1. MONITORING AND EVALUATION
    1. NATIONAL MONITORING NETWORK
Air quality monitoring is comparatively a new phenomenon in Bangladesh. Due to the acuteness of the problems caused by air pollution, the Government has taken some necessary steps for monitoring the ambient air quality. In view of this, the Department of Environment has set four monitoring stations at the four divisional towns namely, Dhaka, Chittagong, Khulna and Bogra

Dhaka is located at the center of the country. It is a mixed city of industrial, commercial and residential areas. The monitoring station in Dhaka is located at Agargaon near the Meteorological Complex at the northwestern part of the city. On the east, there is a large open space used as airfield and commercial and residential developments dominant on all other sides.

Chittagong is the largest port city located at the southeastern part of Bangladesh. Industrial and residential developments are located on the north of the monitoring station and the Bay of Bengal is on its south.

Khulna, the second port city, is located at the southwestern part of Bangladesh.

Bogra is located on the northwester part of Bangladesh. It is predominantly an agricultural area with a few industries.

The DoE time to time measures Suspended Particulate Matters (SPM), Oxides of Sulphur (SOx), Oxides of Nitrogen (NOx), and Carbon -monoxide concentrations at these stations to assess the ambient air quality. Sampling is done with a High Volume Sampler (Envirotech HVS APM-410/451). The sampler has attachment APM-411 for gas analysis. It is set at a height of 3 meters from the ground at the designated sampling points or at the stations. Air sample collection is done for at least 8 hours to comply with WHO guidelines. High-grade glass fiber filter paper (GF/A) is used in the HVS for SPM collection. SOx and NOx are measured after the collected air is passed through absorbent solutions. The absorbent solution is then analyzed by a UV/VIS spectrophotometer. The DoE uses a portable Toxic Gas Monitor to measure the CO in air.

The data collected at the sampling locations or the sampling points along the roadside are processed at the zonal monitoring station. The results are sent to the DoE head office in Dhaka where they are recorded electronically and published intermittently.

In addition to monitoring through these stations, the DoE occasionally conducts vehicular emission (SOx, NOx, NH3, SPM and CO) measurement in Dhaka City. These locations are:

 Other Monitoring Facilities Though there is no monitoring station for continuously measuring ambient air quality, but a few organizations occasionally monitors the air quality as well as emissions from mobile sources. The Department of Civil Engineering and the Department of Chemical Engineering of Bangladesh University of Engineering and Technology (BUET) have been conducting periodical ambient air quality studies since 1995 for their research purpose. The most recent one, was conducted by the Department of Civil Engineering, includes the measurement of SOx, and NOx at 14 different locations of Dhaka City at different hours of the day over a prolonged period in 1998. At present, there are other on-going projects aimed at measuring Noise Level, SPM, SOx, and NOx at different locations of Dhaka City to correlate with the traffic pattern during the sampling periods. Also, the same study is expected to measure the concentration of Lead in the SPM samples. High Volume Sampler along with portable suspended matter samplers are used by this institution for collecting SPM data. Portable Gas Monitor (Envirotech) is used for monitoring the SOx, NOx and CO. Atomic Absorption Spectrophotometer is used for measurement of Lead in SPM.

The Bangladesh Atomic Energy Commission (BAEC) and the Bangladesh Council of Scientific and Industrial Research (BCSIR) in association with the DoE occasionally conduct studies primarily aimed at measuring the concentration lead in the ambient air. The Dhaka Shishu (Children’s) Hospital also conducted research, in association with the BAEC, on the level of lead in the children of Dhaka City to study the possible impact of leaded gasoline on the same.

The data from these institutions are published in the form of thesis or publications in reputed international and national journals, which are available for further studies. These data are also published in the leading newspapers and magazines aimed at generating awareness among the citizens.

But none of such study focused transboundary issues.

 Limitations of Monitoring Network Only DoE is mandated to monitor the ambient air quality in the country. But, because of their limitations such as fund and trained manpower they can not cover all the vulnerable points. They are concentrated in Dhaka, Chittagong and Khulna only. Till now they could not monitor the ambient air quality in border areas. DoE could not even bring point sources of emission into its monitoring network due to inadequate logistic support. Sitting of Monitoring Stations The monitoring stations at the 4 divisional towns were selected on the following criteria: Since the air pollution problem is concentrated in the urban areas, the monitoring stations are placed in the urban areas. Reference stations in the rural areas are yet to be set up. Also, no monitoring facilities are available to study the stack emission from industrial sources. ACTION In Bangladesh Air Quality is being increasingly recognized as a major concern due to its rapid degradation particularly in the urban sector. The National Environment Committee, the highest body on Environment dealing with environmental issue and concerns headed by the Prime Minister, has prioritized Air Quality as a major concern for action.

