Impact Assessment and Project Appraisal, volume 22, number 3, September 2004, pages 235–250, Beech Tree Publishing, 10 Watford Close, Guildford, Surrey GU1 2EP, UK
Opencast mining impact A methodology for cumulative impact assessment of opencast mining projects with special reference to air quality assessment Pratik Dutta, Sandip Mahatha and Parijat De
It has been recognized worldwide that consideration of cumulative impacts should be an integral part of the environmental impact assessment process and that sector-specific methodologies should be evolved to address these impacts. A generic methodology for cumulative impact assessment of opencast mining projects has been developed with special reference to air quality assessment. It involved questionnaire checklists and a geographical information system for scoping of the impact assessment study, and the ISCST3 air quality dispersion model for the analysis of impacts. Its use was illustrated by a case study at an opencast iron ore mine. The methodology could identify a number of potentially significant cumulative impacts. Also, the analysis of air quality impact suggested that in some areas surrounding the mine the cumulative pollutant levels could be significantly high even if the effects of project-related impact were low. Keywords:
cumulative impact assessment; opencast mining; air quality; India
S
INCE ITS INTRODUCTION more than 30 years ago, environmental impact assessment (EIA) has gradually developed into a powerful planning and decision-making tool. EIA studies the environmental consequences of a proposed project so that corrective actions can be taken to ameliorate the adverse impacts. Historically, the thrust of EIA has been on the prediction of changes in the natural and socio-economic environment of single development activities. However, concerns have often been focused on the combined effects of multiple activities: it became increasingly clear that the conventional approaches to single project assessment would not necessarily address the broad environmental degradation over many years; namely, the result of cumulative effects or cumulative impacts. As the stress on the environmental resources continue to increase as a result of excessive development pressures, cumulative impact considerations become even more important in the EIA process. It has been felt, therefore, that, without incorporating cumulative effects into environmental planning and management, it would be impossible to move towards sustainable development (CEQ, 1997). The United States Council on Environmental Quality (CEQ) has defined cumulative effects as (CEQ, 1978):
Pratik Dutta (corresponding author) is Faculty Member and Sandip Mahatha Project Fellow, Department of Mining and Geology, Bengal Engineering College (Deemed University), Howrah-711103, India; E-mail:
[email protected];
[email protected]. Parijat De is Principal, Government Engineering College, Kalyani-741235, India.
“the impact on the environment which results from the incremental impact of the action when added to other past, present and reasonably foreseeable future actions, regardless of what agency or person undertakes such other actions.”
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1461-5517/04/030235-16 US$08.00 IAIA 2004
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Cumulative impacts can result from individually minor but collectively significant actions taking place over a period of time. These are not new types of impact but recognition that impacts from individual projects and activities can combine together in time and space. Hence, to address cumulative impacts in an EIA, it is necessary to perform the key tasks within the EIA framework by broadening the spatial and temporal extent of the study (CEAA, 1999). This broadened scope of the EIA is termed cumulative effect assessment (CEA) or cumulative impact assessment (CIA). Cumulative impact considerations have been required in the EIA process for a long time. For example, CEQ regulations incorporated this requirement back in 1979. This was followed by other countries such as Canada, Australia, UK, Belgium, Germany, Greece, Ireland, Netherlands, Portugal, Spain, Hong Kong, where cumulative impact considerations have been made an integral part of the EIA legislation. However, incorporation of these considerations has been minimal in practice because of confusion over appropriate spatial and temporal boundaries in impact studies, lack of emphasis by the project proponents and the government agencies, and more importantly, the absence of structured methodologies (Canter and Kamath, 1995). In recent years, though, studies have increasingly started to address this issue and have shown that the existing EIA methodologies and assessment tools can often be combined effectively to address cumulative impacts (CEQ, 1997; CEAA, 1999; ECDGXI, 1999). Nevertheless, the concepts and guidelines developed thus far are somewhat generic in nature and it is important to develop sector-specific methodologies. The main objective of this paper is to present a methodology for CIA of opencast mining projects. The manner in which some of the critical activities within the EIA process could be carried out to address the cumulative impacts is discussed. Opencast mining projects can have significant impacts on a variety of environmental resources. Amongst these, air quality of the surroundings resulting from particulate emission from the mines is a key impact that needs to be studied in the EIA. Therefore, specific focus has been put on the methodology for assessing impacts on air quality. It has been argued that techniques such as questionnaire checklists, geographical information system (GIS), and impact models can be combined effectively to carry out the critical activities within the EIA process. The methodology presented here is illustrated by a case study of an opencast iron ore mine in India, for which the CIA was carried out using checklists specifically developed for the purpose, GIS and an air quality dispersion model. The results demonstrate the effectiveness of the methodology in systematically identifying and analyzing the cumulative air quality impacts that may result from the project in combination with other projects. 236
Methodology for CIA The exact components, staging and the responsibilities for carrying out the EIA process depend, to a great extent, on the regulatory requirements of the country. However, most EIA processes have a somewhat similar structure, which is an aggregate of a few activities to be implemented at various stages of the process: screening; scoping; analysis of impacts; identification of mitigation measures; evaluation of the significance of impacts; reporting; decision-making; monitoring; and follow-up. Of these, the central activities, comprising screening, scoping, analysis of impacts, identification of mitigation measures, evaluation of the significance of impacts and reporting, are normally carried out by the project proponents. The rest, although essential to EIA, are usually the responsibility of the environmental agencies. Screening to decide whether a detail EIA is required or not is normally spelt out clearly by the environmental agencies depending on the size and complexity of the proposal. For instance, in India, EIA for mining projects is required when the lease area exceeds five hectares. Once adverse impacts are predicted, identification of mitigation measures depends, to a large extent, on the cost and availability of best practicable management systems. To decide whether the residual impacts, after implementation of the mitigation measures, are significant and unacceptable is often a contentious issue and the decision often occupies a fluid boundary between science and politics (Sadler, 1996). The job of the assessor is, therefore, limited to providing the information on the results of the assessment with regard to nature, magnitude, timing, and duration, as well as the attribution of importance or value to the findings. This, however, underlines the importance of the impact analysis activity of the EIA process. Scoping is the foundation for an effective EIA that sets up an efficient process by identifying the right questions for which answers are needed for decision-making (Sadler, 1996). If scoping is not carried out properly, the EIA may become voluminous and may address irrelevant or less significant issues in detail while overlooking the more significant ones (Everitt, 1995). Therefore, the two activities of scoping and analysis of impacts are most critical to a sound and cost-effective CIA. Mahatha and Dutta (2003) have explained how different activities should be performed to address cumulative impacts within the basic EIA framework. The key tasks within these activities are given in Figure 1. It is clear from the figure that an essential difference between the project-specific EIA and CIA is the consideration of larger geographical and temporal boundaries to include other past, present and reasonably future actions during both the scoping and analysis phases of the process. Therefore, any methodology for CIA should essentially demonstrate how the other actions could be considered during these two phases.
