4.0 RESEARCH STUDY INTO AIR POLLUTION

4.1 Atmospheric Transport of Air Pollution

In the field of atmospheric transport of air pollution, not much work has been done. National Physical Laboratory (NPL) is proposing to study the atmospheric transport of air pollution using data from American, Upper Atmospheric Research Satellite (UARS). Internally lot of work has been done to estimate the pollution concentration using various models. India Meteorological Department (IMD) and NPL are engaged in studying the meteorological aspects related to transport of air pollutants. The list of few experts working in this area have been described in the format enclosed at Attachment - II.
    1. National Air Quality Criteria and Standards
To provide legislative support for prevention and control of air pollution, the Govt. of India enacted a central legislation called the Air (Prevention & Control of Pollution) Act, 1981 referred to as Air Act, 1981. The Act aims at prevention, control and abatement of pollution. The Govt. of India has also passed a comprehensive Act for the Environment (Protection) Act, 1986 which covers various aspects of environment including air pollution. One of the mandate of Central Pollution Control Board under the Air Act, 1981 is to lay down standards for the Quality of Air and Emission Quantities. The State Pollution Control Boards may lay down suitable conditions while granting permission to discharge air pollutants (called consent) in the light of emission standards, developed by the Central Pollution Control Board and subsequently notified through the rules framed under the Environment (Protection) Act, 1986 rules.

The primary aim of the ambient air quality standard is to provide a basis for protection of public health from adverse effect of air pollution and for eliminating or reducing to a minimum those contaminant of air that are known or likely to be hazardous to human health and well being. The air quality standards normally should report the concentration of chemical compounds in air that would not pose any health hazard to the human population. However, the realistic assessment of human health hazard necessitates a distinction between absolute safety and acceptable risk. To aim at achieving absolute safety one would need a detailed knowledge of lose response relationship in individuals in relation to all sources of exposure, the types of toxic effect, elicited by specific pollutants or their mixture and the existing health status of human population. However, such comprehensive

and conclusive data on environmental contaminates are not always possible, certainly not for all types of pollutants. Very often the relevant data are
scarce and the quantitative relationship uncertain. Central Pollution Control Board consulted experts in the field of air quality and health effects of air pollutants to formulate the air quality standards. Subsequent to the deliberation of experts and consensus reached CPCB as formulated

the ambient air quality standard for most commonly found air pollutants. Different standards have been laid down for industrial, residential and sensitive areas to protect human health and our national resources from the effects of air pollution. The notified Ambient Air Quality Standards are presented in Table 4.1
 

 4.3 Impact of Air Pollution Air Pollution can damage the environment including vegetation, crops and forests. Much work has been done to study the impact of air pollution on the environment including human health, livestock, corrosion of materials, building, monuments etc.. Some cases of impacts that have been suspected of being linked with air pollution are described in this chapter.

Case - I

We are all aware of intriguing national debate on the "Effect of Pollution on the Taj at Agra". The Taj Mahal, one of the finest garden tombs in the world, stands on the bank of the river Yamuna and it was built by the Mughal Emperor, Shahzahan to enshrine the mortal remains of his Empress, Mumtaj Mahal. The construction of the tomb began in 1631 A.D. and it was completed in 1643 AD.

In the year, 1973-74 when the Govt. of India decided to erect refinery at Mathura, apprehensions were made with regard to possible sadverse effects as a result of gaseous pollution due to emission on Taj and other monument in and around Agra. Prior to 1972, no proper study was made to evaluate the impact of the environment on Taj. Beside this, between 1942 and 1972 and also later on Archaeological Survey of India had made some studies on the building material, used in Taj Mahal. This included :
 
 
    1. Study of Marble and sand stone and examination of weathered red sand stone on the lining of the interior of the dome;
    2. Environmental parameters, temperature variation, moisture attack, rainfall pattern, impact of meteoric waters and humidity gradients;

      3.  

       

