Following dates suggest some indication of the development of the monitoring efforts in Sri Lanka:

1995. Department of Chemistry, University of Peradeniya (UoP), started monitoring acid rain in 12 locations in the island. The sites are mainly where the rain gauges stations are located.

1997. A Sub Committee under the CA2AP Implementation Committee is appointed to give guidance and co-ordinate the air quality-monitoring programme.

Since December 1996, the NBRO has begun a continuous monitoring programme in 2 selected locations within the Colombo Municipal Council Area using the two fixed stations. A programme is being implemented to monitor 5 other selected locations around the Island using the mobile station. The mobile station is also being used to monitor air quality for consultancy services.

One of the fixed stations is located in the Fort Railway Station car park in the central business area of Colombo. The objective of locating the station here was to measure the pollution in a local area, which experience high traffic volumes. The other fixed station is located within the Meteorological Station in Colombo which is a relatively less polluted area and thus used for measuring background concentrations.

The 3 stations are equipped with the following instruments:

• Air Quality Samplers: Sulphur Dioxide, Oxides of Nitrogen, Carbon Monoxide, Ozone, Particulate (PM10)
• Meteorological Instruments: Wind Direction, Wind Speed (Horizontal & Vertical), Ambient Temperature, Precipitation, Solar Radiation

The measured data is processed by the NBRO and monthly reports are given to the CEA. The Sub Committee discusses trend reports and CEA tables the report at the main CA2AP Implementation Committee. A ‘Magi’ board is maintained within the Fort Railway Station site and the average daily sampling results are displayed. The PM10 data is also published weekly through a weekend newspaper (Weekend Express). The acid rain reports are publicised by the Department of Chemistry - UoP at seminar forums and are also given on request.
 

Responsibility of each of the organisation is as follows:
 

Institution	Responsibility
Ministry of Forestry & Environment	Main institution for policymaking and decision making. Secretary to the Ministry is responsible for chairing the CA2AP Implementation Committee meetings and to co-ordinate the implementation of the recommendations in the action plan.
Central Environmental Authority	The main enforcing institution of the ministry. Responsibilities include data dissemination, co-ordinating the monitoring programme, policy recommendations, setting standards, licensing, EIA and emergency response.
National Building Research Organisation	Responsible for operation and maintenance of the 3 monitoring stations. Reporting of the data to the sub committee and the CEA on a set period. In addition, chairing the Sub Committee on ambient air quality monitoring under the CA2AP Implementation Committee.
Other research organisations	Independent research in the field. Reports could be submitted to the CA2AP Implementation Committee for action.

 

All instruments are fixed inside temperature-controlled shelters. Height of the inlet manifold for gases is kept at 3m from the ground for the fixed stations and 3.5m for the mobile stations. The meteorological data are measured at a height of 10m from the ground level. Data is collected automatically every 5 minutes and stored in the data logger of each station. The NBRO downloads the data from each station periodically and conduct all analyses in-house.

Details of the fixed stations monitoring programme
 

Monitoring Station	Parameters Monitored	Monitoring Technique	Organisational Responsibility	Mode of Dissemination
Fort Railway Station, Colombo Latitude: 6.933oN Longitude: 79.833oE Frequency: Continuous using fixed station (every 5 minutes) Height from MSL: 3m  Surrounding: Urban, city centre, average building height ~ 12-15 m	SO2 NOx, NO2, NO CO O3 PM 10 Wind Direction Wind Speed (H&V) Temperature Precipitation Solar Radiation	UV Photometry Chemiluminscent Infrared Photometry UV Photometry High Volume Sampler	NBRO: Operational & Maintenance	Hard Copy could be obtained at the CEA on payment, PM10 data is published in weekend paper & Display average data on a board at the station
Meteorological Station, Colombo Latitude: 6.900oN Longitude: 79.867oE Height from MSL: 7.3m  Frequency: Continuous using fixed station(every 5 minutes) Surrounding: Urban, residential area, situated within the main meteorological site Average building height ~ 6 –10 m	SO2 NOx, NO2, NO CO O3 PM 10 Wind Direction Wind Speed (H&V) Temperature Precipitation Solar Radiation	As above	NBRO: Operational & Maintenance	Hard Copy could be obtained at the CEA on payment,

