Comprehensive Environmental Impact Assessment Report for Darlipali Super Thermal Power Project, Stage-I (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 1 of 25
CHAPTER - IV
ANTICIPATED ENVIRONMENTAL IMPACTS AND MITIGATION MEASURES 4.0
INTRODUCTION
An impact on environment is an alteration of the environmental conditions or creation of new set of environmental conditions, adverse or beneficial, caused or induced by the action or a set of actions under consideration. Impact Assessment is the identification, prediction and evaluation of environmental impact whether adverse or beneficial due to each of the activity of proposed project. This chapter describes the possible impacts due to the proposed integrated thermal power plant on each and every component of environment like air, water, noise, soil, etc. in the study area and mitigation measures adopted to reduce the impacts on environment. Environmental impacts are categorised as either primary or secondary. Primary impacts are those which are attributed directly by the project. Secondary impacts are those that are induced indirectly and typically include the associated investment and changed patterns of social and economic activities by the proposed action. Quantification of assessments in terms of measurable units would be the ideal method for impact assessment. Mathematical models are the best tools to quantitatively describe cause-effect relationships between sources of pollution and different components of environment. However, due to lack of information/data, uncertainties involved and complex interrelationships between various sectors of environment, it is not always possible or at least not easily achievable. In such cases, only qualitative predictions have been made based on experience and judgments. The present study uses a Simulation Model for Atmospheric Dispersion of Stack Emissions [Industrial Source Complex Version 99155 (ISC3) of USEPA] for prediction of ambient air quality due to operation of Darlipali STPP and “multisource noise attenuation model” for dispersion of noise. Adequacy of proposed mitigation measures has been evaluated against predicted environmental impacts and various standards notified by MoEF under the Environment (Protection) Act, 1986 and other relevant standards/ criteria published by Bureau of Indian Standards/ other agencies. Further, mitigatory measures, if necessary have been suggested in environmental management plan. As a first step, the entire power generation process has been divided into a number of smaller sub-activities for construction and operation phases. The probable 4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 2 of 25
impacts of each of these activities on various sectors of environment (such as air, water, soil, biotic, socio-economic environment etc.) have been identified and listed. Table 4 (a) and 4 (b) list various activities of construction and operation phase and their probable impacts on various sectors of environment. The impacts are classified as long term and short term impacts. The short term impacts are envisaged to be confined to construction period only. Mitigation measures for significant impacts are discussed in respective sections. Table 4 (a): Identification of Construction Activities & Probable Impacts Construction Activities
Sector
A) Long Term Impacts: Land Land Acquisition Socioeconomics B) Short Term Impacts: Site clearing Air and Leveling (cutting, stripping, Water excavation, Land earth movement, Ecology compaction) Transportation and Storage of Construction Material/ Equipment
Civil Construction Activities Mech. & Elec. Erection Activities Influx of Labour & Constn. of Temp. Houses
Air
Water Soil Public Utilities Air Water Air Water Socioeconomic s Land
Probable Impacts
• Direct Change in Land Use Pattern • Change in land use pattern in the vicinity • Displacements and Loss of livelihood
• Fugitive Dust Emissions • Noise/ Air Emissions from construction equipment & machinery • Run-off from construction area • Loss of fertile top soil • Change in Drainage Pattern • Loss of vegetation/ habitat • Topographic Transformations • Noise and Air Emissions from Vehicles • Fugitive Dust Emissions due to Traffic Movement • Spillage and fugitive emissions of construction materials • Spillage of construction material and flow into streams • Run-off from Storage Areas of Construction Material • Deposition of spilled construction material on soil • Increased flow of traffic • Congestion on roads • Noise and Air Emissions from Construction Machinery • Fugitive Dust Emissions due to Movement of Traffic • Run-off from Construction Areas containing Construction Material • Noise & Air Emissions from Machines/ activities • Run-off from Erection Areas containing Oils, Paints • Stress on infrastructure • Stress on social relations • Change in land use pattern of the area in labour colonies
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Transportation and Disposal of Construction Debris
Water Air
Water
Soil
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 3 of 25
• • • • •
Sanitary effluents from labour colonies Noise and Air Emissions from Transport Vehicles Fugitive Dust Emissions due to Movement of Traffic Spillage and fugitive emissions of debris materials Spillage/ spread of debris material and flow into streams • Run-off from Disposal Areas • Spillage/ spread/ deposition of debris • Conversion of land into waste land
Table 4 (b) lists various activities of operation and maintenance phase and their probable impacts on various sectors of environment. Most of these impacts are long term impacts. However, the significance of most of these impacts are envisaged to be low, as discussed in the following sections. Table 4 (b) Identification of Operation and Maintenance Activities and Probable Impacts Operation and Maintenance Activities Transportation of Coal/ Oil
Unloading, Crushing and Storage of Crushed Coal/ Unloading and Storage of Oil
Burning of Fuel Withdrawal of Water
Water Treatment for various uses
Power Cycle
Sector
Air
Water Public Utilities Air
Water
Air Water
Ecology Water
Water
Probable Impacts • • • • • • • •
Noise and Air Emissions from Vehicles Fugitive Dust Emissions due to Traffic Movement Spillage and fugitive emissions of coal/ oil Spillage of coal/ oil and flow into streams Increased flow of traffic Congestion on roads Noise and Air Emissions from Vehicles Fugitive Dust Emissions from Coal Handling Areas • Effluents for CHP/ Oil Storage Areas • Effluents from Dust Extraction/ Suppression systems • Run-off from Coal Stock Yard
