1-coal.pdf

World Placer Journal – 2009, 9, v volume 9, pages 24-47. EMI Environmental Paper #2 – September 2009

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Remote sensing of the coal sector in China and Mongolia Mongoli

Purpose of study

Eco-Minex International Ltd., Apt.14, Bldg. 40, 1/40000 Microdistrict, Sukhbaatar District, Ulaanbaatar 210644, P.O.B. 242, Mongolia. E-mail: [email protected]

To achieve this, we searched for coal activities in northern China to serve as models – good and bad – to help guide Mongolia in managing its spate of new coal mines.

Robin Grayson MSc and Chimed-Erdene Erdene Baatar MBA

About the authors

The overall purpose rpose of the study iis to assist the reader to gain a better visual understanding of Mongolia Mongolia’s Coal Rush and to draw attention to lessons that can be learned from China’s ’s coal industry. industry

The value of Google Earth in highlighting environmental issues is illustrated by images of coal seams on fire fire, acid mine waters contaminating streams treams, and coal dust affecting the e nomadic pastures of the Gobi Desert. Chimee completed her Masters Degree in Business Administration in 2004 with the Maastricht School of Management, and has analysed Mongolia’s ‘coal rush’ by fieldwork and remote sensing. She has a special interest in the complex relationships between mining companies and artisanal miners, and is an officer of Ulaanbaatar Rotary Club. Robin is a qualified geologist and ecologist, and has prospected for coal in the South Lancashire Coalfield, Hindu Kush and the Gobi Desert. He produced new structural maps of the coalfields of northern England for the oil industry, and was an expert witness at several major UK public inquiries into opencast coal mining mining.

A surprise was s the ease of track tracking spills from rom coal trucks on dirt roads across the Gobi Desert, often many kilometres from the mine source. The study presents evidence from Google Earth of the merit in insisting on rail transport of coal on environmental, health and safety grounds, rather than trucking by road, and for adopting rail in transporting waste to the dumps. An unexpected outcome was the detection of a system of open fractures along a 5.5.km wall of a large coa coal mine in Xinjiang, indicating serious rious collapse collapse. Special thanks are due to Lotus Resources PLC for technical and logistical support.

Figure 1.

images of the coal mining industry

TOP – New rail ail loading facility at the Shivee Ovoo Mine on the Trans-Mongolian Railway. (photo: Chimed Chimed-Erdene Baatar) UPPER MIDDLE – A new mine shaft being sunk by a Chinese company at Nailakh. (photo: Chimed-Erdene Erdene Baatar) Baatar LOWER MIDDLE – A new mine shaft being sunk by informal miners (‘ninjas’) att Nailakh. (photo: Chimed-Erdene Chimed Baatar) BOTTOM – Satellite image of a traffic jam of coal trucks at the entrance to the Nariin Sukhait Coal Mine e in the Gobi Desert Desert. All is destined for export via dirt roads to China China. (image: Google Earth)

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Contents Purpose of study...........................................................24 1: Coping with a coal rush ........................................25 2: Coal mines on Google Earth..................................26 3: Coal dust and ‘other’ dust .....................................26 4: Is coal detectable on Google Earth? ......................26 5: Large mine in Xinjiang – lessons for Mongolia .......27 6: Collapse of north face of Sandaoling Mine .............27 7: Dumps of Sandaoling Mine ...................................28 8: Dust prevention....................................................28 9: Risk of dump fires ................................................29 10: Risk of open pit fires.............................................30 11: Risk of virgin coal fires .........................................30 12: Coal fires in China ................................................31 13: Coal fires in Mongolia ...........................................31 14: Risk of acid mine drainage....................................32 15: Options for waste transport ..................................33 16: Options for coal output.........................................34 17: Coal transport – rail option ...................................35 18: Issues at rail loading sites.....................................36 19: Coal transport – road option .................................37 20: Coal haul roads from mines ..................................38 21: Haul road issue – coal spills ..................................39 22: Haul road issue – multi-tracks.................................40 23: Coal-burning power plants in Ulaanbaatar .............41 24: Pulverised fuel ash (PFA) in Ulaanbaatar ...............42 25: PFA and radon gas in Ulaanbaatar ........................42 26: Time series on Google Earth .................................43 27: Coal seams on Google Earth .................................44 28: Coal briquettes in China........................................45 29: Discussion............................................................45 30: Recommendations ................................................46 31: Acknowledgements...............................................46 32: References ...........................................................46

With dwindling cash and profits too low to warrant investment, the large mines became inefficient, production targets unrealistic and unit costs rocketed. Notoriously the Sharin Gol mine “went on strike” and refused to sell coal to the power stations of Darkhan or Erdenet cities at the uneconomic price set by the Government.

Figure 2. coal mine on strike A banner over the locked gate of Sharin Gol Coal Mine proclaims: “2007.09.01 – some Sharin Gol miners are on strike, to stop coal being transported to the Darkhan and Erdenet power stations from this date”. (photo: Chimed-Erdene Baatar)

Such dire confrontations are eventually settled or the cities’ residents and infrastructure would perish in the harsh Mongolian winter. But the low prices and uncertainty have deterred investment into the ex-Soviet flagship mines of Sharin Gol and Baganuur [2]. Today both struggle with antiquated equipment and try to open up blocks of reserves without sufficient funds.

1. Coping with a coal rush Mongolia only began to gain an industrialized economy decades after the Soviet Union industrial-military complex had matured. Late Soviet investment was barely sufficient to barely meet Mongolia’s modest need for heat and power. By the time the system collapsed, Mongolia had scant experience in financial, technical, environmental, regulatory or socioeconomic issues of large coal mines. Yet the Soviets did prove large coalfields whose reserves were added to the ‘State balance’ and voluminous tomes filed in the then-secret State archives. Disintegration of the Soviet Union caused economic collapse and Mongolia de-industrialised rapidly. In response, the Government made public the State Geofund and with the assistance of the World Bank and IFC introduced a fast-track first-come first-served mineral cadastre. This triggered a Gold Rush in placer mining which as part of the Government Gold Plan pumped liquidity into the banking system and nascent private sector and stabilised the national currency. In contrast, Mongolia’s coal sector developed in a lob-sided manner. Private companies opened small coal mines near Ulaanbaatar and close to rural markets. But large mines were cash-starved by Governments capping coal prices to hold down prices of electricity and heating.

Figure 3. inefficient mining The draglines have insufficient reach to fling waste out of the open pit of Baganuur Coal Mine. (photo: Bernd Braeutigam)

Yet Mongolia has to shift from this byzantine scenario to manage a Coal Rush of global importance, driven by China’s insatiable appetite for energy and fuelled by a Soviet Geofund that archived billions of tons of coal. Yet few Mongolians are aware of what a modern coal mine looks like or how it can produce low-cost coal profitably year-after-year with minimum impact. Mongolia risks repeating serious mistakes that have cost the west billions of dollars and a century to unravel; and today these mistakes are in evidence in China where ‘Coal is King’. To assist the debate, we present visual evidence from China of how to stimulate the coal sector – and pitfalls to avoid! Finally we present some strong recommendations for Mongolia’s policy makers.

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2. Coal mines on Google oogle Earth Coal mines were detected in Google Earth (GE) and plotted as normal kmz files. Pins were chosen hosen from the GE selection, and coloured from the GE colour palette. To avoid clutter, pins and text were downsized. ‘Flag pins’ were added for artisanal coal mining sites,, and black truck pins used where coal trucks were seen. Special pins were added for indications of acid mine drainage (AMD), coal fires, coal-fired fired power plants, coal briquette plants. In addition, pins were added for signs of coal oal exploration by drilling and pitting, coal spillages from trucks and multimulti tracking of coal haul roads.

