Geosciences and Mining Journal 2020

GEOSCIENCES AND MINING JOURNAL Series-01

Table of content FOREWORD...... i MESSAGE FROM THE DIRECTOR GENERAL...... ii EDITORIAL...... iii GEOSCIENCE FOR SOCIETY...... 1 GEOLOGY AND MINERAL RESOURCES OF BHUTAN - AN OVERVIEW...... 4 MINERAL EXPLORATION FOR MINING DEVELOPMENT...... 11 LANDSLIDE HAZARD IN BHUTAN...... 14 National Earthquake Monitoring Network...... 19 INTEGRATED GEOPHYSICAL IMAGING TECHNIQUES FOR SLOPE STABILITY STUDY AT CHAPCHA...... 28 REFORMS IN THE MINING SECTOR...... 42 MINING CADASTRE AND ITS INTRODUCTION IN BHUTAN...... 47 VALUE ADDITION OF MINERALS...... 55 THE MIDDLE PATH : STRATEGIZING ENVIRONMENTAL COMPLIANCE IN MINING IN BHUTAN...... 59 Mining Sector at a Glance ...... 65 ABOUT THE CHEMICAL LABORATORY...... 74 4 | GEOSCIENCES AND MINING JOURNAL FOREWORD The Economic Development Policy 2016 outlines economic roadmap of the country and identifies mining sector as one of the core growth areas and five economic jewels of Bhutan. With Bhutan’s graduation from Least Developed Countries (LDC) in 2023, this sector is expected to play an important role to realize self-economic reliance. However, the mining industry in the country is relatively underdeveloped with contribution of only 4.22 percent to the GDP in 2017.

The Article 1 (12) of the Constitution of the Kingdom of Bhutan enshrines the ownership of mineral resources to the State. It is therefore, critical to develop the mineral resources in a sustainable way by ensuring maximum economic benefits to the State with minimal social and environment impacts.

Mineral resources in Bhutan include industrial minerals, stones, gravel and sand, which are basic inputs for domestic industries and construction sector. The occurrence of the few high-valued metallic mineral resources are also known.

The current information on geology and mineral resources of Bhutan is sparse, largely because the systematic geological and mineral mapping is at an early stage. The potential to discover more mineral resources is relatively high.

Mining brings about huge socio-economic benefits, but at the cost of environment. The adverse impact of mining can be reduced through scientific mining, strong legal frameworks and enforcement, progressive taxation and fiscal regimes, broad-based ownership and benefit sharing.

Further, the geological setting of Bhutan makes the country highly vulnerable to geological hazards like landslides and earthquake. The risks from these geological hazards will increase with the expan- sion of land-use development. The risk can be reduced through enhanced application of geosciences knowledge.

On behalf of the Ministry of Economic Affairs, I, am pleased to introduce “Geoscience and Mining Journal of Bhutan 2019” intended to create awareness on the geosciences and mining mandates of DGM, policy intents, relevant laws on mining and recent developments.

I acknowledge the effort of the DGM in publishing this journal and I am hopeful that this journal and subsequent series will be useful to the government and people of Bhutan in terms of promoting geoscience for meeting the demands of society, sustainable mining and economic development.

(Loknath Sharma) Honb’le Tengye Lyonpo

GEOSCIENCES AND MINING JOURNAL | i MESSAGE FROM THE DIRECTOR GENERAL

It is my pleasure to introduce “Geosciences and Mining Journal of Bhutan 2020”. The journal will provide first-hand information on development in geosciences, mineral resources and mining in Bhutan and highlight the importance of geosciences for sustainable land-use development and reduction of risks associated with geological hazards.

Bhutan lies within one of the most active young tectonic mountain systems, which makes the country highly vulnerable to geological hazards like earthquakes and landslides. The risk associated with geological hazards are likely to increase with increased land-use and climate change.

The systematic geological mapping effort is currently at an early stage and the geological knowledgebase of the country is limited. To attract more investment in exploration and mining, it is important to carry out systematic regional geological surveys using remote sensing, geochemistry, geochronology in conjunction with field mapping. The geological map produced can also be used for civil works, groundwater exploration, geological hazard and risk assessment, and environmental protection.

As most of the infrastructure development works are carried out at subsurface which involves geological uncertainties, it is paramount that geological studies are conducted for safe development and to avoid project delays and cost overruns.

To bring the geosciences at the core of land-use development, it is important to adopt a Geoscience Policy. This policy shall provide the strategies to improve geoscience knowledgebase and integrate application of geosciences in developmental activities.

In order to improve the governance and business environment of the mining sector and to maximize its contribution to the socio-economic development of the economy, the Mineral Development Policy 2017 (MDP) was adopted. The MDP 2017 envisages development of an environmentally friendly and socially responsible mineral industry that contributes to mutually beneficial coexistence with local communities and other industries in pursuit of the overall development philosophy of the country, the Gross National Happiness.

Given its economic potential, the sector is categorized as one of the five economic jewels of Bhutanese economy in the Economic Development Policy 2016 (EDP). In line with the EDP 2016 and MDP 2017, the revision of Mines and Minerals Management Act 1995 is carried out to attract investment by promoting transparency and securing the tenure of the mining lease. Further, prospecting and exploration rights are envisaged for progression to mining lease.

The Department of Geology and Mines is now well positioned to implement the MDP 2017, EDP 2016 and the revised Mines and Minerals Bill. The development of Mines Administration System (MAS), adoption of GIS system in geosciences, real time Earthquake Monitoring System and Geosciences Data- base shall facilitate us to publish Geoscience and Mining Journal on a regular basis.

With best wishes,

Mr. Choiten Wangchuk Director General, DGM ii | GEOSCIENCES AND MINING JOURNAL EDITORIAL

In an effort to disseminate the mandates of Department of Geology and Mines (DGM) with regards to geosciences, mining and mineral information of Bhutan, it’s my pleasure to introduce “Geosciences and Mining Journal of Bhutan 2019” to the readers. This publication will be an annual series.

Editorial Team This publication is first of its kind portraying the roles played by four divisions viz. Earthquake and Geophysics, Geological Survey, Mining, Dr. Dowchu Drukpa Chair and Mineral Development. It is anticipated to create public awareness on recent development, laws, performance of the sector, strategic plans and Mr. Karma Chophel policies. This Journal will also be serving as the much needed platform Member for the Bhutanese professionals, researchers, and academician for publication on earth sciences and mining. Prior to this, the DGM has published Mr. Tashi Tenzin “Bhutan Geology Newsletter” with geo-scientific information and report Member on activities carried out by the department.

Mr. Jampel Gyeltshen Bhutan is located within the active tectonic regime of Himalayan Orogeny Member and fragile geology, where geo-hazards and risks are alarmingly high. It is also vulnerable to climate change. Therefore, importance of application Mr. Kinzang Duba of geosciences to its developmental activities is very critical. Any land use Member development requires insight of geoscientific knowledge to ensure long term stability and suitability, and minimizing economic loss. Additionally, Mr. Nima Yoezar it enhances the optimum use of scarce natural resources and discover po- Member tential natural resources. Ms. Radha D.Sharma Member The National Earthquake Monitoring network for better understanding of seismicity has been installed to help build seismic resilience. Similarly, Mr. Sangay Dendup landslide is another geo-hazard which takes cumulative toll on lives and Member economy. Landslide are investigated and monitored.

Bhutan also has host of minerals resources. Some of the prominent minerals includes coal, dolomite, quartzite, graphite, tungsten gypsum, talc, copper, zinc and limestone, etc. The DGM is mapping and exploring the mineral resources in the country to lease as mines.

The mining sector is undergoing major reform to leverage its contribution to the national economy. Some of the reforms includes enactment of mining law, institutional restructuring and establishment of mining cadastre. Lastly, I would like to express my gratitude to Mr. Javier Aguilar, EGPS Project Task Team Leader for conceptual framework and World Bank for financial support of the Journal.

Best wishes,

Dr. Dowchu Drukpa

GEOSCIENCES AND MINING JOURNAL | iii

GEOSCIENCE FOR SOCIETY Tashi Tenzin1

What is Geoscience? It is more critical for a country like Bhutan that is located within one of the most active, A science of earth that covers study of young and highly deformed Himalayan rocks, minerals, fuels, fossils, groundwa- mountains with a very fragile geological ter, glaciers, geological structures including conditions and steep topography, making their age and the processes responsible for it highly vulnerable to climate change and their formation and modifications including geological hazards. Some common geolog- the geological hazards. ical hazards in Bhutan include earthquake, slope failures or landslides, Glacial Lake Geology defines the beautiful landforms- Outburst Floods (GLOF) and flash floods. mountains and valleys of Bhutan; type of soil on which our flora, fauna and agricul- The consequences of geological hazards ture depend; geo-materials (rocks, minerals, may include loss of lives and properties, gravel, sand, stones) for industry and con- safety and sustainability issues of civil struc- struction; and geological hazards and risks. tures, and significant cost escalation during and after construction, thereby imposing a The Role of Geoscience in huge financial burden to an individual or a nation. Development As a mountainous developing country, in- Our earth is a dynamic and complex system frastructural development and human set- that undergoes continuous evolution and tlements on highly vulnerable slopes are modifications within (e.g. tectonic, radioac- inevitable due to limited flat areas. Further, tivity) and on the surface (e.g. weathering, the risks from geological hazards to people erosion, landslides, denudation etc.) respon- and properties are likely to increase with sible for geological hazards such as earth- (1) climate change, (2) a rise of population, quakes, landslides, flash floods, subsidence, and (3) increased pace of development with slope failures, etc. inadequate geoscientific considerations. In this regard, geoscience will be the key for The geological hazards become more rel- understanding in solving the geological evant when it interacts with human and its hazards and related environment problems activities. Since infrastructures are mostly of the current and future in terms of recog- founded on the earth’s surface, proper un- nizing, assessing the degree of hazard and derstanding of dynamics of earth’s systems risks, and making policy and mitigation rec- has globally become a priority for safe and ommendations. sustainable development and settlements.

1 Tashi Tenzin, Executive Geologist, Department of Geology and Mines, Thimphu, Bhutan. Master of Geoscience, The University of Western Australia. Email: [email protected]

GEOSCIENCES AND MINING JOURNAL | 1 The Role of Geoscience in extracted from earth’s crust. Management of Natural Further, groundwater which is dependent on Resources hydrogeological condition forms an important source of drinking water, sanitation and Food Resources irrigation.

Soil formation and its fertility depend pri- As population and demand for natural re- marily on its source rocks and constituent sources increases, geoscience will not only minerals. Geology is also largely respon- be important to discover and evaluate more sible for hydrogeological conditions that of these resources, but also be important in is essential for crops. Further, geoscience its safe extraction and sustainability. is important in identifying and mapping of mineral-rich rocks that will be used to improve the soil nutrients, pH and soil struc- The Role of Geoscience in tures that are essential for agriculture prac- Environmental Protection tice. The knowledge of geology of an area will be key for sustainable and productive Ecosystems and Biodiversity agriculture development and food security. For instance, a geological map shows dis- The living environment of animals and tribution of rock types that are indicative of plants is dependent on soil and hydrogeo- type of soil and define its suitability for ag- logical conditions, which is primarily de- riculture and treatment required. fined by the geology. For instance, fluctu- ation of moisture content in the soil due to Energy, Mineral and Groundwater change of hydrogeological conditions and Resources geological hazards like landslides, floods, mudflows, and erosion can affect ecosys- Mineral resources and mining are one of tems. Therefore, understanding of subsur- the major drivers of economic growth and face geological processes and its interaction prosperity. From resources such as building with surface is important for understanding stones, aggregates, cement, iron and steels, biosphere. metals used for construction of homes and infrastructures like dams, bridges, Climate Change roads, airports, schools, hospitals, sports facilities, hydropower and energy network, Global climate change is a challenge for telecommunications and ICT networks to the society, indicated by rise in global mean manufacturing of electronics (e.g. mobile surface and ocean temperature, rise in sea phones, televisions, refrigerators etc.) to level, retreat of glaciers, ocean acidifica- jewelry (e.g. diamond, gold, silver, ruby, tion, climate extremes, global water cycle platinum etc.) and transports (e.g. airplane, and rainfall patterns causing global to lo- cars, ships etc.) to almost every items we use cal scale impacts. Geological records have daily and the fuel energy supply required proven to be critical in reconstruction of for running the machineries and vehicles, past climate and CO2 levels. This plays a the energy (hydro-carbon) and mineral pivotal role in understanding present global resources, both abundant and rare, must be climate change and predicting future trend

2 | GEOSCIENCES AND MINING JOURNAL when our earth is experiencing an abnormal conditions and the engineers are expected to change in the climate system. Geoscience embrace the geological knowledge for bet- is therefore expected to play significant ter design and implementations. The public, role in understanding the climate-change at the least, must be able to appreciate the and providing better solutions of adapta- importance of geoscience for meeting their tion and mitigations to reduce the impacts demands and solving challenges that con- of climate change. For example, geoscience front them. Geoscience will serve us better can be important for assessing the risks of if its roles are appreciated, felt and promot- climate change induced geological hazards ed by everyone collectively. like landslides and floods and implementing adaptation and mitigation to reduce risks. References

Waste disposal Geology for Global Development. Geology and Development. Retrieved from http://www. The waste we generate from house, indus- gfgd.org/key-themes try, mines and any activities need a proper Parriaux, A. (2019). Geology Basis for Engi- disposal. Since these wastes may potentially neers Second Edition. Leiden, The Nether- contain toxic contaminants, it can potential- lands: CRC Press/Balkema. ly result in disaster through contamination The Geological Society and European Federa- tion of Geologists. (2015). Geology for Soci- of drinking water source, groundwater, soil ety, European Edition. Retrieved from www. and affect ecosystems. Geoscience is im- geolsoc.org.uk/geology-for-society portant to locate suitable sites for waste disposal to prevent or reduce associated risks to human lives, properties, ecosystem and environment from waste pollutions.

The Need for Team Approach to Find Solutions

The earth is a complex dynamic system capable of providing us resources to fulfil our needs and wants but also challenged with major geological hazards and environmental problems. The challenges increase with the increased interaction between human and geological environment. Geoscience will be crucial in finding solutions to meet societal demands and challenges. No single person or discipline has the know-how to find solutions for these massive demands and complex challenges. It will need the integration of geoscientific knowledge into developmental plans. Geologists are expected to present better understanding on geological

GEOSCIENCES AND MINING JOURNAL | 3 GEOLOGY AND MINERAL RESOURCES OF BHUTAN - AN OVERVIEW Tashi Tenzin 1 and Phuntsho Pelgay2

The Himalayan Orogeny

The Himalayan Orogeny (mountain system) is a typical example of continental to continental collision - a convergent plate boundary that resulted from about 55 million years of collision between the Indian and Eurasian plate (Hodges, 2000; Mukher- jee et al., 2013).

Some 150 million years ago, the Indian plate was a part of Gondwana Superconti- nent along with Australia, Antartica, South America and Africa in the Southern Hemi- sphere, separated from the Eurasian plate by a Tethys Ocean. The Indian plate started to drift northward since 150 million years ago. When the plate began to collide with Eur- asian plate at around 55 million years ago, this marked the closure of Tethys Ocean and the rise of the Himalayas (Figure 1).

Since the plates are of similar density, one Figure 1: Schematic diagram showing the plate could not be subducted under the other drifting timeline of Indian plate (Source: USGS). and therefore, the enormous pressure of the collision could only be relieved by uplifting and deforming the rock mass, forming the Himalayan peaks stretched about 2900 km laterally.

1 Tashi Tenzin, Executive Geologist, Department of Geology and Mines, Thimphu, Bhutan. Master of Geoscience, The University of Western Australia. Email: [email protected] 2 Phuntsho Pelgay, Executive Geologist, Department of Geology and Mines, Thimphu, Bhutan. Master of Earth Sciences, The University of Melbourne. Email: [email protected]

4 | GEOSCIENCES AND MINING JOURNAL Architecture of the Himalayas continued to uplift this tectonic unit (MCT + HOTTER ROCKS). The design and the physical stance of the Himalayas is a nature’s masterpiece. As the Similarly, in another tectonic phase, a major two plates locked horn, the Eurasian plate fault branched out from the MHT emplac- slowly started to override Indian plate cut- ing meta-sediments (constitute of both met- ting across the stratigraphy of the latter. The amorphic and sedimentary rocks) on top of boundary (structure=fault) between the un- younger sedimentary rocks called the Main der-riding Indian plate and Eurasian plate Boundary Thrust (MBT). Like the MCT, at mid-crustal depth is called Main Hima- this structure also accommodates plate layan Thrust (MHT), which is the root thrust shortening (Indian plate subduction under faults (Figure 2). the Eurasian plate results in shortening of Indian plate) and has been uplifted since its On the surface, this structure is manifested formation. as three distinct thrust faults, which are all formed at different time period (Figure 2). The youngest and most active structure in At an infant stage, the collision and plate the Himalaya is the Main Frontal Thrust motion along MHT resulted in transport of (MFT). It is often the proxy (some sort of old and hot rocks (crystalline unit) from In- evidences) for collision boundaries between dian crust and deposited on top of the rel- the two plates. It is along this structure atively younger rocks. This stratigraphical where maximum shortening takes place. discontinuity is called the Main Central Gradually, like its antecedent faults (MCT Thrust (MCT). With the time, the continued and MBT), the MFT will also be uplifted sliding on the MCT had uplifted the older and another younger fault will splay out and hotter rocks, while slip on the MHT also from the root thrust (MHT).

Figure 2: Cross-section or block model showing the architecture of the Himalayas (Source: USGS).

