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Mining impact on Environment Dr. Manoranjan Hota 07 September, 2016 [email protected] What is an impact? • EIA Notification: …….potential environmental impacts….. • The impact of an activity is a deviation (a change) from the baseline situation that is caused by the activity. • To measure an impact, you must know what the baseline situation is. • The baseline situation is the existing environmental situation or condition in the absence of the activity. • The baseline situation is a key concept in EIA. The baseline situation • In characterizing the baseline situation, many environmental components may be of interest. • The components of interest are those that are likely to be affected by your activity—or upon which your activity depends for its success Water: Quantity, quality, reliability, accessibility Soils: Erosion, crop productivity, fallow periods, salinity, nutrient concentrations Fauna: Populations, habitat Env Health: Disease vectors, pathogens Flora: Composition and density of natural vegetation, productivity, key species Special Key species: ecosystems Types of impacts & their attributes EIA process is concerned with all types of impacts which can described in many ways Intensity Direction Spatial extent Duration Frequency Reversibility Probability • Direct & indirect impacts • Short-term & long-term impacts • Adverse & beneficial impacts • Cumulative impacts But all impacts are NOT treated equally. The Preliminary Assessment • The purpose of a preliminary assessment is to provide documentation and analysis that: • Allows the prepare to determine whether or not significant adverse impacts are likely • Allows the reviewer to agree or disagree with the preparer’s determinations • Sets out mitigation and monitoring for adverse impacts Why EIA ??? • Protect environment and control pollution • Environment Protection Act ,1986 • Environment Protection Rules, 1986 , • Section 5 Environment Protection Rules 1986: Prohibitions and restrictions on the location of industries; carrying on of processes and operations in different areas • EIA 1994 • EIA 2006 is supersession of EIA 1994, except in respect of things done or omitted to be done before such supersession • Coal is an essential resource and plays a major role in producing electricity across the globe. • Coal is estimated at > 861 billion ton globally. • India has the fifth largest coal reserves in the world. • While India accounts for about 286 billion tonnes of coal resources, other countries USA, China, Australia, Indonesia, South Africa and Mozambique also share major share of coal resource. • Coal meets approximately30.3% of the global primary energy needs and generates 42% of the world’s electricity. • Of the total reserves, nearly 88% are oncoking coal reserves, while tertiary coals reserves account for a meagre 0.5 % and the balance is coking coal. • The short-term increase in coal production may negatively impact the long-term growth due to finite nature of the coal resource and depletion impact on environment. • Therefore, there is a need to adopt and practice sustainable mining. • The power generation from various sources indicates that coal is the major source are: – (i) Thermal power: 68.19% (Coal: 58%; Gas: 8.9%; Oil: 0.52%); – (ii) Hydro Power: 18%; – (iii) Nuclear power: 2 %; – (iv) Wind power: 12.32% Coal Reserve & Exploration Needs • Current inventory of Indian coal reserves strong at 248 Bt., including only 93 Bt in Proved category, • The total potential coal-bearing area of the country is about 22,400 sq.km.; out of which 10,200 sq.km. (45%) has been covered by regional exploration as on 1.1.2002. Exploration Needs • As of now 10,200 sq. km. coal bearing areas have been regionally explored by GSI and others. Another 12,200 sq. km. is yet to be regionally explored. • There is urgent need to accelerate the pace of exploration. India is maintaining balance between its resource base and share in production contribution. Currently India's per capita proved coal reserve is 79 tonnes as compared to world average of 154 tonnes. • Out of this inventory, about 50% area covered by Detailed Exploration. • Out of the total Inventory of 248 Bt, 71 Bt are in proved category within 300m depth. • The rest 81.5 Bt are in Indicated and Inferred categories. • Additionally 56.7 Bt resources are available in Indicated and Inferred categories (excluding Jharia CF) within 300-600m depth. Quality of Indian Coal • Indian coal has high ash content. The average ash content in Indian coal is 35-38 per cent while imported coal ash content 10-15%. • Indian coal is characterized by: – – – – Lower to medium grade coal; high ash content; low moisture content; and low Sulphur content. Mining technology • Avenues of harnessing alternatives such as CBM and in-situ gasification of coal from the inaccessible deposits also need to be explored. • India has been practicing mining by opencast mining (87%) and underground mining (23%). Plausible Challenges • Coal resource getting more and more limited. • Focus of mining requires moving – to higher depths, – larger systems and – processes to be adopted which are more efficient than traditional truck and haul. The other plausible challenges – shifting of mining from one mine to other – – – – by abandoning excavated coal mines without proper reclamation; improper implementation of mine closure plans ; practice of horizontal mining thereby destroying forest and wild life; possibility of extending vertical mining beyond 300 meter depth; availability of advanced technology; change in mind set; etc. Mining activities • Unregulated mining has potential to harm air, water and soil. • Choice of actual mining method depends on various factors, viz. – Deposit characteristics, – Percentage recovery, production, scheduling scope of mechanization and automation, workforce requirements, – Concerns over land and water resource use, health and safety requirement – Environmental concerns including pollutant emissions, waste generation, public health and safety concerns, – Land reclamation, – Operating and capital cost estimates etc. • Adequate environmental and safety safeguards required to be established as mines are with varying levels of environmental protection. Environmental Damages: i. Open Cast Mining Distinct from other forms of mining, due to that fact that it does not require extractive methods that include tunneling into the earth. Occurs at the soil surface. • • • • • • • • • • Destruction of the topographical landscape Degradation of ecological communities Degradation of water quality Destruction of agricultural and forest lands Noise pollution Air quality Sedimentation and erosion Land subsidence Vibration from blasting and air blasts Old mines often converted into landfills Underground Mining • Underground mining has the potential for tunnel collapses and land subsidence . • It involves large-scale movements of waste rock and vegetation, similar to open pit mining. • As water takes on harmful concentrations of minerals and heavy metals, it becomes a contaminant. This contaminated water can pollute the region surrounding the mine and beyond. • Most underground mining operations increase sedimentation in nearby rivers through their use of hydraulic pumps and suction dredges; • Blasting with hydraulic pumps removes ecologically valuable topsoil containing seed banks, making it difficult for vegetation to recover. • Deforestation due to mining leads to the disintegration of biomes and contributes to the effects of erosion. • Topography of the mining area should be analyzed so as to address the terrain viz. hill slopes, coastal and inland topography. • The water reservoirs, water flow pattern of water bodies, Perennial streams, if any should be identified and special attention be attributed. • Geology of the area is very important to ascertain seismic sensitivity. Dust • Dust can release a variety of heavy metals commonly associated with health problems. Can be absorbed into lung tissue, causing problems like pneumoconiosis and silicosis. Carbon output • Mining, like most heavy industries, is dependent on fossil fuels, which generate the energy needed to operate a mine. Environmental standards need to be implemented. Species habitat • Mining is an inherently invasive process that can cause damage to a landscape in an area much larger than the mining site itself. The effects of this damage can continue years after a mine has shut down, including the addition to greenhouse gasses, death of flora and fauna, and erosion of land and habitat. Mine Subsidence: • Surface subsidence can cause extensive damage/degradation affects. • A thorough understanding of subsistence patterns of underground mining on the surface to be quantified. • This ensures the safe, maximum recovery of a coal resource, while providing protection to other land uses. Water Pollution • Mine operations work to improve their water management, aiming to reduce demand through efficiency, technology and the use of lower quality and recycled water. • Water pollution is controlled by carefully separating the water runoff from undisturbed areas from water which contains sediments or salt from mine workings. • Clean runoff can be discharged into surrounding water courses, while other water is treated and can be reused such as for dust suppression and in coal preparation plants. Acid mine drainage • Acid mine drainage (AMD) is metalrich water formed from the chemical reaction between water and rocks containing sulphur-bearing minerals can be a challenge at coal mining operations. • AMD can be treated actively or passively. Methane (CH4) • Methane (CH4) is a gas formed as part of the process of coal formation and released from the coal seam and the surrounding disturbed strata during mining operations. • Methane is a potent greenhouse gas, with a global warming potential 23 times that of carbon dioxide. • While coal is not the only source of methane emissions – agricultural activities are major