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An essential difference between the project-specific EIA and CIA is the consideration of larger geographical and temporal boundaries to include other past, present and reasonably future actions during the scoping and analysis phases
Scoping Scoping involves the identification of key issues of concern the project-specific EIA and CIA and the affected resources, thereby ensuring that the assessment remains focused and the analysis manageable and practicable. The larger regional nature and the complexity in assessment mean that scoping must be strictly applied to avoid assessing more than is necessary. The first step in scoping is to identify the direct impacts of the project under study on the important environmental resources. For identification of these direct project-related impacts it is important to prepare systematically a list of activities that may result from the construction, operation and closure phases of the project.
The next job is to identify the environmental impacts of these activities and the resources affected by them. Identifying other past, present and future actions that have caused, or may cause, impacts and may interact with those caused by the project under review is critical to establishing the appropriate geographic and time boundaries for the CIA. Only those environmental effects of other projects or activities that may combine with the environmental effects of the project in question should be included in the assessment. Spatial boundaries cannot be the same for all the environmental resources and can be delineated by the consideration of project impact zones. The procedure for determining the project impact zone for air quality is explained in the next section. Air quality impact zones can be generated separately for different projects and mapped in GIS. When any overlap between the impact zones of the project under study and that of the other projects occurs, it is concluded that the area under the overlap zones could be subjected to cumulative impacts. How far back in time the information needs to be considered will depend on the historical use of the area and the availability of the information. However, effects of many past activities can be made available through the examination of baseline conditions. In setting the future time boundary, five years is a reasonable time since beyond that there will be too much uncertainty associated with the development proposals (CEAA, 1999). For future
Identify significant issues of concern associated with the proposed project Scoping
Identity spatial boundaries for the analysis Identify temporal boundaries for the analysis Identity other actions that may contribute to cumulative impacts
Analysis of impacts
Define a baseline condition for the important regional resources
Assess the impacts of all actions on the resources
Identification of mitigation measures
Evaluation of significance of impacts
Follow-up
Recommend mitigation measured
Evaluate the significance of impacts after analysis
Monitor the cumulative impacts through regional monitoring
Figure 1. Tasks within the EIA framework to address cumulative impacts
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actions, projects that have been approved or are in the process of being approved should be included. If certain actions do not require any formal approval but are relevant to the assessment, they should also be included, especially if there is a high level of certainty that such actions will take place. Likewise, actions that may be induced by the project in question should also be considered. When there is insufficient information on future projects and activities, best professional judgment should be applied. A number of impacts may be identified that are likely to affect cumulatively the important environmental resources, but it is necessary to limit the study only to those impacts that may be significant. During scoping, the activity–environment relationships are only poorly understood, factual information is limited, and/or there is a high degree of uncertainty regarding the potential impacts. A qualitative approach, drawing on previous understanding of the project characteristics and impacts, can establish a rational basis for determination of impact significance (Hilden, 1996). Table 1 can be used for drawing up the different columns of the checklist useful for identification of the project actions for an opencast mining project during various stages of implementation of the project. The list of actions given in Table 1 is more or less exhaustive and covers all possible actions of such a project. depending on the local circumstances additional actions may be added. For identification of project–environment interactions any primary impact Table 1. Checklist of project components for an opencast mine -
Land acquisition and creation of new land use Removal of vegetation Demolition of important structures Impoundment, culverting, realignment, or other changes to the hydrology of the water courses Closure, diversion, or modification of exiting transport route or creation of new transport route Closure, diversion, or modifications of exiting utilities like power line, pipeline etc. or creation of new utilities Ground water removal Civil construction work Provision of civic amenities like housing, school, medical facilities, water etc. Provision of direct and indirect employment opportunities Surface run off Top soil and sub soil removal and storage Overburden removal and loading at pit Ore removal and loading at pit Disposal of solid waste Disposal of liquid effluents Overburden transportation from pit Ore transportation from pit Overburden dumping Ore storage Operation of ore handling plant Operation of other ancillary equipment Tailings disposal Reclamation Post-mining use of site
The checklist should consider whether or not these are involved and detail actions during each of the three stages of construction, operation and closure.
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identification methods, such as matrices, checklists or networks, may be used. The choice depends on the familiarity of the assessor with the methods. However, for cumulative impact assessment the most appropriate methodological approach should be one that is simple and yet comprehensive enough to provide a broad perspective (Canter and Kamath, 1995). Accordingly, a questionnaire checklist has been designed that would be the most suitable for identification and/or summarization of the cumulative impacts of opencast mining projects. The different columns of this checklist can be drawn up from Table 2 and will be helpful for identification of direct project-related impacts, the affected environment, the project–environment interactions, and other actions likely to affect the same resources affected Table 2. List of items for drawing up a questionnaire checklist to identify of project-related and cumulative impacts The first column of the checklist should consider the environmental impacts resulting from the project, looking at: Physical environment landform Landslide and land subsidence; soil erosion; change in existing topography Land use Alteration of existing or proposed land use of an area; impact on, or destruction of, wet land Air Impact on air quality due to gases, particulate etc Surface water Change in quantity of surface water; alter flow due to construction; destruction of streams; effects on water quality parameters Groundwater Alter the rate or direction of groundwater flow; alter the quality or quantity of groundwater; impact on recharge area or recharge rate Solid waste Impact existing landfill capacity Noise and vibration Expose people or wildlife to noise; ground vibrations Biological flora Change to the diversity or productivity of vegetation; impact on rare or endangered plant species; reduce acreage or create damage to any agricultural crop; impact forests Biological fauna Reduce habitat or the numbers of unique, rare or endangered bird or animal species; entrapment or impingement of animal life; impact on existing fish population; barrier to the migration or movement of animal or fish; cause emigration resulting in humanwildlife interaction problems Recreation Impact on fishing, boating, picnicking etc; creation of recreation opportunities Aesthetics Impact on scenic views; impact on unique physical features; impact on monuments Archeological Impact on destruction of historical, archeological, cultural and palaeontological sites or objects Health and safety Potential health hazards; risk of accidents from explosion, release of oil, radioactive materials, toxic substances etc Socio-economy Changes in income level; education; health care; change in existing cultural pattern; alteration of location or distribution of human population in the area; change in housing Transportation Changes in existing pattern of movements of men and materials The second column in the checklist would note whether these results would happen and the third column would note the affected resources. The fourth column would note whether other past, present or future non- project actions can affect any of the above
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CIA of opencast mining projects Table 3. Checklist for determination of impact significance during scoping
σy, σz are standard deviations of lateral and vertical concentration distribution respectively in meter and
A. An impact will be deemed to be significant if it has any of the following possible attributes: - Displacement or danger to any designated or protected environmental feature - Affecting many people - Cause for some proven chronic health effect
H is the effective release height in meters.