      Factors of deterioration, thermal damage, salt crystallisation and

      Table 4.1 National Ambient Air Quality Standards
       
      Pollutant
      Time Weighted Average
      Standards
      Unit
      Industrial Area
      Residential, Rural and other Areas
      Sensitive area
      Sulphur dioxide (SO2) Annual Average*
      80
      60
      15
      µg/m3
      24 Hours Average**
      120
      80
      30
      µg/m3
      Nitrogen dioxide (NO2) Annual Average*
      80
      60
      15
      µg/m3
      24 Hours Average**
      120
      80
      30
      µg/m3
      Suspended Particulate Matter (SPM) Annual Average*
      360
      140
      70
      µg/m3
      24 Hours Average**
      500
      200
      100
      µg/m3
      Respirable Suspended Particulate Matter (RSPM) Annual Average*
      120
      60
      50
      µg/m3
      24 Hours Average**
      150
      100
      75
      µg/m3
      Lead (Pb) Annual Average*
      1
      0.75
      0.5
      µg/m3
      24 Hours Average**
      1.5
      1
      0.75
      µg/m3
      Carbon monoxide (CO) 8 Hours Average**
      5
      2
      1
      mg/m3
      1 Hour Average
      10
      4
      2
      mg/m3
      * Annual Arithmetic mean of minimum 104 measurements in a year twice a week 24 hourly at uniform interval
      ** 24 hourly/8 hourly values should be met 98% of the time in a year. However, 2% of the time, it may exceed but not on two consecutive days
      Source :
      Central Pollution Control Board, Delhi
      Note :
      1. National Ambient Air Quality Standard : The levels of air quality necessary with an adequate margin of safety, to protect the public health, vegetation and property.
      2. Whenever and whereever two consecutive values exceed the limit specified above for the respective category, it would be considered adequate reason to institute
      regular/continous monitoring and further investigations
      3. The State government/State board shall notify the sensitive and other areas in the respective states within a period of six months from he date of notification of
       

  1. growth of moss lichen and Algae.
The Govt. of India constituted an expert committee in 1974 with the purpose to guide and take suitable remedial anti pollution measures. This committee was headed by an eminent scientist, Dr. S. Varadarajan. The committee suggested various measures for improving the air quality in and around Agra. Another high powered committee was set up by Govt. in 1979 with Prof. M.G.K. Menon as Chairman and an expert group to assist the high power committee to oversee the implementation of the necessary air pollution control measures.

A joint parliamentary committee, headed by Dr. Karan Singh visited the Taj and Mathura Refinery (under construction) on October 1, 1978 to evaluate the effect of air pollutants on Taj and it reported to the Parliament on May 18, 1979 and considered Mathura Refinery, a threat to the Taj. A committee under the chairmanship of Dr. T.N. Khoshoo, the then Secretary, Department of Environment, was constituted in 1982 to monitor the pollution abatement measures. Many other committees were constituted to suggest long term and short term measures to be adopted to control such pollution which is harmful to the Taj Mahal. On the direction of the Hon'ble Supreme Court of India, dated April, 1994, an expert committee under the chairmanship of Dr. S. Varadarajan was constituted by Ministry of Environment & Forests. Some issues requiring attention of the committee include

- Survey of the Taj Trapezium Environmental Area and to make a report regarding the sources of pollution in the Taj Trapezium.
  The Indo-US workshop on Environment Assessment, held from March 7 to 10, 1994, recommended priority in Govt. funding to address the water, transport, pollution and power problems of the Agra-Mathura Heritage area as the pre-requisite to create an adequate environment for the Heritage area/site. This needs establishment of a comprehensive regional plan and an especial development strategy which may include satellite towns and growth Corridors.

Case - II

In a case of suspected industrial pollution, high mortality among cattle was reported in early months of 1991 at the border area of Maharashtra state and Union Territory of Dadra and Nagar Haveli (in the vicinity of Lead Processing Unit). Animals from the exposed area showed significantly very higher blood lead level (466.4 + 166.8) compared to that from control animals (59.2 + 23.7) selected from Dairy farm. Animals drinking water and grazing in the surrounding area of the factory could be the reason of high observation of lead.

Soil samples, collected from nearby the factory wall showed 6.4 - 36 m g/gm lead while soil samples collected from nearby village Kalandevi had only 2.2 m g/gm. Grass samples collected from the same spot from where soil samples were collected both at factory site and village showed higher lead 14.4 - 49.1 m g/gm compared to 6.8 m g/gm in grass from village. Tree leaves from varying distances from factory showed lead content of 24.3 - 54.4 m g/gm against the lead level of 0.4 m g/gm from tree leaves collected form village side.

Case - III

Another case of lead poisoning in animals were reported from village Siraspur and Nangloii Mundaka region in Delhi in 1994. It was observed that in both the areas secondary lead smelting units in small furnaces (Bhattis) within adequate pollution control measures were being operated. The investigation at Mundaka revealed that the leaf samples of five different species collected from location around the smelters showed lead concentration as high as 282 mg/kg. The lead concentration in fodder varied from 157 to 4467 mg/kg. The soil samples around the exposed area showed lead concentration between 72-2062 mg/kg against the control value of 12 mg/kg and normally observed range of 5 - 25 mg/kg (Ref. WHO). This indirectly indicates the higher level of lead in vegetation cultivated on the lead contaminated soil.

In the Siraspur region, the soil samples, collected from the surface of agriculture field showed a very high lead content from 122 mg/kg - 940 mg/kg. The high presence of lead is due to emissions from the smelters spread in this area. The leaf samples showed deposition of lead as high as 22.4 m g/cm2. The fodder and grass samples collected from different locations around the smelter had lead content deposited on the surface from 0.3 m g/cm2 to 3.9 m g/cm2, indicating its presence to some specific emissions nearby.