GEOSCIENCES AND MINING JOURNAL | 5 Geological Setting of Bhutan – (MBT) at the top, represents ~ 2-5 km A Synopsis thick young Miocene-Pliocene (~23 - 2.6 Ma) sedimentary rocks like sandstones, The geology across the entire Himalaya is conglomerate, shale and siltstone that are quite homogenous, characterized by a deformed during the Himalayan formation formed (folded and thrusted) sediments that (Bhargava, 1995; Long et al., 2011a; Long were deposited on the northern part of In- et al., 2011c). dian plate and in the Tethys ocean and with emplacement of the older or higher grade These younger rocks are overlain by about metasedimentary rocks on top of the young- 17 km thick up to low-grade metamorphism, er rocks by thrust faults (MCT, MBT, MFT). relatively older Paleoproterozoic-Devonian (~2500 - 358.9 Ma) metasedimentary rocks Geologically, Bhutan Himalaya is divided of LHS comprising of dolomite, limestone, into four tectonostratigraphic zones bound- phyllite, quartzite, slate, schist, orthogneiss ed by major thrust faults (Long et al., 2011b) that are bounded by MBT at the base and (Figure 3). From south to north, these are: MCT at the top (Gansser, 1983; Long et Sub-Himalayan Zone, Lesser Himalayan al., 2011a; Tobgay, 2012; McQuarrie et al., Section (LHS), Greater Himalayan Section 2013). (GHS), and Tethyan Himalayan (TH) Zone. The GHS, above the MCT and below the The Sub-Himalayan Zone, bounded by South Tibetan Detachment fault (STD, MFT at the base and Main Boundary Thrust represents > 24 km thick older or similar

Figure 3: Simplified geological map of Bhutan [modified after Long et al. (2011c)] showing location major tectonic units and major thrust faults. From south to north (see also the legend), the major tectonic units are: Sub-Himalayan Zone, LHS, GHS, and TH Zone. KT-Kakhtang Thrust and STD-South Tibetan Detachment

6 | GEOSCIENCES AND MINING JOURNAL aged rocks to LH [Neoproterozoic-Ordovi- marble, phyllitic quartzite of Tethys ocean cian (~1000 - 443.8 Ma)] but higher-grade (Gansser, 1983; Long et al., 2011a). metasedimentary rocks like schist, gneiss, quartzite, marble with leucogranite intru- The Paro Formation interpreted as tectonic sives, which is further sub-divided into two window within GHS (Grujic et al., 2002; To- litho-structural units: Structurally-Higher bgay et al., 2010) comprises of young (~500 GHS and Structurally-Lower GHS (Grujic to 450 Ma) high-grade metasedimentary and et al., 2002; Long and McQuarrie, 2010). calcareous rocks such as quartzite, calc-sil- Structurally-Lower GHS, above MCT and icate rocks, marble, quartz-garnet-stauro- below Kakhtang Thrust (KT), represents lite-kyanite schist with subordinate felds- Neoproterozoic-Ordovician (~1000 - 443.8 pathic schist, deformed leucogranite and Ma) metasedimentary rocks that are in- granitic orthogneiss intrusive (Gansser, truded by small young leucogranite bodies 1983; Tobgay, 2012). (Gansser, 1983; Long et al., 2011a; Long et al., 2011c). Structurally-Higher GHS, above Mineral Deposits in the KT and below STD, comprises high-grade metasedimentary rocks of that are intrud- Himalayas ed by large young leucogranites (Gansser, 1983; Long et al., 2011a; Long et al., 2011b; It is important to understand that mineral Long et al., 2011c). deposits of economic significance do not occur randomly. They are indeed driven by The TH Zone, above STD and within GHS, plate tectonics and the general rule is that represents > 4 km thick relatively younger mineral systems associated with different Cambrian-Cretaceous (~541-66 Ma) fos- tectonic settings are different (Figure 4). sil-bearing sedimentary and low-grade met- For example, tin, tungsten, and molybde- amorphic rocks like limestone, sandstone, num are more favored in the metamorphic shale, marble, quartzite, slate, phyllite, terrain of continental arc where granite is fossiliferous limestone, diamictite, schist, emplaced; whereas chromium, zinc, copper and gold are typical of back arc tectonic setting (Figure 4).

Figure 4: Tectonic settings of the metal deposits (From Skinner and Porter, 1987). Note that there is not much of overlap in the mineral deposit types among the different tectonic settings.

GEOSCIENCES AND MINING JOURNAL | 7 Figure 5: Himalayan orogeny or architecture showing different ore mineralization potential (from A.K. Pachauri, 1992).

The mineral deposits associated with differ- Mineral Resources of Bhutan- ent tectonic architecture or units of Hima- an Overview layas are shown in Figure 5. In general, the Himalayas are not a host to significant me- Mineral resources are the national treasures tallic mineral deposits. This may relate to and its sustainable mining and development either its young age or significant erosional are critical to the growth and macroeconom- rate. As a young mountain of about 55 mil- ic stability of every nation. The Himalayas, lion years, there may not have been enough in general, is known for the huge reserve of time to develop magmatic-hydrothermal industrial minerals and construction stones, systems to result in metal mineralization in gravel and sand. Mineral resources in the the crust (Mitchell, 1983). The lack of any Bhutanese Himalaya include industrial min- exposed large orogenic gold deposits (gold erals like dolomite, limestone, quartzite, deposits related to mountain building pro- gypsum, talc, marble, graphite, ironstone cesses) aged younger than about 55 million or low-grade iron ore, calc-tufa, clay, fuel years shows that more than 55 million years mineral coal, slate and construction stones, are required to erode and expose the poten- gravels and sand, These mineral resourc- tial mineralized zones of mid-crust at the es form an important raw material for the surface (Goldfarb et al., 2001). Further, the domestic mineral-based industries that major portion of Himalayas are also covered produce calcium, carbide, cement, ferrosil- by GH rocks schist and gneiss. These high- icon, chicken feeds, Plaster of Paris (PoP) grade metamorphic rocks of about 1800 and wall putty or white cement, and impor- about 1800 - 600 million years indicate tant input for the construction industries. removal of core orogenic gold mineralized Dolomite, gypsum, marble, coal, talc and zones by erosion. These rocks would have construction stones and gravel are also ex- been underlying the most potential orogen- ported to the neighbouring countries India, ic gold-vein formation within most orogens Bangladesh and Nepal for various industrial (Goldfarb et al., 2001). uses and infrastructural development. construction stones and gravel are also exported

8 | GEOSCIENCES AND MINING JOURNAL to the neighbouring countries India, Bang- the growth of the tourism sector and rise in ladesh and Nepal for various industrial uses global demand, quite abundant fine miner- and infrastructural development. als or semi-gem-quality crystals like ber- yl, garnet, quartz, calcite, tourmaline, and The occurrence of high-valued metallic decorative stones has economic potential. mineral deposits such as copper, tungsten, The summary of metallic and non- metallic lead, zinc, and Rare Earth Elements are also mineral resources of Bhutan are provided in known in Bhutan (Bhargava, 1995). With Table 1 and 2.

Table 1: Summary of metallic mineral resource of Bhutan. Note that only significant ones are provided here.

Table 2: Summary of non-metallic mineral resource of Bhutan. Note that only significant ones are provided here.

GEOSCIENCES AND MINING JOURNAL | 9 References cian Lesser, Greater, and Tethyan Himalayan strata of Bhutan. Gondwana Research, 23, Bhargava, O. (1995). The Bhutan Himalaya, A 1491-1510. Geological Account: Geological Survey of Mukherjee, S., Mukherjee, B. K. and Thiede, India. R. C. (2013). Geosciences of the Himala- Department of Geosciences, University of Ar- ya-Karakoram-Tibet orogen. International izona. Ore minerals and the Himalayan Journal of Earth Sciences, 102, 1757-1758. Orogeny. Retrieved from http://www.geo. Norbu, P. (1997). Mineral Resources of the arizona.edu/geo5xx/geo527/Himalayas/ores. Kingdom of Bhutan. Vol I, Metallic Deposits htm. and Occurrences. In: Department of Geolo- Gansser, A. (1983).Geology of the Himalayas. gy & Mines, Thimphu. Birkhaüser Verlag. Tobgay, T., Long, S., Mcquarrie, N., Ducea, M. Goldfarb, R.J., Groves, D.I. and Gardoll, S. and Gehrels, G. (2010). Using isotopic and (2001). Orogenic gold and geologic time: a chronologic data to fingerprint strata: Chal- global synthesis. Ore Geology Reviews, vol. lenges and benefits of variable sources to 18, no. 1-2, pp. 1-75 tectonic interpretations, the Paro Formation, Grujic, D., Hollister, L. S. and Parrish, R. R. Bhutan Himalaya. Tectonics, 29. (2002). Himalayan metamorphic sequence Tobgay, T. (2012). Tectonics, structure, and met- as an orogenic channel: insight from Bhu- amorphic evolution of the Himalayan fold- tan. Earth and Planetary Science Letters, thrust belt, western Bhutan. Doctor of Phi- 198, 177-191. losophy Dissertation, Princeton University. Hodges, K. V. (2000). Tectonics of the Himala- The University of Western Australia. (2015). ya and southern Tibet from two perspectives. Advanced Ore Deposits Lectures and Re- Geological Society of America Bulletin, 112, sources. Perth: The University of Western 324-350. Australia. Long, S. and Mcquarrie, N. (2010). Placing limits on channel flow: Insights from the Bhutan Himalaya. Earth and Planetary Science Let- ters, 290, 375-390. Long, S., Mcquarrie, N., Tobgay, T. and Grujic, D. (2011b). Geometry and crustal shortening of the Himalayan fold-thrust belt, eastern and central Bhutan. Geological Society of America Bulletin, B30203.1. Long, S., Mcquarrie, N., Tobgay, T., Grujic, D. and Hollister, L. (2011c). Geologic map of Bhutan. Journal of Maps, 7, 184-192. Long, S., Mcquarrie, N., Tobgay, T., Rose, C., Gehrels, G. and Grujic, D. (2011a). Tec- tonostratigraphy of the Lesser Himalaya of Bhutan: Implications for the along-strike stratigraphic continuity of the northern In- dian margin. Geological Society of America Bulletin, 123, 1406-1426. Mcquarrie, N., Long, S., Tobgay, T., Nesbit, J., Gehrels, G. and Ducea, M. (2013). Docu- menting basin scale, geometry and prove- nance through detrital geochemical data: Lessons from the Neoproterozoic to Ordovi-

10 | GEOSCIENCES AND MINING JOURNAL MINERAL EXPLORATION FOR MINING DEVELOPMENT Tashi Tenzin1

Mineral Exploration for Mining tion of potential resource targets using remote sensing and airbone geophysics (e.g. Development aeromagnetics, satellite data analysis), geochemical mapping, and field survey. Mineral exploration is a geological study Prospecting and exploration: to locate of a mineral deposits to determine charac- and identify the potential deposit, evaluate teristics of mineral deposit (size, shape and or model mode of occurrences such the size, extent) and prove the reserve (quantity) and shape and extent and prove the reserve and grade (quality). The result of exploration grade of the deposit. is critical for mining development and investment such as mine design and planning, preparation of environmental management Geological Mapping and plan, quality control and production plan- Mineral Exploration in Bhutan ning, and slope stability mitigation measures. The geological mapping in Bhutan commenced as early as mid-nineteenth century The minerals mined are processed in the (cf. Gansser, 1983). However, the system- industry for various applications (e.g. phar- atic mapping on country scale and mineral maceuticals, electronics, airplanes and cars, prospecting and exploration started only telecommunications and IT, cement and after 1960s by Geological Survey of India metals, fertilizers, jewelry etc.). With the in- (GSI) and Augusto Gansser, a professor crease in global population, the demand for from Switzerland. The results from their these resources will increase. However, it works include publication of books on geol- is becoming more difficult for geologists to ogy of Bhutan and geological map of Bhu- discover new mineral resource targets with tan on 1:500000 scale (e.g. Gansser, 1983; depletion of the known deposits and geolog- Bhargava, 1995). The mining and mineral ical complexity. This requires a systematic based industries in Bhutan started following scientific approach that will form a basis for the mineral exploration of GSI (e.g. cement, mining development, which are as follows; ferro-silicon, calcium carbide, Plaster of Paris). The subsequent geological map of Regional geological survey: involves sys- Bhutan on 1:500000 scale include the publi- tematic mapping of geology and mineral cation by Long et al. (2011). resources including identification and loca-

1 Tashi Tenzin, Executive Geologist, Department of Geology and Mines, Thimphu, Bhutan. Master of Geoscience, The University of Western Australia. Email: [email protected]

GEOSCIENCES AND MINING JOURNAL | 11 Table 1: Major exploration works of DGM in recent field seasons Exploration Activity Location Exploration Stage Status Reassessment of gypsum Khothagpa, Pemagatshel Dzongkhag Detailed Completed (auctioned mine) Geological study of Coal deposit Southeast belt of Bhutan Prospecting Completed (auctioned mine) Reassessment of dolomite Chuniakhola, Phuntshopelri Geog, Detailed Ongoing deposit (auctioned mine) Samtse Dzongkhag Marble mapping Between Kariphu and Shaba under Regional scale Completed Thimphu and Paro Dzongkhag mapping Exploration of cement grade Edi-Bagala, Gongdue Geog, Mongar Detailed mapping and Ongoing limestone Dzongkhag drilled

Exploration of dolomite deposit Suktikhola western block, Phuntshopelri Detailed Mapping Completed Geog, Samtse Dzongkhag Exploration of ferro-silicon Shingkhar Lauri, Samdrupjongkhar Regional scale Completed grade quartzite Dzongkhag mapping

The systematic geological mapping on Recent Mineral Exploration th 1:50000 scale by DGM started only from 9 Initiatives of DGM Five Year Plan. Till date, about 40 percent of the country is mapped. The mineral explor- DGM in recent years has initiated mineral atory works were continued by DGM and resources mapping and exploration of min- ensured continuous supply of raw material erals such as limestone, marble, gypsum, to the mineral based industries and construc- dolomite and coal, which are important for tion sector. The current information on geol- planning and decision-making of mining in- ogy, geotectonics, and mineral resources of vestment, trade and industry development. Bhutan, mainly generated through conven- The exploratory works also include the ar- tional field-based mapping, is very limited eas which were not previously explored. and mapping is seriously constrained by difficult terrain, soil and vegetation cover. The The major exploration initiatives of DGM true potential of mineral resources including in recent field seasons are provided in Ta- subsoil potential is yet to be known. Thus, ble The results from the recent mapping and a systematic regional geological survey exploration of marble, limestone, dolomite, in 1:50000 scale to build comprehensive quartzite and gypsum show great potential knowledge base on geology, geotectonics, for mining. mineral resources, and geological hazards using modern mapping methods (remote In 12th Five Year Plan, DGM intends to de- sensing, airborne geophysics) in conjunc- velop a Geological Survey Strategic Plan tion with field mapping, geochemistry, and with support from Japan International Coop- geochronology to promote exploration, eration Agency (JICA). This strategic plan mining, trade and investment is required. is expected to provide roadmap to build a systematic and comprehensive geology and mineral resources knowledgebase of Bhu- tan to attract investment in exploration and mining, and promote trade and industry in

12 | GEOSCIENCES AND MINING JOURNAL Figure 1: The author at marble mapping Figure 2: Diamond drilling works at Edi for fieldwork in Khariphu, Thimphu Dzongkhag exploration of cement-grade limestone during during field season 2016-17. field season 2017-18. the long run. While the development of the strategic plan is initiated, DGM will contin- ue to prospect and explore more minerals in the country through geological mapping and mineral exploration for mining and national development of Bhutan.

References:

Bhargava, O. (1995). The Bhutan Himala- ya, A Geological Account: Geological Survey of India. Gansser, A. (1983).Geology of the Himala- Figure 3: RTK GPS survey for a geological yas. Birkhaüser Verlag. reassessment of Chuniakhola dolomite deposit Long, S., McQuarrie, N., Tobgay, T., Grujic, in the current field season 2018-19. D., & Hollister, L. (2011). Geologic map of Bhutan. Journal of Maps, 7(1), 184- 192.

Figure 4: total station (right) survey for a geological reassessment of Chuniakhola dolomite deposit in the current field season 2018-19.

GEOSCIENCES AND MINING JOURNAL | 13 LANDSLIDE HAZARD IN BHUTAN Ugyen Namdol1 and Tashi Tenzin2

Figure 1: Top - Jumja landslides along one of the main highways in Bhutan (Photo: Norwe- gian Geological Institute). Bottom – highway landslide blockage clearing (Photo: Kuenselon- line).

Landslides are one of the most common For example, roads, which is a lifeline of geological hazards in Bhutan. It poses great economy, is cut off for days and weeks by threats to the lives of Bhutanese people and landslides and the government spends huge its economy (Kuenza et al., 2004). clearing and repairing budget (Figure 1).

1 Ugyen Namdol, Geologist, Department of Geology and Mines, Thimphu, Bhutan. BSc. Geology, Osmania Universi- ty, India. Email:[email protected] 2 Tashi Tenzin, Executive Geologist, Department of Geology and Mines, Thimphu, Bhutan. Master of Geoscience, The University of Western Australia. Email: [email protected]

14 | GEOSCIENCES AND MINING JOURNAL The landslide at the right abutment of PHPA-I hydropower dam site is one of the main reasons for significant delay and huge cost escalation of the project. The risk from landslide is likely to increase with increase in land-use development.

What is a landslide?

Landslide is a downward movement of soil, rock, or debris (soil and rock) in varying volume and velocity (depending on the local geological and slope conditions) under the influence of gravity. Landslide is broad- ly classified as slide, fall, flow, topple, and spread based on the type of movement and material, and velocity (Figure 2).