B. If the impact does not have any of the possible three attributes as above, consider the following questions: - Will there be a large change in environmental condition? - Will the impact extend over a large area? - Will it affect many receptors other than people (fauna, flora, facilities etc.)? - Will the impact be unusual or unique in the area? - Will the impact be permanent rather than temporary? - Will it be difficult to avoid, reduce, or mitigate the impact? - Will it cause cumulative impact? Sufficient details on these factors should be provided in the scoping checklist to state why the impact is considered to be significant or insignificant.
by the project-related impacts. However, the information on these other actions can only be incorporated into this checklist after taking into account the appropriate spatial and temporal boundaries of the assessment. The checklist contains a column that gives the significance of the identified impacts. The information in this column should be supplied using the checklist given in Table 3 that qualitatively determines the significance of the identified impacts based on a set of questions. This checklist has two components, A and B. Under component A, there are three questions to be asked for each of the identified impacts. If the impact has any of the attributes under component A, it is automatically deemed to be significant. If it does not satisfy any of these attributes, the impact should be evaluated based on the questions under component B. Sufficient details should be provided to decide why the impact is deemed to be significant or not. Air quality impact zone If pollutants are emitted from a point source, then the basic Gaussian plume model gives the concentration of pollutant at a point x meters downwind, y meters crosswind and at an elevation z meters with respect to the source as: C(x,y,z) = [QK/(2πuσyσz )][exp-0.5(y/σy)2] [exp-0.5((z–H)/σz)2+ exp-0.5((z+H)/σz)2]
(1)
where: C(x,y,z) is pollutant concentration at (x,y,z) in mass per unit volume Q is pollutant emission rate at (0,0,0) in mass per unit time K is a scaling coefficient to convert calculated concentrations to desired units (default value of 1×106 for Q in g/s and concentration in µg/m3) Impact Assessment and Project Appraisal September 2004
The plume spreads three-dimensionally into the atmosphere, thereby giving progressively reducing concentration values at increasing downwind and crosswind distances. When the receptor point is located at ground level (z=0), the concentration at the plume centerline (y=0) is given by: C(x,0,0) = [QK/(πuσyσz )]exp[-0.5(H/σz)2]
(2)
This concentration value at the plume centerline at any point on the downwind side is higher than at any point that is at crosswind distance y from the centerline for the same downwind distance. Therefore, for the purpose of determining the maximum distance up to which a pollutant can spread in the atmosphere, making conservative estimates, ground-level concentration at receptors downwind and on the centerline should be considered. σy and σz, the standard deviations of lateral and vertical concentration distribution can be calculated with the help of the following equations (Martin, 1976): σy = ax0.894
(3)
σz = cx d + f
(4)
The values of different constants are given in Table 4. The values of σy and σz are functions of the parameter ‘atmospheric stability’ categories. This parameter influences the movement of pollutants in the atmosphere and is a function of horizontal wind speed and vertical temperature structure of the atmosphere. While category A represents highly unstable atmospheric conditions when the greatest amount of spreading occurs, category F denotes the least amount of spreading under the most stable atmospheric conditions. For any project, the emission rate of suspended particulate matter (SPM), Q, is calculated following the emission rate formula for the overall mine as given in Table 5. The average release height of SPM above surrounding ground, H, is to be noted from the mine location details and the values of σy, σz for C stability category (which represents the average stability conditions) calculated using equation 3 and equation 4 respectively. With the calculated values of these parameters at different downwind distances x km, C(x,0,0) is calculated. When the value of C(x,0,0) becomes nearly 10 µg/m3, the corresponding x may be considered as the radius of the project impact zone. The value of 10 µg/m3 is chosen somewhat arbitrarily considering fact that the actual concentration will be much lower because of deposition along the pathway of travel and within vegetation layers. As a result, the air quality impact zone of the project that is calculated 239
CIA of opencast mining projects Table 4. Values of parameters for calculating standard deviation of concentration distribution
x ≤ 1km
Stability category
A B C D E F
a
c
d
213 156 104 68 50.5 34
440.8 106.6 61 33.2 22.8 14.35
1.941 1.149 0.911 0.725 0.678 0.740
x ≥ 1km f 9.27 3.3 0 –1.7 –1.3 –0.35
c
d
f
459.7 108.2 61 44.5 55.4 62.6
2.094 1.098 0.911 0.516 0.305 0.180
–9.6 2.0 0 –13.0 –34.0 –48.6
Source: Martin (1976)
by this method would be a conservative estimate only. Moreover, due consideration should be given to prominent wind directions too, since receptors located in the downwind directions of the project are far more likely to be affected by air pollution than the receptors located on the upwind side. The identified impact zone of each project may be delineated using the buffering capability of GIS and overlaid on Table 5. Empirical formula for emission rate of each activity in opencast mining projects
Activity
Empirical equation
Drilling
E= 0.0325 [{(100–m)su}/{(100–s)m}]0.1 (df)0.3
Overburden loading
E= [0.018{(100–m)/m}1.4 {s/(100–s)}0.4 (uhxl)0.1]
Coal/mineral loading
E=[{(100–m)/m}0.1{s/(100– s)}0.3h0.2{ul/(0.2+1.05u)}{xl/(15.4+0.87xl)}]
Haul road
E=[{(100–m)/m}0.8{s/(100– s)}0.1u0.3{2663+0.1(v+fc)}10–6]
Transport road
E=[{(100–m)s}/{m(100– s)}]0.1u1.6{1.64+0.01(v+fc)}10–6]
Overburden unloading
E=[1.76h0.5{(100–m)/m}0.2{s/(100–s)}2u0.8(cy)0.1]
Coal/mineral unloading
E=0.023[{(100–m)sh}/{m(100–s)}]2(u3cy)0.1
Exposed overburden dump
E=[{(100–m)/m}0.2{s/(100– s)}0.1{u/(2.6+120u)}{a/(0.2+276.5a)}]
Stock yard
E={(100–m)/m}0.1{s/(100– s)}{u/(71+43u)}[{cy/(329+7.6cy)}+{lx/(30+900lx)}]
0.4 2 0.3 Coal handling E=[{(100–m)/m} {a s/(100–s)} {u/(160+3.7u)}] plant
Workshop
E=[0.064{(100–m)/m}1.8{as/(100– s)}0.1{u/(0.01+5u)}10–4]
Exposed pit surface
E=[2.4{(100–m)/m}0.8{as/(100–s)}0.1{u/(4+66u)}10– 4 ]
Overall mine (for SPM)
E=[u0.4a0.2{9.7+0.01p+b/(4+0.3b)}]
Notes:
Source:
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m=moisture content (%), s=silt content u=wind speed (m/s), d=hole diameter (mm), f=frequency (no of holes/day), h=drop height (m), l=size of loader (m3), v=average vehicle speed (m/s), c=capacity of dumpers or unloader (t), a=area (km2), y=frequency of unloading (no/h), x=frequency of loading (no/h), p=coal/mineral production (Mt/year), b=OB handling (mm3/year) E=emission rate (gm/s) Chakrabarty et al (2002)