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4. Is coal detectable on Google Earth? We have detected coal seams on high high-definition Google Earth in northern China and southern Mongolia, particularly in rocky desert regions. This is made possible by solid coal having a dull blackish colour, in sstark contrast with the pale sandstones, siltstones and shaley clays with which coal so often is associated. Where clay rocks predominate, or where sandstones are soft, then the coal seams can be the hardest local rock in the sedimentary sequence and so the seams may sometimes stand proud as ribs through the thin desert soils. When coal is disturbed by mining, including artisanal and small-scale scale mining (ASM), then the inevitable spillages of powdery broken coal form tell-tale tale black to blackishblackish blue areas on Google Earth.

Figure 4. coal mines in the study area Coal oal mines in Mongolia and north China visible in high definition Google Earth and used in the study. (image: image: Google Earth)

3. Coal dust and ‘other’ ’ dust As a prelude to this paper it is useful to clarify what is meant by dust in the context of coal mining. Coal mines commonly produce three different types of dust. Coal dust: blown from the mine floor and face, or from coal stockpiles and trucks. Less obvious but often more serious is the paler low carbon silica-rich rich dust blown from dumps of stripped overburden and flung into the air from haul tracks by coal trucks.

Figure 7. coal visible on Google Earth Coal’s dull black colour dominates this view of the coal yards west of Beijing. Stockpiles of coal are surrounded by coal-covered coal ground (image: Google Earth)

Figure 5. coal dustt excursion from a coal mine Coal dust at Shivee Ovoo Coal Mine. (photo: Robin Grayson)

Figure 6. Silica dust in a gentle dust-storm storm Silica-rich dust blowing across a road. (photo: Robin Grayson)

The coal dust and silica dust often become mixed along haul roads to form a bright pale grey cover of dust. Inter-seam dust:: blown from dumps of inter-seam inter waste with variable carbon and often high clay content. Silica dust:: dust blown from overburden dumps or flung into the air from dirt roads by coal trucks.

Figure 8. coal contrasts with arid ground The black colour of coal oal is often in sharp contrast to the pale background colour of dry humus-poor poor bare soils soils, as here in the informal coal mines at Nailakh. (photo: Robin Grayson)

Caution is required, for coal is mimicked by spillages of oil, areas of black shale or slate, a and by wet organicrich clays. However, a characteristic of coal is a tendency to powder once disturbed and so streaks of coal dust on the ground can often be seen.

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5. Large mine in Xinjiang – lessons for Mongolia

6. Collapse of north face of Sandaoling Mine

The Xinjiang Uyghur Autonomous Region produces about 40% of China’s coal, and includes a wide range of coal mines in terms of size, age and mining method. Xinjiang’s large Sandaoling Mine is instructive for Mongolia. For, although the mine is over 50 years old, it demonstrates issues that can arise when developing a large open-pit coal mine in a harshly continental arid environment. The main open pit is about 50 metres deep and up to 200 metres wide, and traces a narrow and gently sinuous course along the strike of Jurassic coals [31] for about 5.5 kilometres. These parameters are within the size range anticipated for several open pits envisaged for Mongolia’s Gobi desert in the short-term.

A remarkable feature of the Sandaoling Mine is that the entire north face of the mine is in a state of general instability and wholesale collapse along a 5.5-kilometre system of open cracks. It is apparent that 100-metre wide masses of material have episodically slipped onto the floor of the mine, with potentially profound implications for mine safety and efficiency. Many open fissures are present, often generating blocks of rubble of 5 to 10 metres in size. The precise cause of the collapse is not apparent, but a contributory factor may be the gentle but steady surface gradient estimated from Google Earth to be about 20 metres per kilometre. It seems that a low-angle detachment surface has formed at or below the junction of the dark Jurassic coal-bearing deposits with the cover of pale overburden. Detachment would be facilitated if as expected the coal-bearing sequence is an aquaclude with clays of low-shear strength, whereas the cover sequence is assumed to be a highly porous aquifer.

Figure 9. Sandaoling Coal Mine High-definition Google Earth image with a cloudless sky, revealing the entire layout of Sandaoling open-pit coal mine and its dumps. Sandaoling city is visible at the top-right. (image: Google Earth)

Google Earth reveals mining is by a series of six to eight benches being excavated by large electric-powered face shovels with 11m bodies and 13m booms. These feed rail wagons on a fleet of dedicated merry-go-round trains that ply to-and-fro the dumps or coal stocking areas.

Figure 10. benches of Sandaoling Coal Mine A view down inside the open pit showing seven of the mine benches. The lighter benches are of overlying overburden that is being stripped, while the darker lower layers are of the coal seams and associated beds. (image: Google Earth)

Haulage is entirely by steam locomotives although these are expected to be withdrawn and replaced by diesel traction in the near future [30, 34].

Figure 11. collapse of north face Looking west to view the dramatic slide of pale overburden onto the floor of the open pit. (image: Google Earth)

Figure 12. collapse of north face A higher view, showing the layout of the arcuate open fissure system. (image: Google Earth)

The openness of the fissures makes it unlikely that the collapsed masses might be a rollover on a listric detachment. Instead it seems to be a valley-camber collapse, whereby the more it cambers then the more the fissures open up.

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7. Dumps of Sandaoling Mine

8. Dust prevention

The energy expended in hauling trainloads of waste out of the Sandaoling Mine is evident. The round-trip is a considerable distance. Yet this is a desert environment with no physical, cultural or land value constraints. Accordingly the mine has enjoyed the freedom to spread the dumps over a large footprint. This reduces the haulage gradient so trimming haulage costs. The operating cost of rail haulage is unknown, but is thought to compare very favourably with that of the large fleet of dump trucks that would otherwise be required.

While the mine footprint might be deemed excessive by some environmentalists, a bonus is that the evolving landform is consistently more streamlined than would otherwise be possible, and therefore wind erosion and dust generation are reduced. Once a dust excursion has begun it would be virtually impossible to stop until all the fines had blown away and a protective lag carpet of gravel inhibited further excursions of dust.

Figure 15. smooth landform of the dumps The overall shape of the main dumps presents a reasonably streamlined outline to wind. (image: Google Earth)

Figure 13. lateral accretion of the dumps The main dump accreting sideward by fresh material being delivered by rail and piled neatly into arcuate ribs by a large earth-moving machine. This may be face shovel or a walking dragline. Note the carpet of rubble blocks that have tumbled onto the ground at the base of the slope. (image: Google Earth)

Figure 14. vertical accretion of the dumps A large earth-moving machine that appears to be raising the surface of the dump by using fresh material delivered by the railway track to its immediate right. (image: Google Earth)

Using rail trucks as the sole means of transport to the dumps generates far less dust than would be the case if a large fleet of dump trucks were shuttling to-and-fro. While dust suppression is theoretically possible, in practice this is rarely satisfactory in a desert environment, not only due to a lack of sufficient water and the evaporation of whatever water is sprayed, but also due to spillages of excessive uncovered loads, the jolting of laden trucks on dirt roads, the bouncing of speeding empty trucks returning to the mine, and not least due to the dustgenerating turbulence in the wake of every truck. Likewise, using face shovels instead of dozers and scrapers for modelling the surface of the dumps means that dust generation is significantly reduced.

Figure 16. smooth landform of the dumps The leading edge of the main dump showing the ribbed nearhorizontal top, and the steep leading edge. (image: Google Earth)

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9. Risk of dump fires The extensive dumps of the Sandaoling Mine bear few signs of significant combustion. This is remarkable for the mine is in China’s ‘coal fire risk region’ [1, 11]. The reason that the dumps have large avoided fires is evident on Google Earth. The dumps are seen to be dominated not by dark coaly waste but by spreads of pale overburden waste that has very low carbon content and so no tendency to combust. Indeed it could be used as an inert blanket to inhibit or suppress coal fires – a clear advantage over the new mines planned for Mongolia that have little or no inert material in the overburden. Nevertheless a spectacular fire raging on the dump of Sandaoling Mine is clearly visible on Google Earth. The fire is not in normal dumped waste, and appears to be burning masses of train-loads of smouldering coaly material evacuated from the mine on a contingency basis to the dumps. Here it is free to burn itself out safely without unduly imperilling the mine or its workers.

