31-08-2012, 10:15 AM
The TATA Power Company Ltd 1000 MW Coal Based Thermal Power Plant
Tata power plant analysis.doc (Size: 46 KB / Downloads: 50)
Background of the report
The Tata Power Company Ltd. is planning to set up a thermal power plant at Naraj Marthapur, Cuttack, located in Orissa.
This report is a technical evaluation of the Environment Impact Assessment (EIA) document submitted by Tata Power Company Ltd as part of the clearance process for a 1000 MW coal based thermal power plant. The EIA has been conducted by the Gurgaon -based SGS India Private Limited. The study area for the EIA study is 10-km radius.
About CSE
Centre for Science and Environment (CSE) is an independent, public interest research and advocacy organisation, which aims to increase public awareness on science, technology, environment and development. The Centre was started in 1980.
For more than two decades, CSE has been creating awareness about the environmental challenges facing our nation. It has been:
• Searching for solutions that people and communities can implement themselves,
• Challenging the country to confront its problems,
• Inspiring it to take action and,
• Pushing the government to create frameworks for people and communities to act on their own.
About the project
The Tata Power Company Ltd. proposes to set up a coal based thermal power plant of 1000 MW having configuration of 2x125 MW + 2x125 MW + 2x250 MW. The area to be acquired for the siting of the project is around 400 Ha. EIA states that out of the total power generation, 350 MW will be supplied to steel plant at Kalinganagar, around 250 MW will be given to GRIDCO and remaining will be sold on mrechant basis. The estimated cost of the project is Rs 49000 crores.
According to the EIA, project will consume 6 MTPA of coal (indian coal) and 96,684 m3 of water per day. The proposed plant will sourced water from the Mahanadi, which flows west to east on the northern side of the site. The EIA states that water will be drawn from Mahanadi at about 3 km from the proposed plant site (pp15, chapter 2) but fails to provide intake point location.
There is large variation in flow from monsoon to non-monsson period in the Mahanadi river, as per the estimation, percentage reduction in flow from monsoon to non-monsoon is around 86%, considering monsoon flow at the upstream of the Naraj barrage is 46474 cusec (113721878 m3/day) and non-monsoon flow is 6292 cusec (15396524 m3/day). Inspite of large variation in flows, river is extensively used for irrigation, city water supply and industrial requirement.
Monitoring impact of air pollution: The EIA has been conducted during the summer season. However, for proper evaluation of air pollution impacts, monitoring and data collection should be done during winter also. Therefore, given the sensitive nature of the project site, a rapid EIA with one-season data collection is insufficient.
Impact of the project on local air quality
Coal based thermal power project ranks top in air pollution, water consumption and in generation of solid wastes. Assessing the impact of air pollutants is therefore very important in the EIA for a thermal power plant. Suspended particulates, sulphur dioxide (SO2), oxides of nitrogen (NOx), carbon dioxide (CO2) and emissions of mercury have to be estimated, and their impact assessed.
Particulate emissions: The EIA for the proposed project has mentioned that particulate emission from stacks after ESP is 100 mg/Nm3 (see pp29, chapter 2, table 2.6), which works out to 1972 tonnes of particulate emissions per annum (calculated based on gas flow rate and diameter of the stacks).
SO2 and NOx emissions: The EIA has estimated the SO2 emissions as approximately 164 tpd (see pp 28, chapter 2). This estimation has been crosschecked and verified by CSE, by using information provided on coal consumption, and sulphur content in coal. However, while the EIA mentions that LDO & HFO will be used as a secondary fuel, there is no mention of how much oil would be consumed. Oil has a high sulphur content (1.8 to 2.5%). If we consider from LDO & HFO, SO2 emission would be around 166 tpd. On annual basis, LDO & HFO will add 847 tonnes of SO2, which has not accounted in the calculation in the EIA. On annual basis, both coal and fuel oil will add 60,590 tonnes of sulphur dioxide in the atmosphere. Being an ecologically sensitive area and close to sanchuary and National park, no point source mitigation measures has been suggested. Studies show that SO2 emissions even at low concentrations of 5-20 g/Nm3 can be detrimental to some kinds of plants – for instance chickoo, litchi, cashew, mangoes etc. They can cause decrease in the yields, chlorophyll loss and greater leaf fall. The impact of SO2 emissions is even higher under humid and high wind conditions.
Similarly no point source mitigation measures has suggested for NOX emission as power plant will add 18,186 tonnes of NOX per year to the ambient air (see pp 29, chapter 2, table 2.6). NOx emissions can be detrimental at low concentrations of 3-20 ppm. The report has not suggested any mitigative measures.
Mercury emissions: Mercury emissions from the power plant have been completely overlooked by the EIA. There is no mention whatsoever – no estimation, no impact analysis, no mitigation. However, this should not be ignored, as thermal power plants account for 70 per cent of the country’s mercury emissions. Considering average mercury content of 0.25 ppm, mercury emissions from the proposed plant account for 1494 kg/annum.
Carbon dioxide emissions: The EIA has also completely ignored CO2 emissions from the proposed plant. This is not acceptable, as the thermal power sector contributes 11 per cent of total CO2 emissions , 65 per cent of the industrial greenhouse gas emissions . The proposed plant will release 6 million tonnes of carbon dioxide per annum (calculated at the rate of 997 gms of CO2/kWh of power generated).
EIA has monitored the air quality of the study area and concluded that all the paramaters (SPM,RSPM, SOX and NOX) are well withien the standards. But table 3.6 summary of ambient air quality monitoring results, clearly indicate high level of RSPM at Mundali (project site), Narag (1.5 km from project site), Ramdasnagar (2 km), Bidyadharpur (4 km) and all these locations have RSPM level is around 70 microgram/Nm3 against standard of 100 microgram/Nm3. If this is the scenario, then once the plant starts its operation, the RSPM will increase as all these sites are close to project and under the influece of probable wind direction. However, EIA fail to comment on this issues and concluded that background level is well within the standard.