the resources map of the area to identify areas or other resources likely to be affected by air pollution. Analysis of impacts Scoping of impacts using the questionnaire checklist supported by GIS delineates some areas that are potentially vulnerable to cumulative impacts. The next requirement of CIA is to assess the effects of multiple actions on the resources over these areas. However, it is not necessary to predict the environmental impacts of future projects and activities in detail. Such assessments should be limited to the extent that is feasible and reasonable under the circumstances. One of the prerequisites of cumulative impact analysis is that, wherever possible, impacts should be quantified using some acceptable methods or tools. If cause and effect cannot be quantified, qualitative evaluation procedures may be used. This may happen frequently as many relationships are poorly understood and few site-specific data may be available (CEQ, 1997). Although mining projects can potentially affect many environmental resources, for the purpose of quantification of impacts in the current work, only air quality (SPM) has been considered. The focus of the current work has been more on the methodological aspect than on the validity or acceptability of any particular model. However, SPM concentrations can be best predicted using the Industrial Source Complex Short-term version 3 (ISCST3) model of the United States Environment Protection Agency (USEPA), which is a recommended model for regulatory purposes in simple terrain (USEPA, 2001). ISCST3 provides options to model emissions from a wide range of sources that might be present at a typical industrial source complex, including point, area, line and open pit sources. The particulate emissions in a typical opencast mine complex may result mainly from haul and transport roads, exposed overburden dumps or mineral stockpiles, drilling and loading operations in excavated pits and so on. ISCST3 can model emissions from all these sources with special provision for modeling of emission from open pit quarries. The model should be run twice. The first run would predict the SPM concentration at the receptors located within the impact zone of the project
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under study, while the second run would predict the concentrations at the receptors located within the cumulative impact zone.
Operation of the other mining projects in the vicinity and associated operations such as increased frequency of ore transportation were considered to be those that may contribute to cumulative impact on air quality with no consideration given to non-mining activities
Case study General information To illustrate the methodology developed for CIA in general and cumulative air quality impact in particular, a case study was conducted at Jilling Langalota (JL) iron ore mine in the Keonjhar district of Orissa in the eastern part of India. The mine is located in the thick of a mining belt with a cluster of mines around it indicating high potential for cumulative impacts. The lease area of the mine has common boundaries with Orissa Mining Corporation (OMC), Pattanayak Minerals (PMP), and N L Rungta (NLR) mines as shown in Figure 2. The mine uses a mechanized method of working — drilling and blasting, loading with frontend loaders, and transportation of ore and overburden in dumpers. An ore handling plant with crusher is installed within the lease area for rehandling of ore. The scope of the primary assessment was limited to the impacts arising from the construction, operation and closure of the mine itself along with the associated ore handling and transportation operations. The principal sources of SPM in a mining area are the emissions from various working areas in the mines. Accordingly, operation of the other mining projects in the vicinity and associated operations such as increased frequency of ore transportation were considered to be those that may contribute to
st re Fo ve er es R o ar K
Lakrhaghat Reserve Forest
d oa tR or p s an Tr
Barbil e n i yL a w l ai R
Thakurani Reserve Forest
st re Fo ev r e s e R ht a mah ddiS
Joda
JL Mine
r vie R PMP Mine a n u S
cumulative impact on air quality with no consideration given to non-mining activities. Although the JL mine is an operating mine, for the purpose of this work it was assumed to be a new project for which EIA would be required. The same also applies to the other mining projects considered for the assessment of cumulative impacts. This was necessary for two reasons, first, lack of availability of mines in the planning stage, and secondly, the propriety of information for such mines even when they are available. Consequently, this should be construed not as a full-scale impact assessment for actual projects but only as a demonstration of the developed methodology. Nevertheless, from the standpoint of scientific analysis, the study qualifies to be a representative tool to depict the outcome of the mining activities involved. Moreover, the study was based entirely on secondary information and no primary environmental
NLR Mine
B ai at r n i R e s e vre F o r e s t
OMC Mine i nr ati a B
River
LOCATION OF JL MINE 0.0
2.5
5.0
7.5
10.0
12.5 km
Figure 2. Location plan of JL, NLR, PMP and OMC mines
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data was generated. However, in some cases, the actual information was not available and some hypothetical data were considered without sacrificing the basic structure or purpose of the work. All the plans of the study area were prepared by digitizing the Survey of India topographic sheets of scale 1:50000 using Geomedia Professional 3.0 GIS software. Scoping for impact assessment The scoping process comprised of identifying the likely impacts of the JL mine, the environmental resources or human communities that can be potentially affected by these impacts, the potential cumulative impacts resulting from the operation of the mine in combination with the other mines, and the significant impacts requiring further attention in the later stages of the process. The various project actions that may result from the development, operation, and decommissioning of the JL mine were identified by drawing up a checklist using the items given in Table 1 and the resultant
checklist is presented in Table 6. After compilation of the columns in Table 6, based on the available secondary information, the following project actions for JL mine were identified: • change of land use within the lease area; • removal of a small portion of forest in the northern part of the lease; • construction of a power line from Banspani to the mine site; • groundwater removal for washing and drinking purposes; • construction of office and other buildings; • provision of water supply, medical as well as welfare facilities; • provision of direct and indirect job opportunities; • surface run off from the hills; • removal and storage of top soil outside the ultimate pit limit; • overburden (OB) removal by drilling-blasting and loading at pit; • ore removal by drilling-blasting and loading at pit; • disposal of solid waste generated at the colony;
Table 6. Checklist for identification of project components of JL mine
Will the project involve the following major activities?