Figure 17. mine dump on fire Part of a one kilometre ribbon of fire on the Sandaoling Mine th dumps on 17 September 2004. (image: Google Earth)

Tracing the burning material on the dumps back to its source reveals large areas of reddish-brown material on the floor of the open pit. We interpret this as being burnt coal that is now clinker and ash, plus associated carbonaceous clayey material that has combusted to create ‘red shale’. As usual in coal fires worldwide, the tell-tale orange-red brick colour is due to iron oxides such as haematite produced by thermal oxidation of pyrite.

Figure 18. removal of burning material The ‘red shale’ areas of the open pit indicate where coal fires have occurred. The ‘active fires’ are interpreted as being burning material hauled by train out of the pit. (image: Google Earth)

The overall evidence suggests that rail haulage has a clear advantage over truck haulage in efficiently and safely evacuating burning material from a large open pit.

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10.

Risk of open pit fires

The Sandaoling Mine has a long history of dealing with extensive fires in its large open pit. This struggle has continued in recent years, with many visitors taking photos and videos of the fires [34]. The images are commonly of small smouldering fires scattered across the floor of the open pit, typical of internal combustion. A few night-time images indicate flames are present. Flames, smoke and steam are not convincingly visible on Google Earth, and it is presumed that the fires are too small, too dry and too scattered. But clearly visible are areas of ‘red shale’ that indicate extensive fires have occurred. This does not, in itself, mean that such fires are recent, for ‘red shale’ in Inner Mongolia has also been produced by large coal fires triggered by natural internal combustion thousands of years ago [19]. Of interest is ‘red shale’ with the collapsed east face of the open pit. This may be coincidence, but a history of coal fires would be expected to produce considerable voids in the burnt zones rendering the pale overburden liable to crack and slide into the open pit. Such cracks, albeit smaller, have been mapped around the Wuda coal fires of Inner Mongolia [35].

Figure 19. red shale next to collapsed face The most prominent ‘red shale’ areas seem to be juxtaposed with some of the most severe collapses visible along the north wall of the open pit of Sandaoling Mine. (image: Google Earth)

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Risk of virgin coal fires

Evidence of coal fires affecting virgin (unmined) coal is common in Inner Mongolia [25, 26, 33] and Xinjiang [38], and is also reported at Tavan Tolgoi, Nariin Sukhait and Ukhaa Khudag in Mongolia [19]. While flames, smoke, steam and sulphurous smell are to be expected this is not always so. Virgin coal fires may reach an equilibrium state of quiescence for long periods during which few such signs are manifest. During periods of quiescence, one tell-tale sign may still persist, namely the presence of a chain of crown holes along the strike of the coal seam. Crown holes are roughly circular collapses of the ground surface triggered by upwardly migrating caverns produced by collapse of the overburden due to reduction in volume of the coal. The volume of coal is reduced by the loss of its carbon and sulphur content by combustion, the driving off of moisture content, and general shrinkage of clays. Good examples of crown holes are visible on Google Earth along an 800m long zone beyond the western margin of the open pit of the Sandaoling Mine. We attribute the crown holes to natural collapse of the ground above ancient underground coal fires. Crown holes are also commonly created by collapse of underground mine workings particularly those using pillar-and-stall (= roomand-pillar) methods of partial extraction. However the crown holes observed on Google Earth are quite large, often in excess of 10-15m in diameter demanding the loss of volume underground to be in excess of what might be expected from normal underground coal mining.

Figure 20. crown holes along the strike of the coal Crown holes beyond the advancing western end of the open pit of Sandaoling Mine. A group of eight fresh crown holes are visible on the right, presumably triggered by the advancing pit, as evidenced by the largest crown hole now acting as a focus for open fractures extending to pit. In the top centre is a large but somewhat indistinct crown hole that is ringed by open fractures in the ground bending down into the cavern below. In the top left is a string of as-yet stable crown holes. (image: Google Earth)

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Coal fires in China

While the Sandaoling Mine is instructive regarding coal fires and how to combat them, many more exist elsewhere in China and are much more serious. Some of the worst in the world are in the Wuhai coalfield, where a pall of smoke and acidic vapour from coal fires hides much of the ground surface in a haze of pollution. While much of the hazard is due to industrial pollution from coalburning power plants, heating plants and metallurgical plants, a large amount is due to out-of-control control fires at coal mines and on coal waste dumps. Coal fires in China were estimated to have consumed 100-200 million tons of coal in 1992 [12]. ]. If so, then these fires released 2-3% of the world’s output of CO2 from burning fossil fuel. But this figure has been revised down to 10-20 20 million tons per year due to the red burnt shale of paleo-fires fires being mistaken for signs of active fires [24]. [ In Xinjiang Province red burnt shale has been dated as forming at intervals over the last 2 million years [38]. [ Nevertheless active ‘wild’ coal fires remain a significant contributor to global warming. Coal fires in China have a voluminous literature; therefore our paper per seeks merely to show something of what can be seen of the fires by using Google Earth.

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Coal fires in Mongolia

Coal fires in Mongolia have been, and remain, common in Jurassic and Cretaceous coals that predominate in most regions. Coal oal fires have hav occurred in the open pits or dumps of Sharin Gol Mine, Maanit Mine, Baganuur Mine, Shivee Ovoo Mine, Chandaltal Mine and Aduunchuluun Mine plus unconfirmed reports elsewhere. A risk analysis is needed,, bearing in mind the many new mines that are currently planned to open soon in similar strata, and a few are likely to be of very large size while some intend to be hybrid mines nes producing coal and oil shale so increasing the risk of ‘difficult’ fires.

Figure 23. red shale at Maanit Coa Coal Mine The red-orange orange colour on the left are bricks produced in a coal coalfired brick kiln at the Maanit Brickworks by heating carbonaceous pyritic shales from the Maanit Coal Mine in Tov aimag. The mine is the open pit in the centre right where orange tinged areas are tell-tales tales of coal fires. (image: Google Earth)

Figure 21. black smoke from small coal mines Black smoke belching from a small coal mine near Wuda in Inner Mongolia. (image: Google Earth)

Black smoke belching from coal mines min is rather uncommon; for it indicates only partial combustion of the coal has occurred with huge concentrations of carbon particles flung into the atmosphere. Black smoke is more typical of fires in oil shale, oilfields and in the petrochemical industry. However coal seams can be intimately associated with oil shale, as in large parts of Mongolia. Should a coal seam and its overlying oil shale catch fire then a ratchet effect occurs whereby each fire feeds the other and containment is exceptionally difficult difficult.

Figure 22. white smoke from small coal mines White smoke belching from small coal mines near nea Wuda in Inner Mongolia. (image: Google Earth)

Figure 24. red shale at Chandaltal Coal Mine A coal dump at Chandaltal Coal Mine east of Ulaanbaatar. The dump caught fire years ago and is now an unsalable mass of red ash. Some coal remains and attracts diggers d as shown by the convergent tracks. (image: Google Earth)

We are unaware of any coal fires at new mines in the South Gobi and western Mongolia. However it is likely that major coal fires will occur as large natural coal fires have destroyed much Permian coal at Tavan Tolgoi in prehistoric times producing burnt rock 50 metres thick, and natural atural burnt shale has also been reported from Nariin Sukhait and Ukhaa Khudag coal areas [19].