The domestic animals that feed on this grass and fodder are likely to suffer from adverse effect due to presence of lead. The general complaint of the villagers residing in the area nearby was that the number of buffaloes and cows who consumed the fodder from the nearby fields became blind, mad and died thereafter. In number of other cases also impacts linked with air pollution have been reported, but all such cases cannot be elaborated..
 
 

 4.4 Future Trends in Emitting Sources and Emissions The urban areas represent complex environmental problem burgeoning urban population beyond the carrying capacity of the different components of
the urban ecosystem coupled with indifferent urban governance are the root cause for urban environmental problems.

In the power sector, thermal power which constitutes bulk of the installed capacity for electricity generation is an important source of air pollution. Small Scale Industries, specially foundries, chemical manufacturing and brick making are also significant polluters. Various environmental pollution control measures adopted by Government of India are listed below:-

- Policy initiatives to improve environment like the National Conservation Strategy and Policy Statement for Environment & Development, 1992, Policy Statement for Abatement of Pollution, 1992 and National Forest Policy, 1988.

- Notification and implementation of emission and effluent standards for air, water and noise levels. Standards are formulated by a multidisciplianry group keeping in view the international standards, existing technologies and impact on health and environment.

- Identification and Action Plans for 17 categories of major polluting industries.

- Identification of 24 critically polluted areas for pollution abatement and improving environment.

- Use of beneficiated coal with an ash content not exceeding 34% irrespective of their distance from pit head.

- For controlling vehicular pollution, progressive emission norms at the manufacturing stage have been notified, cleaner fuels like unleaded petrol, low sulphur diesel and compressed natural gas (CNG) introduced.
 
 

 About 70% of the thermal power generation in the country is by coal and this coal is very high in ash content. Moreover, high ash in coal leads to various problems including adverse effect on environment. In 1989-90 when the coal consumption was 203.50 million tonnes, Carbon dioxide (CO2) emission was 428.74 million tonnes.

CO2 emission would go upto 1179.48 mt (on BAV basis) in 2010 AD on account of increased coal consumption.
In 1994-95, power stations with a total installed capacity of 48,500 MW consumed 163 million tonnes of coal and generated about 55 million tonnes of ash. This is likely to increase to 85-90 million tonnes by the year 2001-02 with the increase in coal consumption by the power stations. With the consumption of coal more than doubling in the next 15 years the additional load of incombustibles, materials like shales/stones would increase, leading to generation of much higher amount of fly ash. This suggests the need for beneficiation of that coal which will be taken to distant power houses. A study indicates that if all the power coal transported over 500 km is washed to reduce ash from 40% to 34% there will be a saving in transportation to the extent of about 30 million tonnes, besides substantial gain in reduction of CO2 emission and reduction in fly ash.

In order to improve performance of existing power station and to reduce emission of fly ash, the existing power plants will switch over to beneficiated coal. It has also been suggested that new power plants hereinafter shall only use beneficiated coal containing upto 32% ash. Three coal benefication plant with a combined raw coal input capacity of 19 MT/Annum are under implementation.

The Govt. of India has a scheme to promote the development and adoption of clean technology including waste reuse and recycling to prevent pollution in small scale industries.

Vehicular traffic is another important source of pollution in all the mega cities. The number of vehicles in these cities has increased manifold. The increase has been characterised by boom in private transport. For containing vehicular pollution, Government has taken some important initiatives in recent years. These relate to tightening of emission norms and improvement in the fuel quality specifications. Some of the measures have been implemented while others are in different stages of implementation. With the implementation of emission norms and fuel quality, specification and phasing out of old vehicles, the pollution load has decreased in Delhi during 1998-99. The impact of the measures taken in Delhi is evident from the pollution load figures presented in Table 4.2

Table 4.2: Estimated Vehicular Pollution Load in Delhi

 
 

Pollutants
Pollution Load in Thousand Tonnes
 % Reduction as compared
Without Measures
With Measures
1990-91 1995-96 1998-99 1995-96 1998-99 to 1995-96
Carbon monoxide
243
373
451
351
337
4
Hydrocarbons
82
123
148
113
115
2
Nitrogen Oxides
139
208
248
207
182
12
Sulphur dioxide
10
15
17
15
11
27
Lead
0.190
0.259
0.362
0.259
0.007
97
Particulate Matter
19
28
33
28
21
25
Total Pollution Load
394
747
897
714
666
  
Emission Load in Tonnes/day
1351
2047
2459
1957
1825
  

SOURCE: CPCB New letter Parivesh, June, '99 Vol 6(1)

Similar impact in other cities is likely to be observed after proposed measures are implemented.