• Stack emissions (TSPM, RSPM, SO2, NOx) • Reduced availability to downstream users • Reduced flow in downstream direction/ change in regime • Entrapment/ Impingement of Organisms • Generation of Effluents and Sludges from Treatment Plant • Clarifier Sludge • Filter Backwash • DM Plant Regeneration Waste • Tube Settler Sludge • Discharge of Blowdown
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW) Equipment Cooling Transportation, Storage & Use of Chemicals/ Cl2 Transportation and Disposal of Ash Operation of Transformers and Switchyard Maintenance (Cleaning, Overhaul, Oil Change, Lubrication etc.) Domestic Use of Water in Plant and Township
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 4 of 25
Water/ Ecology Air/ Water
• Discharge of Hot Water containing chemical biocide • Risks of Accidental spillage/ waste of chemicals
Land Air
• Land requirement for ash disposal • Fugitive Emissions
Water
• Generation of effluents containing oil
Water
• Generation of effluents containing oil/ chemicals
Water
• Generation of sanitary effluents
The impacts due to construction will be on smaller scale and limited to construction phase. Construction phase impacts are mainly related to levelling of site, construction and erection of plant equipment and other related structures. The impacts during construction and operation phase on various environmental domains are described in the following sections.
4.1
Land use and Topography
The main power plant, ash disposal area, township, greenbelt and other facilities is proposed to be located within an area of 1270 acres. This will lead to changes in land-use pattern in and around the proposed project. The construction activity would bring immediate changes in the land use pattern of the proposed plant area as well as in the vicinity. The land required for the project will undergo a change due to cutting, stripping, excavation, and levelling, landscaping, loss of vegetative cover and erection of structures of the proposed project. The proposed project area is agricultural and Government land and has flat terrain slightly sloping towards south west. The impact on land use will be long term and permanent. The construction activities would attract a sizeable population and influx of population is likely to be associated with construction of temporary hutment for construction work force. However, this will be only a temporary change and shall be restricted to construction period. As soon as the construction phase is over, the land use pattern modified to meet the requirement of construction phase shall be reversed. Development activity also induces changes in land use pattern of the adjoining areas because of the increased availability of infrastructural facilities, increase in commercial value of land etc.
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
4.2
Soil
4.2.1
Construction phase
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 5 of 25
Construction activities involving levelling, excavation and removal of existing vegetation would invariably disturb the soil of the area. The impacts on soil during construction phase shall be mainly due to loss of top soil in the construction areas and contamination of the soils of surrounding area due to construction materials such as cement, sand, oils, etc. The disturbances would be more pronounced during the summer and monsoon seasons with strong rains. However, it shall be temporary and shall be confined to the areas of construction only. Generally, such disturbances are confined to the area of activity i.e. the main plant, town ship and ash disposal area. Appropriate soil conservation measures associated with improved construction techniques would minimize such impacts. Timely afforestation activities would also contribute positively towards soil conservation. 4.2.2 Operation Impact: The impact on the soil during operation of the project could result due to deposition of residual particulate matter and gaseous emissions on the soil. The impact on the soil due to operation of the power plant and gaseous emissions would be negligible. However, it is advisable to undertake periodic monitoring of soils at the maximum impact zone of the pollutants mentioned above. 4.3
HYDROLOGY AND WATER USE
4.3.1
Impact on Surface Water
The water for the project will be drawn from Hirakud Reservoir on Mahanadi river. The entire water requirement including cooling water, plant water, ash water and domestic water is estimated to be 4750 m3/hr with ash water recirculation and 5857 m3/hr with once through ash water system. Department of Water Resources, Govt of Orissa has accorded water commitment for the project considering the requirement of other users. Therefore, it is anticipated that there will be no impact on the availability of water to the other users. 4.3.2 Ground Water As no ground water is proposed to be extracted for the project, the construction and operation of the project will have no impact on the ground water potential of the study area. 4.4
AIR QUALITY
This chapter presents identification and assessment of various impacts on air quality from the proposed project in the study area. The details on impacts of the project activity on air environment are discussed below: 4.4.1
Impact during Construction Phase
This includes the following activities related to levelling of site, construction and erection of plant components. 4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 6 of 25
Impacts of construction activities on air quality are cause for concern mainly in the dry months due to dust particles. The main sources of emission during the construction period are the movement of equipment at site and dust emitted during the leveling, grading, earthworks, foundation works and other construction related activities. The dust emitted during the above mentioned activities depend upon the type of soil being excavated and the ambient humidity levels. The dust generated during the construction activities will however, settle quickly. Therefore, the impact will be for short duration and confined locally to the construction site. The composition of dust in this kind of operation is, however, mostly inorganic and non-toxic in nature. The impact of such activities would be temporary and restricted to the construction phase. The impact will be confined within the project boundary and is expected to be negligible outside the plant boundaries. Exhaust emissions from vehicles and equipment deployed during the construction phase is also likely to result in marginal increase in the levels of SO2, NOx, SPM, CO and un-burnt hydrocarbons. Mitigation Measures Proper upkeep and maintenance of vehicles, sprinkling of water on roads and construction site, providing sufficient vegetation etc. are some of the measures that would greatly reduce the impacts during the construction phase.