Other forms of landslide include avalanche, creep or a complex type. While most forms of landslides that move rapidly are detect- able, some form like creep that move at a very slow pace (e.g. few centimeters per year) go undetected for many years. How- ever, such type of landslide can potentially be catastrophic. It is very important to look out for surface indications, which may in- Figure 2: Classification of different types of clude cracks on the land, bent trees, tilted landslide. (From pronkplanets.wordpress.com) fences and electric poles, bulging, overturn- ing and cracking of walls, hummocky terrain, cracks on the floors and walls of houses and sunken roads (Figure 3).

Causes of Landslides

So long as the resisting forces, mainly defined by the shear strength (cohesion and internal friction) of the earth materials (soil and rock) on the slopes, is equal to or greater than the driving forces, the mass will be in equilibrium and therefore, the slope will remain stable. The driving forces are mainly Figure 3: Surface indication of creep type of defined by shear stress developed along the landslide (Photo: Wyoming State Geological potential failure surface or increase in the Survey).

GEOSCIENCES AND MINING JOURNAL | 15 weight or decrease of shear strength of the tions further accelerates the slope failures. soil and rock due to factors such as water Mega earthquakes (which our country is (precipitation, surface run-off, sub-surface vulnerable to) can be one of the major trig- saturation, toe cutting and erosion); seismic gering factors. The landslide hazards are not activity; human activities (modification of a matter of concern if it does not interfere slope geometry, improper drainage, removal with the human and its properties. However, of vegetations, addition of weight on slopes such hazards become risks when it interacts by constructions, etc.). It is therefore, criti- with human and its properties. cal for humans to make effort not to imbal- ance the forces and consider the capacity of What can be done to Prevent or the ground through proper site suitability studies before a civil engineering construc- Treat the Landslides? tion is undertaken. Landslide is a natural geomorphological The main factors responsible for landslides process and the hazard is inevitable. The in Bhutan are weak geology, precipitation greater challenge to scientific community (rainfall, snow) and slope inclination or ge- today lies in proper understanding of its ometry. Human activities such as cut and fill characteristics and accurate failure time pre- for roads, settlements, removal of vegeta- diction because of geological and climatic

Figure 4: Slope stabilization measures (Photo: http://www.sinaiconstruction.net).

16 | GEOSCIENCES AND MINING JOURNAL uncertainties. However, landslide can be The role of DGM in landslide recognized, and the following three solutions can help to prevent or reduce risks as- studies sociated with landslide hazards: DGM has the mandate to study landslide • Land-use planning based on geoscientif- hazards to reduce risks associated with it. ic knowledge to keep human activities Currently, the landslide study includes haz- far from landslide hazardous areas and ard and risk assessment on both regional introduce proper land use practices. For (e.g. Figure 5) and local scales along high- example, landslide susceptibility or haz- ways, site suitability for human settlements ard map and inventory map can be useful and construction of infrastructures, monu- in this aspect. ments, etc. • Slope stabilization treatments – may include retaining walls, drainage, bioen- The regional scale study identifies critical gineering, slope modification (terracing areas, which requires further detailed stud- and benching), installation of wire mesh, ies. At local scale, detailed assessment is micropile walls, sheet piling, anchoring, carried out that includes classification of the shotcreting, rock bolting, soil nailing, landslide and its characteristics, causative geotextiles, etc. (Figure 4). factors, estimation of degree of hazard and • Monitoring – using both contact and re- risks, and recommendation of treatment and mote monitoring instruments. Contact monitoring measures. monitoring may include instruments such as extensometer, inclinometer, pie- zometer, tiltmeter, etc. Remote monitoring may include use of satellite data, Li- DAR, drone, total station, GNSS, etc.

The consequences of non-timely implementation of treatment and monitoring can be catastrophic and therefore, it is important to properly recognize the landslide and understand its characteristics including its stage of failure (early to total) through systematic and detailed geological investigation in order to select the right treatment and monitoring techniques at right time. This will not only prevent or reduce adverse impact of landslides, but also ensure sustainable treatment and monitoring techniques, and save cost. Treatment of landslide is a dynamic process where monitoring plays a significant role in better understanding its evolution and therefore, may require implementation of any additional treatment measures. Figure 5 : Landslide hazard map of Barsa watershed (NAPA II project).

GEOSCIENCES AND MINING JOURNAL | 17 References:

Hunt, R. E. (2007). Geologic hazards: a field guide for geotechnical engineers. CRC Press. Kuenza, K., Dorji, Y. and Wangda, D. (2004). Landslides in Bhutan. Natural Hazards Control and Assessments (NHAZCA srl). (2017). Lecture notes on Landslide monitoring and design of landslide monitoring programs in Bhutan.

18 | GEOSCIENCES AND MINING JOURNAL National Earthquake Monitoring Network Phuntsho Pelgay1, Dowchu Drukpa2 and Nityam Nepal3 These issues are addressed through collaborations with local and international insti- Abstract tutions.

Earthquakes in the Himalaya pose great National Earthquake threat to human lives and socio-economic Monitoring Network (NEMN) settings of the region due to high population density and poor economic conditions. Geological processes that trigger earth- In Bhutan, the only mega earthquake (Mw quakes cannot be ascertained. While it is 8+) that ruptured frontal thrust over the last important to understand the seismic haz- three centuries was in 1714 A.D - which, ards, its equally important to care and pre- according to historical account, devastat- pare for earthquake disaster. Accordingly, to ed entire Bhutan. In recent years, Mw 6.1 prepare for disaster or to mitigate the risk, earthquake in eastern Bhutan instigated the causative phenomena for hazard should multi-million dollar loss and claimed few be well monitored and understood both in lives as well. Although, earthquake cannot local and regional scale for long period be prevented, its associated risk can be mit- (Bormann, 2009). Thus, to precisely quan- igated through strategic preparedness plan- tify the geological mechanisms leading to ning. To gear towards developing seismic earthquakes and associated hazards and to resilience in the country, first ever National provide accurate earthquake information for Earthquake Monitoring Network (NEMN) disaster response management, there is no was established in 2015. Currently, there surrogate to having establishment of earth- are 14 permanent source monitoring sta- quake monitoring network. tions and 20 earthquake intensity meters under NEMN. Although, providing near National Earthquake Monitoring Network real time earthquake source and intensity (NEMN) in Bhutan was founded in 2015 information to the government and public with six sets of seismic instruments to re- at large remain the primary objectives of cord earthquake events. With the financial NEMN, in the long run, data will be useful assistance from Japan Policy for Human in seismic hazard assessment among many Resource Development (PHRD) fund and other scientific applications. Operation of NEMN in-kind donations and technical assistance from Kyoto University and National Re- demands sound financial and human research Institute for Earth Sciences and Dis- sources which are our current challenges. aster Resilience in Japan established small 1 Phuntsho Pelgay, Executive Geologist, Department of Geology and Mines, Thimphu, Bhutan. Master of Earth Scienc- es, The University of Melbourne, Australia. Email:[email protected] 2 Dowchu Drukpa (PhD), Chief Seismologist, Department of Geology & Mines, Thimphu, Bhutan. Doctor of Philoso- phy, University of Montpellier, France. Email:[email protected] 3 Nityam Nepal, Geologist, Department of Geology & Mines, Thimphu, Bhutan. BSc. Geology, Osmania University, India. Email:[email protected]

GEOSCIENCES AND MINING JOURNAL | 19 Figure 1: Map showing the location of permanent & temporary Earthquake monitoring stations and Intensity Meter aperture seismic network consisting of six toring Network. permanent source monitoring stations and twenty intensity monitoring stations. Re- Source Monitoring Network gional Integrated Multi-Hazard Early Warn- ing System (RIMES), a regional body which Earthquake source monitoring constitutes monitors earthquake, tsunamis and extreme network of seismographs which are chan- weathers in Asia-Pacific, has expanded our nelled through real time telemetry system seismic network to include eight more per- to the central observatory server where data manent seismic vault stations. Currently, processing is done. Since, it is a precision NEMN consists of 14 permanent seismic technology, its robustness depends on fac- vault stations and 20 intensity stations in- tors such as site selection, sensor sensitivity, stalled throughout the country (Figure 1). assumed velocity models for wave travel Outside NEMN, there are three offline sta- times, quality of telemetry system, data log- tions installed in the remote northern lati- gers and overall design of the network (Ki- tude of the country under the ongoing proj- jko, 1977)some generalization of D-plan- ect framework of Science and Technology ning (minimization of the ellipsoid volume Research Partnership for Sustainable Devel- of earthquake location errors. opment (SATREP) funded by Japan Science and Technology Agency (JST). Seismometers The primary sensors in our network are For the purpose of segregating two dis- Short Period (SP) PK110, VBB Gurlap tinct objectives and functional services of CMG 3T and BB Nanometrics Trillium NEMN, we deconstruct and present NEMN 120. In six stations, namely, Thimphu, into two constituent components 1) Source Bumthang, Trashigang, Samdrup Jongkhar, Monitoring Network and 2) Intensity Moni- Gelephu and Samtse SP PK and Broad Band

20 | GEOSCIENCES AND MINING JOURNAL (BB) CMG 3T are collocated. In three oth- munication channel is fibre optic with last er stations, namely, Wangdue, Mongar and mile as radio link. The advantage of using Trongsa, BB Trilium 120 and SM Titan are duplex communication system is its abili- collocated. ty to access remotely that in turn, enables to retrieve missing data package and do Data transmission protocol maintenance. RIMES stations use cellular network as main communication protocol Due to differences in the nature of funding and data transmission in UDP package. It is and equipment system, the communication standard communication where the remote protocol for PHRD-NIED-Kyoto stations station pushes the data to central server and RIMES stations are different. The for- without backward communication. The data mer, which consists of six stations with six from both the systems are integrated into an SP and VBB sensors use Transmission Con- archiving and processing software called trol Protocol (TCP)/ Internet Protocol (IP) SeisComP which is housed in Department for data transmission and it is duplex com- of Geology and Mines office, Thimphu munication system. The main trunk com- (Figure 2).

Figure 2: Top: Simplified picturesque diagram showing all types of instruments in our network and data acquisition systems used. Abbreviations are described in text. Orange and red dash lines indicate systems yet to integrate into central processing system, i.e SeisComP. The light pink bar divides RIMES network to right and other to left. Below: Sketch showing two different communication protocols used by two networks. DM24 and GPS loggers are currently not in use. There are currently three GNSS (continuous GPS) installed under RIMES.

GEOSCIENCES AND MINING JOURNAL | 21 Information dissemination and Early Warning Systems (EWS)

One of the important objectives of real-time seismic monitoring network is dissemination of earthquake event to the disaster management authorities and public - either as early warning or post-earthquake information. Earthquake EWS is still a new concept. Any settlement located far away from epicentre and has well drilled people, EWS can be very effective in alerting people, auto shutting down certain important systems and rapid post disaster response (Allen, 2015). EWS is based on a concept of lead time between P-Waves and destructive, and Surface Waves, which ranges from few seconds to tens of seconds – depending on the epicentral distance (Allen, 2015). However, for EWS to be very effective, seismic monitoring network should have state-of-the-art communication and processing systems. Currently, our network has latency of 5 seconds and SeisComP has another 10-20 seconds to detect the event. Given such latency, providing real time early warning is a lim- itation. Although, EWS is a work in prog- ress, providing post-earthquake information immediately can also reduce the magnitude Figure 3: Schematic flow of SeisComP auto of the disaster. This first-hand information working architecture. Same coloured boxes refer Actions with their corresponding module(s) on earthquake event is significant for the and program used to generate output. For decision-makers for planning immediate more read refer https://www.gempa.de/prod- relief responses. However, information dis- ucts/seiscomp3/ semination should be done with established Standard Operating Procedure (SOP) to becomes fully operational, SOP will be in avoid alerting public unnecessarily. For in- place. stance, sending earthquake information for every small magnitude may create unwar- Earthquake Intensity Meter ranted havoc or nuisance to the public. Network

Currently, the network is not monitored Earthquake parameters such as magnitude, 24x7, so dissemination of information hap- depth and location, derived from earthquake pens only on ad-hoc basis. Once network source monitoring network, can only give

22 | GEOSCIENCES AND MINING JOURNAL Figure 4: Near Real-time intensity data displayed on the map. The decimal point rounds off to next higher MMI scale for interpretation rough estimation on the damage impact. assistance from PHRD grant and technical The damage impact due to an earthquake assistance from NIED, Japan and Philippine has direct correlation to Peak Ground Ac- Institute of Volcanology and Seismology celeration (PGA) (Inoue et al., 2015; Lasala (PHIVOLCS), Philippine. et al., 2015)peak ground acceleration and peak ground velocity. The intensity meters Design evaluate earthquake effects using the Phil- ippine earthquake intensity scale – PHI- We designed a seismic intensity meter with VOLCS Earthquake Intensity Scale (PEIS. an inexpensive but accurate intensity but By measuring PGA, seismic intensity can accurate acceleration sensor connected to be calculated and extent of damage can be, a Raspberry PI operating system that cal- thus, precisely assessed. Under NEMN, culates seismic intensity from acceleration around 20 accelerometers have been in- waveform data, displays intensity values stalled throughout the country (see Fig. 4) on a screen, stores waveforms and intensi- to record seismic intensity with financial ty data locally and sends out intensity data

GEOSCIENCES AND MINING JOURNAL | 23 every few seconds over the Internet (Figure information are used in spatial interpolation, 5). The earthquake information is sent every rapid damage assessment and prediction of 10 seconds in text format via internet to the damage scenarios. central server. The information is also displayed in remote monitor. Future scope and conclusion

Uses of earthquake intensity information A key to successful monitoring of earthquakes which has long term benefit of gen- Earthquake instrumental intensity informa- erating scientific data for hazard mitigation tion is extensively used both for post-disas- is stable financing. In the past two decades ter relief responses as well as for prepared- about half a million of human lives have ness for disaster. Currently, we are using been lost due to earthquakes, and economic it as information source for site-specific losses of about $200 billion (Wu & William, response for a given earthquake – meaning 2010). Future losses will be even greater as when an earthquake is triggered only MMI rapid urbanization is taking place world- values are shown as discrete values on the wide. For example, the recent Japanese Fun- map (Figure 5). damental Seismic Survey and Observation Plan (costing several hundred million US While this is also useful in information dis- dollars) is a direct response to the economic semination - as sensors are installed in dis- losses of about $100 billion due to the 1995 tricts where relative population density is Kobe earthquake (Wu & William, 2010). In higher than rural areas – having continuous addition to scientific and technological chal- intensity distribution map would be much lenges in monitoring earthquakes, seismol- more effective in disaster response and pre- ogists must pay attention to achieve stable paredness management. long-term funding, effective management and execution, and delivery of useful prod- The USGS models like Shakemap and ucts to the users. ShakeCast are examples of how intensity

Figure 5: Real-time data transmission protocol of intensity network. GWAN stands for Govern- ment Wide Area Network. The text format in the bottom figure is used for both transferring and storing data.

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GEOSCIENCES AND MINING JOURNAL | 27 INTEGRATED GEOPHYSICAL IMAGING TECHNIQUES FOR SLOPE STABILITY STUDY AT CHAPCHA Dowchu Drukpa1, Phuntsho Pelgay2, Nityam Nepal3 , Karma Namgay4 and Lungten Chedup5

Abstract Introduction

Integrated geophysical techniques involv- The geologically fragile and steeply slop- ing electrical resistivity tomography (ERT) ing mountainous terrain of the study area in and seismic refraction tomography (SRT) particular, and the Bhutan Himalayas by and combined with borehole information proved large, poses mounting challenge for sustain- to be useful in studying complex landslide able socio-economic development in the bodies. At Site 1, our geophysical results country. Slope instability problem is further show predominant colluvium materials and exacerbated due to variation in the intensity gravel/pebbles with varying degree of sat- of precipitation rates—an increasingly er- uration level. The overburden thickness in ratic and extreme weather pattern attribut- the middle section of the exceeds 50m Site 1 able to climate change (Resenzweig et al., and seem to thin out towards the upper and 2001; Bo et al., 2008; Alvioli et al., 2018). lower part of the slope indicating a circular The study area is located about 1 hour drive slip motion of the landslide. At Site 2, the overburden colluvium materials is interpret- south of Thimphu, along the erstwhile ed to be relatively thin compared to Site 1. Thimphu-Phuentsholing highway—now The relatively lower than normal resistivity diverted along the Damchu-Chukha bypass distribution and P-wave velocity interpreted road (Figure 1). to be associated to the bedrock at Site 2 correlates well with the borehole (BH-2) data that show highly weathered and fractured bedrock even at deeper depths of 40m.

1 Dowchu Drukpa (PhD), Chief Seismologist, Department of Geology & Mines, Thimphu, Bhutan. Doctor of Philosophy, University of Montpellier, France. Email:[email protected] 2 Phuntsho Pelgay, Executive Geologist, Department of Geology and Mines, Thimphu, Bhutan. Master of Earth Sciences, The University of Melbourne, Australia. Email:[email protected] 3 Nityam Nepal, Geologist, Department of Geology & Mines, Thimphu, Bhutan. BSc. Geology, Osmania University, India. Email:[email protected] 4 Karma Namgay, Geologist, Department of Geology and Mines, Thimphu, Bhutan. BSc. Geology, Osmania University, India. Email:[email protected] 5 Lungten Chedup, Lab Technician, Department of Geology and Mines, Thimphu, Bhutan. [email protected]

28 | GEOSCIENCES AND MINING JOURNAL Figure 1: Location map of the study area at Chapcha, Chukha Dzongkhag. Objective

The primary objective of the study is to de- lineate the complex subsurface landslide material types and hydrological conditions and possibly image the slip surface of the landslide body based on analysis of electrical resistivity distribution and travel-time characteristics of P-wave.