emitters – methane from coal seams can be utilised rather than released to the atmosphere with a significant environmental benefit. Wildlife • The baseline status of wildlife in the mining area is one of the most important components. • To be ideal wildlife habitations following data on fauna should be collected. – – – – – – – Distribution Abundance Rarity Species diversity and critical habitat requirements Migratory and travel routes Predator – prey balance Habitat residence Public Utilities • Vehicular traffic during mine development and operation may result in excessive use of existing public infrastructure like roads, railways, waterways etc. and may cause congestion and pollution. • An existing road, passing through habitation, may cause air pollution problem due to increase in traffic volume. Similarly public utilities such as water supply, drainage, power grid may also be utilized. • Baseline information / data on existing public utility infrastructure and service should be reported. Site Specific Features • Any site-specific features such as nearness to large water body, nearness to forest etc. • Specific Study Required for nearness to water body/reservoir Details of hydrogeology and hydrology Nearness to forest. • Detailed conservation plan w.r.t nearness to township blasting vibration study groundwater scarcity area. • Details of ground water availability and recharge of ground water Environmentally friendly mining • New mining technologies and regulations would significantly improve mining efficiency and reduce environmental impact. • Closing down illegal mines • Choosing advanced mining technology Improving Efficiencies • Fluidised Bed Combustion • Supercritical & Ultra-supercritical Boilers • Integrated Gasification Combined Cycle Coal Mining and Environmental Impact Event Change in land use, land –cover and land form Consequences Disturbance in natural water-sheds & drainage pattern of the region Disturbance in wind direction, flow and temperature Ultimately disturbance in rivers/stream flow, agriculture patterns etc. Floods and loss of bio-diversity Release of greenhouse gases like carbon di-oxide and methane due to fracturing of strata and in-situ combustion of coal seams. Global warming consequences. Waste products including uranium, thorium and other radioactive and heavy metal contaminations Air/water/soil/food grain contamination or direct exposure to flora/fauna and other related Event Change in land use, land – cover and land form Consequences Disturbance in natural water-sheds & drainage pattern of the region Disturbance in wind direction, flow and temperature Ultimately disturbance in rivers/stream flow, agriculture patterns etc. Floods and loss of bio-diversity Release of greenhouse gases like carbon di-oxide and methane due to fracturing of strata and insitu combustion of coal seams. Global warming consequences. Waste products including uranium, thorium and other radioactive and heavy metal contaminations Air/water/soil/food grain contamination or direct exposure to flora/fauna and 32 other related Event Acid rain Acid mine drainage Disturbing recharge area Disturbances in the drainage and water-sheds of surface water bodies Dust nuisance due to blasting, drilling and digging Subsidence above tunnels Rendering land unfit for the other use Sizing of coal Consequences Contamination of surface/ground water, soil, agriculture Contamination in surface/ground water, soil and agriculture Interference with groundwater and water table level, surface water Causing change in flows discharges of rivers and streams and Air pollution health impact and visibility hindrance. Damage to building and structure. Sometimes damaging the infrastructure. • Wastage of non-renewable resources Air pollution health impact and visibility hindrance. 33 Event Consequences Transportation /loading/unloading Air pollution health impact and visibility hindrance. Beneficiation of coal Contamination of surface/ground water, soil, agriculture Air pollution health impact and visibility hindrance. 34 Objectives of sampling Environmental sample Objective Parameters to be analyzed Ground water quality To study the impacts due to leaching of acidic & metal contaminated water generated from tailing and waste rock. pH, Sulphate, Acidity, Alkalinity, TDS, TSS, Elemental metals, COD, Chloride, Fluoride, Conductance Surface water quality pH, Sulphate, Acidity, To study the impact due to Alkalinity, TDS, TSS, leaching of acetic & metal Elemental metals, contaminated water COD, Chloride, generated from tailing and Fluoride, waste rocks Conductance, COD and BOD Mitigation Measures • Top soil be stacked properly with proper slope & grassing. • External overburden dump be not more than prescribed height and OB should be stacked at earmarked dump sites only. Monitoring and management of rehabilitated area should continue until the vegetation becomes self sustaining. • Catch drains, siltation ponds, Garland drains and settling pond. • Development of green belt for