4.4.2 Impact during operation Phase Being a coal based thermal power plant Suspended Particulate Matter (SPM) and Sulphur dioxide (SO2) and Oxides of Nitrogen (NOx) will be the important pollutants. Site specific meteorological parameters have been recorded by using continuous recorders. Short term 24 hourly GLC's incremental values were estimated using the site-specific meteorological data.
4.4.3
Air Pollution Modeling
Prediction of impacts on air environment has been carried out employing mathematical model based on a steady state Gaussian plume dispersion model designed for multiple point sources for short term. In the present case, Industrial Source Complex [ISC3] 1993 dispersion model based on steady state Gaussian plume dispersion, designed for multiple point sources for short term and developed by United States Environmental Protection Agency [USEPA] has been used for simulations from point sources. 4.4.3.1 Pollutants The model simulations deal with three major pollutants viz., Sulphur Dioxide (SO2), Oxides of Nitrogen (NOx) and Suspended Particulate Matter (SPM)
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 7 of 25
4.4.3.2 Model Options Used For Computations The options used for short-term computations are: The plume rise is estimated by Briggs formulae, but the final rise is always limited to that of the mixing layer; Stack tip down-wash is not considered; Buoyancy Induced Dispersion is used to describe the increase in plume dispersion during the ascension phase; Calms processing routine is used by default; Wind profile exponents is used by default, 'Irwin'; Flat terrain is used for computations; It is assumed that the pollutants do not undergo any physico-chemical transformation and that there is no pollutant removal by dry deposition; Washout by rain is not considered; Cartesian co-ordinate system has been used for computations; and 4.4.4
Model Input Data
For the modelling purpose three pollutants namely, Sulphur dioxide, Oxides of Nitrogen and Suspended Particulate Matter are considered. The details of stack emissions and the estimated emission rates are given in Table-4.1. TABLE-4.1 : DETAILS OF STACK EMISSIONS
Parameters Stack Height Number of stacks Flue diameter Flue gas velocity Flue gas temperature Volumetric flow rate Rate of coal combustion Sulphur in coal (maximum) Estimated Emission Rates Sulphur dioxide NOx @ 260 g/GJoule SPM @ 50 mg/Nm3
Units M No M m/sec o K Nm3/sec/unit Tones/hr/unit %wt/wt g/sec/unit g/sec/unit g/sec/unit
Value 275.00 1.00 8.15 22.00 398.00 843.00 619.00 0.3 1032.00 687.73 46.24
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW) 4.4.5
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 8 of 25
Meteorological Data Data recorded at the continuous weather monitoring station on wind speed, direction, and temperature at one hour interval for twelve months was used as meteorological input. Model simulations have been carried for Annual basis. •
Stability Classification The percentage occurrence of stability class for used for the model is given in Table 4.2. TABLE 4.2 : STABILITY CLASSIFICATION Stability Class A B C D E F
•
Frequency of Occurrence 7.84 3.69 4.04 47.14 14.02 23.26
Mixing Height As site specific mixing heights were not available, mixing heights based on CPCB publication, “SPATIAL DISTRIBUTION OF HOURLY MIXING DEPTH OVER INDIAN REGION”, PROBES/88/2002-03 has been considered for Industrial Source Complex model to establish the worst case scenario. The mixing heights considered for modelling are given in Table 4.3.
TABLE 4.3 : MIXING HEIGHTS Hour of the day 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
Mixing Height (mts) Pre Monsoon Post Monsoon 100 100 45 100 100 150 200 250 400 450 800 400 1000 1000 1200 1000 1200 1000 1200 1000 1000 850 800 750 500 500 500
Winter
100 200 400 500 600 700 800 800 800 600 600 400 400
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW) 4.4.6
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 9 of 25
Presentation of Results In the present case model simulations have been carried using the hourly Triple Joint Frequency data. Short-term simulations were carried to estimate concentrations at the receptors to obtain an optimum description of variations in concentrations over the site in 20-km radius covering 16 directions. The incremental concentrations are estimated for the monitoring period due to operation of the project. Resultant Concentrations after Implementation of the Project The maximum incremental GLCs due to the proposed project for SPM, SO2 and NOx are superimposed on the 98% of baseline SPM, SO2 and NOx concentrations recorded at the monitoring locations during the field monitoring period. The cumulative concentrations (baseline + incremental) after implementation of the project are tabulated in Table- 4. 4. The Annual distribution of pollution in the area, i.e., Annual isopleths for SO2,NOX and SPM are shown in Figures 4.1, 4.2 and 4.3, respectively. The maximum GLCs for SPM, SO2 and NOx after implementation of the proposed project are likely to be within the prescribed standards for industrial areas.
