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Waste management and reuse of landfill



‘Locked down’ due to Covid-19 and going through some of my old collections, I came across an interesting publication as titled above. As this subject is relevant today, concerning climate change and renewable sources of energy, I quote the 11 suggestions made in the introduction, for the information of the authorities interested.

1. Total landfill management concept – With available space for landfills declining daily and concerns over population and dwindling natural resources; a Total Landfill Management Concept covering handling, recycling, composting, extraction and use of gases and maintenance and re-use of sanitary landfills is becoming vital.

2. Landfill gas – Anaerobic decomposition of organic solid waste in the landfill environment produces landfill gas [LFG]. LFG mainly consists of methane and carbon dioxide, both of which are odorless, Trace concentrations of other volatiles, often maladdress or toxic gases, are also found in LFG. LFG can migrate through soil into structures located on or near landfills. Since methane presents a fire or explosive threat, LFG must be controlled to protect property, and public health and safety. Also, many jurisdictions require landfill owners/operators to reduce reactive organic gas emissions to improve regional air quality, Thus, engineered solutions are needed to efficiently and safely monitor, collect, and process landfill gas.

3. Solid waste management planning – As existing landfills near capacity, as less land becomes available for the siting of new municipal solid waste [MSW] landfills, and regulatory agencies adopt stricter rules on waste disposal, or jurisdictions are facing the need to have a solid waste management plan. Unlike plans in the past, these plans are focusing on more than just collection and disposal of MSW, such as recycling, resources recovery, waste-to-energy and incineration, and examine other methods for reducing waste at the beginning of the cycle – i.e. less packaging, requiring biodegradable wrappings [bottle bills etc.

4. Waste composition studies – Waste composition studies are performed for a number of reasons, one of which is the most common – as a start towards recycling programs. Waste composition studies can assist solid waste management departments

5. Recycling – With available space in landfills declining daily, and concerns over population and dwindling natural resources growing, many communities are looking for recycling as one way to ease the strain created by increasing solid waste. Assisting communities in determining the most economically feasible and efficient method of handling recyclable materials. Several steps are involved in determining what recyclables exist in the waste stream. Evaluating the market to discover what are the current and projected needs for recyclables, comprehensive planning so implementation of a recycling plan goes smoothly and fits in with the overall goals of the community, and siting design of the recycling facility.

6. Material Recovery Facilities [MRFs] – Material recovery facilities, also sometimes called separation facilities, can be multi-million dollar installations with sophisticated, automated sorting, baling, crushing , wash-down machines or an empty building renovated with a conveyor and magnetic separator. The size and types of equipment of a MRF is determined by the usage – is the facility only used by the residents of a town, by a large city or country, or is it regional?. Much of what a MRF accepts is dictated by supply and demand and recycler’s requirements. One of the keys for designing a MRF is to design the flexibility as the demand for different types of recyclable grows.

7. Patented Technology for Conversion of Non-Organic Waste [Plastics etc] into Composite Structural Material – This process uses polypropylene, plastic and similar waste materials combined with chain fibers from biomass [wood, straw etc] to produce lightweight composites, which can be used for earth filling, building construction etc. The chemical and mechanical action of the process leads to steam explosion of the biomass material, through exposing more surface area to the melting polymers which promotes entanglement and adhesion. This allows for use of 65% biomass, 25% polypropylene,1 to 2% Epolene and 2 to 3% fly ash. Together, these longer chain fibers create an improved matrix with more flexibility at lower costs due to the wide variety of biomass which may be used. By using more fiber and less polymers, a lighter weight composite results and particle size is larger due to the chain fibers. Where waterproofing and external use are the prime concerns or where Maximum strength is desired, more plastic and finer particles can be incorporated. Color can be added to assimilate natural woods such as redwood or yellow pine.

8. Transfer Stations – The siting, design and permitting of a transfer station, or a network of transfer stations in densely populated areas, can be difficult. Emotionally-charged issue for a community. Environmental , financial, legal, noise, traffic, aesthetics, public resistance, and health and safety concerns are some of the issues that must be dealt with when siting and designing a transfer station. Other considerations include hauling distances, collection vehicle arrival times and discharges rates, the needed tipping floor and loading area, etc. As the transfer station is one component in a solid waste management program, other vehicles, such as combining a waste transfer station with a recycling/or resource recovery facility must be taken into account.