Yes/No Details of action
Stage of occurrence
Land acquisition and creation of new land use
Yes
Removal of vegetation
Yes
Demolition of important structures Impoundment, culverting, realignment or other changes to the hydrology of the water courses Closure/diversion of existing transport route or creation of new transport route Closure/diversion of other utilities or creation of new utilities such as power line, pipeline Ground water removal
No No
Land acquisition will lead to change of land use within Construction the lease area A small portion of forest land on the northern part of the Operation lease will be removed No such structures exist No such changes will be required
No
The road to the area exists
Yes
Power line will be constructed from Banspani
Operation
Yes
Ground water will be drawn for drinking and cleaning purposes Office and other buildings will be constructed
Construction/operation
Civil construction work for surface or underground structures Provision of civic amenities such as housing, school, medical facilities, water Provision of direct or indirect employment opportunities Surface run off Topsoil and subsoil removal and storage
Yes Yes
Overburden removal and loading at pit
Yes
Ore removal and loading at pit
Yes
Disposal of solid waste Disposal of liquid effluents Overburden transportation from pit
Yes Yes Yes
Ore transportation from pit
Yes
Overburden dumping Ore storage Operation of ore handling plant Operation of other ancillary equipment
Yes Yes Yes No
Tailings disposal Reclamation
No Yes
Post-mining use of the site
No
242
Yes Yes Yes
Operation
Power, housing, water supply and a small medical Construction/operation facility shall be provided at the mine The project will involve creation of direct and indirect Construction/operation jobs Rainwater will flow down the hill mainly towards the East Construction/operation Soil will be removed and stored separately outside Operation the ultimate pit limit Overburden will be removed by drilling and blasting. Operation Blasted OB will be loaded into dumpers by shovels Ore will be removed by drilling and blasting. Blasted Operation OB will be loaded into dumpers by shovels Solid waste will mainly come from the colony Operation Effluents will mainly generate from workshop Operation Overburden transportation will be limited from the Operation working pits to the dumps Ore will be transported from pit to OHP and from OHP Operation to railway siding Separate overburden dumps will be created Operation Ore storage facility will be maintained beside the OHP Operation An OHP will be in operation Operation No other ancillary equipment will operate other than the dozers No tailings will be generated Backfilling of the waste will cover a portion of the Closure excavated pit and vegetation will grow over it No such planning has been done
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• disposal of liquid effluents generated from the workshop; • overburden transportation from pit to dumps; • ore transportation from pit to railway siding via ore handling plant (OHP); • dumping of OB; • ore storage facility; • operation of OHP; • backfilling of the waste to cover a portion of the depression and revegetation; Almost all the activities arising from construction, operation, or closure of the JL mine are likely to cause impacts on the surrounding environment, both beneficial and adverse. The next step is to identify these project-related impacts and the affected resources. The items in Table 2 were used to draw up a questionnaire checklist for identification of direct project-related impacts, the affected environment and, for each of the identified impacts, where the components of the project and environment interact. The first three columns of the resultant checklist given in Table 7 contain this information. The fourth column helped in identification of the actions from other projects that may cumulatively affect the same resources affected by the JL mine. The probable project-related impacts of the mine, both adverse and beneficial, as identified thorough Table 7 are: • soil erosion in the area resulting from removal of topsoil and vegetation aided by natural precipitation; • temporary change in topography of the area; • change in land use in the area resulting from land acquisition; • air pollution, mainly from particulate, in the surrounding villages as a result of a number of activities such as top soil removal and storage, OB and ore removal, loading and transportation, OB dumping, and the operation of ore handling plant; • destruction of some natural drains resulting mainly from top soil removal; • deterioration in the water quality of the Dalko nalla and Baitarani river system as the surface run off may carry sediments and workshop effluents may contain oil and grease; • alteration in groundwater availability due to withdrawal; • noise pollution from the operation of machines and trucks in the villages and forest areas surrounding the mine and transport road resulting from ore and OB removal, loading and transportation, and operation of the ore handling plant; • blast-induced ground vibrations; • damage to agricultural crop productivity in the surrounding villages from particulate deposition in agricultural land and degradation of surface water quality as agriculture is dependent on surface water; • impact to Baitarani forest lying north of the lease resulting from removal of vegetation; • impingement on animal life in the forest from Impact Assessment and Project Appraisal September 2004
• • • • • • • •
increased noise and blast-induced ground vibrations; barrier to the migration route of elephants as the ore transportation through the transport route and railway line would run through the forests; emigration of elephant community in the villages since the migration route and habitat of the elephants would be disturbed; visual impact from vegetation removal, topsoil removal and the external dumps; health hazard to the villagers from air pollution and increased noise level; risk of accidents as a result of increased traffic movement on the road; increase in the income level of the local community from direct and indirect employment; access to better health care facilities to the local population; alteration in the population distribution in the area as many outside people may be employed.
In a situation where all the four mines are located in close proximity, it is likely that the project-related impacts of the JL mine would also lead to cumulative impacts in the area. Accordingly, it is seen from the fourth column of Table 7 that the impacts of the project actions in the other three mines combine with the impacts of the JL mine in a synergistic manner resulting in cumulative impacts in the area for most of the environmental resources. However, all these impacts may not be significant warranting further attention during subsequent phases of the EIA process. For identification of the probable significant impacts the criteria set out in Table 3 were applied in the last column of Table 7 and the significant adverse impacts identified through the process are: • large-scale soil erosion in the hills of the region; • air pollution in the villages of the area; • deterioration of the water quality of Baitarani river; • exposure of villagers to increased noise level; • potential health hazard to the villagers. The focus of the current work was on air quality impact assessment. The villages that could be vulnerable to air pollution and those where the effect of
The focus was on air quality impact assessment: the villages that could be vulnerable to air pollution and those where the effect of air pollution could be cumulative were identified through the delineation of air quality impact zones
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CIA of opencast mining projects Table 7. Questionnaire checklist for identification of environmental impacts of JL mine and cumulative impacts
Will the project actions result in any of the following impacts? Physical environment landform Landslide and land subsidence Erosion of soil due to increased wind, flood, removal of vegetation Change in existing topography
Land use Alteration of existing or proposed land use of an area Impact on or destruction of, wetland Air Impact of air quality due to gases, particulate etc
Surface water Change in quantity of surface water Alter flows due to construction Destruction of streams
Effect on water quality parameters
Ground water Alter the rate and direction of ground water flow Alter the quality of ground water
Alter the quantity of ground water
Yes/no/maybe and reasons for the same
If yes or maybe, the resource or area to be affected
Other past, present, or Is the impact likely to be future actions that may significant? Why? contribute to the impact
No: available information does not support this Yes: removal of vegetation Lease area and topsoil removal aided by natural precipitation may cause erosion of soil Yes: existing topography of Lease area the area will change temporarily