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 10 of 25
Figure 4.1: Isopleths- SO2
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 11 of 25
Figure 4.2: Isopleths-NOx
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 12 of 25
Figure 4.3: Isopleths-SPM
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 13 of 25
TABLE 4.4 : CUMULATIVE RESULTANT CONCENTRATIONS AFTER IMPLEMENTATION OF THE PROJECT (on 24 Hourly basis in µg/m3) Location DISTANCE/ DIRECTION
AQ1 4.2 /NE AQ2 5.6/E AQ3 3.8/NW AQ4 4.1/S Area-Max 2.25/SW
Incremental Ground Level Concentration Based on Meteorological Data Collected in 2011 NOx PM10 SO2
98 %le of Monitored Values During 2011
SO2
NOx
PM10
Resultant Concentration After Operation of Project (2x800 MW) SO2
NOx
PM10
10.49
6.96
0.47
12.61
15.49
59.65
23.1
22.45
60.12
23.66
5.77
1.06
11.64
16.53
59.34
35.3
22.30
60.40
0.01
0
0
13.18
17.82
56.5
13.19
17.82
56.50
4.92
3.28
0.22
12.11
15.54
58.32
17.03
18.82
58.54
49.65
33.08
2.22
13.18
17.82
59.57
62.83
50.9
61.79
Proposed Mitigation Measures
The various measures proposed to minimize air pollution from the power project are as follows: o
Electrostatic Precipitators with appropriate efficiency will be installed to limit the particulate (SPM) emission within statutory limit.
o
To facilitate wider dispersion of pollutants, 275 mts- high stacks
o
The NOx emissions from the boilers will be controlled by controlling combustion measures, which will be approached by way of low NOx burners or by air staging in furnace.
o
Fugitive dust will be controlled by adopting dust extraction and dust suppression measures and development of green belt along the periphery of the proposed power plant.
4.5
WATER QUALITY
will be provided.
4.5.1 During Construction Phase Effluents from the construction area mainly contain suspended solids while the sanitary waste from the labour colonies contains suspended as well as organic matter. The loose construction material like sand, cement etc. and excavated earth/construction debris may get washed off during heavy precipitation and finally reach the IB River. This may increase the suspended solid of the receiving water body. 4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 14 of 25
Adequate arrangements for proper drainage and disposal of wastewater and routing of the effluents from construction area through sedimentation basins and provision of proper sanitary facilities with treatment will eliminate these problems of water pollution. Moreover, these impacts will be temporary in nature. 4.5.2
During Operation Phase
The impacts of a coal based thermal power project during operation phase could result from several activities such as discharge of hot cooling water, discharge of main plant effluents and sanitary effluents and discharge of ash pond overflow. Following water pollution control measures are proposed to minimise the impacts: •
The project will have a closed cycle cooling system with cooling towers, hence there will be no thermal pollution of the receiving water body.
•
Fly ash disposal system will be based on high concentration slurry disposal system while bottom ash disposal system will be based on wet slurry disposal with ash water recirculation. Therefore, there will be no discharge of overflow from ash disposal area.
•
Each of the effluent stream emanating from the project shall be individually treated and then routed through a Central Monitoring Basin (CMB), which will also act as an equalisation chamber. Only treated effluents, conforming to regulatory standards shall be discharged.
•
The sanitary effluents from the main plant and township areas shall be treated in a Sewage Treatment Plant (STP) and the treated effluent from STP conforming to regulatory standards shall be discharged.
•
All the effluents shall be treated and recycled/ reused to the maximum possible extent and only a minimum quantity of effluents shall be discharged (33 m3/hr with ash water recirculation system).