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Risk of acid mine drainage

To form coal,, plant material generally has to be preserved by anaerobic (oxygen-less) less) conditions as found in most waterlogged swampss and bogs. Such peaty environments not only preserve coal-forming forming materials, but are also ideal for sulphur bacteria. As a result, coal is often found in association with biogenic pyrite (iron disulphide FeS2). Pyrite is a very stable mineral unless and until ntil it is brought into contact with aerobic (oxygen (oxygen-rich) groundwater.. Then the pyrite is rapidly decomposed to yellowish-brown brown iron oxides (rust, ochre) and the sulphur is released as acids causing water to have very low pH. Once pyrite has decomposed then hen ‘acid mine drainage’ (AMD) occurs, with ochreous acidic water issuing from the he mine mouth, dumps, springs and wells. wells Apart from its orange-brown colour being offensive, the ochre can damage wildlife by clogging the eggs and gills of fish and invertebrates and by retarding photosynthesis by aquatic plants by blotting out the sun. The extremely low pH of AMD eliminates many species of marginal, floating and submerged vegetation and only a restricted number of acid-tolerant species survive. Furthermore the high acidity of AMD renders groundwater water capable of leaching out heavy metals to produce highly toxic water. Acid mine drainage (AMD) is the norm orm for ‘black coal’ mining districts in the British Carboniferous boniferous and orange streams are sometimes visible on Google Earth; Earth while in mainland Europe a feature is the swathe of acidic flooded brown coal open pits that extends from Germany to Czech and Poland [10]. Paradoxically ochre streams are rarely visible in Mongolia or northern China’s coalfields – apart from the vicinity of Wuguantun where orange streams are common. We suggest that the scarcity of ochre streams is due to arid regions having alkaline ‘calcrete’ soils capable of buffering acidic mine waters. In contrast many of the coalfields lds of Europe have topsoil rich in humic acids from partly decayed lush vegetation and have enough rainfall to leach carbonates from the subsoil. If confirmed, then this can explain why AMD can have a marked effect in Europe but little discernable effect in the Gobi.

Figure 25. ochre water flowing from a coal mine Yellowish-brown brown water downstream of a small coal mine in north China. (image: Google Earth)

Figure 26. ochre water flowing from a coal mine View of the surface layout of a medium medium-sided underground coal mine in northern China. A stream of yellowish ellowish-brown ochre water is issuing as ‘acid mine drainage’. (image: Google Earth)

We are unaware of any remedial treatment of AMD in Chinese coalfields. An example from the UK Lancashire Coalfield is shown below [21].

Figure 27. treatment of AMD in the UK Treatment ponds for neutralising AMD and removing precipitated ochre from the 400-old old coal mines in Haigh Plantations, Wigan. (image: Google Earth)

Acidic ochreous water can issue from coal mines for centuries as seen at Worsley near Manchester [21].

Figure 28. 500 years of AMD from a UK coal mine AMD from ancient coal mines discolouring the Bridgewater Canal at Worsley near Manchester. The orange colour is now part of the tourism character of the village. (image: Google Earth)

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Options for waste transport

With exceptions such as parts of the Gobi, open pit coal mines have substantial amounts of waste that has to be stripped and dumped. The waste is two-fold fold: a) overburden material that is younger than the coal strata and poses no risk of dump fires due to a general absence of coaly material, e.g. lateritic clays, loess silt, river gravel. b) more variable waste material from between the coal seams, such as carbonaceous shale, sandstones, seatearth clays, unsellable poor quality coal coal, and thin unrecoverable coal. The presence of much carbon and pyrite renders these dumps vulnerable to coal fires from spontaneous combustion combustion; and to the triggering of acid mine drainage AMD. Dump trucks and tippler trucks are the current norms in Mongolia a and China for transport of material from open pits to waste dumps – not only for coal mines but also for hardrock gold, placer gold, iron and copper. The main options for transporting waste to dumps dump are: i) dump trucks, ii) tippler trucks, iii) dozers, iv) scrapers, v) conveyors, vi) overhead cableways, vii) draglines, or viii) railways. i) Dump trucks offer many advantages, notably: flexibility, versatility, readily available spares, ease of finance, ease of subcontracting and overall simplicity for management.

Figure 30. conveyors in German brown coal mine Integration of large-scale scale stripping machines with conveyor systems has eliminated any need for trucks. Mirash Mine. Mine (image: Bernd Braeutigam from Google Earth)

vi)

Draglines are the norm for stripping and dumping material from large open pit coal mines in Mongolia notably: Sharin Gol, Baganuur and Shivee Ovoo. All are highly efficient ‘walking draglines’ but hampered by having too short a reach and therefore costs escalate as dumps are put on reserves, demanding double or treble handling or sterilization of reserves.

Figure 29. dump trucks in a placer mine Dump trucks at the Ar Naimgan Mine of Altan Dornod Mongol Ltd. (photo: Robin Grayson)

ii)

Tippler trucks are popular for while not as efficient for short-haul to dumps, they offer the flexibility of being able to also transport coal on dirt roads to railheads or direct by hard roads to end-users. iii) Dozers are useful in stripping and for grading dumps, but are not cost-effective effective for pushing material long distances [22]. iv) Scrapers are rarely seen for, although again useful in stripping and for grading dumps, these machines are designed for shorted haul than dump trucks or tippler trucks [22]. v) Conveyors are rarely used for removal of waste from open pit waste to dumps, in spite of their heir low energy costs, low manning levels and ability to span soft ground, water, slopes and irregular areas. For these reasons, long-distance distance conveyors are a feature of dozens of large brown coal open pit mines in Germany, Czech, Poland and Kosovo and have hav completely eliminated trucks. Stacker tacker conveyors are increasingly common in Mongolia’s placer mines and have begun to replace fleets of dozers and trucks for the transport of waste by virtue of the much lower capital and operating costs, and faster better rehabilitation [22].

Figure 31. draglines in Mongolian coal mines Insufficient reach of draglines is apparent: apparent TOP – Sharin Gol Coal Mine (photo: Chimed Chimed-Erdene) BOTTOM – Shivee Ovoo Coal Mine (photo photo: Robin Grayson)

vii) Railways were the norm in China and Mongolia for hauling waste from large open-pit open coal mines to dumps. Powerful coal-fired fired locomotives kept energy costs low and predictable. Sometimes the tracks to the dumps are of mainline gauge, enabling coal to also be transported directly from the mine face to the main railway network. Some mines such as Sandaoling are switching to diesel haulage, but others like Sharin Gol have scrapped rail in favour of o trucks and draglines for hauling waste, while still using rail for shifting coal. Rail generatess far less spillages and dust than road haulage of waste, waste and throughout the mine-life the waste dumps are essentially ‘level top’, albeit ribbed. Road oad haulage creates irregular dumps more prone to dust generation and more challenging to rehabilitate. Rail also is able to respond effectively to pit fires whereas road trucking has to halt.

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Options for coal output

Large coal mines require high capacity output to be profitable as coal is a bulk mineral commodity of low unit value. Output is complicated by having to respond to seasonal peaks and troughs in demand. Indeed in winter Ulaanbaatar is the world’s coldest capital and has an acute peak demand for coal for heating and power generation. In response the larger coal mines (Baganuur, Shivee Ovoo, Sharin Gol etc) try to build up summer stockpiles of coal when demand is low, but this strategy has three inescapable weaknesses: a) working capital is often exhausted in financing the growth of the summer stockpile; b) stockpiling risks spontaneous combustion which not only has health, safety and environmental issues but also destroys coal, cuts essential coal supplies to winter clients, and drains the mine’s cash-flow; and c) delivering peak amounts in winter puts a serious strain on the capacity of track, wagons and rolling stock of the Ulaanbaatar Railway Company. These factors exert strain on the large coal mines by increasing capital expenditure (i.e. more equipment) and demanding more working capital (i.e. more stockpiling), compounded by the Government’s desire to hold down coal price contracts for generating electricity and district heating. The large mines are therefore ill-equipped to fully meet the winter peak for coal. Small wintertime licensed coal mines operated by private companies for the winter peak, specialise in supplying coal to half of the population who live in gers (felt tents), and to facilities such as brickworks, schools and industries that have seasonal heating plants. Small private licensed mines require little capital expenditure on equipment and can be mothballed in summer when its laid-off workers can find seasonal work in other industries such as summer-only placer gold mining.