Topsoil removal at other mines may contribute to soil erosion
Yes: t he rate of erosion may be substantial and the impact is cumulative
Working at other mines will change the local topography
Not likely: although the effect may be large, regional, and cumulative, it will be temporary
Yes: land use within the Lease area lease area will be affected, as land will be acquired for mining purpose
The combined effect of all the mines will result in change of existing land use in the entire area
Not likely: the change may be regional and cumulative but does not interfere with future land use planning in the area
Area lying within the air Yes: air quality in the surrounding area may quality impact zone deteriorate due to particulate emissions from a number of activities
The villages within the cumulative air quality impact zone will experience cumulative impact
Yes: the magnitude of the impact may be large and may extend regionally or affect many receptors; however, mitigation of the impact is possible with known environmental management solutions
No: no surface watercourse will be harnessed No: no surface water system will be diverted Maybe: some small natural Top and slope of the hills drains within the leasehold may be disturbed
The other mines may contribute to such impact in the area
No: the change will be very nominal, affecting only a part of the plateau; it will not affect many other resources Maybe: the change may be substantial, affecting the regional water quality, though some mitigation is possible with practicable management systems
No: no wetland exists in the area
Baitarani river system Yes: surface run off and effluent water will flow mainly down the hill slopes and join the Baitarani river system carrying suspended particles; moreover, the soil erosion may also increase the sediment load in the streams No: water table occurs well below the quarry floor level No: ground water is unlikely to be affected by seepage and leaching of minerals due to the presence of an impervious layer Maybe: the daily Water table in the area requirement of water will be met entirely from the ground water withdrawal
Impact on recharge area or recharge rate
No: ground water recharge area will not be affected
Solid waste Impact existing land fill capacity due to filling by solid waste
No: the existing land is not used for filling by other materials
The other mines may contribute to the pollutant load on the river system
Ground water withdrawal at other mines may affect groundwater availability in the area
Maybe: the change may be substantial, extend regionally, affect many people, and may be cumulative in nature
(continued)
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CIA of opencast mining projects Table 7 (continued) Will the project actions result in any of the following impacts? Noise and vibration Expose people or wildlife to noise
Ground vibrations
Yes/no/maybe and reasons for the same
If yes or maybe, the resource or area to be affected
Yes: some of the Noise impact zone surrounding villages and surrounding the mine and the animal life in the forests transport road will be exposed to noise from the operations of various machines in the mine and trucks on the transport road Yes: blasting will induce Structures in the nearby ground vibrations in the villages area
Biological flora Change to the diversity or No: the vegetation removal productivity of vegetation is not likely to change the diversity or productivity of vegetation in the forestland Impact on rare or No: no such species exist endangered plant species Agricultural land in the Reduce acreage or create Yes: some part of the damage to any agricultural lease area is agricultural villages lying within the project impact zone crop land, and the effect of particulate deposition and degradation of water quality in the Dalko nalla may result in a reduction in the crop production Impact forests Yes: vegetation removal Forestland North of the will cause reduction in the lease forestland
Other past, present, or Is the impact likely to be future actions that may significant? Why? contribute to the impact
Extraction and transport operations of other mines will affect some the receptors
Yes: the change may be substantial, affecting many receptors, extending regionally and may cause cumulative impacts in certain areas
Though blasting will be carried out at other mines the effects are not synergistic
Not likely: with modern blasting technology the effect is likely to be small, localized, easy to mitigate, and non-cumulative
Similar impacts from the Not likely: the effect of deposition on the crop yield other mines may also affect the agricultural land is expected to be low, and it will not affect other resources, will not be difficult to mitigate at source None: other mines will not No: the change is very be located in forestland small, localized, easy to mitigate, and no potential for cumulative impacts
Biological fauna Reduce habitat or the No: the area is not numbers of unique, rare or inhabited by such wildlife endangered species of bird and animals Entrapment or Yes: noise and vibrations Reserve forests in the area Similar effects from the impingement of animal life may affect the animal life in other mines the forest Impact on existing fish population Create barrier to the migration or movement of animal or fish Cause emigration resulting in human– wildlife interaction problem
No: no fish breeding area exists nearby Yes: transportation through Reserve forests in the area railways and road may create barrier to the migration route of elephants Yes: habitat reduction and Villages in the area barrier to their migration routes may cause elephants to emigrate into the villages
Not likely: the combined level of noise and vibrations in the forests is likely to be low, localized, and easy to mitigate
None, as transportation of Not likely: the effect is ore from other mines will local, easy to mitigate, and be through the same non-cumulative route None, as transportation of ore from other mines will be through the same route
Not likely; habitat reduction is small, localized, and non-cumulative
Topsoil removal and dumping in other mines will contribute to cumulative impacts in the area
Not likely: the effect may be substantial, regional, and cumulative; however, the impact is temporary only
Recreation Impacts of fishing, boating No: the lease area is not or picnicking etc part of a tourist spot Creation of recreation No: no such plan exists opportunities Aesthetics Impact of scene views
Yes: vegetation removal, Lease area topsoil removal, and dumps will create visual impact in the area
Impact on unique physical No: no such features exist features Impact on monuments No: no such structures exist (continued)
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CIA of opencast mining projects Table 7 (continued) Will the project actions result in any of the following impacts?
Yes/no/maybe and reasons for the same
If yes or maybe, the resource or area to be affected
Other past, present, or Is the impact likely to be future actions that may significant? Why? contribute to the impact
Archaeological Impact on, or destruction No: no such objects exist of, historical, archeological, cultural and palaeontological sites or objects Health and safety Potential health hazards
Risk of accidents due to explosion, release of oil, radioactive materials, toxic substance etc Socio-economy Changes in income level Education level Health care
Change in existing cultural pattern Alteration of location or distribution of human population in the area Change in housing
Transportation Changes in existing pattern of movements of men and material
Maybe: the health hazards Villagers in the villages to the villagers may come lying within the air quality from exposure to dust and and noise impact zones noise
Similar effects from other mines may contribute to cumulative impacts
Transport road Maybe: increased frequency of vehicle movement in the road may lead to accidents
Ore transportation from other mines will also contribute to increased traffic flow
Yes: new direct and indirect job opportunities will be created No: no education facility will be created Yes: health care facilities will be provided to the villagers
Local economy
The other mines will also contribute to the increase in income level
Yes: the impact is beneficial and benefits the entire local community
Local community
Creation of medical facilities in some of the other mines may benefit the local community
Yes: the impact is beneficial and benefits the entire local community
No: no such change is envisaged Yes: deployment of outside Local community laborers may change the demography of the area No: housing will be provided for employees only
Maybe: if the values of the particulate concentration or noise are high enough, this may affect many receptors, and cause cumulative impacts Not likely: the impact is not unusual and is not unique to the area.