4.5.3 Impacts on Ground Water Quality during Operation Phase NTPC has conducted several geo-hydrological studies of the ash disposal areas at its projects (Singrauli, Rihand, Vindhyachal, Korba, Farakka and Talcher) through reputed institutions like Indian Institutes of Technology, Roorkee and Mumbai, Centre for Studies on Man and Environment, Calcutta. All these studies conclude that the leaching of heavy metals from ash occurs only under pH 4 or below. In practice, the pH of the ash water is either neutral or alkaline (7 or above) and hence the leaching of heavy metals is highly unlikely. The contamination of ground water due to leachate from ash disposal area is a major area of concern. Preliminary geotechnical investigations of the ash disposal area reveal that the entire ash disposal area is covered by 2-5 m thick stiff sandy clay with clay content varying from 48 to 59%. The permeability of this clay layer is of the order of 7.56x10-10 to 1.34x10-9 m/sec. The clay layer is overlaid on a coarse sand layer, 1.5 to 8 meters thick. Soft rock is encountered at a depth of 5 to 20 meters while very dense hard rock exists at a depth of 7 to 19 meters. Both, the clay and the rock layers will act as a natural liner and prevent downward percolation of leachates, if any, from contaminating the ground water. The hard rock has a very low porosity, of the order of 2.63-2.73% and low permeability, of the order of 7.03x10-5 to 1.34x10-4 m/sec. 4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 15 of 25
Both, the clay and the rock layers will act as a natural liner and prevent downward percolation of leachates, if any, from contaminating the ground water. 4.6 4.6.1
NOISE During Construction Phase
The operation of construction equipments will lead to increase in background noise levels in the area. The major sources of noise are vehicular traffic, construction equipment’s like dozers, scrapers, concrete mixers, cranes, generators, pumps, compressors, rock drills, pneumatic tools, saws, vibrators etc. The noise levels expected due to operation of these equipment’s range between 70-90 dB (A). Typical noise levels of construction equipment are given in the Table – 4.6.1
TABLE – 4.6.1 TYPICAL NOISE LEVELS OF CONSTRUCTION EQUIPMENT Equipment Category Earth movers
Equipments Front loaders Backhoes Tractors Scrapers, graders Pavers Trucks
Noise Level dB(A) 72 to 84 72 to 93 76 to 96 80 to 93 86 to 88 82 to 94
Concrete mixers Concrete pumps Cranes (movable) Cranes (derrick)
75 to 80 81 to 88 75 to 86 86 to 88
Pumps Generators Compressors
70-75 71 to 82 74 to 86
Pneumatic wrenches
83 to 88
Material handlers
Stationary equipment
Impact based equipment
The predicted noise level at 0.5 km during the construction phase will be of the order of 42 dB (A). However, the ambient noise level recorded during the field studies in the nearby Darlipali village located at a distance of 0.5 km from the power plant ranges from 45.7 to 54.3 dB(A) and Leq is 57.5 dB(A). As the ambient noise levels are higher than the predicted noise levels, due to masking effect no increase in ambient noise levels during construction phase is envisaged. The impact of generated noise on the environment is likely to be insignificant reversible and confined within the plant boundary.
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
4.6.2
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 16 of 25
•
Mitigation Measures
i.
Equipments with lower noise generation levels to be used.
ii.
Noise and emission reducing barrier shall be erected during construction stage along the boundary of the proposed plant which will obstruct or dissipate sound emission and surrounding area will not get disturbed
iii.
Use of exhaust silencers and noise suppressors /mufflers in heavy equipments & keeping vehicles in good condition
During Operation Phase During operation phase, the main noise generating sources are Turbine, Boiler Feed Pumps, Air Compressors, Cooling Towers, C.W Pumps Forced Draft Fan, Coal Handling Plant, and Primary Air Fan and Coal Mills. In addition, intermittent noise is also generated due to operation of diesel generator. Any industrial complex in general consists of several sources of noise in clusters or single. This clusters/ single source may be housed in buildings of different dimensions made of different materials or installed in open or under sheds. The material of construction implies different attenuation co-efficient. For computing the noise levels at various distances with respect to the plant site, noise levels are predicted using a user friendly model the details of which are elaborated below. 4.6.2.1 Mathematical Model for Sound wave propagation during Operation For an approximate estimation of dispersion of noise in the ambient air from the source point, a standard mathematical model for sound wave propagation is used. The noise generated by sources decrease with increasing distance from the source due to wave divergence. An additional decrease in sound pressure level with distance from the source is expected due to atmospheric effect or its interaction with objects in the transmission path. For hemispherical sound wave propagation through homogenous loss free medium, one can estimate noise levels at various locations, due to different sources using model based on first principles, as per the following equation: Lp2 = Lpi - 20Log(r2 / rl) - AE – AM
(1 )
Where, Sound Lp2 and Lp1 are the Sound Pressure Levels (SPL) at points located at a distances of r2 and r1 from the source: AE & AM are attenuations due to Environmental conditions (E) and Machine correction (M). The combined effect of all the sourCBS can be determined at various locations by the following equation. Lp(total) = 1 0 Log ( 10 (Lpa /10) + 10 (Lpb /10) + 10 (Lpc /10)
(2)
Where, Lpa, Lpb, Lpc are noise pressure levels at a point due to different sources. Machine Correction (AM)
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 17 of 25
The background noise level, when the machine is not in operation should be determined at one or more locations while conducting the test. The readings at each location, with the machine in operation should exceed the background levels by at least 10 dB in each pressure level of interest. If the difference is less than 10 dB, correction should be applied. If the difference between the measured sound and the background sound in any sound pressure level is less than 3 dB a valid measurement of the machine cannot be made. In order to reduce background noise to acceptable levels, it may be necessary to acoustically treat various equipment. Environmental Correction (AE) The equivalent sound pressure level can be calculated from the measured sound pressure level (Leq measured) averaged over the measurement surface area'S' and from corrections K1 and K2 and is given by; Leq(Calculated) = Leq(measured) - K 1 - K 2 (3) Where, K1 = Factor for the background noise correction. The correction was , not applied in this modeling exercise, as it was not possible to measure the background noise levels by putting off machines. Hence it was considered as zero. K2 = Environmental correction 4.6.2.2 Input for the Model The designed noise level for the various equipment generally used for thermal power plant of 800 MW are given in Table 4.6.2. The values mentioned are at 1 m distance from the source. Table 4.6.2: Likely Noise Levels in Darlipali STPP Sr. No. 1 2 3 4 5 6 7 8 9 10.