9. Composting- Composting is becoming an important part of the recycling programme. Communities are finding it a useful tool to both keep yard waste out of the land fill, and to promote natural, and economic fertilisation of vegetable and flower gardens in urban and suburban areas. A plant of the solid waste management plan being conducted, strategy. The USEPA has conducted studies to determine if different types of composts [yard wastes, sewage, sludge, water waste sludge, food waste] can be processed for land cultivation and land reclamation purposes

10. Landfill Engineering – Landfill engineering assignments typically involve many elements, including – Siting of new landfills, – Geological and hydrogeological investigations. Environmental studies [ecology. Wetland, etc], Concept designs – Design [including leachate and landfill gas migration control and cap and cover plans]; – Operation plan – Preparation of permitting application packages and negotiations with regulatory officials. Environmental impact assessments and preparation of environmental impact reports. Closure and post-closure plans and Remedial action investigations and design.

11. Landfill Gas -Landfill gas [LFG] migration investigations, control and recovery design and continuing monitoring is absolutely necessary.




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Artificial intelligence and reality of life



by Dr D. Chandraratna

Ever since President Ranil Wickremesinghe announced his desire to use Artificial intelligence (AI) to develop all sectors, from banking to agriculture, in Sri Lanka several correspondents have enthusiastically endorsed those sentiments in the print media. There is no gainsaying that technology has already made huge inroads into our lives, the latest paradigm adopted and articulated by the developed countries is thrust upon all mankind as the harbinger of a beautiful new world. Just as in an earlier time when the liberative potential of science created an understandable anguish about its misuse, similar forebodings are felt about the future curated by the super machines. Though unlike in the earlier debates where the misuse was calculated in terms of unlikely human catastrophes the current anguish is more about its ever -present transformative potential of the human world.

Most of the developed countries in the Western world, and Australia have launched statutory guidelines in the ethical use of AI. The Chat GPT, it has been cautioned in some quarters, poses such a risk to humanity that it must be subject to stringent regulation as nuclear power. Open AI founder Sam Altman has said that within a decade AI system would be capable of exceeding human expert skill levels in every domain. Given its possibility to be powerful than all other technologies experts predict that AI poses an existential risk like nuclear energy and synthetic biology. Silicon Valley experts are talking the need for a global regulatory body like the international Atomic Energy Agency (IAEA).

In the field of education, it risks accuracy and reliability of knowledge, the sources of information, academic integrity, student learning capabilities ending up with a humanity’s self-perception. Six months after Open AI launched ChatGPT, Australian University teachers have stated that they are unable to prove students who cheat with AI because still there is no regulatory body. At a conference held in Sydney last week Senior academics have railed against AI as ‘a tool in education’ because of ethical concerns, built in biases, fake knowledge and hate speech. AI is also generating enormous wealth through education in the hands of a few white male billionaires who are living off surplus value created mostly by brown and black workers.

One Deakin University academic has said it is only a data exchange service and an academic from Macquarie University said that ChatGPT app could easily be used by weak students to obtain enough marks to pass examination. Teachers may have to use open assessments and other examination methods to evaluate students. Students may be tempted to undermine their own desire to acquire knowledge in preference to the attraction of credentials to further their career prospects. Given the fact there is in the developed world a phenomenon of ‘degree inflation’ the quality and value of higher education will diminish. If cheating with the help of AI increases one’s chances of gaining the credentials thereby reducing the lure of understanding many students will not scruple to do so.

It is also the case that AI has the potential to make many employment opportunities ‘surplus to requirements’ in the knowledge economy for AI is efficient and cost cutting. Data analytic employment in multiple industry sectors will vanish overnight. Because of the fears of ChatGPT share prices of many education organisations have plummeted overnight. With the announcement of the ChatGPT, US company Chegg, which produces homework study guides, lost heavily on the stock market with more than half its workforce facing retrenchment.

There are other dangers. The value of education as character building, knowing yourself, examining one’s life, becoming wise, which are the wider objectives of education lose their appeal. Education is reduced to a process of credentialising to make us employable. AI is driven by a few mega corporations whose commercial motives are not aligned with the wider purposes of education beyond the why and the how. Education in the AI era will be concentrating on skills for employability. It can change the current paradigm of education. AI has the potential to cultivate a narcissistic and misguided anti-intellectualism which can shut out reasoned debate on public issues.

This existential threat to our sense of personal autonomy and human agency cannot be ignored. We must legislate to protect those aspects of humanity that are exclusively human and vitally important to the functioning of democratic communities. We should be alert to the fact that AI cannot replace nuance. It is soulless, cannot feel pain or loss, has no heart and no intuition. AI like all replacements to the original will disappoint us at the crucial hour for it cannot replace years of experience, innate ability, and intuitive wisdom.