Similar deployment in other Not likely: the change mines may contribute to would be small the change in demography
No: the road already exists
air pollution could be cumulative were identified through the delineation of air quality impact zones. The air quality impact zones were calculated based on the approach explained previously and are presented for all four mines in Table 8. The impact zones were delineated using the buffering capability of GIS software and overlaid on the receptor map as shown in Figure 3. As seen from the figure, of the 22 villages within the study area, 21 lie within the air quality impact zone of the JL mine, while 19 fall within the impact zones of all the mines, that is, the cumulative air quality impact zone. Since the
boundaries of the impact zones are only approximate these should serve only as rough estimates. Although all these villages may be potentially subjected to cumulative impacts, in practice, the level of impacts may not be significant for villages lying in the upwind directions. However, no significant Table 7. Questionnaire checklist for identification of environmental impacts of JL mine and cumulative impacts prominent wind directions could be identified from the available meteorological data. Hence, cumulative air quality assessment should be done for all 19 villages.
Table 8. Calculation of air quality impact zones for JL, OMC, NLR and PMP mines
Mine name
Average wind speed (m/s)
a
c
d
f
Sigma Y (m)
Sigma Z (m)
H (m)
Q (gm/s)
JL OMC NLR PMP
2.00 2.00 2.00 2.00
104 104 104 104
61.0 61.0 61.0 61.0
0.911 0.911 0.911 0.911
0.0 0.0 0.0 0.0
546.71 592.31 561.96 469.67
330.95 359.10 340.36 283.89
10 10 10 10
17.6 20.6 19.0 12.7
246
C Impact zone (microgram/m3) (km) 9.67 9.63 9.88 9.48
6.4 7.0 6.6 5.4
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CIA of opencast mining projects Kamarjora Inganijaran Bicchakundi Khuntapani Banshapani
Sargitalia Air quality impact zone for JL Mine
Chilkapata Jalhari
JL Mine
Bholberha
Jururhi Khandabandh
Jajang 1 Jajang 2
Jaribahal
NLR Mine Bandhuaberha
Gurda PMP Mine Palsha 1
Air quality impact zone for NLR Mine Kamalpur
Guruthan Bamebari
Palsha 2 OMC Mine
Bhandaridihi Air quality impact zone for PMP Mine
Air quality impact zone for OMC Mine
0.0
1.5
3.0
4.5
6.0
7.5 km
Figure 3. Air quality impact zones of JL, NLR, PMP, and OMC
Air quality impact analysis The SPM concentrations at the villages around the JL mine were predicted using the ISCST3 model. The model was run twice, once assuming the functioning of the JL mine alone and then assuming the functioning of the other mines — OMC, PMP, and NLR — jointly with the JL mine. The data input to the model are: Source data The source data required as model input are the locations of various sources of SPM in the mines, their dimensions and emission rates. For cumulative impact assessment it is sufficient to have only approximate locational and design information for the other mines since detailed designs may not be available at the stage. Location and dimension details were obtained from the digitized maps in GIS. Emission rates for different types of sources were calculated using formulae given in Table 5. Since the ISCST3 model accepts area and open pit sources as rectangles with aspect ratio not exceeding 10:1, these sources were approximated as rectangles without much of change in the area or location. Haul and transport roads were also approximated into a number of area segments assuming the width to be around 10 meters for haul roads and 20 meters for transport roads. In addition, there are a number of point sources in the mines. However, these are not true point sources as per the definition of different sources given in the model. Rather, they can be assumed to be part of the emissions from the corresponding area or open pit sources and calculated emission rates from these sources were added to the corresponding area or
Impact Assessment and Project Appraisal September 2004
open pit sources where they are located. The approximated sources for modeling purpose are shown in Figure 4 for all the mines. Receptor data Locations of various villages around the mine were taken from the GIS database while the data on the intervening terrain were taken from the Survey of India topographic sheet of the area. Meteorological data Hourly records of meteorological parameters, such as wind speed and direction, and temperature, were collected from the environmental data records as available with the mines’ authority. Data on hourly mixing heights and stability classes were taken from published literature (NEERI, 1990). However, some special meteorological data such as Monin-Obukov length, surface friction length and surface friction velocity are required for modeling of open pit sources. These were processed from the basic meteorological data using the PCRAMMET meteorological data processing utility of USEPA. The first 24 hours of meteorological data used in the model are shown in Table 9. Using all this information, the input ‘runstream’ files were created and the model was run. The predicted emission level information for all the receptors within the study area both for the JL mine alone and cumulative sources are given in Table 10. It can be seen that the predicted 24-hour average SPM concentrations considering emissions from the JL mine alone at most of the villages would be low. However, at three of the villages — Khuntapani, Jalhari, and Jururhi — situated near the mine these are expected to be around 299 microgram/m3, 179 microgram/ m3, and 260 microgram/ m3 respectively. 247
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N
Drilling point (15) OB loading point (10) OB unload point (9) Ore loading point (10) Ore unload point (4) Railway siding (1) Haul road (158) Ore handling plant (4) Transport road (91) OB dump (32) Open pit quarry (14) Lease area (4)
0.00
0.75
1.50
2.25 3.00
3.75 km
Figure 4. Sources of emission in JL, NLR, PMP, and OMC mines for modeling
Since no baseline data were available for these villages, we used 100 microgram/ m3, which is a typical value for rural areas in India. This means that the total concentration at these villages would exceed the maximum allowable 24-hour average concentration of 200 microgram/m3 for rural areas set out in the National Ambient Air Quality Standards. However, the cumulative concentration values at many of the villages would be quite high compared to their values when the impact of the JL mine alone is considered. This is more pronounced in the villages of Banshpani, Khuntapani, Chilkapata, Jalhari, Jurhuri, Jaribahal, Jajang 1, Bamebari, Palsha 1, Kamarjhora, and Palsha 2. This is mainly because of a large increase in the regional emission level when all four mines are in operation. Moreover, at Banshpani, Jaribahal, Jajang 1, Bamebari, and Palsha 1, the concentrations resulting from the JL mine alone are insignificant, but, when the effects of all the mines are considered, they become quite significant. The SPM concentration values given in Table 10 are predicted values only, based on the assumption of the validity of both the ISCST3 model itself and the emission rates and other data input into it. Moreover, the prediction is based on the worst-case scenario, considering all the possible sources emitting particulate at the same time. Also, the meteorological 248
data were taken for one season only and the deposition of particulate in the intervening terrain was not considered. All these factors make the prediction a little pessimistic. Therefore, the actual level of SPM may be lower than these predicted values. Nevertheless, this may serve as a representation of the actual condition.