Small wintertime unlicensed coal mines operated by informal ‘ninjas’ play an essential role in keeping Ulaanbaatar supplied with coal for heating during winter. About 1,100 coal ninjas operate over 100 unlicensed mines in wintertime at Nailakh, a satellite of Ulaanbaatar. While there are serious safety, health, environmental and child labour issues [4, 32], our field observations show that since about 1995 their seasonal activity has filled a serious fuel gap for over many thousands of households in Ulaanbaatar’s ger areas that the formal mines have difficulty in supplying. The alternative would be for an acceleration of the already serious deforestation of the Ulaanbaatar region by cutting trees for faggots.

Figure 33. adits of informal coal mines A string of 20+ adits in a seam at Nailakh, Ulaanbaatar. The coal seam is dipping south (bottom). (image: Google Earth)

Figure 34. hauling coal at an informal adit An empty home-made tub being dragged back underground for again filling with coal and then winching back to the surface. Ninja ‘winter-only’ mine at Nailakh. (photo: Robin Grayson)

Figure 32. sells coal in the winter, gold in summer Unique mine near Zaamar. It produces coal in the winter, and then switches to washing the overlying Neogene gravels for summer to produce placer gold. (photo: Professor Minjin)

Small all-year-round licensed coal mines operated by private companies are scattered nationwide, serving customers who are remote from rail and too far from the large mines for trucking to be affordable.

Figure 35. head-frame of informal ‘ninja’ shaft Preparing a new head-frame over a vertical shaft ready for winter mining at Nailakh near Ulaanbaatar. (photo: Robin Grayson)

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Coal transport – rail option

Exceptionally large coal mines require exceptionally high capacity transport facilities.. Rail is the preferred option, fed by stockpiles able to tolerate rail interruptions and respond to seasonal peaks and troughs ghs in demand. demand

Large coal mines still demand high capacity rail transport facilities fed by stockpiles capable of responding to seasonal peaks and troughs ghs in demand demand.

Figure 38. efficient loading of coal trains train Rail wagons being loaded from all-weather weather overhead conveyors at the Shivee Ovoo Coal Mine. (photo: Chimed-Erdene Chimed Baatar) Figure 36. most efficient loading of coal trains train A new facility able of swiftly loading merry-go-round round trains with Mongolian coal close to the China border. Yet the lack of a windwind break may make this otherwise neat facility acutely vulnerable to liberating excessive coal dust over a wide area. (photo: website of South Gobi Coal Inc – www.southgobi.com )

However the sheer size of the rail loading facilities, and the large mine-site site stockpile necessary to consistently supply them, can cause significant impacts. A particular concern is the excessive release of coal dust from tthe large coal stockpiles, the risk of coal fires in the stockpiles, and dust and multi-tracking tracking if road trucks supply the stockpile. This is considerably aggravated if road trucks also transport a proportion of the coal from the stockpile to customers, as is possible south of Narin Sukhait.

Figure 39. efficient loading of coal trains train A dump truck is dumping coall onto a rail-side rail stockpile, managed by a red conveyor-crane. crane. Coal dust is blowing from the dump truck and stockpile. (photo: Chimed-Erdene Erdene Baatar)

However the unsustainable low coal price set by Government for supply to power plants has often deterred investing in modern rail loading facilities. At Sharin Gol Coal Mine the rail loading facilities are degraded, inefficient and expensive to operate.

Figure 40. inefficient loading of coal trains train 60-ton rail wagons being loaded at Sharin Gol Coal Mine by a large electric face shovel.. (photo: Robin Grayson)

MAK Eldev Coal Mine’s rail-side side stockpile is poorly designed affecting a wide area with coal dust, and coal loading facilities are inefficient and expensive to operate.

Figure 37. most efficient loading of coal trains train A new large-scale scale coal stockpile south of Nariin Sukhait at anew railhead inside China. After only a couple of years in operation, the ground to the SE of the facility is now covered cove in a thick carpet of coal dust for more than 3km, km, and a thin plume is apparent for a further 7km downwind. (image: Google Earth)

Figure 41. inefficient loading of coal trains train 60-ton ton rail wagons being loaded from the rail rail-side stockpile of the Eldev Mine by a front-end loader.. (photo: Chimed-Erdene Baatar)

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Issues at rail loading sites

Coal is hauled by 50-ton road trucks along a 23km dirt road from MAK’s Eldev Coal Mine to its stockpile alongside the Trans-Mongolian Railway at a settlement known as Railway Station #25. From the stockpile, the coal is loaded inefficiently into 60-ton rail trucks by a front-end loader. Coal is delivered by rail to Erdenet Copper Mine, Khutul Cement Factory, Ulaanbaatar Power Plant #2 and some is perhaps destined for export to Erlian city in China.

Although full output commenced at the Eldev Mine Coal as recently as 2005, Google Earth shows that by 8th June 2004 its impact had become considerable at the railhead, and that by 29th March 2007 this impact had become excessive, causing a nuisance from coal dust over a wide area. Meanwhile, several industries had expanded in the immediate vicinity of the railhead – rail ballast mining, chemical grade fluorspar and gypsum. Coal dust is not appropriate next to fluorspar or gypsum processing.

Figure 42. rail loading facility - 8th June 2004 The coal stock-pile of Eldev Coal Mine. (image: Google Earth)

Figure 44. rail loading facility - 28th March 2007 The same view 32 months later. (image: Google Earth)

Figure 43. rail loading facility - 8th June 2004 Closer view of the stockpile with open land still present on most sides. The mine has only been operating for a short time but coal dust covers much ground to the south-east – see bottom right. The haul road from MAK’s Eldev Mine is in the top corner and reaches the stockpile via a level crossing. (image: Google Earth)

Figure 45. rail loading facility - 28th March 2007 Closer view with the stockpile now much enlarged and hemmed in by new mining developments – A) rapid expansion of industrial mining for railway ballast; B) mine camp of a new gypsum mine; c) fluorspar upgrading plant; D) fluorspar rail loading area. The coal dust now covers a much larger area. (image: Google Earth)

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Coal transport – road option

Exceptionally large coal mines require exceptionally high capacity transport facilities. Road trucks are an option are most cost-effectively effectively fed directly from the floor f of an open pit and delivered directly to customers. Exceptionally large fleets of road trucks are essential for the round trips. Compared to rail, the extra burden of fuel and staff is severe – for instance a single train with a 44 man crew might haul 100x60 ton rail trucks, matched by 100 road trucks and at least 100 drivers.

Figure 49. road trucks being loaded on mine floor 12-wheel 60-ton ton road trucks being filled by a hydraulic excavator on the pit floor of the Nariin Sukhait Mine in the South Gobi. (photo: website of Ivanhoe Mines – www.ivanhoe-mines.com) www.ivanhoe Figure 46. road trucks in large fleets Part of a fleet of new 12-wheel 60-ton ton road trucks at an exceptionally large coal mine in the South Gobi of Mongolia. (photo: website of South Gobi Coal Inc – www.southgobi.com) www.southgobi.com

A fleet of road trucks is more difficult to schedule than a coal train. An even flow of road trucks is frustrated by variations in travel-time due to variations ions in speed and mechanical trouble, and due to chaos theory when vehicles attempt to travel nose-to-tail. In addition the haul roads on a pit floor are often so narrow that a single vehicle can cause a massive tailback.

Figure 50. road trucks being loaded on mine floor 12-wheel 60-ton ton road trucks being filled by front front-end loaders on the floor of the Nariin Sukhait Mine in the South Gobi. These trucks are high-sided, sided, suitable for coal transport. (photo: website of South Gobi Coal Inc- – www.southgobi.com) www.southgobi.com

Figure 47. queue of coal trucks at mine entrance ent Coal trucks delayed at the entrance to the Nariin Sukhaait Coal Mine in the South Gobi of Mongolia. (image: Google Earth)

Attaining a steady flow of road trucks down a haul road onto a pit floor is not easy,, especially in snowstorms, dust-storms, hailstorms, ailstorms, cloudbursts and high winds. Trucks may become boggled down, lose traction, slide into one another or topple.