Employing non-invasive geophysical methods, that can cover large areas incurring less time and cost, core-drilling techniques were performed at two locations to correlate the lithological-strata interpreted from the geophysical methods. Through this approaches we aim to better constrain the subsurface material types and hydrological conditions so that appropriate remedial measures can be advised to mitigate slope instability problem in the area. Geology of the Study Area

As shown in Figure 2, geologically the Figure 2: Geological map of western Bhutan study area is part of the Paro Formation and the study area at Chapcha (After Tobgay consisting of high-grade meta-sedimentary et al., 2010)

GEOSCIENCES AND MINING JOURNAL | 29 and calcareous rocks including calc-silicate Methodology rocks, marble, quartzite and quartz-garnet- mica-schist (Tobgay et al., 2010). Sever- We adopted electrical resistivity tomogra- al tell-tale signs of instability such as land phy (ERT) and seismic refraction tomog- subsidence, tilted trees, hummocky terrain, raphy (SRT) methods to study the near-sur- cracks on the building, etc. were observed in face geological settings in the study area. the field (DGM field report, 2019). The area is characterized with thick colluvium depos- ERT principle its adorned with numerous spring water. ERT method involving 2D or 3D method, is the most preferred and widely used meth-

Figure 3: Principle of electrical resistivity and typical field set-up (top); schematic diagram de- picting commonly used geometric configuration (array type) for ERT data acquisition (bottom).

30 | GEOSCIENCES AND MINING JOURNAL od nowadays. This method is especially Resistivity is computed using the formula ρ relevant to study geological settings where = K × (V ÷ I), where K denotes geometric vertical and horizontal subsurface materi- configuration used in the resistivity data ac- al variations are, more often than not, the quisition (Figure 3). prevalent conditions in subsurface investi- gations. In ERT survey, tens to hundreds of SRT principle electrodes are connected to central automatic switching system that activates four elec- Seismic refraction is a commonly used geo- trodes at a time, thus significantly speeding physical technique to image the subsurface up data collection time in the field. Most by applying the physics of acoustic wave modern ERT equipment comes with option propagation through different materials in to select any or multiple array types that can the ground. The main physics that governs be used to compare the apparent resistivity the propagation of seismic waves in medi- results from each method. um with varying density is the Snell-Des- cartes’ law which can be expressed as: The fundamental principle of ERT is based on Ohm’s Law of electrical impedance (sin(i))/(sin(r))=V1/V2 where a known amount of current (I) is in- jected into the ground using the current elec- where V1 and V2 represents the velocity of trodes and the corresponding voltage (V) is layers 1 and 2, respectively; i represents the measured at the ground surface through the angle of incidence and r represents the an- potential electrodes (Figure 3). Using the gle of refraction. As shown in Figure 4, if measured voltage (V) and known amount V2 > V1, then as i increase r will increase of current (I), resistance (R) is calculated. and at a critical angle of incidence (ic), angle

Figure 4: Travel-time curves for direct and head waves from single refractor.

GEOSCIENCES AND MINING JOURNAL | 31 of refraction (r) becomes 90°. In seismic ometry and topography are required. In the refraction, only critically refracted and first shallow sub-surface, attenuation or absorp- arrival energy are considered, while other tion of seismic energy may limit utility of waveforms such as reflection, direct arriv- survey. Source and receiver coupling is crit- als, surface waves, etc. are ignored. ical, such that data quality is site-dependent.

The travel-times of refracted seismic waves Data acquisition and processing are interpreted in terms of subsurface seismic velocity distribution which can be used Electrical Resistivity to characterize subsurface materials (e.g. depth to bedrock interface). Turning-ray The ERT data were acquired at two main tomography uses refracted first arrivals Sites, Site 1 and Site 2, as shown in Figure to compute a near-surface earth model by 5. We used ZZ-FlashRes Universal 61 chan- minimizing the difference between calculat- nel resistivity equipment with 64 electrodes ed and observed travel times. The method (http://www.zzgeo.com/). Injection of cur- inherently assumes an increase in P-wave rent was done using 100AH battery. velocity with depth. Gradual increase in P-wave velocity causes P-waves to dive or RT data acquisition for all the profiles were turn. Low velocity zones may not be detect- done using Dipole-Dipole, Wenner and ed properly, and their presence may lead to Schlumberger geometric configuration. erroneous results. Prerequisites include that the surveyed area should be larger than the At Site 1 two profile lines, A-A’ aligned area of interest. Accurate surveying of ge- along the slope direction and BB’ perpendic-

Figure 5: Map showing geophysical profile lines at the study area in Chapcha.

32 | GEOSCIENCES AND MINING JOURNAL ular to profile A-A’, were performed main- obtained using Wenner and Schlumberger taining an electrode interval of 3m and 4m, arrays were saved as grid data and exported respectively. This translates to a total survey to golden surfer® software. spread length of 189m for line A-A’ and 252 for line B-B’. The borehole (BH-1) with Seismic Refraction maximum drilled depth of 51.5m is located approximately between 168-171m distance Using 24 channel DAQLink-3 equipment (i.e. in between electrode No. 7 & 8) in case from Seismic Source®, we performed three of profile A-A’ and approximately at 148m seismic refraction profile lines—2 lines at distance (electrode # 26) for profile B-B’. Site 1 and 1 line at Site 2 (Figure 5). Seis- To constrain the subsurface material along mic energy were generated by hammering the entire slope at Site 1, we performed a 10 kg hammer on the metal plate. The SRT separate ERT line instead of a roll-along profile X-X’ at Site 1 is aligned almost in survey which was not feasible due to mo- the North-South direction and coincident tor highway right at the end of profile A-A’. with resistivity line A-A’ towards the south- An electrode interval of 4m (spread length= ern end of the profile. We used 3.5m geo- 252m) were maintained for the profile C-C’ phone intervals corresponding to a survey and D-D’ to acquire ERT data along these spread length of 80.5m. Borehole, BH-1, is profiles as shown in Figure 5. located at geophone # 7(distance of 21 m). ERT profile line E-E’ at Site 2 runs almost Similar to resistivity profile A-A’ at Site 1, in the Northeast-Southwest direction with roll-along survey has not feasible due to site electrode spacing of 3m (spread length= condition and therefore a separate profile 189m). The center of the profile is coinci- line Y-Y’ was conducted as shown in Figure dent with BH-2 location. 5. Profile Y-Y’ is aligned in North-South direction with electrode spacing maintained at Quality control of data were taken care-off, 3m (spread length = 79). thanks to ZZ-resistivity equipment’s provision to monitor on screen signal-to-noise. At Site 2, we acquired refraction data along Overall the data quality, ‘Q-value’, as pre- profile Z-Z’ with total profile spread length scribed in the ZZ-resistivity manual were of 92m spaced at geophone interval of 4m. well below ‘20’. The acquired data from the Borehole, BH-2, is roughly located between field were imported to Res2dinv® software geophones 17 and 18 at an approximate dis- (Loke, 2002) and inversion of the data were tance of 66m; profile alignment is not ex- performed after incorporating topographic actly coincident with BH-2 but roughly 20m data collected using kinematic GPS. In most West of BH-2 due to site constraints. cases, the inversion converges at 3-5 iter- ations with good fit between the observed Inline shots were made in between every and calculated models evaluated by the two geophones and deported shots were per- root-mean-square (rms) error of <10% in formed at appropriate distances from either case of Wenner array and between 10-15% end of the profile until signals at the farthest for Schlumberger array. The Dipole-Dipole geophone becomes weak or site conditions resistivity model returned high rms error and was not feasible to make proper shots. The therefore discarded. The final ERT models details of shots along the profiles are shown

GEOSCIENCES AND MINING JOURNAL | 33 in Table 1. At least 3 shots were made at of 2 specific modules: PickWin for picking each shot points and stacked to improve sig- first-arrival and PlotRefa for refraction anal- nal-to-noise ratio. ysis. The specific steps of SRT data processing is shown in Figure 6. The SRT data acquired were processed using 2D Seisimager® software which consist

Table 1: Location of seismic sources (shots) for each refraction profile lines in the study area

Figure 6: Refraction data analysis flow using Seisimager® software modules

34 | GEOSCIENCES AND MINING JOURNAL Results and interpretation The 2D refraction seismic model is shown in Figure 8. The BH-1 along refraction profile The results of processed geophysical data is located at 21m distance. The model show (and wherever relevant correlated with P-wave velocity distribution in the range borehole information) are presented below of 300-1100 m/sec. The thin top layer rep- to constrain the near-surface geological resented by P-wave velocity of 300 m/sec conditions in the present study area. is interpreted as dry loose colluvium with cobbles/pebbles. This can also be correlated Site 1 with core log shown in Figure 7. The second layer has P-wave velocity of 700 m/sec with The 2D resistivity distribution along profile layer thickness varying from 5-20m and is A-A’ & B-B’ are shown in Figure 7. The interpreted as relatively consolidated collu- area, in general, is dBH-1 dominated by low vium soil with cobbles/ pebbles/gravels (see resistivity (10-500 ohm.m) even at deeper Figure 8). The bottom layer represented by depths of 40m, indicating presence of thick P-wave velocity of 1200 m/sec is interpret- colluvium deposits with maximum depth of ed to be more consolidated materials made 53m is located at 168-171m distance along of cobbles/pebbles/gravels of micaceous profile A-A’ and 96m along B-B’. The low quartzite. In general, as reduced from both resistivity values (< 100 ohm.m) represent drill hole and P-wave velocity distribution, saturated unconsolidated colluvium materi- the subsurface material in the area is made als and cobbles/ pebbles as correlated with of colluvium soil and varying proportion BH-1 core log shown in Figure 7. The high- of cobbles, pebbles and gravels; variations er resistivity (>2000 ohm.m) may be repre- in P-wave velocity is mostly related to in- sentative of large boulders prevalent in the crease in compaction of materials with study area or most likely bedrock. depth and this has correlation to the N-value determined from SPT (Standard Penetration

GEOSCIENCES AND MINING JOURNAL | 35 Test) studies (DGM field report, 2019; Bery & Said, 2012 & 2013).

Results from ERT profile line C-C’ and D-D’ and refraction line Y-Y’ are shown in Figure 9. The notable observation from this profile is occurrence of high resistivity (>2500 ohm.m) towards the southern part of the profile at a depth of approximately 10- 15m. Towards the west end of profile D-D’, in-situ calcareous quartzite were observed at a depth of 10m which is also depicted in the 2D ERT model at 15-20m. Relatively competent calcareous quartzite were also exposed right below the end of the profile C-C’ which allow us to conclude that high resistivity zones interpreted to be associated with competent bedrock occur at shallow depth towards the southern end of the slope. The refraction model show similar material distributions corresponding to the P-wave velocity. In general, slope is characterized with thick overburden in mid-slope area and thins out at the top as well as the bottom, possibly indicating a landslide with circular slip failure surface.

Figure 7: 2D ERT section along profile A-A’ (top) and across slope profile B-B’ (middle); lithological description of subsurface materials in BH-1 (bottom) at Site 1

36 | GEOSCIENCES AND MINING JOURNAL Figure 8: P-wave velocity distribution along refraction line X-X’.

GEOSCIENCES AND MINING JOURNAL | 37 Figure 9: 2D ERT section along profile C-C’ (top), D-D’ (middle) and SRT section along seismic profile Y-Y’ (bottom).

38 | GEOSCIENCES AND MINING JOURNAL Site 2 sected at approximately 18-20m as shown in Figure 10. However, it should be noted The ERT at Site 2 profile E-E’ is shown in that the lower resistivity distribution inter- Figure 10. The drill hole, BH-2, is located preted to be associated to these metasedi- between 93-96m distance. From the 2D mentary bedrock highly jointed and high resistivity model it can be deduced that, in porosity of these rocks as observed in the contrary to ERT along profile A-A’, espe- core log. could be due to intensely frac- cially towards right half of the 2D model tured, The left half of the 2D ERT section and starting at BH-2 location, the resistivity show low resistivity (10-100 ohm.m), even distribution generally show higher resistiv- at deeper depths of 30 m, indicating thick ity of > 700 ohm.m at a depth of approxi- deposit of colluvium materials along with mately 20m. This correlates well with BH-2 cobble/gravel materials with high degree of core log that shows bedrock having inter- saturation.

GEOSCIENCES AND MINING JOURNAL | 39 Figure 10: 2D ERT section along profile E-E’ (top), 2D SRT model for seismic line Z-Z’ (middle); litho-log description for BH-2 (bottom) at Site 2.

The refraction seismic profile Z-Z’ near located at lower elevation and ca. 20m to the borehole, BH-2, is shown in Figure 10. west of BH-2. This could be the reason why BH-2 is located ca. 20 m to the west of pro- bedrock appears at shallower depth along file Z-Z’ at about 25-27m distance along the this profile compared to BH-2. The - over profile. The seismic line intersects the ERT lying layers are similar to what is observed profile E-E’ (that runs almost perpendicular in SRT profile X-X’ and is interpreted to to the seismic line) at approximately 75 m be mostly colluvium materials with mix of distance. The seismic tomography mod- saturated gravel, cobble and pebble mate- el show 4 different layers with ncreasing rials with increasing compaction at deeper P-wave velocity at depth. The deepest lay- depths. As observed in the ERT model, the er with P-wave velocity of 2200 m/sec at SRT model at BH-2 also show relatively low the BH-2 location appears around 10-12m P-wave velocity interpreted to be associated which is interpreted as the interface be- with highly fractured, weathered and joint- tween bedrock and overburden. However, it ed nature of the rocks in the subsurface as should be emphasized that the seismic line observed in the core log and field outcrop. is not coincident with the BH-2 location but

40 | GEOSCIENCES AND MINING JOURNAL Conclusions References

The integrated geophysical and borehole Alvioli, M., Melillo, M., Guzzetti, F., Rossi, data proved to be useful to study complex M., Palazzi, E., von Hardenberg, J., ... & Peruccacci, S. (2018). Implications of cli- near-surface landslide compositions in the mate change on landslide hazard in Central study area despite inherent limitations of Italy. Science of the total environment, 630, geophysical techniques such as signal to 1528-1543. noise and depth to resolution tradeoffs. Bo, M. W., Fabius, M., & Fabius, K. (2008, May). Impact of global warming on stability At Site 1 based on ERT, SRT and BH-1 core- of natural slopes. In Proceedings of the 4 th log, we conclude that near-surface landslide Canadian Conference on Geohazards: From material consist of colluvium and saturat- Causes to Management, Presse de Univ. La- ed zones of gravel/cobbles/pebbles with val, Quebec. thickness ranging over 50m at the BH-1 to Bery, A. A., & Saad, R. (2013). Seismic refraction velocities and engineering parameters sporadic appearance of bedrock at shallow analysis for environmental study. Electronic depths of 10-15m. The ERT profiles C-C’ Journal of Geotechnical Engineering, 18, and D-D’ at Site 1 clearly indicate thinning 3719-3730. of overburden towards the base of the slope Bery, A. A., & Saad, R. (2012). Correlation of and appearance of relatively competent bed- seismic P-wave velocities with engineering rock at shallow depths of 10-15m; outcrops parameters (N value and rock quality) for were also exposed at the top of the slope tropical environmental study. International suggesting a possible circular slip motion of Journal of Geosciences, 3(04), 749. the slide in the area. DGM final report on “Geo technical investigation of the identified slope instability at Chapcha, 2019. At Site 2 the BH-2 and geophysical results Loke, M. H. (2002). RES2DINV ver. 3.50. Rap- show a relatively thinner overburden with id 2-D resistivity and IP inversion using the the depth to the bedrock constrained around least square method. 20m. The highly weathered/fractured and Tobgay, T., Long, S., McQuarrie, N., Ducea, M. jointed bedrock encountered in BH-2 cor- N., & Gehrels, G. (2010). Using isotopic and relates well with the relatively lower than chronologic data to fingerprint strata: Chal- normal resistivity and P-wave velocity usu- lenges and benefits of variable sources to ally associated with competent calc-silicate tectonic interpretations, the Paro Formation, rocks prevalent in the study area. Bhutan Himalaya. Tectonics, 29(6).