Source Name Turbine Diesel Generator* Cooling Water Pump Boiler feed Pump FD Fan ID Fan PA Fan Coal Mill Coolinq Tower Coal Handlinq Plant
(Unit-I and II ) Noise Level in dB(A) 90 75 90 90 90 90 90 90 85 90
Note: * After acoustic enclosure 4.6.2.3 Results of the Model The ambient noise levels have been predicted at the boundary of the plant. The nearest residential area is at a distance of 0.5 km (500 m) from the power plant. The ambient noise level measured at the Darlipali village is varying between from 45.7-54.3 dB(A) and Leq is 4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 18 of 25
57.5 dB(A). The noise level predicted at the same distance from the power plant is 42 dB(A)m as given in Table 4.6.3. As the ambient noise level is higher than the predicted noise levels due to masking effect, no increase in the ambient noise level during operation phase is envisaged. Table 4.6.3: Predicted Noise Level Sr. No. Distance in meters 1 100 2 200 3 300 4 400 5 500 6 750 7 1000 8 1500 9 2000 10 2500
Noise level in dB(A) 75.0 65.0 55.0 48.0 42.0 39.0 37.0 35.0 32.0 29.0
4.6.2.4 Industrial Noise Standards: In the operation area where it would not be feasible to keep ambient noise levels below 85 dB(A), operating personnel are provided with ear plugs and ear muffs. Except at turbine and boiler feed pump area, the noise levels are below 90 dB(A) limit. Most of the executives will be working in control room provided for gas turbine and steam turbine. As per Occupational Safety and Health Administration (OSHA) Standards, the maximum allowable noise level for the workers is 90 dB(A) for 8 hours exposure a day as given in Table 4.6.4. Therefore, adequate protective measures in the form of ear muffs/ ear plugs to the workers working in high noise areas should be provided during operation. In addition, reduction in noise levels in the high noise machinery area will be achieved by adoption of suitable preventive measures such as suitable building layout in which the equipment are to be located, adding sound barriers, use of enclosures with suitable absorption material, etc. Further, in addition to the plant noise control measures, all the open areas within the plant premises and all along the plant boundary will be provided with adequate green belt to diffuse the noise. TABLE - 4.6.4 PERMISSIBLE EXPOSURE NOISE LIMIT Total time of exposure per day in hours 8 6 4 3 2 1 112 ¼
Sound pressure level in dB(A) 90 92 95 97 100 105 110 115
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 19 of 25
•
Mitigation Measures
i.
Sound proof room for turbine hall
ii.
Compulsory use of personnel protective equipment (PPE) such as ear plugs for the workers
iii.
Installation of noise generating machinery, strictly in compliance with the recommendations of the manufacturers. This would ensure an installation free from vibration and exhaust leaks which are also major contributors to increased noise levels
iv.
Use of damping materials such as thin rubber sheet for wrapping the worn places of compressors, generators etc.
v.
Shock absorbing techniques to reduce impact
vi.
Use of physical barriers and green belt development around the plant to restrict the noise from going outside the proposed plant boundary during operation
4.7
TERRESTERIAL ECOLOGY
4.7.1
Impact during construction phase
The initial construction works at the project site involving land clearance, cutting, filling and levelling will cause loss of potential agricultural productive land and loss of vegetation to some extent. The removal of herbaceous vegetation from the soil and loosening of the top soil generally causes fugitive emission. Deposition fugitive dust on pubescent leaves of nearby vegetation may lead to temporary reduction of photosynthesis. Such impacts would, however, be confined mostly to the initial periods of the construction phase and would be minimized through adoption of control measures such as paving and surface treatment, water sprinkling and plantation schemes. The impact would be restricted within the plant boundary. Thus, the impacts of construction activities will be marginal in scale. The increase in vehicular traffic due to construction coupled with higher noise level due to various constructional activities may drive away the local fauna from project site to neighbouring area. However project site/area does not harbour fauna of significant importance. Hence, the impact on fauna is expected to be minimal.
4.7.2
Impact during operation phase
Combustion of coal produces gaseous and particulate pollutants which remain in air, soil and water and their reactions in atmosphere produces other derivatives. Pollutants affect the normal growth of biota ranging from plankton to higher forms of life. The gaseous pollutants like SO2 and NOx, at a very low dose act as atmospheric fertiliser for the vegetation. However at higher doses, they are injurious to both vegetation as well as animals. The effects on plants range from loss of productivity, chlorosis of leaf tissue to necrosis of leaf tissue and suppressed growth of sensitive species at higher doses. However since the predicted ambient
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 20 of 25
ground level concentrate of pollutants are within the prescribed AAQ standard the impact during operation would be minimal. Coal dust particles from coal stock yard are injurious to vegetation. The plant exposed to coal dust shows brown necrotic lesions on the leaves, starting at the tip and progressing down the lamina. Fly ash particles affects vegetation including changes in the cuticular pattern of leaves, decrease in the number and size of stomata, clogging of stomata leading to physiological changes. However, low levels of fly ash in the soil improve the soil condition. Fugitive dust emission from CHP and ash disposal area will be controlled through dust suppression and dust extraction facilities to minimise these impacts. •
4.8
Mitigation Measures •
Effective management of ash pond area to ensure a blanket of water will significantly reduce fugitive emissions and hence minimal impact is expected on surrounding flora and fauna due to deposition of fly ash.