Figure 51. traffic jam of trucks on mine floor TOP – Nariin Sukhait Mine seems to be shadow of no interest. BOTTOM – adjusting with Picture Manager reveals the mine min floor to be packed with coal trucks. (image: Google Earth)

Figure 48. road trucks descending to pit floor A convoy of Chinese trailer-trucks trucks struggling to descend onto the floor of the Nariin Sukhait Mine. The trucks are robust, but not designed for this demanding task. (photo: website of Ivanhoe Mines – www.ivanhoe-mines.com)

Figure 52. small truck matched to small adit A small truck reversed into the adit of a small private licensed coal mine at Nailakh. Loading of coal is achieved easily even in an outside air temperature was -40C. (photo: photo: Robin Grayson Grayson)

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Coal haul roads from mines

Exceptionally large coal mines using road haulage generate exceptionally large volumes of truck traffic. This demands as a minimum a well-designed haul road plus traffic management measures to reduce bunching and prevent traffic jams. Traffic jams may arise at the mine exit, especially if gradients are steep or if there is a delay at a weighbridge.

The glowing grey carpet associated with haul roads can be traced for at least 30km from large coal mines in the Gobi Desert to the vicinity of the China border.

Figure 53. traffic jam of coal trucks at mine exit Coal trucks struggling in a queue at the exit of the Nariin Sukhaait Coal Mine in the South Gobi of Mongolia. (image: Google Earth)

Coal trucks are easy to see with Google Earth when they are on haul roads on the dark grey desert gravels of the Gobi. The constant stream of heavy trucks soon creates a bright pale grey carpet on both sides of the haul road where a ‘hybrid dust’ has been deposited consisting of fine black coal dust plus fine white silica-rich dust. The coal dust originates from gentle excursions from the top of the trucks plus coal dust cast from the wheels, chassis and bodywork of each truck. The silica-rich dust is due to the vortex and windshear associated with every truck, especially if the trucks are travelling fast or nose-to-tail.

Figure 54. coal trucks on a glowing grey carpet Coal trucks on a haul road south of Nariin Sukhait coal mines. The haul road is well-built but both sides have a bright pale grey carpet of hybrid dust. The glow is stronger and wider to the east (left) due to the prevailing wind direction. (image: Google Earth)

Figure 55. coal trucks on a glowing grey carpet A 30km stretch of a coal haul road from Nariin Sukhait (top left) trending SSE towards the China border. The coal dust content of the hybrid dust seems to fade with distance causing the hybrid dust to brighten after 20 to 30 kilometres. (image: Google Earth)

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Haul road issue – coal spills

Issues associated with coal haul roads are plainly visible in China, and more recently in Mongolia. Issues include: multi-tracking, coal spillages, coal dust excursions and silica-rich dust generation. In addition, while traffic jams may seem to be solely a financial concern due to excessive delays, it is also likely that traffic jams of trucks on mine floors will cause poor air quality for truck drivers and miners alike. From the trucks the release of exhaust fumes and diesel fumes will supplement the sulphurous fumes, coal fire fumes, coal dust and silica dust typical of mine floors. When haul roads are non-existent, or when used over a period of years, then severe ground contamination may accrue from the shedding of coal dust and fragments.

Figure 58. long-distance haul road A convoy of 11 coal trucks from Mongolia travelling SE towards Linhe in China. The well-engineered dirt road as yet has few coal spills and is attracting non-coal traffic. (image: Google Earth)

We have traced a trail of coal spillages from Nariin Sukhait across the border into China for a total of 200 kilometres, with over 100 coal spills detected. This has occurred in only a few years and before the truck traffic has peaked. It suggests that the impact of coal spillages on the desert floor is destined to increase considerably.

Figure 56. haul road with large coal losses A haul road for trucking coal about 15km from mines to a power plant in Laoshidan, China. The road is irregular, causing trucks to spill coal as dust and lumps. (image: 5th Oct 2006 - Google Earth)

Figure 59. trails of coal spillages far into China A trail of coal spills tracked from Nariin Sukhaait Coal Mine across the border splitting SW and SE in China. (image: Google Earth)

Figure 57. haul roads with coal losses A network of haul roads for trucking coal to Qi Ketaicun and neighbouring small towns in eastern China. (image: Google Earth)

Figure 60. trails of coal spillages far inside China The 100th coal spill tracked SW into China. (image: Google Earth)

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Haul road issue – multi-tracks

Mongolia’s dirt roads are notorious for becoming multi-track, particularly as few receive proper maintenance. Usually the most severe multi-track is between towns but can peak with mining activity.

Figure 61. multi-tracking by coal trucks Multi-track exceeding 100-metre width by trucks off the haul road between Narin Sukhait and China. (image: Google Earth)

Figure 64. multi-tracking by coal trucks Multi-track peaking at 150-metre width by coal trucks converging on a ford east of Nariin Sukhait. The brightest tracks are the most recent. (image: Google Earth)

Figure 62. multi-tracking by coal trucks Multi-track peaking at 500-metre width by trucks converging on a ford between Narin Sukhait and China. (image: Google Earth)

Figure 65. multi-tracking by coal trucks Multi-track peaking at 750-metre width by trucks using the full width of a valley south of Baruun Naran from Tavan Tolgoi, and the route is long-established. (image: Google Earth)

Figure 63. multi-tracking by coal trucks Multi-track peaking at 400-metre width by trucks on a small hill east of Eldev’s well-engineered haul road. Many coal spills are visible due to trucks struggling on the hill. (image: Google Earth)

Multi-tracking is so blatant that truck routes, haul road construction and environmental management measures to prevent multi-tracking are ineffective in Mongolian Environmental Impact Assessments (EIAs). This merits scrutiny and some research has been published on natural re-vegetating of multi-tracks in the Gobi [27]. Multi-tracking often damages a larger surface area than the actual mine and its dumps.

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23. Coal-burning power plants in Ulaanbaatar Ulaanbaatar has three main coal-burning power plants, all combined heat and power plants, and known as ‘Thermal and Electrical Stations’ TES #2, TES #3 and TES #4. The three are clearly visible on a time series of highdefinition Google Earth. Also visible is the original TES #1 which has been disused and derelict for many years and is an issue of concern regarding contamination.

Figure 66. coal stockpile of Ulaanbaatar TES #2 Coal is delivered to the stockpile via a short spur line from the Trans-Mongolian Railway. (image: Google Earth)

Ulaanbaatar is the world’s coldest capital city in winter when its air quality plummets due to thermal inversion over the valley and air pollution from coal fires. Half the residents live in ger districts and every ger has a central stove fuelled by coal or sometimes by wood. The coal is lump coal and is mostly from about ten licensed and 100 unlicensed small seasonal mines at Nailakh [32], the coal being delivered in small trucks. In contrast the power stations use coal delivered by rail from Baganuur and Shivee Ovoo coal mines, and at the power stations it is blended and pulverized. According to Dr. Badarch and colleagues [5] if coal cleaning facilities operated at Baganuur and Shivee Ovoo then the calorific content would be boosted before delivery to TES #4. This would save 134,000 tons of coal a year, cut the work of the electrostatic precipitators in removing ash, conserve scarce space in the PFA settling ponds, cut air pollution significantly in Ulaanbaatar and reduce rail congestion. All Mongolia’s industrial towns endure low air quality in winter, and most have thermal inversions with various degrees of smog. Sharin Gol sometimes has spectacular fogs that roll in from the hills that ring it, the fog soon turning to smog from carbon and ash liberated by domestic fires and the thermal plant of the coal mine.