Under a 5 million US$ Air Quality Management Project (AQMP) which will be launched shortly, may set up some check posts in Dhaka, Chittagong and Khulna city to monitor the emission from mechanised vehicles. Under this project, vehicle inspection, air quality monitoring, awareness raising campaign, emission inventory, training to the drivers and mechanics of all kinds of surface mechanical transports (excluding trains) will be undertaken.
 

 2.1.a Ambient Air Quality Monitoring Network Ambient air quality monitoring may have a number of objectives. One of them is to generate information on the spatial and temporal distribution of air pollution. Monitoring data are then compared against air quality standards to identify potential risks to human health or the environment. Data indicating high pollutant concentrations in certain parts of the country or during certain periods of the day (peak morning hours) or year (certain months) enable policymakers to the necessary measures aimed at reducing pollution at these locations or during these periods. Monitoring data may also help policymakers to evaluate the effectiveness of the control measures they are going to implement.

In addition, ambient air quality monitoring Display Board may help the authority to inform people about air quality. The Display Board will make the people aware to understand their health risk. Ambient air quality monitoring, if conducted over many years, can also be used to generate emission trends as an input to medium or long-term policy decisions for air quality management.
 
 

 Point Source Monitoring

Major point sources in Bangladesh are:

Since there is no point source monitoring station in Bangladesh, it is required to set up these type of monitoring station with adequate technical assistance. At least the high polluting industries should be monitored once in every three months, which will also show the pollution with seasonal variation.

To mitigate point source emission coordinated effort of the folloowing agencies is needed:


Mobile Source Monitoring

Major mobile sources in Bangladesh are:

At present DoE is monitoring vehicular emission in Dhaka city. Mobile sources monitoring will be started soon under the AQMP project in Dhaka city, Chittagong city and also in other major cities of the country. A coordinated effort of DoE, City Corporations, Bangladesh Petroleum Corporation, BRTA and Traffic police is required for mobile source emission monitoring. Suggestions for Air Quality Monitoring The following monitoring techniques may be used: The choice of equipment is influenced by the following factors: 2.1.b Acid Rain Monitoring In Bangladesh, there is no acid rain monitoring station. The responsibility of acid rain monitoring can be bestowed upon the Meteorology Department of the Government of Bangladesh with adequate technical and financial support. 2.1.c Dissemination of Monitoring Data DoE has a plan to disseminate emission data on SOx, NOx, NH3, SPM and CO through Electronic Display Board in Dhaka, Chittagong and Khulna cities under the World Bank financed project, AQMP.

At present, Data can only be obtained from DoE in hard copy.

Regarding data dissemination suggestions are as follows:

Environmental Index should be announced everyday through Radio and Television news same as weather forecast.

Environmental Data should be disseminate through daily newspapers.

Better coordination regarding environment related information should be established among Government Organizations, Non-government Organizations, Independent Research Organizations and Universities.

Publication of Journals, Magazines, Books on air pollution issues should be encouraged by the Government.

The Government should sponsor a Web page on environmental issues.
 
 

 2.1.d Proposed Monitoring Stations Existing monitoring stations at four locations (Dhaka, Chittagong, Khulna, Bogra) is insufficient to depict the air pollution picture of Bangladesh. To assess the air quality, it is recommended to set up monitoring stations at least in six divisional headquarters and in the main towns in border areas of Bangladesh. Moreover, industrial towns are also needed to be covered by the monitoring network. The proposed monitoring stations are as follows:

Divisional Cities:

Sylhet, Rajshahi, Barisal Important locations in boarder area: Panchagar, Tetulia, Meherpur, Satkhira, Teknaf, Comilla (Bibirbazar and Chouddagram), Brahmanbaria, Feni, Sherpur, Lalmonirhat, Industrial areas:

Tongi, Narsingdi
 
 

 Existing and proposed monitoring stations are shown in the Map-2.
2.2 NATIONAL EMISSION INVENTORIES 2.2.a Emission Inventory:

Air pollution originates from the emissions of mobile, stationary, and natural sources. The contribution of each source type is site-specific. The systematic collection and compilation of detailed information about pollutant emissions in a given area is referred to as an "emissions inventory." An inventory should contain as much information as necessary on the type of sources, composition of emissions, and rates of emissions for various pollutants.

2.2.b Present Status of Emission Inventory in Bangladesh

No proper emission inventory on the emissions of SOx, NOx,, NH3 and SPM is made in Bangladesh, other than a few comparative study on mobile sources and area sources emission. The appropriate technology in this regard is yet to be set up.

However this study finds that the sulphur deposition in the air of Bangladesh may be originated from coal burning in the brick kilns, and also from burning petroleum products.

Brick Kilns

According to Bangladesh Environment: Facing 21st Century (Philip Gain, 1998), two billion bricks are produced every year in Bangladesh. From another source (BEN Digest) it is found that about 8000 brick kilns are located throughout the country, mainly in the sub-urban and rural areas.

