Clouded Sampur | Daily News

Clouded Sampur

Sampur coal power plant

As per modern myth, school texts, and national atlases, the wind blows from the North-East over Eastern Sri Lanka as the year ends. Even the birds know it. The transcontinental migrants draft on the North-East lies to steer to Hambantota for the Siberian winters. But the analysis of atmospheric pollution in the Environmental Impact Assessment (EIA) for the coal burning power plant (CBPP) proposed at Sampur in Trincomalee is based on wind blowing from the East. On this discrepancy rides not only the credibility of the EIA but unexamined impacts of profound consequence.

Coal burning power plants release dust and pollutants (Sulphur Dioxide (SO2), Nitrous Oxide (N2O), Carbon Dioxide), and toxins such as Mercury into the atmosphere. The Sampur plant is projected to emit 4 million tons of CO2, 10,000 tons of SOx, 10,000 tons of N2O, 1700 tons of other particulate matter, and other toxins every year even with the cleanest coal and with an additional scrubbing unit for air. These are monumental quantities that cry out for serious attention.

To support these assertions, the consultants from New Delhi, Mantec Ltd, rely on a computer model which tries to mimic the venting of these chemicals into the atmosphere via a chimney that is 135 metre tall. In the EIA, claim that the pollution levels will be tolerable at ground levels. Such computer models are built on vast generalizations and shaky assumptions. To mitigate the shortcomings, all available data should be used after careful quality control. The Sampur EIA report used only a few hundredths of the available wind observations, and did not either undertake or report on quality controls. The validation studies that was undertaken was limited as well.

As signaled earlier, a particularly perplexing aspect of the analysis is that it takes the wind to blow predominantly from the East or South-East during the “North-East Monsoon”. Mantec relies on one year of observations at Sampur by the CEB starting in December 2012 and another month of their own measurements starting on September 28, 2011.

If the wind is from the North-East over Sampur, it shall entrain the pollutants into the slopes of the central mountain ranges from Ritigala, Knuckles, Hanthana to Namunukula. There are profound consequences as mountains amplify the impacts of pollutants on atmospheric chemistry and cloud physics. This shall have damaging consequences on the air people breathe, the water supply, and ecosystems and on the quality of tea and hydro power production.

Wind over Eastern Sri Lanka during the North-East Monsoon

The wind direction for the North-East monsoon season that Mantec Ltd has presented are at odds with measurements from the Department of Meteorology, the Air Force, by the CEB and even our own institute in Kandy. The remotely sensed satellite wind observations and climate model simulations too present North-Easterly flows.

The wind in Sri Lanka has been reported by the Department of Meteorology (e.g. the Sri Lanka National Atlas 1988) as North-Easterly from December to February. The research literature from A J Bamford (Director of the Colombo Observatory (1920s) and others from the successor Department of Meteorology, Prof Thambaypillay of Peradeniya (1960s), Prof. Yoshino of Tsukuba (1970s), Dr. Suppiah of Tsukuba and CSIRO (1980s), US National Renewable Energy Laboratory, Dr Basnayake at the University of Philippines, Prof Gunaratne and myself (after 1990’s) also consistently find the wind to be North-Easterlies.

It may be that the CEB instruments observed something extraordinary over Sampur in December 2012, January and February 2013. This possibility should be entertained after cross checking the data against observations in the neighbourhood. Usually when one undertakes wind observations in a new site, stringent checks should be undertaken. Often there are instrument errors, calibration errors or simply misalignment. No such reports on quality control have been presented.

Assumptions and generalizations regarding wind in the EIA

Even if this data were accurate, there are other causes for concern. Mantec have made the following inter-locking assumptions and generalizations:

• The wind measurements in Sampur represent the wind across the East

The modelers take the wind to be uniform across the region. A much better accounting of regional variation in wind is needed to mimic nature. There are documented North to South variations; the sea-breeze affects Sampur in particular ways; mountain induced winds are known to desiccate the east (“kachchankaththa” in Tamil); and there is regional variation in the storm tracks. The average wind estimates that we prepared shown in the figure points to all this.

• Wind observations at Sampur can be extrapolated to higher elevations

The CEB instruments do not reach the high elevations that the pollutants travel to. It is hard to capture the wind profile at higher elevations without measurements. There are variations in the “atmospheric boundary layer” that vary by the hour and place, and the upper air wind profiles by month and year. The air pollution models developed in the US needs to be verified for our specific equatorial circumstances. Mantec does not present verification against the existing observations of upper air wind.

• The 2012/2013 wind observations represents wind character for the life of the coal plant

You only need to study the year to year variation of wind to know that this assumption is flaky. A straight forward issue is that in some years there are storms and even cyclones and not in other years. The wind patterns also differ during El Nino and La Nina years.

• The past can represent the future

With human induced climate change, one cannot assume that the past represents the future. The EIA does not address climate change including the risks it poses such as cloud bursts, sea level rise or changing wind patterns. Cyclonic activity, and these trajectories, intensity and frequency are changing. The North-Eastern coast is a hotspot of cyclonic and storm impacts and this aspect are not adequately addressed.

