Home Composting - An Individual Environmental Responsibility

As urban India is witnessing unprecedented growth, our cities are also confronted with increasing quantities of municipal solid waste across the country. Heaps and mountains of garbage characterise the landscape of urban India. Delhi, the capital city itself is generating around 7000-8000 metric tonnes of mixed municipal solid waste every day and it is estimated that daily waste generation across the country is of the order of 120,000 metric tonnes. This is expected to double by 2015 and quadruple by 2025. Unfortunately the municipalities of large and small cities alike are unable to handle this mounting crisis as they do not have adequate resources to collect, transport, treat and safely dispose of the waste. As a result of systemic limitations, a large part of the waste is not collected and it is found accumulating within residential areas. The other part which is collected and transported is disposed of in open dumps on the outskirts of the towns, along highways, near river banks, etc. Among others, because land is scarce and expensive, municipalities have not been able to construct sanitary landfill sites, and as a result they resort to unscientific methods of disposal. Open disposal of waste is unsafe because it creates breeding grounds for pathogenic bacteria, viruses and other disease vectors which adversely affect public heath. Diseases that can be spread because of poor solid waste management include dysentery, viral and bacterial diarrhoea, gastro-enteritis, typhoid, trachoma, plague, typhus, salmonella, leptospirosis, filariasis, malaria, tapeworm, etc. Open dumps also cause river and groundwater pollution and release odour which lead to severe environmental and psychosomatic health impacts on the surrounding communities. Decaying waste in dumps and more so in the landfills also releases methane - a powerful green house gas, which contributes to global warming. Last but not the least, because open dumps attract scavenging birds, they are a major threat to air traffic as many a times accidents take place when birds hit aircrafts near the airports.

In order to address this growing public health and safety concern, the Foundation for Greentech Environmental Systems has developed an alternate approach which involves motivating urban residents to start exercising their ‘Individual Environmental Responsibility’ by adopting the ‘Earth Friendly Green Hobby’ of ‘Home Composting’ and thereby evolve as concerned ‘Earth Citizens’.

In this approach, the biodegradable kitchen waste (whatever a cow can eat!) from a house is put in the Green Earth Machine (GEMÔ) – an improvised bin of 100-150 litre with plenty of holes for composting which has been developed by the Foundation. A GEMÔ is designed for Indian conditions such that it can absorb 1-2 kg/day of vegetable waste from a typical family on a continuous basis, all round the year. The GEMÔ works on completely natural forces - it requires no energy, chemicals, earthworms or bacterial solutions; it works under aerobic conditions and transforms the waste into a good quality compost.

The art and science of ‘Home Composting’ requires maintaining a balance between vegetable kitchen waste, dry leaves (or waste paper, cartons boxes, etc.), moisture and mixing the contents once a fortnight with a rod or a garden rake. From time to time one can sprinkle garden soil, compost, ash or neem khali (de-oiled cake of neem seeds). First compost will come out in about 3 months and then every month one can take out small quantities. Users can integrate this practice with or cultivate the hobby of gardening and derive joy from doing good for the environment.

For the motivated individuals, this practice represents sacrificial offering to the Mother Earth which one can perform by chanting the mantra “Peace be in the universe, peace be on the Earth, peace be in the water, peace be in the herbs and vegetation and peace be everywhere…” which is normally done on completion of a Hawan. For a municipality, this represents an ultimate form of community participation and decentralised solid waste management which offers reduction in cost of collection, transport, treatment and disposal.

To promote this practice and help clean up our cities, the Foundation for Greentech Environmental Systems has launched a War on Waste, set up a Compost Help Line 011 2697 4941 in Delhi and a created a website http://www.green-ensys.org/. Over last 2 years it has enabled about 500 families in Delhi area to adopt this practice which enables returning kitchen waste in a humble manner back to the Earth. In this regard, the Foundation aims to create India Home Compost Network with committed NGOs and municipalities such that more cities and towns can adopt this approach and improve sanitation levels and safeguard public health respectively.

THE LAW OF DISORDER – NEMESIS FOR MIXED MUNICIPAL SOLID WASTE TREATMENT PLANTS

1. The root cause of failure of the entire range of technology options for treatment of mixed municipal solid waste is the fundamental law called the ‘Second Law of Thermodynamics’ which in simple words is called ‘The Law of Disorder’. The law says that ‘higher the disorder, the higher the need for external energy/resource input to get some thing useful out of any initiative’. If the cost of input is higher than the price or premium on the output, it is not worthwhile as an industrial venture.

2. Unlike any other industrial feedstock (e.g., iron ore, coal, etc.) the mixed municipal solid waste is characterised by a high degree of disorder – called ‘entropy’. For instance it has high moisture content, plastics, rags, soil, sand and stones, metal fines, and at times hazardous substances. Such variable and aggressive composition demands very advanced and robust equipment for pre-processing. Secondly the ‘degree of disorder’ is also not fixed – it keeps varies from batch to batch, day to day and season to season. For instance in summer there will be high silt/grit content while in Monsoon there will be high moisture levels. Therefore the pre-processing plant can not deliver a reliable and consistent output which could be guaranteed to be one hundred percent suitable round the year for feeding into a downstream ‘waste-to-energy’ plant or a ‘compost’ plant or an ‘RDF’ plant. Moreover, because of this ‘high disorder’, the equipment itself is subjected to high degree of corrosion, abrasion and therefore high wear and tear entailing frequent and costly repairs and replacements. Thus unlike an ore processing industrial plant, here the ‘feedstock’ is highly unreliable.