Under the Brick Burning (control) (amendment) Act, 1992, the Government of Bangladesh has banned the use of fuel-wood and timber other than the dead roots of bamboo in brick burning. So, coal is used as fuel for brick burning. According to BBS’97, 92.5% of the country’s total imported coal (641,900 tons) are being used for brick burning. But an unofficial source said that the imported coal could not meet up the demand of coal for brick burning in Bangladesh. This situation compels the owners of brick kilns to use the smuggled coal to keep their plants operative during the season.

Another alarming factor is that the brick manufacturing season in Bangladesh is from November to April which is a dry season in the country, almost no rainfall. As a consequence of this, emissions from brick kilns are spreaded over the atmosphere without precipitating.

Neither we know the Emission Factor (EF) of burning coal nor the retention factor in ash. So, it is not possible for us to estimate the total emission of sulphur and pollutants from this sector. The country does not have any proven technology to mitigate the problem of sulphur deposition from this sector. Further studies are required to address this issue.

For an assumption of sulphur deposition from coal burning in the brick kilns, the contents of sulphur in the coal used is given below:
 
 

 Estimation of Suphur Contents of Coal Used in Bangladesh in 1999 Contents of sulphur in coal in Bangladesh is 0.57% which is yet to be explored. At the moment coal used for brick making are imported from India. Sulphur content of these brick is about 1.4%. In Bangladesh, 533,000 tons of coals were used in brick kilns in 1999 whose sulphur contents was 7,462 tons i.e 7.46 Gg. Consumption pattern of coal is given in table 2.1which shows a positive trend. Table-2.1 Consumption Pattern of Coal

Year
Quantity

‘000 (m.t.)
1990
500
1991
158
1992
150
1993
60
1994
49
1995
521
1996
352
1997
646
1998
491
1999
533
2000
576
2001
619
2002
662

Source: GSB and BBS Petroleum Products / Mobile Sources

Sector wise consumption of petroleum products in 1996 is given in the following table-2.2.

 Table-2.2 Sector-wise Consumption Of Petroleum Products For 1996


 
 

Sector
Quantity 

Thousand m.t.
%
Power
250
10
Industry 
152
6
Agriculture 
398
16
Domestic 
456
18
Transport 
1228
50
Source : Bangladesh Petroleum Corporation
 
 

The above table depicts that 50%of the total petroleum products are being used by the transport sector followed by domestic, agriculture, power and industrial sectors respectively. It indicates that the vehicular emission is the major cause of air pollution in the country, particularly in the urban areas.
 
 

 Projected demand of petroleum products upto 2002 is given in table-2.3.

Table-2.3 Projected Demand of Petroleum Products
 
 


 
 
 
 
Year 
1997
1998
1999
2000
2001
2002
Quantity
2935
3393
3767
4147
4531
4939

Though we do not know any of the process emission factors of the above sectors, but it can be predicted that the transport sector is the main source of emission of pollutants. This is a mere prediction. It is yet to be determined what are the main sources of air pollution in the country.

Only an assumption can be made from the diesel used (764,000 m. tons) in1999 for road transport whose sulphur contents was about 76,440 tons (1% of mass). It indicates that vehicular emission may be the major cause of sulphur deposition in the air.

We do not have proper technology, trained manpower and adequate fund to overcome these problems. So, further studies are required to mitigate the problem of air pollution by taking necessary actions.

Fuel Quality:

Sulphur contents of different fuels available in Bangladesh are are as follows:

Motor Gasoline-premium Max. 0.1 mass%

Motor Gasoline-regular Max. 0.1 mass%

High Speed Diesel (HSD) Max. 1.0 mass%

Low Sulphure HSD Max. 0.5 mass%

Light Diesel Oil Max. 1.0 mass%

High Sulphur furnace oil Max. 3.5 mass%

Kerosine Max. 1.0 mass%
 

Availability of Emission Data

No official emission data is available from the concerned authority, other than some research done by different universities and research institutions. One such data is given in the table-2.4 . The study was conducted by A. K. Azad Khan and T. Kitada of the Department of Ecological Engineering, Toyohashi University of Technology, Japan

In this study, SO2 and NO2 emission from various possible sources were compiled in winter, 1995-96 in Dhaka. The emissions were spatially allocated on 2 km X 2 km sq. grids on the basis of road traffic flow rate, location of specific activity, population density etc.