•
The leaf surface acts as reaction centres for removing atmospheric pollutants. So the plant having leaves of large surface areas are suggested for development of green belt.
•
Extensive plantation of pollutant resistant trees in and around the project area will serve as pollution sink and noise barrier.
•
All the air pollution control measures should be installed and operated efficiently. AQUATIC ECOLOGY
4.8.1 Impact during Construction Phase The surface run off arising from the construction activities of proposed plant may increase the suspended solids in the surrounding water bodies and also these may impact the aquatic ecosystem of the study area particularly natural Basundara nalla/drain in the vicinity of proposed project site. 4.8.2 Impact during Operation Phase The treated effluents conforming to regulatory standards shall be discharged into natural drains. However, as the quantity is small and the effluents shall be fully treated, the water quality of the receiving water body may not change significantly. Therefore, no significant impact on the aquatic eco-system is expected. Further, Basundhara nalla does not have any important/significant aquatic life •
Mitigation Measures i.
The surface run off originating from various construction activities should be collected and treated.
ii.
Sanitation facility should be provided to construction labourers at the site.
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
4.9
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 21 of 25
iii.
Efficient effluent treatment and recycling and reuse of waste waters to the maximum extent possible to minimise the impact on aquatic fauna should be adopted.
iv.
Closed cycle cooling system to avoid hot water discharge for the protection of aquatic life.
SOCIO ECONOMIC ASPECTS The impacts on demography and socio-economic status of the area due to construction and operation will be positive as well as negative in nature. These impacts may be broadly classified into two groups. • • • •
4.9.1
Direct impact due to acquisition of land Change in socio-economic scenario of the area Increased stress on public utilities and resources of the area and Indirect impacts due to Immigration of work force
Rehabilitation and Resettlement (R&R) of Project affected Persons As regards formulation of R& R plan, a Rehabilitation and Periphery Development Advisory Committee (RPDAC) for Darlipalli has already been constituted by the Govt. of Odisha as per State practice. Its first meeting was held on 17.11.2011. Socio Economic Survey is under progress by XIM Bhubaneswar, the SES will be completed within 4 months. It is expected that R& R plan will be finalized within 6 months in consultation with the stakeholders through RPDAC. The R& R plan will not only cover individual R& R benefits in line with the extant R& R policy but also community development activities in the project affected and neighboring area covering/ encompassing works related to infrastructure, health, education, sanitation, welfare and capacity building etc. as per need and requirement.
For setting up Darlipalli STPP, the land is proposed to be acquired from two villages Darlipalli and Raidihi. Majority of land (about 94%) belongs to village Darlipalli and the rest belongs to village Raidihi. Further, the major part of land proposed to be acquired (77.4%) is provate land while rest is govt. land (20.5%) and small area of forest land (2.1%). A detailed socio-economic survey for project affected persons (PAPs) in Darlipalli has been completed and as per results of the survey, there are about 627 PAPs and 250 Homestead Oustees. The profile of PAPs and HSOs for Darlipalli village as per SE Survey is as follows:
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 22 of 25
S. No. 1 2 3 4 B 1 2 3 4
Description PAP HSOs Schedule Caste 12.1% 4.8% Schedule Tribe 25.2% 69.6 Other Backward Caste 59.2% 25.2% General 3.5% 0.4% Literacy Illiterate 20.9% 31.2% Up to 5th pass 27.4% 27.2% From 6th & Upto 10th class 27.7% 34.8% From 11th to Graduation 24.0% 6.8% Total 100% 100% The survey for Raidihi villahe, which accounts for about 6% of project land is in progress. However, the actual no of PAPs/ HSOs would be available only after disbursement of land compensation. 4.9.2
R&R Plan R&R plan for PAPs and HSOs would be formulated in consultation with stake holders thru ‘ Rehabilitation and Periphery Development Advisory Committee (RPDAC) as per provisions outlined in Odisha R&R policy-2006 and revision of cash package notified vide letter dated 21.08.08. The rehabilitation benefits proposed to be provided are as follows: Category
Amount (Rs In lac)
Rehabilitation Grant in cash in lieu of employment) as per provisions outlined in odisha R&R policy-2006 Displaced family losing all land including homestead Displaced Family losing more than 2/3rd of agricultural land and homestead land Displaced family losing more than 1/3rd of agricultural land and homestead land Displaced family losing only homestead land but not agricultural land Displaced family losing only agricultural land but not homestead land
5.52 3.31 2.21 1.11 1.11
Proposed resettlement benefits for HSOs, as per provisions of Odisha R&R policy2006 are as follows: Description House site in R&R colony Assistance for self relocation Home building assistance Assistance for temporary Shed Transportation charges Subsistence allowance
Amount/ Details 1/10 th Acre of land Rs. 0.56 lac Constructed house Or Rs. 1.66 lac Rs. 0.111 lac Rs. 0.023 lac Rs. 2300/- per month for 1st year
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 23 of 25