Figure 67. coal stockpile of Ulaanbaatar TES #4 The shadow of the 500m tall stack points at the stockpile and train-loads of coal are in the siding. (image: Google Earth)

Figure 71. thermal inversion over Sharin Gol Cold dense air off the hills fills the town with white fog that becomes smog due to smoke from domestic coal fires and the mine’s power station. (photo: Chimed-Erdene Baatar) Figure 68. Ulaanbaatar TES #2 and TES #4 The short stack of #2 partly conceals the 250m tall stack of #4. Heating pipes supply the city. (photo: Chimed-Erdene Baatar)

Figure 72. dust plume of Sharin Gol power plant A dense plume of hot vapour and smoke rising vertically then forming a sub-horizontal layer. (photo: Chimed-Erdene Baatar)

Figure 69. Ulaanbaatar TES #4 ABOVE – small plumes from the cooling tower and smoke stack. BELOW – large plumes in cold weather. (images: Google Earth)

Figure 70. thermal inversion over Ulaanbaatar Emissions of vapour and dust from TES #2, TES #3 and TES #4 contributing to poor air quality. (photo: Chimed-Erdene Baatar)

A new 400-500mW Thermal Electricity Station is planned for the east side Ulaanbaatar [6]. This may make Ulaanbaatar’s air quality worse, deplete the city’s underground water supply, obstruct the emergence of a healthy competitive capital and strain the hairpin rail bottleneck of the eastern approach to the city. We favour a bolder solution, to close all but one of the power-plants and bring power to the city by a stronger national electricity grid from new distant coal-burning power stations. Then the western half of the city could be developed for thousands of jobs, for instance as a rail-rail hub between the Trans-Mongolian railway and a standard gauge line to China via Tavan Tolgoi and Oyu Tolgoi.

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24. Pulverised fuel ash (PFA) in Ulaanbaatar

25. PFA and radon gas in Ulaanbaatar

Pulverised fuel ash (PFA) is normal waste from coalburning power stations and is settled out in lagoons.

All coal is very slightly radioactive but rarely sufficient to affect human health. However Mongolia’s coal basins have sediment-associated uranium occurrences and some may prove to be world-class U deposits. For instance the Geofund records U occurrences close to some coal mines, notably Shivee Ovoo Coal Mine [14] which is one of Ulaanbaatar’s main suppliers of power station coal. A risk may arise if power stations burn coal that has above-normal radioactivity. We believe this is likely to be the case for power stations in the capital. When such coal is burned most of its radioactive traces remain locked in the residual ash. Hence ash is slightly more radioactive than the coal it came from [3, 20]. The risk is not from ash discharged as smoke to the atmosphere via the power station’s stack. Although this contributes to Ulaanbaatar’s poor air quality in winter, ‘dilute and disperse’ of the airborne ash will render its already low radioactivity extremely low indeed. The risk is from PFA-cement blocks incorporated into interior walls of thousands of new buildings in Ulaanbaatar. Such buildings are double glazed, insulated and centrally heated in winter, encouraging traces of radon escaping from the PFA-cement blocks to accumulate in rooms and perhaps exceed international safety norms.

Figure 73. slurry of PFA arriving from TES #3 Being derived from pulverized coal, the ash is easy to transport to the lagoon by pipeline. (photo: Chimed-Erdene Baatar)

Figure 74. PFA settling lagoons for TES #4 Several lagoons are required to enable periodic clearing out of the settled pulverised fuel ash (PFA). (image: Google Earth)

PFA is strongly alkaline and often has high levels of heavy metals. Ideally PFA lagoons should be sited away from water courses [23] and sealed from aquifers. Unfortunately all the PFA lagoons in Ulaanbaatar are sited above the aquifer that is the city’s sole supply of water, while the PFA lagoons of TES #3 are next to the main channel of the Tuul River.

Figure 75. PFA settling lagoons for TES #3 The lagoons are well-designed but are so close to the Tuul River that a major pollution event is possible. (image: Google Earth)

To minimise ash being vented into the sky, as much PFA as possible is removed by electrostatic dust precipitators and piped as slurry to settling lagoons where it settles out. The PFA has an economic value, being sold to local makers of PFA-cement blocks who sell them in huge quantities to Ulaanbaatar’s construction industry.

Figure 76. building blocks being made from PFA One of many small factories making building blocks from PFA near Ulaanbaatar’s power stations. (photo: Robin Grayson)

The risk to human health of radon in buildings has become better understood since 1996 when the World Health Organisation (WHO) recommended a maximum exposure of 1,000 Becquerel’s/m3. In September 2009 the WHO slashed the recommended maximum level tenfold to 100 Becquerel’s/m3 [37] and presented evidence that radon exposure causes in the range of 3-14% of all lung cancers. The WHO now advises that if a country cannot meet the new standard, levels should not exceed 300 Becquerel’s/m3, noting that the risk of lung cancer rises 16% per 100 Becquerel’s. The task now is to do radon assessments of thousands of houses and apartments in Ulaanbaatar. Mongolian scientists possess the know-how [13], but funding is weak although preliminary studies have been published [18]. Some tests have already been made on the soils around TES #4 and on the coals it uses [7, 8, 9]. We suggest a special risk may exist for caretakers and their families in gers and sheds constructed on ground covered in PFA in fenced yards of PFA processors. The WHO claims that radon exposure adds to the risk of lung cancer from cigarette smoke. In highly insulated gers with radon entering from PFA soil, the risk of lung cancer among smokers and passive inhalers is apparent.

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Time series on Google Earth

Since early 2009 the latest free update of Google Earth includes a button to display a time series of old and new high-definition images one-by-one. one. As yet only about a sixth of Mongolia has any high-definition definition Google Earth and within that there are few time series. The potential is considerable, as shown by comparing the images below. below

A good example of a time series is Ulaanbaatar’s first coal burning power plant known as TES #1 #1, for many years a derelict ruin. The time series confirms that nothing has been done and the dereliction liction remains.

Figure 80.

Figure 77. informal coal mines – 11th Nov 2001 A string of 20+ adits in a seam at Nailakh, Ulaanbaatar. The coal seam is dipping south-west. west. (image: Google Earth)

UB Power Station #1 # - 18th Oct 2007

Figure 80.

UB Power Station #1 – 14th Apr 2007

Figure 81.

UB Power Station #1 -31 - st Mar 2006

Figure 82.

UB Power Station #1 – 20th Oct 2005

Figure 78. informal coal mines – 25th Feb 2007 Six yearss later the 2001 adits have been abandoned and two new strings of adits are active to the north. (image: Google Earth)

Figure 79. informal coal mines – 25th Feb 2007 Each year there are deaths of informal miners at Nailakh near Ulaanbaatar (photo: Mongol Messenger newspaper).

Figure 83. UB Power Station #1 – 22nd Oct 2004 Example of a time series. (images: Google Earth).

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Coal seams on Google Earth

Mongolia has perhaps a hundred coal basins of Carboniferous, Permian, Jurassic and Cretaceous age [15, [ 17]. We find Google Earth of immense value in studying them and clarifying the socio-environmental environmental issues [[16]. An example is the Baruun Naran Coalfield of Late Permian age, a south-westerly westerly extension of the Tavan Tolgoi Coalfield which is Asia’s largest deposit of virtually un-mined high-quality quality bituminous coal and coking coal. A 1.5km wide belt of low ground in a hilly district delineates the Baruun Naran Coalfield on Google Earth..

Figure 84. landform of Baruun Naran Coalfield The relatively smooth low topography of the coalfield contrasts sharply with the rugged hilly country. (image: Google Earth)

Figure 87. geophysical and geological maps TOP – geophysical survey of part of the coalfield. BOTTOM – geological interpretation of the geophysical survey. (images: website of QGX Ltd – www.qgxgold.com) www.qgxgold.com

Figure 85. Soviet geological map of Baruun Naran The Soviet geological map is good, but can be enhanced using high-definition Google Earth. (map: www.qgxgold.com) www.qgxgold.com

Figure 86. oblique view of Baruun Naran Regularly spaced prospecting trenches showing coal discoveries. (image: Google Earth).