Discussion The main objective of the proposed methodology is to suggest the practical means of addressing cumulative impacts within the general EIA framework. Application of the proposed methodology to the case study reveals some of the important benefits and successes of the methodology in attaining its stated objective. Scoping, as demonstrated here, was carried out effectively using the questionnaire checklist and GIS. The process yielded both the project-related impacts and identified the important resources where potential cumulative impacts may result. The method could also identify the more important impacts that would warrant further attention during the subsequent phases of the assessment. The modeling of different environmental components has progressed a great deal during the last few
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CIA of opencast mining projects Table 9. First 24-hour meteorological data for ISCT3 model run
Hour Flow vector (Degree) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
225 225 225 225 270 270 292.5 360 45 22.5 360 337.5 315 315 0 0 0 0 0 0 0 0 0 0
Air velocity Temperature (m/s) (K) 0.53 1 1.17 1.2 1.17 0.94 0.78 0.92 0.81 0.75 0.78 0.56 0.53 0.5 0 0 0 0 0 0 0 0 0 0
Stability
288 289.5 293 297 303 307 308.5 309 308 307 300 297 294.5 293 293 292.5 292 292 291.5 289.5 288 288 288 288.5
Mixing height (m)
4 4 3 2 2 2 2 1 1 1 1 2 2 2 3 3 4 4 4 4 5 5 5 5
years. The analysis of air quality impacts was facilitated by the proper use of models such as the ISCST3 model used here because it has provisions for specifically addressing the emissions from opencast mines. Also, the use of GIS, as demonstrated here, could be quite beneficial to CIA not only during scoping for delineation of impact zones but during the analysis phase as well. However, the methodology as applied to the case study has its fair share of shortcomings. First, it requires a set of data for its proper demonstration, but data availability has been a key factor preventing the application of the methodology to the case study to Table 10. Predicted 24-hour average SPM values at different villages from JL mine alone and all mines combined
Name of village Banshapani Khuntapani Sargitalia Chilkapata Jalhari Bholberha Jururhi Khandabandh Jaribahal Jajang 1 Bandhuaberha Kamalpur Gurutuan Bhandaridihi Bamebari Palsha 1 Gurda Jajang 2 Palsha 2
From JL mine alone (micrograms/m3) 15 299 5 9 179 51 260 71 55 42 6 4 3 1 0 2 5 10 3
All mines combined (micrograms/m3) 109 409 19 82 277 72 348 76 226 634 13 5 7 5 254 245 64 33 58
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600 600 700 800 1000 1100 1200 1400 1400 1400 1200 1000 800 800 700 600 500 500 400 400 500 500 500 500
Friction velocity (m/s) 0.0367 0.0378 0.0378 0.0378 0.0378 0.0378 0.0367 0.0378 0.2325 0.2479 0.2543 0.2579 0.2557 0.2478 0 0 0 0 0 0 0 0 0 0
M-O length Surface roughness (m) length (m) 2 2 2 2 2 2 2 2 –28.2 –16.2 –14.2 –13.2 –13.8 –16.3 0 0 0 0 0 0 0 0 0 0
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
its fullest extent. The deficiency of data started with the choice of site. Since no mine in the planning stage was available for application of the methodology, it was applied on operating mines only. Therefore, the case studies incorporated in the work, while adequately demonstrating the efficiency of the developed methodology, cannot be treated as a full-scale impact assessment. The ISCST3 model used in the study is a model developed in the USA. Although it has provisions for predicting the effects of emissions from opencast mines, it has not been validated in Indian conditions. The Geomedia Professional software used in the study is a vector GIS: although it is adequate for carrying out the tasks as detailed, to utilize the full potential of GIS for impact assessment and especially for visual presentation of the results, software with raster capability is preferable. With this capability, digital elevation models or isopleths of the concentration values could have been generated.
Conclusion The proposed methodology seeks to suggest ways through which the CIA of opencast mining projects in general, and cumulative air quality impact assessment in particular, can be carried out in a simple yet effective manner. Specifically, the method deals with the practical means of addressing cumulative impacts within the general EIA framework. Two issues have been given special attention in the process — scoping and analysis of impacts. For identification of cumulative impacts during scoping, the use of questionnaire checklists has been suggested. To supplement the impact identification process, a 249
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practical way of delineating project impact zones for air quality using GIS has also been described. Analysis of air quality impact for opencast mining projects, it has been argued, should be done through the proper use of models such as ISCST3. Cumulative impact assessment has been made an integral part of EIA legislative requirements in many nations across the world. However, in India, this requirement has still not been incorporated in the EIA notifications of the Ministry of Environment and Forests. As the study reveals, many of the detrimental environmental impacts may occur by not properly addressing the potential of cumulative impacts. It is recommended that in future cumulative impacts should be included in the EIA process in India as it leads to best practice, enhances the effectiveness of EIA by aiding in the decision-making process, and finally contributes to sustainable development.
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CEQ, Council on Environmental Quality (1997), “Considering cumulative effects under the National Environmental Policy Act”, Council on Environmental Quality, Executive Office of the President, Washington DC, available at , last accessed January 2003. Chakraborty, M K, M Ahmad, R S Singh, D Pal, C Bandopadhyay and S K Chaulya (2002), “Determination of the emission rate from various opencast mining operations”, Environmental Modeling and Software, 17, pages 467–480. ECDGXI, European Commission Director General XI (Environment, Nuclear Safety and Civil Protection) (1999), “Guidelines for the assessment of indirect and cumulative impacts as well as impact interactions”, available at , last accessed January 2003. Everitt, B (1995), “Scoping of environmental impact assessments”, paper presented to EIA Process Strengthening Workshop, Canberra, 4–7 April. Hilden, M (1996), “Evaluation of the significance of environmental impacts”, paper presented to EIA Process Strengthening Workshop, Canberra, 4–7 April. Mahatha, S, and P Dutta (2003), “Incorporating cumulative impact concerns into EIAs”, Mining Environmental Management, 11(2), pages 16–21. Martin, D O (1976), “Comment on ‘The change of concentration standard deviations with distance’”, Journal of Air Pollution Control Association, 26, pages 145–147. NEERI, National Environmental Engineering Research Institute (1990), “Comprehensive environmental impact assessment of Manuguru coalfields”, NEERI, Nagpur, India. Sadler, B (1996), “International study of the effectiveness of environmental assessment”, Final Report — Environmental assessment in a changing world: evaluating practice to improve performance, available at , last accessed January 2003. USEPA, United States Environment Protection Agency (2001), “Guidelines on air quality models”, USEPA, 40 CFR, Part 51, Appendix W.
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