotcrete asnecessary.

MINING

Ore is mined using sublevel caving, with sublevels spaced at 28.5m vertically.With a burden of 3.03.5m per ring, this yields around 8,500t for each blast.LKAB subsidiary Kimit AB supplies the explosives and prepares the holes forblasting.

Electric-powered, remote-controlled drilling and ore handling equipment suppliedby Atlas Copco and Tamrock is widely used. After blasting, load-haul-dumpmachines carry the run-of-mine ore to the nearest ore pass, from which it is

loaded automatically on to one of the trains operating on the 1,045m level. Afterprimary crushing, sampling using a Morgrdshammer automatic sampler toobtain the apatite and magnetite contents, and hoisting to surface, the ore isprocessed in Kirunas complex of a sorting plant, two concentrators and twopellet plants to give pellet and sinter fines products. Some ore is moved by rail toLKABs Svappavaara plant for pelletisation. Products are hauled by rail to theports of Narvik (Norway) or Lule for shipment, with LKAB having spent around$175 million on upgrading the rail system with track improvements and newrolling stock.