GEOSCIENCES AND MINING JOURNAL | 41 REFORMS IN THE MINING SECTOR Pema Tshering 1

The Department of Geology and Mines could be part of the reasons for ineffective (DGM) is responsible for the administra- compliance monitoring of mines and related tion and management of mineral resources activities. and mining activities in the country. The Mines and Minerals Management Act of Under the existing Act and the Regulations, 1995 (hereafter referred as Act) supported applying for the lease of mines and quarries by the Mines and Minerals Management was simple as the applicant only have to fill Regulations of 2002 (hereafter referred as “Form B” prescribed as annex in the Regu- Regulations) are the two legal instruments lations and submit to the Department. The that governs the mining sector. For the al- Regulations provisioned that the application location of mines, the Act permits any indi- will be processed in the order in which it vidual or organization to apply for the min- was received. With the aim to become the ing lease provided the applicant is willing first applicant for a particular site, people to comply with the Act and the mining lease submitted applications without even prop- agreement; has adequate financial resources erly assessing the site and at one time there and technical competence and experience were hundreds of pending applications in to carry out mining operations effectively; the DGM. It was a burden for DGM to carry and has not been disqualified by the Gov- out prefeasibility study of all the proposed ernment to apply for a mining lease. In the sites. In general, about 70% of the applica- Regulations, however, instead of having tions get rejected during the prefeasibility supporting provisions on the eligibility reassessment which clearly shows that appli- quirement, the provision on scrutiny of ap- cations were lodged without assessment of plication refers back to the provision of the the site. For instance some applicants were Act, thus lacking clarification on the finan- not even able to locate the site they have ap- cial and technical eligibility requirement for plied. Some follow up with the DGM after different type of mines. The DGM was not decades of submission of application and able to scrutinize the incoming application still claim that they are the first applicant for and landed up entertaining all the applica- that site. Such discrepancies were mainly tions irrespective of their capabilities. The due to the limitations in the existing laws only limiting provision in the Regulations and lack of clear system and written proce- restricting a person from applying more than dure in place. two mines was also defeated when people started applying in the name of their spouse, Many mistakes were committed and the sec- relatives and others. Overall, the Act is very tor came under the scanner of the watchdog rudimentary and found to be ineffective to agencies and media. There were two rounds address many of the sector’s contemporary of performance audit on mining and related issues and challenges. The obsolescent law activities by the Royal Audit Authority. The

1 Pema Tshering, Chief Engineer, Department of Geology and Mines, Thimphu, Bhutan. Master of Environmental Management and Sustainability (Geospatial), University of South Australia. Email:[email protected]

42 | GEOSCIENCES AND MINING JOURNAL sector also came under the scrutiny of the revenue through export of minerals but to Anti-Corruption Commission followed by a generate economic activities through value study and report on business in mining, de- chain creation. The objective of the DGM picting the flaws. Mining was also a topic of is to accrue maximum benefit to the nation discussion in the National Council for few through mining development and mineral times cornering on the method of allocation industries. of the mines. The MDP encourages value addition of Mineral Development Policy minerals that are technically and economically viable, and use of minerals in local Apart from contribution to GDP, mining industries are provided with incentivized sector also generates business opportunities royalty rate to encourage investment in the like value chain, transport sector and re- development of such industries. For that duction of trade deficit through export. The very reason, during the proposal of miner- need to bring reform measures to promote al royalty revision in 2016, only the export good governance, transparency and efficient royalty was revised. service delivery was felt by many, including the private miners, and became the top pri- Global experience shows that role of the ority for the DGM. A policy was desired to government must be into framing policies, provide roadmap for the sector. The Miner- laws, rules, regulations, guidelines and pro- al Development Policy (MDP) was drafted cedures to make conducive and enabling and approved by the Royal Government of business environment. Further, the role of Bhutan (RGoB) and was formally launched government is also to regulate the sector in on May 18, 2017. Being one of the import- terms of compliance monitoring and taxa- ant sector with lots of stakeholders, the tion. To attract investment in exploration and MDP was subjected to series of consulta- mining, the government should have a geo- tion process, taking more than eight years logical infrastructures like basic geological to finalize. The DGM also had the benefit map of the country with mineral resources of international expertise through technical information at regional scale. Therefore, assistance program of the World Bank to re- it is very important that Geological Sur- view the MDP and advise on international vey must be carried out using geophysical best practices. methods (e.g. aeromagnetic, gamma ray spectrometry, remote sensing and GIS) in The MDP outlines the strategic directions to conjunction with the field geological map- manage mineral resources in a sustainable ping (e.g. geochronology, geochemistry and manner. The MDP requires the revision of litho-structural mapping). the Act, adoption of new Regulations and Guidelines, and establishment of the new The international best practice is that busi- independent Mining Regulatory Authority. ness is carried out by the private sector Such arrangements are required to optimize while government make laws and regulates the mineral resource management and real- the sector. However, Bhutan is a small coun- ize the sector as one of the potential eco- try between two giant economies and any nomic diversification. The mining sector policies must be framed carefully taking should not only be seen as a contributor of into account the economic security and sov- ereignty. In this context, the minerals that

GEOSCIENCES AND MINING JOURNAL | 43 will have wider implication on the economy of the nation, either for being scarce and important for domestic use or for being rare and high value, and having security implications are classified as strategic minerals, which is prerogative of the government. The prospecting and exploration activities for non-strategic minerals can be taken up by private firms while DGM does for strategic minerals. The DGM may also prospect and explore for other potential minerals which on discovery, can normally be allocated through competitive bidding process. Figure 1: Issuance of Mining Rights Certifi- cate and Rights Certificate Implementation of the MDP

The existing Act is rudimentary and requires revision to address many of the contemporary issues and to provide legal instrument to implement the provisions of the MDP. Therefore, DGM initiated the drafting of Mines and Minerals Bill of Bhutan (hereafter referred as Bill) in 2016.

The draft Bill is submitted to the Parliament and currently under review of Economic and Finance Committee of the National Assem- bly. The Committee shall present the third reading of the Bill in the upcoming winter session of the Parliament, 2019. Figure 2: Issuance of mining lease and permit As part of the key reforms, the Bill proposes formation of Mining Regulatory Authority Mineral Rights Cadastre, a division within (MRA) as a functional autonomy to regulate the Department with clear set of procedure mining activities. The current Mining Divi- established in the laws. The Mineral Rights sion under DGM will be delinked to form the Cadastre shall receive application and pro- MRA. There is a clear delineation of roles be- cess to issue Mining Rights Certificate for tween DGM and the MRA in the Bill, which mining and Rights Certificate for short term is necessary to separate the policy and leas- mining, fossicking, surface collection and ing, and regulatory functions which is seen artisanal mining (Figure 1). as having a conflict of interest when kept under one organization. For the purpose of The certificate holder may approach the transparency and efficiency of service deliv- MRA for signing of lease agreement or ery, the role of DGM shall be played by the issuance of permit. In the case of mining,

44 | GEOSCIENCES AND MINING JOURNAL the MRA shall ask the certificate holder to captured in the Bill. A grievance redressal prepare Mine Feasibility Study report and mechanism is also introduced through es- conduct Environment Impact Assessment tablishment of three-tier committee. (EIA), and then upon obtaining the Envi- ronmental Clearance, the lease agreement In conjunction to the Bill, the DGM has will be executed. For permits, the certificate come up with the first draft of the Regula- holder shall be made to complete the re- tions. The idea is to ready the Regulations quirement which will be spelled in the Reg- for implementation by the time the Bill is ulations and then issue the relevant permit enacted by the Parliament. Subsequently, (Figure 2). number of new guidelines will also be put in place to supplement the regulation. Some The Bill has adequately captured all the rel- of the required guidelines are as follows; evant provisions with regards to licensing exploration activities, leasing of mines and - Guidelines for Leasing Mines; permitting of short term mining, fossick- - Guidelines for Public Consultation; ing, surface collection and artisanal mining, - Guidelines for Mine Feasibility Study; including the rights and obligations of the - Guidelines for Community lessee. The objective is to allow mining to Development; all eligible and qualified applicants and then - Guidelines for Mine Reclamation stringently monitor the activities for scien- - Compliance Monitoring Tools; tific and professional mining operation. In line with the MDP, the Bills also ensures Security of tenure is very important to the equal participation of SOE’s and private promoters to ensure return of investment. sectors in mineral development. One way of securing the tenure is providing adequate lease term. Internationally, the Scrutinization of exploration and mining lease term of a mine usually ranges from 25 applicant is important because the activities - 50 years with renewal provisions. In case are capital intensive and involves technical of Bhutan, the lease of mine may be granted know-how to operate it professionally. The up to economic life of a mine or a maximum need of technical manpower for all classes of 30 years, whichever is lower. The mine of mines will be spelled out clearly in the will be renewable provided the deposit is Regulations. Many mines were observed not exhausted. running in losses due to lack of knowledge to operate them scientifically and econom- Recently, many discussions took place with ically. Such mines are also likely to cause regards to who should operate the mines, more damages to the environment. Special private or the State. In the past, the three considerations were also provisioned for en- auctioned mines excelled in operation and vironmental and social parameters to count- landed up making super profits. Factually, er balance the concerns and benefits, which they also contributed more than 50 percent includes compensatory reclamation, mine of their profits as revenue to the govern- reclamation fund, community development ment. However, opinions were expressed and benefit sharing. saying if the State runs the mines, all profit would have come as revenue to the govern- To ensure compliance to laws, adequate pro- ment. Ideologically agreeable, however, lit- visions on offences and penalties are also erature review and lessons in many nations

GEOSCIENCES AND MINING JOURNAL | 45 have proven that State is never successful Girones, E. O., Pugachevsky, A., & Walser, G. in carrying out business. The success stories (2009). Mineral Rights Cadastre. Washing- are usually short lived, which is observed at ton DC: The World Bank. the initial period of operation. Such practice Royal Government of Bhutan. (2017). Min- is a long forgone practice in developed na- eral Development Policy. Retrieved from http://www.moea.gov.bt/wp-content/up- tions. The inherent disadvantages of SOEs loads/2017/07/dgm2.pdf are mainly due to increase in bureaucratic Royal Government of Bhutan (2019). Mines and procedure, and frequent change in manage- Mineral Bill. Retrieved from http://www. ment which lacks long term planning and moea.gov.bt/wp-content/uploads/2017/07/ implementation. In many countries, ulti- Economic-Development-Policy-2016.pdf mately it had led to privatization. Litera- tures also says that corruption increases in SOEs making the company poorer and the employees richer.

In the past, the three auctioned mines are allocated with an Initial Public Offering (IPO) of 30% and the shareholders were reward- ed as high as 500% dividend in a year. To increase the broad based ownership, future auction of these mines may be required to float 49% of shares to the public. This will address the concern of few people making huge profits and is also in line with the MDP provision of providing broad based ownership of minerals.

Overall, major reforms are under taken with the sole objective to promote the mineral development to contribute to national economy by attracting investment while ensuring social and environmental considerations. These are much needed reforms to realize its full potential as one of the five jewels of the economy. The completion of reform measures are expected to boost its performance as an alternative source of revenue to achieve the economic self-reliance.

References

Girones, E. O. (2019). Development of allcoa- tion frmaework & value addition criteria and listing of strategic minerals. Retrieved from Thimphu, Bhutan:

46 | GEOSCIENCES AND MINING JOURNAL MINING CADASTRE AND ITS INTRO- DUCTION IN BHUTAN Karma Chophel1

Abstract: the extent, boundaries, and locations on the map as well as the registration procedures of land specification (cf. Shirzad et al., 2014). Efficient mineral rights cadastre has proven This system has helped to avoid potential to be vital element for any country to de- duplication or overlapping of properties. velop mining sector to its utmost potential. A similar system was adopted in mining Such a cadastre, when well developed and sector, though it came into existence much backed by capable public mineral man- later than the land. Management of mineral agement agencies, integrates the regulato- rights became necessary as soon as mining ry, institutional, and technological aspects was commercialized. This evolution, which of mineral rights administration and leads probably began in the Bronze Age, was good mineral resources management in later spread by the Phoenicians around the a country. It is high time that Bhutan also Mediterranean Basin and first recorded in adopts mineral rights cadastre system to Greece, where, by 500 B.C., an early ver- improve good governance and attract in- sion of today’s modern mining cadastres vestment by ensuring security of tenure and was already operating, distributing mining promoting transparency. In this respect, the royalties among the citizens of Athens (Gi- mining cadastre is introduced in the Mines rones et. al., 2009). and Minerals Bill 2019 and will become effective upon its enactment. The article is intended to create understanding of princi- 1.2. The modern day mining ples, legal and institutional framework, and cadastre application of mining cadastre. In the present day, the mining cadastres have become public institutions with the ex- 1. Introduction clusive responsibility for managing mineral rights and leases in a country, integrating 1.1. Origin of Cadastre concept the regulatory, institutional, and technological aspects of mineral rights administration. The term Cadastre originated from adoption The cadastre function is not only limited of a system to help manage issues related to to maintaining of record and data such as the private ownership of properties especial- maps, registries, archives, files or computer- ly land to ensure the security of ownerships ized systems (Girones, 2019). Today, it has and establish taxation units for the country. become an important administrative unit The International Surveying Federation has which has an institutional mandate for the defined Cadastre as a regulated system of management of mineral rights. Some of the properties that defines all data related to principles to ensure effective and efficient

1 Karma Choplel, Executive Engineer, Department of Geology and Mines, Thimphu, Bhutan Master of Professional Engineering, The University of Western Australia, Email:[email protected]

GEOSCIENCES AND MINING JOURNAL | 47 granting procedures according to Girones et al. (2009) are:

• The efficient functioning of a cadastre relies on: A clear legal and regulatory framework; • Well-defined institutional responsibilities; and • Transparent and non-discretionary processes.

1.3. Importance of cadastre in mining industry

Mineral rights is the cornerstone of mineral resources management in any country, which Figure 5: Impacts of poorly functioning mineral cadastre (Source: Centre for Energy is demonstrated by international experienc- Petroleum and Mineral Law and Policy) es (Girones et al., 2009). A poorly-functioning mineral cadastre can potentially deter investors and increase speculative practices, resulting in prospective land being withheld following core principles of mining cadas- from exploration and ultimately leading to tres: a decline in revenue contributions from the mineral sector, as shown in the Figure 1. • Mineral resources belong to the state; • The right to explore and exploit min- The Mining Cadastre System is often per- eral resources may be temporarily ceived as equally important to the Mining transferred to an individual or a cor- Law. It is therefore, critical to have an ef- porate entity through a written doc- ficient cadastre system that enhances in- ument, normally called a license or vestor’s confidence in the sector. For the lease or permit; Government, an efficient Mining Cadastre System provides the strategic directions for formulation of policies, Mining Laws, sys- Mineral rights are distinct from surface or tematic management of the sector (Feast land ownership rights; et.al., 2005). • The granted licence or lease or permit 1.4. Core principles of mining usually does not include visible phys- cadastre ical boundaries (such as fencing). In- stead, the area is usually delineated In most countries, mineral rights have the by geographic references or coordi- same status as real estate properties. How- nates; ever, there are several key differences be- • The holders of the granted licence or tween standard land or soil properties and lease or permit must fulfil pre-estab- mineral rights. Girones, 2019, outlines the lished conditions to be granted and maintain their rights over the area;

48 | GEOSCIENCES AND MINING JOURNAL • When the validity of the granted li- In the Bhutanese context, the Constitution cence or lease or permit ends or ex- clearly spells out the general principles and pires, the rights return to the state; the mineral rights. Article 1(12) of Consti- • The licence or lease or permit of the tution of the Kingdom of Bhutan states “The mineral right cannot be suspended or rights over mineral resources, rivers, lakes revoked except on specific grounds. and forests shall vest in the State and are These must be objective and non-dis- the properties of the State, which shall be cretionary. They should be clearly regulated by law.” The existing mining law specified and detailed in the legal in force “Mines and Minerals Management framework; and Act” was passed in 1995 by the parliament • In some countries, mineral rights are session of prodemocracy form of the gov- divided into exploration and mining ernment and its regulation, the “Mines and licences. Minerals Management Regulation” was approved for implementation in 2002. The act In the Bhutanese context, the core principles and regulation have provisions on explora- mentioned above applies and future mining tion and geoscientific activities, functions policy and laws need to gear towards imple- and roles of agencies responsible for min- menting these principles. eral management, rights and obligations of lessee and permit holder, access to minerals 2. Mineral Rights resources, social and environmental consid- Management erations, and fiscal terms. The Mineral Development Policy 2017 pro- 2.1. Legal Framework vides the road map for the sector to contribute in achieving national goal of economic Generally, the mineral ownership and le- self-reliance by promoting sustainable de- gal basis for mineral exploration and min- velopment while ensuring social considering is enshrined in a constitution. Sectoral ation and environmental stewardship. The laws are approved by the Parliament. Oth- policy also addresses some of the contem- er provisions, such as those that may need porary issues related to the sector like ben- periodic adjustments (such as technical re- efit sharing, community participation and quirements, administrative procedures, and development, and has incorporated some of administrative fees), are typically set in the the international best practices. The Mines regulations. The sector laws and related reg- and Minerals Bill 2019 has been drafted to ulatory framework will be most effective if implement these policy directives by trans- they reflect the government’s key policy deforming policy statement into a law. The cisions considering a good level of knowl- Bill also introduces Mineral Rights Cadas- edge on geology and minerals resources. A tre to promote transparency and account- well-defined sector law usually includes the ability, improve service delivery and attract role of the state, security of tenure, rights investment. The Bill is submitted to the Par- and obligation of licence or permit holder, liament for enactment. access to mineral resources, comprehensive social and environmental protection requirements, and competitive fiscal terms (Girones et al., 2009).