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Palm oil growers await green light for sustainable production



A young oil palm plantation having a thick legume cover crop

By Emeritus Prof. Asoka Nugawela

Palm oil is a versatile commodity. It is used in numerous products world over. The global usage in 2022/23 is estimated as 76 million metric tons. Accordingly, the average global per capita usage is in the range of 10 kg per annum. Sri Lanka too recorded similar usage during 2018/2019 period, prior to economic downturn in the country. Palm oil usage is very much higher than the usage of other vegetable oils such as coconut, soya, canola, sunflower, rape seed and olive. One major reason for the relatively high per capita usage of palm oil is the affordability to purchase and its availability. Per unit land area, the oil production is four times greater in oil palm when compared with coconut. When comparing with other crops grown for vegetable oil production it is about tenfold higher. Further, oil palm, coconut and olive are perennial crops whereas soya, sunflower, canola and rape seed are short term crops. With short term crops the capital cost component is relatively high with yearly land clearing, land preparation and planting activities to be undertaken. Oil palm with a high oil yield and having a 30-year economic life cycle has the ability to provide a relatively cheaper vegetable oil than from other crops. With perennial crops the disturbance to the soil properties and biodiversity is less than in annuals and is a positive attribute as far as sustainability is concerned.

One other reason for palm oil to be the preferred vegetable oil is because it contains both saturated and unsaturated fatty acids in almost equal proportions. Thus, it is different from coconut and other vegetable oils which contain a relatively high percentage of unsaturated fatty acids, around 90%. Palm oil with its 1:1 balance of saturated and unsaturated fatty acids is the preferred choice for many applications in the food industry.

Both the type and the number of fatty acids of fat in our diets are known to influence health and wellbeing. The present global advice is to increase the consumption of unsaturated fatty acids at the expense of saturated oils and fats. For optimal health we require a mixture of fatty acids to be present in our diet. In this context among the sources of dietary oils and fats palm oil could be viewed as a relatively better option for its ‘mixed’ fatty acid profile (saturated, mono and polyunsaturated fatty acids).

The relative advantage in the return on investment the oil palm crop is having over other plantations crops also drives the investments towards this crop. This is true for both plantation and smallholder sectors in major palm oil producing countries in the world. The profitability from different plantation crops grown in Sri Lanka under average management conditions and current agrochemical/material costs & trading conditions are summarised in Table 1. Accordingly, oil palm is by far the most profitable plantation crop in the country. (See table)

The country has a demand for palm oil as a cooking oil and also as a raw material for many other industries. The products made in these industries are essential and widely used. For vigorous growth and high yields oil palm crop should ideally be grown under tropical climatic conditions with more than 2,500 mm of rainfall per annum. The low country wet zone of the country is blessed with such climatic conditions. The return on investment is high with this crop. However, even under such a favorable business environment for this industry, the government of Sri Lanka has taken a decision to ban cultivating this crop in the country. All other palm oil producing countries in the world, i.e., more than 20, are surprised and view this as a wrong decision.

Some repercussions of this decision to ban oil palm cultivation in Sri Lanka are a). dependency on other countries to fulfill our vegetable oil need, b). loss of foreign exchange to the country by importing palm oil, c). loss of income to the potential investors, d). loss of employment opportunities and e). depriving potential smallholders, the opportunity to enhance their livelihood. Prior to the economic crisis in this country, around 200,000 MT of crude palm oil (CPO) had been imported annually. The current global market price of a metric ton of crude palm oil is around 900 US$. Thus, the foreign exchange requirement to import national crude palm oil requirement will be more than 180 million US$ per annum without freight and insurance costs.