Details of the mobile station monitoring programme
 

Monitoring Station	Parameters Monitored	Monitoring Technique	Organisational Responsibility	Mode of Dissemination
Ambewela Town Latitude: 6.884oN Longitude: 80.800oE Height from MSL: 1828.4m  Frequency: Continuous for 1 week every 3 months using mobile station Surroundings: Rural, situated in the hill station. Surrounded by a plateau	SO2 NOx, NO2, NO CO O3 PM 10 Wind Direction Wind Speed (H&V) Temperature Precipitation Solar Radiation	As above	NBRO: Operational & Maintenance	Hard Copy could be obtained at the CEA on payment,
Hambantota Meteorological site  Latitude: 6.117oN Longitude: 81.133oE Height from MSL: 15.5m  Frequency: Continuous for 1 week every 3 months using mobile station Surrounding: Semi-urban area, south side open to sea, 1 km away from the town,	SO2 NOx, NO2, NO CO O3 PM 10 Wind Direction Wind Speed (H&V) Temperature Precipitation Solar Radiation	as above	NBRO: Operational & Maintenance	Hard Copy could be obtained at the CEA on payment,
Katugastota Meteorological Station Latitude: 7.333oN Longitude: 80.633oE Height from MSL: 477.1m Frequency: Continuous for 1 week every 3 months using mobile station Surrounding: Residential, trees around the site	SO2 NOx, NO2, NO CO O3 PM 10 Wind Direction Wind Speed (H&V) Temperature Precipitation Solar Radiation	As above	NBRO: Operational & Maintenance	Hard Copy could be obtained at the CEA on payment,
Anuradhapura Meteorological Station  Latitude: 8.333oN Longitude: 80.383oE Height from MSL: 92.5m  Frequency: Continuous for 1 week every 3 months Surrounding: Semi-Urban area,	SO2 NOx, NO2, NO CO O3 PM 10 Wind Direction Wind Speed (H&V) Temperature Precipitation Solar Radiation	As above	NBRO: Operational & Maintenance	Hard Copy could be obtained at the CEA on payment,
Puttalam Meteorological Station Latitude: 8.033oN Longitude: 79.834oE Height from MSL: 2.13m  Frequency: Continuous for 1 week every 3 months using mobile station Surrounding: Semi-Urban,	SO2 NOx, NO2, NO CO O3 PM 10 Wind Direction Wind Speed (H&V) Temperature Precipitation Solar radiation		NBRO: Operational & Maintenance	Hard Copy could be obtained at the CEA on payment,

H&V – Horizontal and Vertical

Department of Chemistry, UoP is monitoring at the following sites on a monthly basis on the following sites. The parameters monitored are pH, Cl^-, NO₃^- and SO₄^2-

In addition to the Meteorology sites mentioned above following site are also monitored.
 

Monitoring Station	Parameters Monitored	Monitoring Technique	Organisational Responsibility	Mode of Dissemination
Maha Illuppalama Rain Gauge Station Latitude: 8.117oN Longitude: 80.467oE Height from MSL: 137m  Surrounding: rural	pH Cl- NO3- SO42-		Department of Chemistry, UoP	On Request
Kurunagala Rain Gauge Station Latitude: 7.167oN Longitude: 80.633oE Height from MSL: 116m  Surrounding: Urban,	pH Cl- NO3- SO42-
Badulla Rain Gauge Station Latitude: 6.984oN Longitude: 81.050oE Height from MSL: 669.6m  Surrounding: Urban, hill station	pH Cl- NO3- SO42-
Bandarawela Rain Gauge Station Latitude: 6.817oN Longitude: 80.967oE Height from MSL: 1225m  Surrounding: Urban, Hill Station	pH Cl- NO3- SO42-
Nuwara-Eliya Rain Gauge Station Latitude: 6.967oN Longitude: 80.767oE Height from MSL: 1895m  Surrounding: Urban, Hill station	pH Cl- NO3- SO42-
Udawalawa Rain Gauge Station Latitude: 6o35’N Longitude: 80o58’E Height from MSL: m  Surrounding: rural	pH Cl- NO3- SO42-
Galle Rain Gauge Station Latitude: 6.033oN Longitude: 80.217oE Height from MSL: 12.5m  Surrounding: Urban, sea side	pH Cl- NO3- SO42-
University of Peradeniya Latitude: 7o15’N Longitude: 80o34’E Height from MSL: 470m  Surrounding: Semi-Urban,	pH Cl- NO3- SO42-

Source: O A Ileperuma an R M Premakeerthi (1998), Acid Rain Monitoring in Sri Lanka, A paper presented at the Workshop on Acid Rain Monitoring and Atmospheric Modelling, Kandy, Sri Lanka

2.2 Siting of Monitoring Stations

Following the initial study (1989-1992) by the NBRO on selected locations within the CMR, "hot spots" were marked for continuous monitoring. Since the number of fixed stations were limited to 2, one high concentration site (or peak station) at the Fort Railway Station and a background station in the Meteorological Department site ware selected for initial monitoring within the Colombo City. The objective was to compare the difference in the levels within the city of Colombo and to collect baseline data. Other criteria that determined the siting were availability of electricity, easy access, and most importantly security.