GEOSCIENCES AND MINING JOURNAL | 49 2.2. Security of tenure 2.3. Granting overlapping licences Generally, security of tenure is the legal protection assured to the tenants, to use In some countries, holders can obtain over- the properties that is rented from the own- lapping exploration licences, with each li- er’s legal right. Mining investments are cence valid for a different minerals. The risky. For instance, only one out of 1000 ex- benefit of such practice is to promote si- ploration projects are likely to be successful multaneous exploration for different types (Kreuzer & Etheridge, 2010). Security of of minerals. However, it has serious diffi- tenure is therefore, particularly important culties, because two or more minerals are in mineral rights. In most countries, mineral frequently present in the same deposit or rights are divided into exploration licenc- hosted in the same rock, making separate es and mining leases. Exploration licences exploitation impossible. give holders the right to explore and evaluate the economic exploitation of any min- For this reason, in countries where an over- eral resource that potentially exist within lap is allowed in exploration licences, it is the granted area. If an economic resource is normally prohibited for mining licences. confirmed, the exploration licence may be Only the first holder (from among several converted into a mining licence. It is during overlapped licences) applying for the trans- this transition that risks may arise. formation of a licence from exploration to mining has the right. This approach makes Security of tenure must be attractive to at- exploration riskier for the licence holder of tract investments for mineral exploration. overlapping leases, because the basic prin- For instance, investment in exploration can ciples of discoverer rights are not respected, be boosted by ensuring mining rights after thus affecting security of tenure(Girones et investing in exploration. This is normally al., 2009). However, negotiation between provided through two principles (Girones, the parties for amalgamation of licences 2019) which should be clearly established through joint venture may be allowed. in the legal and regulatory framework and are as follows: In Bhutan, overlapping of prospecting licence for different minerals at a particular • The titleholder of an exploration li- location can be permitted. However, over- cence has the exclusive right to apply lapping of exploration licence in a particu- for a mining lease in the demarcated lar location will not be permitted to ensure area by the exploration licence; and security of tenure. • The titleholder of a mineral right has exclusive rights to any mineral dis- 2.4. Reinforcing security of covered inside the demarcated area. tenure However, in case of Bhutan, MDP empha- Given the importance of security of tenure, sizes on categorization of strategic minerals some governments take additional measures and the allocation right being the preroga- to reinforce the right, with a view to increas- tive of the government. Other than strategic ing sector’s attractiveness for investors. Ad- minerals, all minerals follow general princi- ditional measures suggested by Girones ples as described above. (2019) are:

50 | GEOSCIENCES AND MINING JOURNAL • Allowing licence holder to automati- 3. Institutional Framework cally renew exploration licences, pro- for Minerals Rights vided the licence holder has fulfilled the required conditions; Cadastre • Allowing licence holder who fulfil their responsibilities during explo- A basic principle applied in successful min- ration phase to be granted automatic ing economies are development of a strong rights to the mining lease in the same institutional framework. The main functions area; and of public mineral management agencies in- • Granting a single licence for both ex- clude: (i) development of sector policy, ploration and mining, which avoids goals, and strategies; (ii) establishment of the need to convert an exploration li- the legal and fiscal framework, including cence to a mining licence guarantees the formulation of regulations and guide- the rights of the exploration entity. lines; (iii) administration and monitoring of compliance with all laws, regulations, and 2.5. Mining lease term procedures; and (iv) establishment of database and accessible websites containing re- Mining rights should be given for a suffi- liable technical information for monitoring ciently longer period of time and be renew- sector performance, land use management, able until exhaustion of the reserve of the and sector promotion. mineral. In general, mining rights are granted for a period ranging between 25 and 50 years, and are renewable once or several times (Girones et al., 2009). The termina- tion of a mining right at the end of an arbi- trary period may have unintended negative consequences, discouraging reinvestment and forcing mine closure even when a deposit can be economically mined. For this reason, some countries do not have terms for mining rights; they last for as long as the holder continues to comply with the appli- cable requirements. Figure 2: Most common set up of public mineral management agency (Girones et al., 2009) The MDP recognizes the importance of the longer lease term and therefore, proposes An efficient and effective mineral manage- for lease up to maximum of 30 years and ment agencies call for institutional separa- renewable until exhaustion of the reserve tion between administrative responsibility upon fulfillment of lease conditions. A pro- for granting mineral licences, control of gressive fiscal regime need to be considered mining activity, and generation of geolog- to ensure a right balance between security of ical knowledge-base. These functions are tenure and benefits sharing to the state and complementary, but practical experience community. shows that the system is more efficient and the risk is lower for the investor if they are undertaken by separate agencies. The Fig-

GEOSCIENCES AND MINING JOURNAL | 51 ure 2 shows the most common organization- ter. Some basic prerequisites which need to al structures of public mineral management be considered while adopting those organi- agencies and their functions. zational structures are as follows:

Generally, the ministry responsible for • To support coordination between the mines acts as the political head of the sector. cadastre and other agencies focused The responsibility of ministry include; for- on geological infrastructure, control mulation of mining policy and laws and reg- and inspectorate, all should be linked ulations; coordination with other ministries; to the ministry responsible for the supervision of the mining sector agencies/ management of the mining sector; offices responsible for implementing policy • To avoid technical interference and and compliance with regulations; compila- unnecessary operational interactions, tion and publication of statistical data; and the cadastre should be hierarchical- ly independent from the Geologi- promotion of exploration and mining activi- cal Survey and mining inspectorate ties, and investment opportunities. agencies, regardless of the need for coordination; and The Mineral Rights Cadastre (MRC), as a • To guarantee objectivity, transparen- public sector entity, receives applications cy, equity, and fairness in decisions and issues and administers mineral rights. affecting the granting of mineral rights and avoid conflict of interest, The Geological Survey develops and main- the cadastre should be independent tains reliable national earth science infra- from any State Owned Enterprises. structures, including geological maps and related database. It also provides basic geo- The present management of the mineral sec- logical knowledge for the mineral industry tor in general and the licensing activities in and other needs such as water resource man- Bhutan are far away from the internation- agement, environmental management, land al standards (Girones, 2019). Some of the use, geo-hazards risk management, and civil important problems detected in the manage- works. ment of the mining sector and the allocation of the mineral rights are closely related to The Mines Inspectorate monitors mining the inadequate institutional organization, operations and ensures compliance with the ambiguous regulatory framework, the laws, regulations, and procedures related complexity of the procedures and the lack mostly to environmental, social, health, and of the adequate equipment. Currently, there safety issues (Girones et al., 2009). are multiple division under the Department involved in processing of mining applica- Different countries around the world have tion. The provision for establishment of adopted a variety of organizational solu- Mineral Rights Cadastre Unit under DGM tions to administer mining cadastres. In is introduced in the Mines and Minerals some countries, the MRC is an independent Bill 2019, which will mandate the Unit to department inside the ministry or state insti- maintain mineral cadastre and process ap- tution responsible for the mining sector. In plications for grant of Mineral Rights. For others, the MRC is an agency external to the e.g. to enhance transparency, new reforms ministry but reporting directly to the Minis- such as maintaining separate register for

52 | GEOSCIENCES AND MINING JOURNAL mining application and issuance of certifi- bids for granting, when required; and cate acknowledging receipt and registration • Collecting administrative fees and of applications are initiated. Further, Min- annual rental fees. ing Regulatory Authority (MRA), an auton- omous regulatory body, will be established Consistent with these functions and duties upon enactment of the Mines and Mineral and the need for institutional separation, the Bill 2019. The MRA will be delinked from mineral rights cadastre SHOULD NOT: DGM and will take up the function of Mines Inspectorate. • Take care of geological and metallo- genic information; 3.1. Mandate and functions of a • Develop control activities related to Mineral Rights Cadastre the technical aspects of mining, ore processing or production; Girones et al. (2019) outlines the following • Monitor health, safety or environ- primary roles and responsibilities of MRC: mental impacts; • Be responsible for setting and collect- • Receiving applications for new pro- ing royalty payments; and posals, as well as requests for renew- • Evaluate technical, production or en- al, extension, reduction, transfer, and vironmental reports. abandonment, and initiating procedures for the revocation, cancellation, 4. future works or expiration of licences or leases or permits; The details on Mining Cadastre, method of • Evaluating proposals and making de- granting mineral rights, best practices and cisions to grant or refuse them; technical aspects of the minerals rights ca- • Liaising between the state and licence dastre will be covered in the next edition of holders or applicants on any question Geosicences and Mining Journal. related to mineral rights; • Chronologically recording new appli- References cations in an official registry; • Producing updated cadastral maps on Centre for Energy Petroleum and Mineral Law which existing mineral rights, pend- and Policy, U. o. D. Mining Cadastre and ing applications, and areas restricted Licensing. Retrieved from https://www.ex- for mining activities are correctly tractiveshub.org plotted; Royal Government of Bhutan. (2008). The Con- • Verifying that licences do not over- stitution of the Kingdom of Bhutan. lap; Feast, B., Davids, J., Mills, T., & Devries, P. • Keeping cadastral maps and regis- (2005). Mining Cadastre in Africa – Les- tries open and accessible for public sons Learnt Paper presented at the 5th FIG Regional Conference for Africa : Promoting consultation; Land Administration and Good Governance, • Acting as a technical referee in dis- Accra, Ghana. putes between holders about the loca- Girones, E. O. (2019). Development of allcoa- tion of areas granted; tion frmaework & value addition criteria • Organization and execution of tender and listing of strategic minerals. Retrieved from Thimphu, Bhutan:

GEOSCIENCES AND MINING JOURNAL | 53 Girones, E. O., Pugachevsky, A., & Walser, G. (2009). Mineral Rights Cadastre. Washing- ton DC: The World Bank. Kreuzer, O. P., & Etheridge, M. A. (2010). Risk and Uncertainity in Mineral Exploration: Implication for Valuing Mineral Exploration Properties. Mineral Economics AIG News No. 100(May 2010), 20-28. Shirzad, M., Babaie, H., Kiani, T., Navi, M., Gholami, H., Arefipour, S., . . . Motevali, K. (2014). Framework and modeling structure of Exploration and Mining Cadastre system in Iran. Earth Science Informatics, 7, 123- 138. doi:10.1007/s12145

54 | GEOSCIENCES AND MINING JOURNAL VALUE ADDITION OF MINERALS Nima Yoezar1

The value addition of minerals before ex- Table 1: Some of the value added mineral port is one of the priority objectives of products. Royal Government to accelerate economic Minerals Value added products development through creation of econom- Plaster of Paris (PoP) ic value chain, employment and industrial Gypsum Chemical fertilizers development from its largely unexploited Board products mineral resources. Value addition brings Refractory bricks massive benefits in terms of employment Dolomite Paints creation and growth in minerals export val- Magnesium metal ue which directly translates to increased tax Cement returns. The increase in domestic demand Precipitated Calcium Carbonate for goods and services and infrastructure (PCC) developments are other secondary benefits Limestone Ground Calcium Carbonate of in-country value addition. (GCC) AAC Block As per Mineral Development Policy (MDP) Wall putties Carbon paper 2017, value addition is defined as ‘products Graphite of mineral beneficiation and processing Ion Batteries covering the whole range of processes from Ferro-silicon Quartzite basic ore dressing, such as crushing and Glasses screening, through to the manufacturing of semi-final/final consumer goods or - chemi Policy Interventions for Value cally altered products.’ Addition To fulfill this objective, Department of Ge- Beneficiation of minerals in Bhutan is sup- ology and Mines (DGM) strives to promote ported by number of provisions within ex- in-country value addition by discouraging isting national policy and legislation such the export of minerals in raw form. Current- as the Economic Development Policy 2016, ly, in-country value addition is limited to Minerals Development Policy 2017, For- production of Cement, Wall putty, Chicken eign Direct Investment Policy 2019 and Fis- feeds and steel production. cal Incentives Act of Bhutan 2017. Further, the Mines and Minerals Bill 2019 has also provisioned for promotion of in-country value addition.

1 Nima Yoezar, Senior Program Officer, Department of Geology and Mines, Thimphu, Bhutan PG Diploma in Public Administration, Royal Institute of Management. Email:[email protected]

GEOSCIENCES AND MINING JOURNAL | 55 Economic Development Policy companies that invests in in-country value 2016 addition.

The Economic Development Policy outlines Foreign Direct Investment the economic roadmap and highlights the Policy 2019 priority sectors for economic growth and investment. Due to its high economic poten- The Royal Government of Bhutan has tial, mining sector has been categorized as opened up the economy to Foreign Direct one of the five jewels of Bhutanese econ- Investment through adoption of FDI Policy omy along with hydropower, tourism, ag- in 2002. Since then the policy has under- riculture, and cottage and small industries. gone three major revisions in 2010, 2014 In order to benefit from close geographical and 2019 respectively liberalizing the in- proximity among industries that are linked vestment regime by expanding the econom- by commonalities and complementarities, ic base, employment generation, foreign the policy guarantees designation of indus- exchange earnings and revenue generations. trial areas in a cluster approach. Further, The FDI Policy 2019 guarantees equal treat- EDP also mandates the development of as- ment, repatriation of dividends, repatriation sembly line production system in order to of capital, freedom of disposal, and intellec- promote manufacturing sector in the coun- tual property rights to foreign investors. The try. policy also allows FDI company to invest a minimum project cost of Nu. 50 million and Mineral Development Policy own foreign investors equity shareholding 2017 up to 74% in production and manufacturing industries thereby securing tenure and providing investor-friendly environment. The Mineral Development Policy (MDP) The policy discourages investment of FDI 2017 envisages the mining sector to play an in mining activities without value addition important role in future growth of economy projects and sale of minerals in primary or and in meeting our national goal of eco- raw form is under negative list. nomic self-reliance by promoting in country value addition and modern scientific mining methods. The policy encourages a re- Fiscal Incentives Act of Bhutan source-based industrialization for all viable 2017 and potential minerals. The policy statement requires all mining companies to carry out The fiscal incentives refers to temporary in-country value addition for all viable min- exemption of taxes and duties or granting erals and curtail export of raw materials in income tax holidays for boosting private primary form. Further, the policy guarantees sector development and attracting foreign facilitation for development of mineral val- direct investment to achieve broader eco- ue chain to promote economic growth and nomic development goals. The Fiscal Incen- achieve intergenerational equity. With an tives Act of Bhutan 2017 provides income objective to accrue maximum benefits the tax holiday up to 10 years for newly estab- government has incentivized in-country val- lished company and 5 years for existing ue addition through number of policy provi- domestically sourced mineral based indus- sions that ranges from priority allotment of tries meeting the value addition criteria pre- captive mines to levy of lower royalty to the scribed by competent authority. Such incen-

56 | GEOSCIENCES AND MINING JOURNAL tives will play a pivotal role in a developing economy with limited domestic productive capacity to diversify the economy. Further, the Rules on Fiscal Incentives Act of Bhutan 2017 exempts Sales Tax & Custom Duty on equipment & machineries for mining industry. It will help to promote scientific mining and foster the growth of local industries, and sustain the business as the companies Figure 1: Value added products of Dolomite would enjoy tax exemption for import of Bricks (Source: TRL Krosaki Refractories any equipment & machineries for establish- Ltd.) ment of mining industry.

Mines and Mineral Bill 2019

The Mines and Minerals Bill of Bhutan 2019 submitted to the National Assembly was introduced in the second session of the Third Parliament and completed its the second reading. The Bill imposes a person/ company to add value on the mineral before export where it is technically and economically viable. Such provisions would ensure companies to invest for in country mineral industrialization, which would lead to enhanced economic opportunity and benefit to Figure 2: Paper made out of limestone, the nation. (Source: https://www.stone-paper.com/en/ stone-paper-the-environment-friendly/) The inhibitive factors to effective implementation and development of the value ad- Infrastructures: shortages of critical and dition programs in Bhutan are diverse and cheap transport infrastructures such as rail- not limited to the following: way and riverine connectivity have an adverse impact on attracting and sustaining Industries for local beneficiation: the cur- in-country beneficiation initiatives, and is rent structural arrangement of the mining construed as a major threat to future pros- industry in Bhutan remains geared towards pects and growth in value addition pro- export in raw form to neighbouring coun- grams. In order to reap the benefits of rich tries. Government’s intervention to provide mineral endowments, long term investment incentives and create a conducive environ- in the development of such basic infrastruc- ment for setting up of beneficiation plants tures connecting international markets are are first few steps to realize the long term necessary. goal of sustaining value addition industries in the local market which would generate Research and Development: Bhutan’s lim- employment and downstream business op- ited exposure to break-through research and portunities.

GEOSCIENCES AND MINING JOURNAL | 57 development programs for in-country value addition deters the prospects of innovation in creating new products in the local market. R&D is critical for production of materials of high purity for use in advanced technology applications such as semiconductors, photo-voltaic cell, special sensors, hard and high temperature materials, superconduc- tors, insulators, glasses, etc. The coordination, synergy and convergence among the various government institutions (including educational and vocational institutes) en- Figure 3: Limestone usage in cement production (Source: https://www.dccl.bt/?page_id=95 gaged in R&D is critical to derive the maximum benefit.

Accessibility to international markets: Bhutan being land locked mountainous country has an inherent disadvantage to access the international market for import of raw materials and export of finished goods. It is further aggravated by small work force and small scale of economy. Therefore, Bhu- Figure 4: Dolomite in paint industry, tan has to adopt strategic policies in order to Source: https://bandhancalchem.com/dolo- be competitive in the international market. mite-in-paint-industry.php Further, it is crucial for the government to provide incentives and lower power tariffs to reduce the production costs of those products that are manufactured in the country.