Apart from various R&R Benefits listed above, the PAPs and other local persons shall be benefitted in a number of ways, as follows: EMPLOYMENT OPPORTUNITIES • All unskilled jobs will be generally reserved for PAPs and preference will be given to PAPs for skilled jobs subject to availability and suitability of the PAP. • Jobs with contracting agencies and preference for award of petty contract to registered co-operative societies of PAPs. • Facilitation of training programme for capacity building • Petty contracts to PAPs. • Allotment of shops/ Kiosks in NTPC township. • Hiring of vehicles • Allotment of works to PAPs for tree plantation, horticulture and housekeeping. • Women empowerment to various capacity building programme OTHER DIRECT BENEFITS • Alternate employment opportunities to PAPs • Health facilities • Subsidized medical facility in NTPC hospital • Medical camps. • Opportunities to local contractors to enhance their businesses. • Fee reimbursement and scholarship to PAPs taking admission in Govt. ITI. • The wards of PAPs will also be charged fees at par with NTPC employees children in NTPC township schools • Facilitating the augmentation of infrastructure for supplying of electricity in 5 KM area around Darlipalli Power Project, in association with State Govt in line with approved scheme of Govt. of India • Drinking Water, Health facilities, Schools, Roads, Sanitation etc as per need and requirement. • Community Development in project affected villages. OTHER INDIRECT BENEFITS • Infrastructural development i.e improvement in roads, electricity, supply of drinking water , sanitation , educational institutions and transportation facilities. • Scholarships to students and facilitation for sports. • Training for self employment (computer, stitching, embroidery etc) • Training / financing facilitation for development of rural small scale industries i.e bee keeping, poultry, dairy farming etc 4.9.3
CSR and Community Development Plan A comprehensive community Development Plan would be formulated in consultation with stakeholders thru RPDAC including the following activities:
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 24 of 25
HEALTH: • • •
Mobile clinic in ambulance with testing and diagnostic facilities. Upgradation of local PHC with equipments and infrastructure. Health camps in affected villages.
EDUCATION: • • •
Augmentation of infrastructure and equipments, furniture, in villages schools. Scholarships to meritorious students. Partnerships in state sponsored education programmes.
WATER: • •
Provision of potable drinking water supply in affected villages Awareness campaigns for water borne diseases, sanitation and hygiene.
INFRASTRUCTURE: •
Construction of roads, drainage, community halls, school buildings, health centers, public utilities, sanitation facilities
CAPACITY BUILDING: • • •
Setting up new ITI/ Adoption of ITI with necessary infrastructure and machinery. Sponsorship of PAPs/ wards for full term courses/ Short term courses, vocational training Specific Programmes for ladies.
VULNERABLE PERSONS: • •
Pension to vulnerable (Elderly/ widows/ Special Abilities) Creation/ Adoption of Old Age Homes etc.
SPORTS AND CULTURE: • 4.9.4
Regular Rural Sports, Facilitation/ Sponsorship to local talent etc
Impacts Due to Immigration of Construction Workforce
The immigration of work force for construction phase (including contractor labours) would have marginal impact on demography (e.g. changes in total population, sex ratio, literacy level, main workers etc.) of the immediate vicinity area. In addition, the socio-economic status of the area may also get affected due to flow of men, material and money. The positive impacts are following:
Increase in employment opportunity to non-workers in the study area as non-skilled and semi-skilled workers to the contractors / sub-contractors.
Growth of services and increase in employment and trade opportunities in service sector.
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
Comprehensive Environmental Impact Assessment report For Darlipali Super Thermal Power Project (2x800 MW)
Doc. No.: 9549/999/GEG/S/001 Rev. No.: 2 Issue Date: 27.11.2011 Page 25 of 25
Influx of persons with higher spending power and different socio-cultural background will improve the socio-cultural environment of the area, though occasional tension as a result of this influx cannot be totally ruled out.
Increase in per capita income and overall economic upliftment of the area and improvement in transport, communication, health and educational services.
The negative impacts could be summarised as : •
Strain on civic amenities (like road, transport, communication, water supply and sanitation, power supply, health care, education and recreational utilities etc.) due to increase in floating population.
•
Further urbanization of the area leading to appreciation of land cost and house rents, increase in labour rate.
•
Increase in consumer prices of indigenous services and produces like egg, fish, vegetables, milk, etc.
•
Interference with the rural life of neighbouring villages and social conflicts be between the guest and host communities.
•
Loss of open space and visual impairment to the residents in the contiguous areas.
It is difficult to assess the above impacts quantitatively on a measurable scale. However, most of these impacts will be short term and limited to the construction period only. While increase in employment opportunities (project and service sector) and over all economic upliftment of the area is certain to happen, the negative impacts would be limited to construction phase. The infrastructural facilities shall be augmented / strengthened during construction of the project, if necessary. Majority of the people living in this area are involved in agricultural and auxiliary activities. The tribal people depend on forests and other natural resources for their livelihood and sustenance perspective but also with livelihood perspective. Many a times, these indigenous tribal populations remain marginalised. This is a major developmental challenge both in terms of economic growth and, more importantly, socio-cultural perspective.
4.0 Anticipated Environmental Impacts and Mitigation Measures Kirloskar Consultants Limited Pune