The Fort Railway Station site is located close to the main road that is used mostly by buses and all other sides are surrounded by buildings with an average height of 12-15 m. The station is placed about 10m from the centre of the road and is placed at 3m above the ground level. PM10 sampler is kept on top of the shelter and the inlet is at a height of 3.5m from the ground. Meteorological parameters are also measured to obtain data on the local variations.

The Meteorological Station site is located in a primarily residential area. The inlet manifold for the gas analysers is about 150m from the centre of the road and is placed at 3m above the ground level. PM10 sampler is kept on top of the shelter and the inlet is at a height of 10m from the ground. Meteorological parameters are also measured to obtain data on the local variations.

The mobile station is used for monitoring in all other locations. The station is also used for monitoring for any consultancy assignments or for any regulatory purposes. The 5 sites selected for the initial phase is along the western slopes of the hill country. Out of the 5 sites 4 are within meteorological stations. The criteria that influenced this decision was the availability of electricity and security at the stations.

For the purpose of the acid rain monitoring, the Department of Chemistry, UoP are using 12 rain gauge sites where rainwater sample is collected.

2.3 Examples of Monitoring Results

NBRO analyses the data from the 3 stations and a monthly report is given to the CEA through the Sub-Committee. PM10 data collected is given weekly to the CEA for publication in the media. A sample of the report is attached (see ANNEX 1).

The results from the acid rain monitoring at the 12 sites are as given in the table below.
 

Station	pH			Cl- (ppm)			NO3- (ppm)			SO42- (ppm)
	Min	Max	Avg.	Min	Max	Avg.	Min	Max	Avg.	Min	Max	Avg.
AP	4.89	6.97	6.00	0.31	3.73	1.63	0.00	1.99	0.74	0.00	0.38	0.05
BD	6.11	7.11	6.64	0.28	3.50	1.92	0.00	2.56	1.42	0.00	2.51	0.74
BW	5.78	6.72	6.24	0.43	4.00	1.67	0.00	0.71	0.30	0.00	3.00	0.76
CB	5.32	6.68	5.89	1.15	5.40	2.22	0.00	2.00	0.57	0.00	8.31	2.95
GL	5.35	7.90	6.45	5.40	32.12	18.06	0.00	2.66	0.90	0.00	8.60	2.44
HT	5.79	5.99	5.89	5.66	14.33	10.00	1.47	2.31	1.89	0.00	0.00	0.00
KG	4.92	6.76	6.28	1.08	7.75	4.28	0.00	1.75	0.88	0.00	1.66	5.55
MI	5.09	6.54	6.07	0.40	2.20	1.37	0.00	1.28	0.52	0.00	1.21	0.05
NE	4.36	6.96	6.18	0.00	2.51	1.22	0.00	0.93	0.28	0.00	2.82	0.40
PT	6.21	7.31	7.00	0.67	8.83	2.56	0.00	0.86	0.43	0.00	7.28	2.47
RP	5.88	6.46	6.25	0.40	1.00	0.79	0.36	5.90	0.48	0.33	0.90	0.54
UNI	4.68	7.27	6.26	0.00	20.20	2.77	0.00	0.79	0.19	0.00	5.50	0.76

Key: AP- Anuradhapura, BD: Badulla, BW: Bandarawela, GL: Galle: HT: Hambantota. MI: Mahailluppallama, NE: Nuwara-Eliya, RP: Ratnapura, UNI: University of Peradeniya

Source: O A Ileperuma an R M Premakeerthi (1998), Acid Rain Monitoring in Sri Lanka, A paper presented at the Workshop on Acid Rain Monitoring and Atmospheric Modelling, Kandy, Sri Lanka

2.4 Data Availability

The CEA has sole responsibility for dissemination of the data from the air quality-monitoring programme. Presently, monthly reports produced by the NBRO are given to the CEA. Weekly data on PM10 is disseminated to the media (Weekend Express) by the CEA. A ‘Magi" board is kept at the Fort Railway Station and the average concentrations of the various gases measured are posted daily. A half-yearly trend report on air quality is presented to the CA2AP Implementation Committee for information and for any policy decisions. At present data could be obtained from the CEA on payment by any interested institutions.

Acid rain data is available from the department of Chemistry, UoP. The data could be obtained upon request from the Department of Chemistry, UoP.

2.5 Data Quality Checks

The monitoring stations are automatically set for self-calibration using standard gases certified by the USEPA at a set time each the day. To ensure the reliability of the data, the mobile station is run parallel to the fixed stations to cross check data.

2.6 Future Developments of Monitoring Networks

Since continuous monitoring began only in December 1996, there is no proposal to add additional monitoring stations. However, there is a proposal to develop a surveillance model for Colombo and with the intention of using the mobile station to systematically monitor "hot spots" based on the out come of the model. The model would be also used to provide input into the policy process.