suppression of dust around the mine • Quarterly monitoring of Data water level and quality and submission of data to concerned department • Providing recharge measures for meeting water requirement. • Providing rain water harvesting system. • Provision of high efficiency dust suppression system in coal handling plant • Treatment plant for sewage, workshop and CHP wastewater 36 Mitigation measures • Monitoring of vehicular emission and construction of metal top road • Establishment of ambient air quality station for RPM,SO2,NOX and CO and submission of data to concerned departments • Adequate measure for control of noise levels below 85dB(A) • Treatment of industrial waste water to confirm the prescribed standard • Treatment and disposal of acidic mine water as per prescribed standards • Establishment of Environmental laboratory and environmental management cell. 37 • Provision of Environmental cell with ecologist & social scientist • All internal roads be black topped and good house keeping • Coal transport in duly covered conveying system/vehicles to present fugitive emission during transportation • Development of green belt around the area. 38 Sustainable mining vis-à-vis environmental protection: • Self-regulation should be put in practice • Board of the Company should own responsibility for any non-compliance. • Need to amalgamate smaller mines into bigger units with fewer openings. • Small scale mining should be avoided so that improved heavy machinery can be put to use for enhance coal production so also pollution and other environmental issues are kept to minimum. E.g., use of In-Pit Crushing and Conveyor (IPCC) which will reduce no of small dumpers, its transportation, emission of pollutants etc. • Coal mining in India has been carried out to an average 100 meters depth except in Jharia Coal field where the mining is beyond this depth. • Keeping in view the pristine forest and principles of sustainable development in view, it would be prudent go for mining vertically down (may be upto 800 meters) rather than horizontally. • Vertical mining shall delay in forest diversion and will help in climate change mitigation. • Cluster approach for mining so as to minimize small scale mining. • Cumulative Impact Assessment for cluster be carried out for environmental management and mitigation. • Sequential mining need to be put in practice so that coal from a coal field is exhausted completely and the Over Burden (OB) and voids are rehandled completely and the land is returned back to its near original status for agriculture purposes. • Large numbers of voids which are created due to mining are left out without following any scientifically mine closure plan. The mine voids should be used recharging of ground water and also for supply of treated water to villagers. • Adequate green belts should be provided for air pollution control. • Rain water harvesting and water conservation should be a part of the environmental management of the project. • Transformation from conventional coal transportation by road to conveyor belt and rail transportation. • Washeries need to be installed at the pit head so as to prevent long transportation and disposal of rejects. Role of MoEFCC • In order to ensure integration of environmental, forestry and wildlife concerns into developmental project, the Ministry examines/appraises projects essentially under the framework of – Environment (Protection) Act, 1986; – Forest(Conservation) Act, 1980 and – Wildlife(Protection) Act, 1972. • EIA Notification, 2006 issued under Section 3, subsection(2), clause (v) of the Environment(Protection) Act, 1986 read with clause (d) of sub-rule(3) of rule 5 of Environment (protection) Rules, 1986. • EC is required for any developmental projects under EIA Notification, 2006. • To formulate a transparent, decentralized and efficient regulatory mechanism to: Incorporate necessary environmental safeguards at planning stage Involve stakeholders in the public consultation process Identify developmental projects based on impact potential instead of the investment criteria Transparency Certainty EIA Costeffectiveness Participation Credibility Accountability Practicability Flexibility EIA Benefits/Flipsides Benefits Flip sides Provides systematic methods of Impact assessment Time -consuming Estimates the cost/benefits trade-off of alternative actions Costly Facilitates the Public participation Title public participation in actual implementation Provides an effective mechanism for Coordination Environmental integration Negotiations Feed back Unavailability for reliable data (mostly in developing countries Top-level decision making focused on scientific analysis Triggers an institutional building Presentation of EIA report(bulky volumes, scientific explanation, sometimes difficult to understand) Achieve a balance between the impact of Developmental and environmental concern Compliance monitoring after EIA is seldom carried out Compliance to EC Conditions Judicial process and NGO activism Thank You