Reference

Chen, L. and Dick A. W. (2011). Gypsum as an agricultural amendment: General use guidelines. The Ohio State University, US. Figure 5: Gypsum board product (Source: Royal Government of Bhutan. (2016). Eco- detailed feasibility analysis of gypsum boards nomic Development Policy. Retrieved from & panels – ceiling & insulation) http://www.moea.gov.bt/wp-content/uploads/2017/07/Economic-Development-Pol- loads/2017/07/FDI-Policy-2019.pdf icy-2016.pdf Royal Government of Bhutan. (2017). Min- Royal Government of Bhutan. (2017). Fiscal eral Development Policy. Retrieved from Incentives Act of Bhutan. Retrieved from http://www.moea.gov.bt/wp-content/up- https://www.mof.gov.bt/wp-content/uploads/2017/07/dgm2.pdf loads/2018/01/FIAB2017.pdf Royal Government of Bhutan (2019). Mines and Royal Government of Bhutan. (2019). Foreign Mineral Bill. Retrieved from http://www. Direct Investment Policy. Retrieved from moea.gov.bt/wp-content/uploads/2017/07/ http://www.moea.gov.bt/wp-content/up- Economic-Development-Policy-2016.pdf

58 | GEOSCIENCES AND MINING JOURNAL THE MIDDLE PATH : STRATEGIZING ENVIRONMENTAL COMPLIANCE IN MINING IN BHUTAN Sangay Dendup 1, Karma Chophel 2, Nima Yoezar3

Introduction it can also have adverse social and environmental consequences. In addition to The Bhutanese people and the environment Bhutan’s stringent environmental laws, the enjoys a close relationship practiced over Mineral Development Policy (MDP) 2017 the centuries in relation to cultural and re- stresses on strengthening the importance of ligious significance. The traditional and lo- environment in the mineral development cal beliefs promoted the conservation for with special focus on impact assessment environment, and key ecological areas were and post mining reclamation. recognized as the abodes of gods, goddess- es, protectives deities and mountain, rivers, The mining sector makes significant contri- forest and underworld spirits (National En- bution to the nation building through reve- vironment Commission, 1998). Further, the nue generation, business and employments country’s development philosophy, Gross opportunities. The generic environmental National Happiness (GNH) emphasizes the impact of mining includes dust, water and importance of environmental conservation, noise pollution, and land degradation. while undertaking socio-economic development. The Article 5 of the Constitution of Environmental Impacts the Kingdom of Bhutan further strength- ened the importance of empowerment by Environmental impacts of mining can occur mandating protection of environment as the at local, regional, and global scales through fundamental duty of every citizen. direct and indirect mining practices. Some of the common environmental impacts are; The Economic Development Policy (EDP) 2016 further emphasizes the economic de- Impact on Biodiversity velopment should be streamlined by main- streaming environment in a phased manner The mining activities require removal of that allows for industries to grow as well as vegetation and disturbances on land and engage in cleaner production. ecosystem while undertaking site development and during actual mining operation. While mining activities result in increased economic opportunities and development,

1 Sangay Dendup, Mining Engineer, Department of Geology and Mines, MoEA, Thimphu, Bhutan Email: [email protected] 2 Karma Choplel, Executive Engineer, Department of Geology and Mines, Thimphu, Bhutan Master of Professional Engineering, The University of Western Australia, Email:[email protected] 3 Nima Yoezar, Senior Program Officer, Department of Geology and Mines, Thimphu, Bhutan PG Diploma in Public Administration, Royal Institute of Management. Email:[email protected]

GEOSCIENCES AND MINING JOURNAL | 59 Air Pollution Ground Vibration

Currently, minerals mined in Bhutan con- Blasting is the cheapest methods of rock stitutes industrial minerals and construc- breaking and sizing. Except for some min- tion stones. Most of these minerals are not erals, blasting is a mandatory operation for known to possess toxic contaminants that extraction of minerals. Blasting generates has direct implication to the health. Howev- ground vibration and air blast, which can er, operation of mines generate dust which cause structural damages. The unplanned makes the surrounding dusty and unpleas- and uncontrolled blasting may cause signif- ant for settlement. Dust is produced due to icant damages to the properties and liveli- drilling and blasting practices, breakage of hood of communities residing proximity to rocks by rock breaker, and plying of dumper the mine. and machinery. Such dusts, if not mitigated properly, can be a potential cause to respira- Environment Laws tory and cardiovascular health problems due to inhalation of particulate matters. The old environment laws of the Kingdom of Bhutan were mainly focused towards Noise Pollution conservation of forests and protection of wild life habitat. It include Forest Act 1969, Drilling, blasting and use of heavy earth and Forest and Nature Conservation Act moving machineries in the operation in 1995. The recent environmental laws were mines are the major source of noise pol- enacted with a greater emphasis on environ- lution. Screening and crushing plants also mental principles, middle path strategy and have a significant contribution to the noise inter-generational equity and polluters pay pollution. principle. These include Environment As- sessment Act 2000, National Environment Water Pollution Protection Act of Bhutan 2007, The Water Act of Bhutan 2011 and Waste Prevention Since mining in Bhutan is limited to indus- and Management Act of Bhutan 2009. The trial minerals and construction stones, major compliance to all these environmental laws water pollution such as acid mine drainage, is mandatory for any developmental activi- heavy metal contamination and leaching, ties including mining. and processing chemicals are insignificant. However, erosion and sedimentation are The National Environment Commission, some of the water pollutions from mines, which is an independent authority, is the quarrying and overburden dumpsites. Ex- highest decision-making body on all the cessive sedimentation can cloak river beds matters relating to the environmental man- and smother vegetation, wildlife habitat and agement in the country. The Secretariat un- aquatic organism. Planning, prevention and der the Commission is the agency, which is- control strategies has been a major chal- sues environment clearance to the projects, lenge given steep topography and erratic and monitors and controls compliance with rainfall pattern during monsoon. terms of environmental clearances.

60 | GEOSCIENCES AND MINING JOURNAL Environmental Clearance security for mine reclamation and environmental restoration. The payment of ERB The Environmental Clearance (EC) is a pre- does not exempt the miners from carrying requisite to the lease of mines. To obtain the out environmental management activities in EC the mining project has to conduct Envi- line with EMP. The ERB is refundable if the ronmental Impact Assessment (EIA) in line miners adhere to the obligation of post min- with the EA Act 2000 as per the Regulation ing reclamation. However, failing to carry for Environmental Clearance Project 2016. out the reclamation, the government shall The EC of the projects details out the envi- forfeit the ERB and the same will be used ronmental terms and conditions. for reclamation of the mine.

Mining Laws ERB Fund Estimation Formula

Any mining projects requires Final Mines The method of calculating ERB shall be Feasibility Study (FMFS) which includes based on the surface area coverage, over- Mine Plan, Environment Management Plan burden waste reflected in the FMFS report (EMP) and Mine Restoration Plan (MRP). and the actual production of mineral. The These plans are approved by DGM after formula is as follows: meeting all the technical requirements and environmental standards. The EMP consist ERB = Ax + By + Cz of baseline data, anticipated impacts and all the mitigation measures for each component Where, of the environment impacts that are likely as a result of mining activities. The EMP A = Surface area (Hectare) B = Overburden/inter-burden is prepared in line with Mines and Miner- 3 al Management Act (MMMA) 1995 and waste (m ) Mines and Minerals Management Regula- C = Production (MT) tion (MMMR) 2002. DGM ensures the implementation of EMP to ensure compliance The surface area shall be the total demarcat- with environmental standards and terms of ed mining area by the DGM. environmental clearance. The value of x shall be:

Planning of post mining reclamation starts - Nu. 50,000/hectare for all talc mines from the beginning of the mine life by sub- - Nu. 20,000/hectare if surface area is mitting MRP along with the FMFS report. < 10 hectares Such report ensures progressive reclama- - Nu. 15,000/hectare if surface area is tion leading to minimal reclamation after >10 but < 20 hectares the closure of mine, which is economically - Nu 10,000/hectare if surface area is > beneficial to the miners. 20 hectares

Environmental Restoration Bond The value of y and z shall be Nu. 5 and Nu. 4, respectively. The values of x, y and z shall The miners are required to deposit an en- be subjected to revision from time to time vironmental bond to the government as a to cover up the cost of inflation and other reclamation cost.

GEOSCIENCES AND MINING JOURNAL | 61 Mode of collection During the construction and developmental stage, the miner should preserve the The ERB amount from surface area and topsoil at pre-identified area for use during overburden waste (Ax+By) is payable prior reclamation at the end of mining life cycle. to the commencement of operation of the Clearing of vegetation is carried out only af- mine. The ERB amount from production ter approval from Department of Forest and (Cz) is payable on the actual quantity of Park Services. Dumping of overburden is mineral dispatched in advance. allowed only in the approved site.

Policy Reforms in To minimize the soil erosion and spillage of overburden that leads to water pollution, the

Environmental Management mines operators are required to construct retaining walls and other appropriate mea- MDP 2017 aims to promote environmental sures. Waste should be dumped and com- friendly mineral industry through scientif- pacted properly to prevent overflow and ic mining and development in consonance erosion. Miners are also required to deploy with social and economic policies of the water sprinkler to suppress the dust. As per country. Some of the policy directives in- the existing laws, there is certain permissi- cludes adoption of risk-based approach in ble limit for dust and noise, which mining preparation of environmental studies, as- companies are required to comply with. sessment and management, and mitigation plans. MDP 2017 also emphasizes on im- The noise from blasting can be reduced by proving the mine closure and reclamation to controlled blasting and use of noise con- ensure that the mined-out area is suitable for trolled drilling machineries. Ground vibra- future land use by the community. In order tion due to blasting can be reduced by delay to ensure optimal use of the ERB, the con- or sequential timer blasting or optimizing cept of Mine Reclamation Fund has been explosive charges per blast hole. introduced. This scheme will enable utiliza- tion of the fund while reclaiming rather than being eligible for refund after completion of Mine Reclamation Guidelines reclamation, which is advantageous to miners. Reclamation is the process to produce a landscape that is safe, stable and compati- ble with surrounding landscape and final Common Good Practices for land use. While each mine sites have its Environmental Management own unique characteristic depending on its Implemented in Mines in location, there are principles that are appli- Bhutan cable to all mining operation and serve as foundation for planning and implementing Planning for environmental management reclamation plans. In this regard, DGM is and mitigation of impact is done at a source, in the process of drafting Mine Reclamation medium and receiver’s end. Measures to Guidelines to provide technical guidance, prevent and reduce at all the levels are de- ensure proper planning and successful rec- tailed in EMP. lamation and closure of mine.

62 | GEOSCIENCES AND MINING JOURNAL Some of the activities that have to carried land-use, climatic conditions, growing sea- out during mine reclamation are: sons and the surrounding habitats.

Planning for Reclamation Site Monitoring and Maintenance

A Mine Closure and Reclamation Plan It is important to nurture the planted sap- (MCRP) shall be prepared by the miners lings to ensure proper growth and its sur- with a clear objective for reclamation and vival. The aftercare of the plantations shall final land-use in consultation with the com- be carried out for a minimum of two years munities and land users. The miners are also subject to the proper growth, which can sus- required to consult with ecological experts tain of its own. Further, it is also important with regard to types of plants and trees to be to monitor the slope stability conditions and used for revegetation. provide timely remedial measures.

Removal of Infrastructures Mine Closure

The miner shall remove all the temporary The obligation of the miners is fulfilled only and permanent manmade infrastructures lo- upon acceptance of reclamation by DGM. cated within the mine or surrounding areas, The mine will be formally closed only upon which are redundant to the community. issuance of Form O of MMMR 2002 by DGM. The performance of the miners on Landscaping and Slope Stabilization reclamation impacts his eligibility for application of new mine in future. Landscaping design or re-shaping topography of the mine site is an essential aspect Reference of reclamation plan to ensure proper growth of plants and modify the visible profile of Australian Government. (2006). Mine Rehabil- post mine area. Further, slope stabilization itation. Retrieved from https://www.im4dc. is critical to prevent mining and overburden org/wp-content/uploads/2014/01/Mine-reha- bench failure, and soil erosion. Some of the bilitation.pdf slope stabilization technique may include National Environment Commission (1998). construction of retaining walls, drainage, The Middle Path, National Environment st bio-engineering, etc. Strategy,1 edition. National Statistics Bureau. (2018). Statistical Yearbook of Bhutan. Revegetation Norbu, D. (2013). Mining has great economic potential for Bhutan. Retrieved from https:// Revegetation of disturbed or excavated land thebhutanese.bt/mining-has-great-econom- surface is essential for effective and suc- ic-potential-for-bhutan/ cessful reclamation and slope stabilization. Royal Government of Bhutan. (1969). Bhutan The planning of revegetation requires a Forest Act. Royal Government of Bhutan. (1969). Forest knowledge of pre-existing conditions and a and Nature Conservation Act. target for long term integrity of the system. Royal Government of Bhutan. (1995). Mines This also requires perspective on desirable and Minerals Management Act. Royal Government of Bhutan. (2000). Environ-

GEOSCIENCES AND MINING JOURNAL | 63 mental Assessment Act. Royal Government of Bhutan. (2002). Mines and Mineral Management Regulations. Royal Government of Bhutan. (2007). National Environment Protection Act. Royal Government of Bhutan. (2008). The Con- stitution of the Kingdom of Bhutan. Royal Government of Bhutan. (2009). Waste Protection and Management Act of Bhutan. Royal Government of Bhutan. (2016). Economic Development Policy. Royal Government of Bhutan. (2017). Mineral Development Policy. Sinha, R. K. (2016). Overview on Reclamation and Rehabilitation of Mines. Retrieved from https://mines.gov.in/writereaddata/Upload- File/overviewon1.pdf Tshering, L. (2019). State of the Nation.

64 | GEOSCIENCES AND MINING JOURNAL Mining Sector at a Glance Sangay Dendup 1

Brief History of Mining in The Geological Survey of Bhutan was es- Bhutan tablished in 1981 and later, it was upgrad- ed to Department of Geology and Mines (DGM) to carry out the geological mapping, Over the history, Bhutanese have been quar- mineral exploration, other geoscientific ac- rying construction material for building tivities and manage mining. The department of houses and other structures. The use of is supported by seven regional offices viz. construction materials by Bhutanese is not Thimphu, Wangdue, Gelephu, Samdrup known but the practice is limited to use of Jongkhar, Samtse, Gomtu and Phuentshol- manual tools and labors. History records ing, mainly for inspection and compliance that initial mining of metals started when monitoring of the mines. Dupthop Thangtong Gyalpo alias Chak- zampa visited Bhutan, smelted iron ore and To manage the geo-scientific activities and produced iron chains to build suspension mining, the first mining law, Mines and bridges in fifteenth century (CBS, 2007). Minerals Management Act (MMMA), was But the modern day mining with machiner- enacted in 1995. Subsequently, the Act was ies began only in the early 1980s with the supplemented by Mines and Minerals Man- government undertaking. Since then, min- agement Regulations 2002. Today, the mining sector has been playing vital role in na- ing sector has been identified as one of the tion development through inputs in the min- five jewels of economy due to its potential eral and construction industry. for economic growth and diversification. The Economic Development Policy (EDP) In Bhutan, the Geological Survey of India 2016 and Mineral Development Policy (GSI) commenced the geological investi- (MDP) 2017 provides policy direction for gation of mineral deposits in early 1960s. major reforms to maximize the benefit of Since then minerals such as gypsum, lime- mining sector to the nation and communi- stone, marble, coal, graphite, dolomite, iron ty. To implement the policy provisions, the stone, slate, quartzite, copper, tungsten, improved version (Mines and Minerals Bill granite, lead, zinc, etc. were explored and 2019) of the MMMA 1995 is submitted the mapped. As a result of GSI’s work and to ca- Parliament for enactment. ter the needs of infrastructure development, the government initiated the establishment of cement plant at Gomtu in early 1970s, with operation of first mechanized mine in the country at Pugli to supply limestone raw material.

1 Sangay Dendup, Mining Engineer, Department of Geology and Mines, MoEA, Thimphu, Bhutan Email: [email protected]

GEOSCIENCES AND MINING JOURNAL | 65 Current Mining Scenario

Figure 1: No. of mines and quarries based on the Region

The mining in Bhutan is limited to open sum Mine and Coal in southeast Bhutan cast mining. The most common mining were auctioned for a period of 15 years. method used is drilling and blasting, and These mines has been one of the top per- excavator-truck combination for loading formers in terms of payment of revenue to and transportation of minerals and waste. the government among the private sector Currently, there are total of 26 active mines firms. DGM is further exploring to re-auc- and 41 stone quarries in the country. The tion these mines and newly proven mineral regional distribution of the mines and stone reserves based on fulfillment of techno-eco- quarries is shown in Figure 1. Some of the nomic feasibility. minerals mined in Bhutan are gypsum, dolomite, quartzite, talc, limestone, marble, The governemnt also prioritize allocation of mines as captive to mineral based industry coal, iron stone, calc tufa, phyllite and con- to maximize the benefit to the nations. struction stones. The total area of the country occupied by mining activity is 4,027.24 acres, which constitutes about 0.04% of the Benefits from Mining Sector country’s area. Distribution of mines and quarries in each dzongkhag is shown is Ta- Revenue ble 1. Mining sector is the backbone of econom- The allocation of mines generally follows ic development. The economic growth of first-come, first-serve principle while gov- any nation is primarily driven by its rich- ernment also allocate mines through public ness in mineral resources and mining (e.g. auctions of those minerals deposits which Australia, Canada, Middle east countries, are explored and proven under public fund- Mongolia, South Africa, US, etc.). It not ing. only provides raw materials for industrial development, but it is also one of the main For e.g. three large scale mines viz. Chu- sources of foreign exchange through sale of naikhola Dolomite Mine, Khothakpa Gyp- minerals products.

66 | GEOSCIENCES AND MINING JOURNAL Table 1: Dzongkhag wise distribution of mines and quarries

Dzongkhag Type of minerals Construction stones Calc TufaCalc Clay Coal Dolomite Granite Gypsum Limestone Marble ore Iron Phyllite Quartzite Slate Talc Total No.

Bumthang 1 1 Chukha 3 6 1 10 Dagana 0 Gasa 0 Haa 0 Lhuentse 0 Mongar 2 2 Paro 5 5 P/gatshel 3 1 2 6 Punakha 0 S/Jongkhar 4 4 Samtse 1 3 1 5 4 14 Sarpang 0 T/gang 2 2 T/Yangtse 0 Thimphu 6 1 2 9 Trongsa 0 Tsirang 0 Wangdue 9 1 10 Zhemgang 0 Total 34 63

GEOSCIENCES AND MINING JOURNAL | 67 Mineral production for the last five year is contribution from coal mines operated by shown in Table 2. The quantity of the min- S.D. Eastern Bhutan Coal Nu. 1.302 billion, eral sale in domestic and export market in in addition to meeting Company Limited the year 2018 is as shown in Figure 2 and from 2004 to 2018 was Nu. 1.302 billion, Figure 3, respectively. Revenue from min- in addition to meeting fuel energy demands ing is generated in form of royalty, mineral from the domestic industries; creating jobs rent, land lease rent, auction fees (license), and business opportunities; shares and divi- Corporate Income Tax, Business dends; and supporting Corporate Social Re- sponsibility activities. The direct gross rev- Income Tax and other forms of taxes. It’s enue contribution from Khothakpa Gypsum contribution (both domestic and export) in Mine operated by Druk Satair Corporation 2018 is shown in Figure 4. In 2017-18, the Limited from 1994 to 2017 was Nu. 1.760 revenue contribution from royal of minerals billion, and additional of Nu. 25.518 million was Nu. 405.8 million. spent on CSR activities. Other benefits from this mine include shares and dividend, spur- Mining and mineral based industries have ring PoP industry development, and meet- been top Corporate Income Tax payers (Ta- ing requirements of cement industries in the ble 3). The benefits from the three large- country. Similarly, the direct gross revenue scale auctioned mines in Bhutan are sub- from dolomite mine at Chunaikhola oper- stantial. For instance, direct gross revenue ated by Jigme Mining Corporation Limited from 2005 to 2018 was Nu. 3.259 billion.

