**4.3 Environmental aspects**

*Iron Ores*

Generally, the analysis of the situation of underground mining in Kryvyi Rih reveals a threat of gradual reduction of the resource provision and consequent decline of the commercial potential. Iron ores in the amounts of the billions of tons are accounted at underground mining enterprises as so called balance iron ore reserve (meaning the resource which mining is economically feasible and which parameters satisfy accounting requirements). This resource can provide the basis for mining development for more than 100 years ahead. However, in fact, the situation is far from optimistic for individual enterprises and for the deposit as a whole. Currently, underground mining of naturally rich iron ores is carried out only at seven mines of three mining enterprises and one more underground mine exploits magnetite quartzites. Overall, during the last 10-15 years, the gap between the designed capacity and actual production of enterprises was reduced due to pressure from the market that forces the enterprises to adapt design solutions of current and new projects in order to minimize expenditures, increase technological efficiency and enhance competitiveness. However the drawbacks are not yet overcome and technology still lags behind the market demands, so capacity utilization of most mines does not exceed 70-80%. Such capacity utilization weakens competitiveness on the global market

In 1990, the share of rich ore in the total iron ore production in Kryvyi Rih was 26.3%, while in 1995 it was reduced to 23.5%, and at the end of 2019 – to 14%. Currently, compared to 2007 (the most successful year in the period from 1995 to 2019), the production volume decreased from 62.98 Mt. to 58.27 Mt. or by 7.5%. A

Key reasons for production decline of rich iron ores in Kryvyi Rih can be

1.Continuous and intensive exploitation of deposit as a whole, delineation of individual deposits to greater depths, decommissioning of unprofitable mines, and depletion of reserves result in lower resource endowment of existing mines.

2.Lack of efficient technologies for processing of extracted raw ore result in relatively low iron content of ore (55-57%), high losses (up to 12-15%) and ore

3.High rate of mining operations deepening (13-16 m per year) is coupled with limited technical capacity of hoisting installations as well as with general deterioration of mining and geological conditions at deeper horizons are

4.Financial aspects include constant growth in maintenance costs of existing facilities due to reduced levels of mining, increased mining capital and high development cost at new deeper horizons. Increased cost of fuel, energy and of

5.Some market-related problems shall be noted such as insufficient competitiveness of marketable products compared with the major global producers, low domestic demand and increasing volumes of sinter grade ore imports.

6.Investments to R&D are continuously insufficient thus impeding delivery of innovative technologies capable for addressing current industrial needs.

The problems listed above are accompanied by the lack of scientifically sound

strategy for underground mining on the national level. Due to long term and

processing equipment only exacerbate the current situation.

more significant drop is observed in comparison to 1990, making 59%.

and undermines Kryvyi Rih deposit's production potential.

followed by a decrease in the mines' productivity.

summarized as follows:

dilution (up to 10%) in mining.

**26**

Analysis of the environmental issues of iron ore mining requires separate study and goes beyond the scope of current chapter. Therefore we address this topic here very briefly.

Currently operating mining enterprises of Kryvyi Rih, including those operating in the flooding prevention mode, pump up to 40 Mm3 of ground water from mines and pits annually, of which highly mineralized water makes 16-17 Mm3 annually. Nearly 30 Mm3 of return water is in a continuous technological loop at the 5 MPPs. Tailing ponds (6 operating and 2 closed ones) of the mining enterprises occupy the area of 5 000 ha and contain over 2 billion m3 of ore concentration wastes. Dumps contain over 13.0 billion t of overburden rocks. Underground voids reach volume of 50 Mm3 . Overall, in Kryvyi Rih iron ore deposit on the area of 300 km2 , a great number of potentially hazardous objects such as underground mines, open pits, tailing ponds, industrial sites, disturbed land and underground voids are located.

#### **4.4 Iron ore quality**

The global output of iron ore is in compliance with dynamics of the world economy, yet, in general, development of iron ore mining is quite steady. Total production of crude iron ore has exceeded 3 billion t per year and has tripled since 1999. As anticipated by Fitch in Global Iron Ore Mining Outlook, global crude iron ore production will grow modestly from 3.348 billion t in 2019 to 3.482 billion t in 2028, which represents average annual growth of 0.2% during this period being a significant slowdown from an average growth of 4.5% during 2009-2018 [11]. Therefore, taking into account growing iron ore mining capacities, especially in Brazil, iron ore market shall become

even more competitive. In terms of international competiveness, the position of Ukraine amongst the other major global suppliers is rather uncertain. For instance, iron content in sinter grade ore supplied from Brazil is 66-67%, from Australia – 61-62%, from Sweden – 67% with silica content in the range of 0.5-3.5%, whereas iron content in Ukraine's sinter grade ore makes 56-61% with silica content of 18-21.5% [1].

At present, Kryvyi Rih underground mines enhance quality of marketable ore through increasing iron content in the last portion of ore drawn from blocks to 50-52% instead of previously standard 46% as well as through screening out the lean lumps with iron content of 43-48% at the crushing-grading factory. Although this assisted to a general trend of increasing the iron content in the concentrate (evolution of average value for Ukraine is shown in **Figure 9**), application of such methods increases also ore losses in situ and iron losses during concentration and, finally, negatively impacts the enterprise's economy. At the same time, quality of ferruginous quartzites mined at open pits in terms of iron content and content of impurities was not improved. Generally, the quality of marketable iron ore product remains well behind the advanced foreign practices, despite certain improvements achieved at some enterprises [12].