Table 2.4. Daily fuel consumption and estimated SO2 and NO2 emissions by various sources in Dhaka in Winter 1995-1996
 
 Source
 Fuel
 Emission factor (kg t-1)**
 Amount of emission

(T d-1)
 
Type
 Amount (t d-1)
SO2
NO2
SO2
NO2
Traffic vehicle+ Diesel oil 1395 28.8 27.4 40.17

(55.8%)

 38.22

(54.5%)
Brick field+ Coal

Wood

Furnace oil

 1430

536

107

 9.61

0.86 (kg toe-1)

64

 7.5

6.0 (kg toe-1)

5.09

 13.74

0.15

6.85

 10.72

1.05

0.54
          20.7 (28.8%) 12.3 (17.5%)
Industry ++ Natural gas

Coal

Kerosene

Diesel oil

Residual oil

 390X103(m3d-1)

156

49

98

49

 9.6X10-6(kg m-3)

9.61

4

28.8

64

 8800X10-6(kg m-3)

7.5

7.46

9.62

5.84

 0.00374

1.5

0.196

2.82

3.14

 3.43

1.17

0.365

0.942

0.286
          7.6(10.5%) 6.19(8.8%)
Residential++ Natural gas

Kerosene

Diesel oil

 744X103(m3d-1)

10

20

 9.6X10-6(kg m-3) 8800X10-6(kg m-3)

2.49

3.21

 0.0071

0.04

0.576

 6.54

0.025

0.064
          0.623(0.8%) 6.63(9.5%)
Navigation + Diesel oil 100 28.8 54.1 2.88 (4%) 5.41 (7.7%)
Commerce++ Natural gas  160X103 (m3d-1) 9.6X10-6 (kg m-3) 8800X10-6 (kg m-3) 0.0015

(0.1%)

 1.41

(2%)

  * Energy consumption data compiled from the report and personal communication to the respective departments .

** Kato and Akimoto (1992), except natural gas who’s emission factors have been adopted from EPA (1973, 1985).

+ Estimated from total number of cars. Brick fields and navigation vessels, and energy consumption by one unit of each type.

++ Estimated from total energy consumption by each sector.

% Represents total percent from a sector with respect to total SO2 and NO2 emissions in Dhaka.

Table-2.4 summarizes the amounts of SO2 and NO2 emissions due to fuel combustion by various activities, shows the primary source of SO2 is traffic vehicle (55.8%) ; followed by brick field (28.8%) and industry (10.5%) the remainder (about 5%) are due to navigation vessel in the Buriganga river, residential activities and commerce. Using of high sulfur containing petroleum products as fuel in cars, together with the lower maintenance quality, lead to high emission of SO2 from traffic vehicle. The primary source of NO2 emission is also traffic vehicle (54.5%), indicating its most liability to severe air pollution of Dhaka city. Brick field is the second most important source, contributing 17.5%, residential 9.5%, Industry 8.8%, navigation 7.7% and commerce3 2%. The overall per day emissions for Dhaka city in winter 1995-1996 are 72 tonnes for SO2 and 70 tonnes for NO2.

However, emissions are monitored time to time by DoE in Dhaka, Chittagong, Khulna and Bogra. It helps to compare the emission with the set national emission standard.

No emission data is available on any point source emission. It is needed to set up appropriate mechanism to make emission inventory on the emissions of pollutants from point sources.

Emission inventory on Greenhouse gases available in Bangladesh is undertaken by the Department of Environment and leading research institutes (BCAS, BIDS, BUET, & BUP) under Asia Least Cost Greenhouse Gas Abatement Strategy (ALGAS).
 

2.2.c Proposed Emissions Inventory Model:

An emission inventory contains a list of relevant air pollutants in the area, broken down by activity sector, for example, transport, industry, power agriculture etc. The inventory is usually geographical, based on the location of industries, major roads and population distribution. Depending on the level of detail of activity data, emission per sector is further divided into emission per process, technology, class of vehicles or other factors as a function of time. Input data requirements include the following:
 


Figure 2.2: Emissions module
 


 

Source: Jitendra J. Shah et al. (1997)

An emission module calculates the spatially distributed emission amounts. For example, emission can be distributed within a square-km grid system, based on the location of sources, pollution distribution an urban activity zones. The gridded emissions distribution provides input to dispersion models for calculating air pollution concentrations in the urban area by time and location. It also provides a basis for calculating the effects of specific abatement measures on air quality. The emission module may be in the form of a computerized database. ACTION
    1. National Emission Inventory: Capacity of DoE should be strengthen to develop and maintain a GIS based national emission inventory on air pollution from point sources, area sources and mobile sources.
    2. Emission Factor (EF): Emission factors should be determined which is needed to develop an emission inventory.
    3. Retention Factor (R): Technology should be developed to measure the retention in ash for various energy sources in Bangladesh.
    4. Pollutant Contents: Contents of pollutants in fuel used in Bangladesh should be identified beforehand. It is also necessary for calculating emission factor.
    5. Net Calorific Value(C): Capacity should be developed to determine the net calorific value for energy sources.
Regional cooperation: For the regional cooperation all the member countries should have easy access to the information on emission inventory of every country.