Table 2: Mineral production for the last five years Year Sl # Mineral in MT Total 2014 2015 2016 2017 2018 1 Calc Tufa 12,323.80 12323.8 2 Clay 10,208.95 10,208.95 3 Coal 121,890.58 85,164.45 117,783.00 161,526.74 186,823.75 673,188.52 4 Construction stones 1,474,394.94 2,203,065.41 3,414,215.00 3,828,254.00 3,730,975.36 14,650,904.71 5 Dolomite 2,040,690.96 2,662,309.68 2,367,659.00 2,536,693.31 2,821,166.44 12,428,519.39 6 Granite 4,362.21 3,889.05 26,364.04 6,293. 33 34,615.30 7 Gypsum 414,147.54 389,364.80 317,597.00 328,127.99 461,128.12 1,910,365.45 8 Irone ore 18,997.37 43,201.96 28,065.00 32,974.37 37,843.08 161,081.78 9 Lime stone 1,122,825.09 850,431.17 1,257,101.00 1,235,161.67 1,344,037.86 5,809,556.79 10 Marble 61,921.10 97,647.84 75,031.00 96,567.10 188,900.53 520,067.57 11 Phyllite 40,076.71 40,417.25 41,800.00 61,910.29 53,188.53 237,392.78 12 Quartzite 83,907.14 79,818.50 92,770.00 175,501.08 145,713.93 577,710.65 13 Slate 14 Talc 12,601.37 5,807.27 2,261.00 1,293.20 2,042.46 24,005.30 Total Production 37,049,940.99

68 | GEOSCIENCES AND MINING JOURNAL Figure 2: Sale of minerals in domestic in 2018

Figure 3: Export of minerals in 2018

Figure 4: Royalty and mineral rent collected by sales of mineral in 2018

GEOSCIENCES AND MINING JOURNAL | 69 Table 3: Top 20 CIT payer in FY 2016-17 (Source: National Revenue Report 2016-17). The mining companies and mineral based industries are in bold and italicized text. Note: Similar data not available for FY 2017-18 and FY 2018-19. CIT Payer Rank Druk Green Power Corporation Ltd. 1 Druk Holding and Investments 2 Bhutan Power Corporation Ltd. 3 Bank of Bhutan Ltd. 4 Bhutan Telecom Ltd. 5 Bhutan National Bank Ltd. 6 Royal Insurance Corporation of Bhutan Ltd. 7 Army Welfare Project Ltd. 8 Mangdechhu Hydroelectric Project Authority 9 Jigme Mining Corporation Ltd. 10 Penden Cement Authority Ltd. 11 SD Eastern Bhutan Coal Company Ltd. 12 Jigme Industry Pvt. Ltd. 13 Druk Satair Company Ltd. 14 State Trading Corporation of Bhutan Ltd. 15 Bhutan Ferro Silicon Pvt. Ltd. 16 Drukair Corporation Limited 17 Natural Resource Development Corporation Ltd. 18 Bhutan Polythene Company Ltd. 19 Bhutan Tourism Corporation Ltd. 20

Table 4: Royalty rates for minerals Minerals Domestic Rate (Unit based) Export Rate (Ad Valorem) Royalty Mineral Rent Royalty Mineral Rent (Nu/MT) (Nu/MT) (%) Dolomite 40 10 6.5 10% of Limestone 34 8.5 8.0 projected export royalty or the Marble 34 8.5 8.0 domestic royalty, Quartzite (undersize) 30 5 7.0 whichever is Talc 40 10 6.5 higher Gypsum 50 5 8.0 Coal 50 5 7.0 Construction Material 2.25 0.55 2.0 Phyllite 3.5 Any New Mineral 6.5

70 | GEOSCIENCES AND MINING JOURNAL Royalty from Minerals Broader Economic Impact

Until 2016, only unit-based royalty system Mining sector generates business oppor- was in practice. With the enactment of Re- tunities such as hiring of machineries and vised Taxes and Levies Act of Bhutan 2016, trucks, supply of good and services, and the country has adopted an Ad Valorem roy- opportunity for downstream industries. alty system for export of minerals. However, The GDP contribution from mining sec- the domestic royalty is levied on unit based tor for last five years is shown in Figure 6. system. Royalty of minerals for domestic The GDP from mining sector is exclusive market is incentivized to promote and sus- of GDP contribution from sectors such as tain in-country mineral based industry and mineral based industries and transportation infrastructure development. The rates of services which are directly dependent on royalty are shown in Table 4. mining activities. Further, the mineral and mineral based products have become the The royalty contribution to national exche- most important an export commodity. The quer from financial year 2013-14 to 2017-18 export data of 2018 shows that eight out of is shown in Figure 5. The increasing trend top ten commodity are mineral and mineral in the royalty contribution over the period is based products (Table 5). In 2018, the ex- mainly due to the introduction of Ad Valor- port of mineral and mineral based products em royalty system. constituted more than 53.15% of the total export by Bhutan to other countries. If the electricity is excluded from the trading, the export of mineral and mineral based products constituted about 71% (Table 6).

Figure 5: Royalty contribution to national exchequer from financial year 2013-14 to 2017-18

GEOSCIENCES AND MINING JOURNAL | 71 Table 5: Top ten export commodities Sl# Commodity Value in Million Nu. 1 Ferrosilicon 13,050.06 2 Boulders 2,121.64 3 Semi-finished products of iron or non-alloy steel 1419.67 4 Dolomite 1232.48 5 Portland Pozzilana Cement 1091.03 6 Cardamoms 929.41 7 Crushed stone 895.259 8 Carbides (of silicon) 842.56 9 Gypsum 718.81 10 Ordinary Portland Cement 616.28

Table 6: % of export of minerals and mineral based industries Year 2018 Export (in Million Nu.) 41,413 Mineral and mineral based industry (in Million Nu.) 22,011 % share 53.15% Trading excluding electricity Export (in Million Nu.) 30,835 Mineral and mineral based industry (in Million Nu.) 22,011 % share 71.38%

Mineral Based Industry In addition to economic development, mining sector also provides job opportunity to Wihout a mining none of mineral based in- the job seekers, addressing unemployment dustries, infrastructure and other develop- issues in the nation. Total jobs opportunities mental, but comes at cost of environment. created from the mining sector for the year 2018 is 1792 of which 1470 are men and Some of the mineral based industry in Bhu- 322 are women as shown in Figure 7. These tan are; Bhutan Carbide & Chemical Ltd. numbers are ones that are directly employed (BCCL), Bhutan Ferro Alloys Ltd. (BFAL), in mining. There are other employment in- Druk Ferro Alloys Ltd. (DFAL), Druk volved in transport of minerals from source Wang Alloys Ltd. (DWAL), Jigme Min- to market. ing Corporation Ltd. (JMCL), Penden Ce- In the next few years, the sector is expect- ment Authority Ltd. (PCAL), Druk Plasters ed to create more job opportunities with the and Chemical Ltd. However, lifting of moratorium. a properly planned, efficiently regulated Since, minerals are non-renewable natural and professionally managed mining indus- resources, it’s collective responsibility of all try can minimize such impacts and make a the citizens to ensure that these resources are significant contribution to national Employ- ment Opportunities. 72 | GEOSCIENCES AND MINING JOURNAL Figure 6: GDP contribution from mining sector

Figure 7: No. of employment figures in mining sector utilized in a sustainable manner to diversify National Statistics Bureau. (2018). Statistical the economy as it forms an integral part of Yearbook of Bhutan. the supply and value chain these industries. Norbu, D. (2013). Mining has great economic potential for Bhutan. Retrieved from https:// thebhutanese.bt/mining-has-great-econom- Reference ic-potential-for-bhutan/ Tshering, T. (2019). State of the Nation. Centre for Bhutan Studies. (2007). Chakzampa Royal Government of Bhutan. (2016). Economic Thangtong Gyalpo: Architect, Philosophier Development Policy. and Iron Chain Bridge Builder. Royal Government of Bhutan. (2017). Mineral Ministry of Finance. (2016-2017). National Rev- Development Policy. enue Report. Royal Government of Bhutan. (1995). Mines National Statistics Bureau. (2018-2019). Eco- and Minerals Management Act. nomic Census of Bhutan. Royal Government of Bhutan. (2002). Mines Ministry of Finance. (2016-2017). Revised Tax- and Mineral Management Regulations es and Levies Act of Bhutan.

GEOSCIENCES AND MINING JOURNAL | 73 ABOUT THE CHEMICAL LABORATORY Ugyen Dorji1 , Radha Devi Sharma2

Introduction Laboratory Facilities (Instruments) The Chemical Laboratory is a support service section under the Geological Survey Analytical instruments available with the Division of the Department. It is comprised chemical laboratory are; of the following sub-units; • Atomic Absorption Spectrophotometer • Sample Processing Unit (Crushing, Pul- (AAS) (Figure 1) for estimation of trace verizing, Sieving and Re-packaging of metals in minerals, sediments and water samples) samples; • Wet Chemical Laboratory (Gravimetric • Flame Photometer (Figure 2) for estima- and Titrimetric Analysis) tion of alkali and alkaline earth metals; • Instrumental Analysis Laboratory (Spec- trometric analysis - using AAS and Microwave Digestion Unit (Figure 3) for Flame Photometer) digestion of samples.

Roles Analytical Services The Chemical Laboratory is responsible for generating analytical data of rock & mineral • Sample Preparation of all Geological samples employing gravimetric, volumetric Materials- Crushing & Grinding, Pulver- and spectrometric methods, primarily to as- izing, Mixing, Sieving and Re-packag- sist the Department in the following activi- ing; ties; • Determination of Major Oxide compo- sition of geological materials (silicates, • Geological Mapping; carbonates, sulphides, oxides, rocks and • Mineral Prospecting & Exploration; ores) by acid digestion; • Determination of Moisture Content and Monitoring of active mines through period- Loss on Ignition (LOI) of geological ma- ic sampling of industrial minerals. terials; • Determination of Base Metals in samples (Copper, Lead, Zinc, Manganese and Nickel) using AAS;

1 Ugyen Dorji, Chief Chemist, Department of Geology and Mines, MoEA, Thimphu, Bhutan Master in Environmental Science, University of Wollongong, Australia, Email: [email protected] 2 Radha Devi Sharma, Assistant Chemist, Department of Geology and Mines, MoEA, Thimphu, Bhutan BSc. Mathematic & Chemistry, Sherubtse College, RUB. Email: [email protected]

74 | GEOSCIENCES AND MINING JOURNAL Figure 1: Atomic Absorption Spectrometer Figure 2: Flame Photometer

• Water quality analysis for the following parameters: pH, Calcium (Ca), Magne-

sium (Mg), Sulphate (SO4), Chloride (Cl), Sodium (Na), Potassium (K), Total Hardness, Total Alkalinity, Total Solids (TS), Total Suspended Solids (TSS) & Total Dissolved Solids (TDS).

General Information

Sample Type Figure 3: Microwave Digestion Unit

Metallic and Non-metallic (industrial min- Sample Weight & Volume required for erals) samples routinely analysed in the analysis chemical laboratory are limestone, dolomite, quartzite, gypsum, quartz, talc, coal, • Rock and mineral sample: 3-5 kg/ sam- pyrite and iron-ore. ple; • Water sample: minimum of two liters/ Lab Test Charges sample. (*container must be properly washed and rinsed with sample water). Mineral and Rock samples originating from the department field activities are analyzed Sample Packaging free of cost, while the private samples are charged a minimal rate. All samples must be submitted with clear sample identification along with sample • Nu. 1000/- per sample for rock and min- number written on sample bags. A proper eral sample; list of samples must be provided on submis- • Nu. 800/- per sample for water sample. sion of samples. Samples must be submitted in airtight plastic bags and sealed plastic containers (in the case of water sample).

GEOSCIENCES AND MINING JOURNAL | 75 Improper labeling or without sample sub- (1) Note: The TADA of drilling Staffs and mission form attached will not be processed other expenses for HSD, engine oil, until correct sample information are provid- gear oil, hydraulic oil etc. are not in- ed. cluded in meterage charge.

Sample Storage 10% service charge will be applica- ble on the total estimation. On completion of analysis, powdered samples will be stored with the laboratory for a period of 100 days after which it will be dis- GEOTECHNICAL carded. Water samples will be immediately LABORATORY SERVICES disposed upon completion of the analysis. The Department of Geology and Mines Turnaround Time (TAT) have a Geo-tech lab under the Engineering Geology section which provides its services All laboratory analysis are done on “First not only to the department but to other gov- Come First Serve” basis. ernment agencies as well as to the private and public sectors. Given below is a list of Sample test reports will usually be available services/tests provided by the geo-tech lab. within one week from the receipt of samples, provided there are no sample backlogs, national holidays and technical issues such as power cuts, equipment breakdown and water problem.

Incomplete submission of documents will also result in slow turnaround time.

Reference

Guyana Geology & Mines, Retreived from https://www.ggmc.gov.gy/services/all/ chemical-laboratory

DRILLING SERVICES

Service Purpose Depth of Borehole Rate per Who can avail (meter) meter (Nu.) the service? Diamond § Mineral Exploration 0-50 3500 § Government Drilling § Engineering geological 51-100 5000 agencies or geotechnical study >101 6400 § Corpora- (foundation study, slope tions stability, site suitability § Companies etc.) § Private firm § Groundwater exploration or individual

76 | GEOSCIENCES AND MINING JOURNAL Sl # Name of Purpose Methods/ Equip- Rate (Nu.) Quan- Remarks Tests ment tity of sample required Tests for Soil Samples: 1. Standard To determine the The test proce- 7,500.00 Test carried out with Penetration relative density dure is described per pit/ per drilling on-site, only Test (SPT) and the bearing in ISO 22476- borehole disturbed samples capacity of soil. 3, ASTM D1586 NA retrieved which cannot and Australian Stan- be used for tests. dards AS 1289.6.3.1. 2. Portable To determine the Portable Penetrom- 5,000.00 per NA Test carried out along Penetration bearing capacity eter. pit with or without pitting Test (PPT) of soil. at the site. Can pene- trate ground up to 2m. 3. Particle size Particle size Sieve analysis (Dry Sieve analysis- Sieve Sieve analysis done for distribution analysis for soil and Wet) for coarse 975.00 per Analy- coarse grained soil and test or Sieve classification grained particle size sample sis: 2-3 hydrometer is done for Analysis down to fine sand. kg finer grained soil- to Hydrometer differentiate between Hydrometer test is test- 975.00 Hy- different types of silt carried out for fine per sample. drome- and clay. grained soil like silt ter test: and clay. 2 kg. 4. Atterberg Classification of Liquid limit using 975.00 per 2 kg A major component in Limits (Index fine-grained cohe- Casagrande cup. sample classification of fine- of Plasticity) sive soil as well as grained, cohesive soil. Tests determination of Also determines the other engineering liquid limit, plastic lim- properties of soil. it, index of plasticity. 5. Bulk Density To determine the Linear measurement 825.00 per 2 kg Samples usually and Dry bulk density and method, Immersion sample collected using a bulk density test dry density of the in water method and density tube. soil. water displacement method. 6. Water content To determine water Oven dry method. 225.00 per 1 kg Samples must be prop- Test content of soil sample erly sealed and packed sample as it was so that the water con- sampled in the tent of the sample does field/in-situ. not change (1% change acceptable) from the in-situ conditions. 7. Specific To determine the With Hydrometer 975.00 per 1 kg Gravity Test specific gravity of and Pygnometer. sample the specimen. Tests for Rock Samples: 8. Aggregate To determine An aggregate impact 1,500.00 per 10 kg Carried out during road Impact Value the Aggregate apparatus. test construction, founda- (AIV) Test Impact Value (a tion study, etc. relative measure of resistance of the aggregates to sudden impact)

GEOSCIENCES AND MINING JOURNAL | 77 9. Point Load To determine the Point Load Test 600.00 per test 5 Quick and easy test. It Test rock strength index Machine. pieces is simple and conve- of a specimen. of rock nient. (which can then be sam- used to calculate/ ples estimate the Uni- axial Compressive Strength) 10. Porosity Test To measure the ASTM Standard Test 675.00 per test 10 Useful in understand- porosity of rock method C97-83: Us- Pieces ing characteristics of specimens. ing Vaccum machine, of rock the rocks mineral for desiccator, oven and sam- hydrogeological or Weighing machine. ples groundwater or geotechnical studies, and oil and gas exploration etc 11. Schmidt To determine the Using a Schmidt 800.00 per test Per Usually an on site test Hammer Re- intact strength Hammer spot/ but can also be carried bound Test of the rock and 22 out at the lab. (with the compressive read- introduction of some strength of the rock ings. correction factors laid (surface hardness out in the standards) and penetration resistance).

78 | GEOSCIENCES AND MINING JOURNAL Royal Government of Bhutan Department of Geology and Mines www.moea.gov.bt P.O. Box 173

GEOSCIENCES AND MINING JOURNAL | 79