Outputs of the Dispersion Model vs Reality

Based on these data and assumptions, Mantec used a computer model to estimate dispersion of dust, nitrous oxides, sulphurous oxides and particulate matter in idealized conditions. Essentially these estimate how much of the dust shall settle around the chimneys and where – they limit their analysis to 20 km. The input wind data for December to February is consistent with what is shown in their wind rose. But if you examine the output – for example of maps of resulting Nitrous Oxides concentration shown below – the pollutants are largely dispersed towards the South-East into the sea – i.e. against the wind! All of this is far from reality.

I can only guess that the modelers have forgotten to invert the wind direction as the code calls for “going to” rather than “coming from”wind directions.

To validate these results, Mantec called upon the Industrial Technology Institute (formerly CISIR) to undertake independent dispersion studies. ITI used a commercial version of the USEPA/AMS software.

They have used the same emission data and assumptions but used wind data from a regional model - these models do not use local observations directly.

The descriptions of the results in the EIA are not adequate for comparison across seasons. The directions of dispersion appear to be misaligned with that from Mantec.

The magnitudes of pollution are several times more than that from Mantec. The EIA does not reconcile the discrepancies.

What can we infer?

Regional wind and rainfall in the North-East Monsoon

As the North-Easter lies advect moist air up the mountains, the water vapour condenses around impurities and smaller droplets grow and agglomerate to form clouds. When these droplets are large enough to sufficiently large sizes that break and fall. All this happens about 10-20 km in the windward direction from the mountain peak.

At the present the air in Eastern Sri Lanka is pristine and this aids the formation of heavy enough droplets.

Increase the pollution with a Coal Burning Power Plant, and it shall give too many sites for condensation and the droplets while more numerous shall be so small that it does not precipitate as much.

Impacts of pollution streams into the mountain slopes

North-Easterly winds shall carry pollutants released at the top of the chimneys into the mountains. Very small particulates and aerosols can undermine the cloud formation, reduce solar radiation, and change evaporation across the region.

The sulphourous and nitrous oxide emissions along with the heavy metals can change the atmospheric chemistry and lead to toxic rainfall.

There is a history of such impacts from coal plants across the world. These have far reaching consequences affecting our climate, the health of humans, ecosystems, water supply, and air, the quality of tea, agriculture, and hydro power generation.

The air pollution regulations in Sri Lanka are designed to be legally enforceable.

The focus simply on air concentrations at the ground-level without reference to the upper air leaves loopholes. – Important natural features such as the bio-concentration and the influence of mountains.

They provide developers with work around that defeats the spirits of the regulations – such as just raising the height of the chimneys.

Two decades back, Prof Oliver Illepurama’s research group undertook studies in Kandy and reported that air pollution levels for these gases were hazardous – things have only got worse since.

Thus in the only place we have data, we can be sure that the impact of additional pollution in Kandy from Sampur will affect human health.

Assumptions and generalizations

The analysis of the dispersion of dust and pollution is built on shaky assumptions and vast generalizations.

A much more technically competent and professional job in terms of using the available data, referring to the available research and being upfront of the limits of the analysis was possible.

Some of these shortfalls could have been pointed out if there had been enough time for public scrutiny, and if adequate expertise had been deployed in assessment.

Learning from the Norochcholai and other Coal Burning Power Plant

The Norochcholai power plant has been poorly run and the people in the neighbourhood and ecosystems have been impacted with dust and pollution well beyond the rosy projections given in the EIA when the wind blows from the South-West.

As disastrous as the impacts are at Norochcholai, it can be worse and wide ranging with the Sampur power plant. The configuration of the wind field and topography of Sri Lanka (consult the figures) is such that the pollutants are entrained away from our mountains in Norochcholai but not Sampur.

Some argue that the combustion technology and air scrubbing system is more advanced at Sampur and there is clean coal burning and all of that. Similar promises were made in various other power plants.

As the New York Times documented this month, a model “clean technology” coal power plant started only three years ago in Mississippi, USA, has only left failure and massive pollution. No one was held accountable.

Neglected weather and climate related risks

The EIA has also been narrow in addressing the range of weather and climate related risks. Among impacts not addressed are:

- impacts on cloud formation

- of air pollution accumulation over Sri Lanka (into the so-called “Asian/Atmospheric Brown Cloud”)

- impacts on local and regional atmospheric chemistry

- of weather related disasters and breakdowns on pollution

- weather and climate based disaster risks

- of sea level rise, changes in wind patterns and cyclonic activity due to climate change

Let’s side-step the argument made by some that we are within our rights to pollute the global atmosphere because others have done worse.

We can all agree that we should not pollute our own atmosphere – or even the atmosphere of those who live around Trincomalee and the North-Central, Eastern and Central Province.

We can even convince folks that we should not contaminate our regional atmosphere.

What we put in the regional circulation system known as the “Hadley cell ” above us just accumulates from year to year albeit with some leakage.

It also compromises our ability to address the risks from the regional and global polluters which we presently are quite blind to.

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