Figure 88. coal strata on Google Earth TOP – exploration trenches; note the black streaks of coal. BOTTOM – enhanced image showing coal strata as a series of sharp V shapes pointing ENE. (images: images: Google Earth)

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Coal briquettes in China

Coal briquettes are made either from unsellable coal fragments or from crushing inferior ‘stone coal’ that has high clay content. The powdered material is mixed with a binder such as clay or cement and may be mixed with oil or other calorific supplements. After squeezing in a mould and dried the resultant briquette is a valuable source of fuel for heating homes, buildings and light industries. Artisanal and small-scale coal briquette factories are found throughout China but are unusual in Mongolia. Such factories are prominent on Google Earth due to the crushed coal carpeting the ground. The largest group of such factories detected on Google Earth are clustered along a 60-kilometre ribbon extending from the Beijing district border through Tumu, Hualiali County to Xuanhua.

Figure 89. coal briquette yards for 60 kilometres Several hundred factories engaged in briquette making and coal sales stretching WNW from Beijing. (images: Google Earth)

While coal briquettes are usually safe, acute health issues can arise. The coal may have very high levels of fluorine that exceeds the safety threshold of 190mg F/kg coal which gives a scientific basis for ascertaining coalburning endemic fluorosis-affected areas and potential threaten areas [28]. Such briquettes are one cause of fluorosis in China [36]. Even if the coal has low fluorine content, the clay used as binder to make the coal briquette may have very high fluorine levels, and this is a major cause of fluorosis in China [39]. In some regions, coal is rich in arsenic and such briquettes are one cause of arsenism in China [29].

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Discussion

Coal is of China’s largest industries and has many serious environmental, social and health issues, some affecting the entire planet by global warming. Mongolia’s coal industry is in its infancy and is undergoing explosive growth. Mongolian society has yet to come to terms with the environmental, social and health issues that will arise, and Mongolian policy makers have little time to gain experience of how to respond. Our study draws attention to the following issues that seem particularly relevant to Mongolia: 1: Coal fires – the biggest environmental risk of Mongolia’s coal rush is of a series of coal fires that are exceptionally large and beyond control. Some may have a global impact due to the exceptional size of the coal reserves that might burn. Has a risk assessment been made for coal fires been made for each coal mine specifying how the Government and mine operators can respond quickly and decisively? 2: Stability of pit walls – we have identified a 5km long partial collapse of an open pit coal mine in China. Have sufficient geotechnical tests and precautions been taken to minimise this risk in Mongolia’s large new coal mines? 3: Dust – extreme dust is expected when using bulldozers, trucks and scrapers in a desert, against which dust suppression measures are largely futile. Dust causes serious health problems such as silicosis and eye injuries as well as damaging grazing land, reducing the value of fleeces and rending sheep intestines unsellable as casings. Has the option of ‘rail only’ for waste haulage and coal haulage been properly considered and fully-costed as a simple ‘low-dust’ alternative? 4: Acid mine drainage – AMD is a serious problem in coal mines worldwide, but we can find little evidence for it in the desert regions of China and Mongolia. We suggest that the caliche desert alkaline soils are natural buffers that arrest AMD. Is the real risk of AMD far less than in humid regions such as the coalfields of northern Europe? 6: Fluorosis risk #1 – many of Mongolia’s coal basins formed close to hills with large amounts of fluorine, notably fluorspar. As in parts of China [28], we predict some of Mongolia’s virgin coals have unacceptably high fluorine levels. Has sufficient tests of the fluorine content been made for all Mongolia’s new coal mines? 7: Fluorosis risk #2 – fluoride is excessive in some groundwater [28] in China having leached from fluorinerich minerals such as fluorspar. We predict that some of Mongolia’s bricks and coal briquettes have unacceptably high fluorine content. Has sufficient tests been made of the fluorine content for all Mongolia’s new brickworks and coal briquette factories? 8: Cancer risk – some Mongolian coal basins contain potentially world-class sedimentary-type U deposits, and uranium occurrences are documented in the immediate proximity of some coal mines such as Shivee Ovoo. Apart from a mild risk to the coal miners, an increased risk of lung cancer may exist for residents of apartments built from PFA blocks due to the possibility of radon gas. Has sufficient tests been made of the fluorine content of bricks and coal briquettes from Mongolia’s new factories?

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Recommendations

In conclusion, we make the following recommendations to Mongolia’s policy-makers regarding satisfying the transport needs of the country’s rapidly expanding coal sector. Our rationale is to benefit the whole country rather than to merely “solve the problem” of coal transport. Recommendation #1: construct two new railways of standard gauge from Tavan Tolgoi via Oyu Tolgoi to China and from Nariin Sukhait to China. Recommendation #2: ensure both railways are nonexclusive enabling all companies to use rail to export coal, other minerals and for general movement of goods. Outcome:  rail gains more traffic, therefore rail cost falls.  allows all mines, large and small, to export efficiently.  encourages start up of small mines for rail export of industrial minerals such as fluorspar, coltan and mica.  encourages exploration of oilfields in the Gobi.  new rail route for export/import of goods.  for other outcomes, see below. Recommendation #3: a moratorium on using roads to transport minerals, goods, people or livestock to China when the rail routes are available. Outcome:  rail gains more traffic, therefore rail cost falls.  eliminates cross-border hard roads and feeder haul roads.  cuts dust and eliminates multi-tracking.  removes need for ‘truck towns’ next to the border.  better border customs processing without trucks.  better border security without trucks or ‘truck towns’.  cuts impact on protected areas and their buffer zones. Recommendation #4: require large mines to connect to the rail system. Outcome:  rail gains more traffic, therefore rail cost falls.  cut in trucks, reducing dust and multi-tracking.  better border customs processing without trucks. Recommendation #5: require all large mines to use rail spurs to remove waste to dumps. Outcome:  rail gains more traffic, therefore rail cost falls.  less dust in transporting and dumping waste.  better able to deal with coal fires at large coal mines.  minimises expensive imports of fuel. Recommendation #6: investigate extending a standard gauge railway from Tavan Tolgoi to a rail-rail interchange at the western side of Ulaanbaatar. Outcome:  creates a new N-S economic corridor.  better fuel security by giving shorter same-gauge access to imports of fuel via China.  Ulaanbaatar gains fast access to the high-speed rail route to Europe under construction near the border.  thousands of new jobs created in Ulaanbaatar in railways, warehousing, manufacturing and tourism.  western Ulaanbaatar revitalised as a pleasant city.  rail time to China cut in half, allowing Ulaanbaatar to compete with Erlian for cross-border trade.  Mongolia has sovereignty over an international railway.

31.

www.mine.mn

Acknowledgements

This study was made possible by made possible by Eco-Minex International Ltd (EMI) funding many hours late at night on Google Earth. Special thanks are due to the encouragement and logistical support with the fieldwork by staff of the London PLUS-listed Lotus Resources PLC notably Simon Longworth, Henry Tebar and Minjin Batbayar. The authors are pleased to acknowledge the valuable assistance given by many people and organisations over the last few years. Special thanks are due to: Tony Whitten (World Bank); Dr. Baatar Tumenbayar (San Frontier Progress NGO); Les Oldham (Geologist); Michael Priester and Jorgen Hartwig (Projekt-consult gmbH); Bernd Braeutigam (Geologist); Manfred Walle (Mining Engineer); Dr. Peter Appel (Greenland and Denmark Geological Survey GEUS); Tsedeegiin Janchiv (Mining Rescue Service) and members of the Alaska Gold Forum. Special thanks from Robin to Iain Williamson of Wigan Mining College plus Dr. Fred Broadhurst and the late Dr. Michael Eagar of Manchester University for tutoring in coal geology; to Donald Anderson and Tony France for guidance on coal washeries, small mines and ochre; to Rod Ireland for guidance on acid mine drainage from coal mines that are four centuries old, and to all members of the Wigan and District Geological Society for ten years of visits to a vast number of coal seams and coal mines in the Lancashire Coalfield. We express our appreciation to the managers and staff of over a dozen coal companies for access to their mining operations; and to the artisanal coal miners of Nailakh who generously shared their opinions.

32.

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