In the past, forests have been felled to cultivate oil palm in some major palm oil producing countries. The same approach was adopted for planting other plantation crops as well in the past. Deforestation will invariably lead to further shrinking of already depleted forest cover and loss of environmental services we accrue from natural forests. Natural forests significantly contribute to depleting of greenhouses gases, to the natural water cycle and protects biodiversity, soil, catchment areas, rivers and water bodies. Due to serious negative impacts of deforestation on the environment, a worldwide lobby demanding countries to grow oil palm in a more sustainable manner was initiated. With this lobby changes are now taking place in the manner in which land is selected to grow oil palm. For most crops including oil palm, systems to certify sustainable plantation management have evolved and such certification has become a requirement for marketing of produce from plantations. Basically, issues related to cultivating oil palm had been identified, awareness created amongst parties concerned and interventions for rectification have been put in place. In Sri Lanka however, to start with there was no issue of deforestation associated with oil palm cultivation. The land for cultivating oil palm in Sri Lanka was obtained through crop diversification, a scientifically accepted approach. Even then cultivating of oil palm in Sri Lanka was suddenly banned by the government incurring the investors a loss of more than Rs. 500 million on nursery plants alone. The global lobby was against felling forests to plant oil palm. The reasons for the anti-oil palm lobby in Sri Lanka according to some environmentalists, scientists and politicians are negative impacts to the environment, loss of biodiversity, depleting soil water and threat to the existence of other plantation crops. There is no scientific basis for such allegations. But those who lobby against planting oil palm do not want to understand the difference between ecological impacts when planting oil palm subsequent to felling natural forest cover and as a crop diversification program. Various attempts made had been futile and as the Sinhala saying goes it’s like trying to wake up a person who pretends to be sleeping.

The necessity for a country to produce its own needs is more than evident now with the economic crisis the country is facing currently. With a huge disparity in outflow and inflow of foreign exchange to the country the need to produce our own requirements are very much obvious. As explained earlier in this article Sri Lanka has a conducive business environment for a successful palm oil industry. What is lacking to drive the industry forward in the country is the political will. Politicians may be fearing that a decision to lift the ban on oil palm cultivation will not be a popular decision affecting their vote base. Countries economy is currently shrinking leading significant losses in employment, falling income levels, increased inequality and government borrowings. To recover from such an economic crisis the country should not ignore viable industries that could enhance national production. A reversal to the decision to ban oil palm cultivation will lead to producing national requirement preventing the outflow of millions of dollars each year. Revenue moving out will circulate among all stakeholders of the industry helping to enhance their livelihood and strengthening the economy of the country.

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‘Modabhimanaya’ everywhere



The events relating to the recent arrest of a ‘stand-up comedian’ who is allegedly to have insulted the Buddha and Buddhism can be taken as a true reflection of how confused the Sri Lankan society is when it comes to the adoption of religion and law-and-order in their true meaning.

There is absolutely no argument about the sheer folly and callousness on the part of this person in picking such sensitive material as part of her comedy gig. There can be arguments as to whether it was intended to be as derogatory to the Buddha as it seemed on the face of it when the context and the content of that gig are considered in total. But that is completely beside the point. Even if the intention wasn’t malicious, it was a grossly stupid (moda) and improper choice for which proportionate consequences must be expected.

However, have we done any better as a society in the manner we have chosen to react to this event from either a Buddhist or a law-and-order perspective? Apart from a few sane words by a minority, what we could mostly see is an equal measure of idiocy, laced with confusion, hypocrisy, inconsistency, and hatred. The immediate reaction of some of the so-called protectors of the Buddha Sasana seems the complete opposite of the fundamental teachings expounded by the Buddha in his great wisdom. Reacting in this manner begs the question as to what exactly they’re trying to protect and from whom.

Whenever the Buddha was challenged or insulted, which seemed to have happened occasionally during his lifetime, he never encouraged his followers to lose their minds or to seek revenge. The Buddha didn’t rush to enter any defamation complaint at the royal courts either. He only did his best to make his accusers understand and see the truth for themselves. That was done with complete kindness – not with a revengeful heart.

Buddha’s teachings are so profound that his followers are supposed to become wise, stable, and strong enough to be able to handle any praise or contempt that come their way without losing their own minds. It’s therefore very unfortunate (and amusing) to see some of the “followers and protectors” of the Buddha’s teachings, including some Monks, grossly deviate from the teachings they themselves claim to follow and protect!

The law-and-order perspective in this regard also seems to lack clarity and consistency like in many other similar areas. While the provisions of ICCPR Convention were extremely progressive and well-intended, the way our local ICCPR Act is being used leaves a lot of questions than answers.

There appears to be some confusion or misunderstanding about the true intentions of this Act and under what circumstances its provisions should be used. To prevent any misinterpretation or misuse, the ICCPR Convention had clearly emphasised the need for considering the factors like the context, content, intention, potential for violent reaction, etc. before making a call. In the absence of such consistent guidelines, our ICCPR Act could easily become putty in the hands of our scheming politicians and their lackeys in the law enforcement machinery.

Haven’t we already witnessed a lack of consistency in this regard in recent times?

Upul P, Auckland

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