3. The society which generates the waste or let’s says the ‘feedstock’ for our processing plants is also characterised by a ‘high degree of disorder’. A large percentage of the population is either uneducated, unaware or unconcerned about segregation of waste. The waste is neither stored at home nor is it properly packed and disposed off in plastic bags. Efforts to bring about community awareness have not been able to bring about the desired response and the producers (householders) are not even prepared to pay a small price to the door collection service providers who helps in reducing the ‘disorder’. Further, open disposal at waste storage depots/ community collection point (or ‘Dalao’ as it is called in India) invites cattle to increase the disorder further and the monsoon adds an extra dose of moisture. Many towns are not able to control mixing of construction debris, drain silt, domestic hazardous waste, hospital waste, etc. at the Dalao’ . Thus the ‘disorder of feedstock’ starts from its place of generation/collection and continues all the way up to the dump yard and the processing plant.

4. On top of all this, we try to convince ourselves that this ‘highly disordered’ feedstock can be processed by a ‘low cost appropriate technology’. As a matter of fact, on the contrary the conventional wisdom says that it would require a much higher degree of robustness of the processing technology from the points of view equipment specifications, energy input, process control and environmental impact. Unfortunately the widely proclaimed ‘windrow’ technology for composting scores very low on all the four criterion.

5. In the backdrop of this ‘disorderliness’, it is not surprising to find a large number of failed initiatives for converting ‘waste-to-energy’ or ‘waste-to-wealth’ across the country. As a matter of fact, it needs to be emphasised and must be realised sooner than later that these initiatives are taking us nowhere but leading to ‘Waste-of-Energy’ and ‘Waste-of-Wealth’. Without harbouring any expectations of making gainful recovery (in financially viable terms as in an industrial enterprise) from the Indian mixed MSW (from where the rag pickers and the cows have taken out the last vestige of recoverables), it must be recognised that it is fit for only giving a ‘dignified burial’, i.e., safe disposal in a sanitary landfill, so as to protect environment and public health. Otherwise we will continue to experience not just the usual dysentery, viral and bacterial diarrhoea, typhoid and conjunctivitis, but more deadly versions of epidemics, e.g., gastro-enteritis, trachoma, laptospirosys, plague, typhus, salmonella, filariasis, malaria, tapeworm and trichonosis.

Asit Nema M.Tech. (Env. Engg., IIT Kanpur), M.Sc. (Sanitary Engg., Netherlands)
Director
Foundation for Greentech Environmental Systems
K-12, Sarita Vihar
New Delhi 110 076
Ph 011 4105 4084 / 2697 4941

THE CHALLENGES OF VERMICOMPOSTING

Fundamentally ‘vermicomposting’ represents one of the most ‘Earth Friendly’ ‘Ecological Sanitation’ solutions and no wonder many agencies and individuals are enamoured with the docile earthworms with regard to their capacity to convert kitchen waste (as against mixed municipal solid waste) into useful compost. There is no doubt about the capability of earthworms to devour the food left-over and other vegetable waste and in the process deliver a very homogeneous, uniform, pleasant textured and sweet smelling compost. However, in order to deliver such a high quality product, the earthworms need a great deal of care and protection. A number of well intentioned initiatives at the level of individuals, communities and even municipalities have been discontinued due to a number of external risk factors. A set of concerns, problems and risk factors are described hereunder:

1. Earthworms are very sensitive to temperature variations and require humid and shady place to work effectively. Temperature within the vermibeds/waste piles needs to be maintained within the ideal range of 20-28°C otherwise the earthworms start dieing. Typically in peak summer and winter seasons a higher rate of die-off is observed if the vermibeds are not well covered and protected. Secondly, aerobic composting being an exothermic process where the temperature in the core of a high waste pile rises beyond 55°C, it does not offer a very conducive environment for earthworms to survive. It is essentially to avoid heat build up that it is recommended to use (a) pre- or semi-digested organic waste, (b) restrict the height of vermibeds as low as 30-45 cm, (c) provide a shed of thatch and (d) cover the vermibeds with moist gunny bags to keep the army of earthworms cool.
2. The requirement of feeding pre-digested food waste entails provision of a pre-processing section with 15-30 days holding capacity. Secondly restriction on height of vermibeds (as against large windrows) translates into large area requirement for a community level treatment facility. Easy availability of land is a limitation and therefore either the throughput is restricted or the vermibeds get overloaded. A combination of overload and raw waste as feedstock results in higher die-off of earthworms.
3. Earthworms are also not comfortable under high moisture conditions. In monsoon an uncovered facility experiences higher die-off.
4. Earthworms are easy targets of predators and therefore vermibeds need to be well ‘guarded’ against centipedes, snakes, rodents, birds, hens and red ants. Generally to avoid ants, every vermibed has a ‘moat’ of water all around !!
5. It has been found that the indigenous species and soil burrower category of earthworms are not effective for direct devouring of kitchen waste. Exotic species such as Eudrillus euginiae, Eisenia foetida and Perionyx excavatus which are found to be most suitable are required to be cultured or purchased. The market rate of exotic species varies between Rs. 300 – 1000/kg of earthworms. Given the risk of predation and sensitivity to climatic factors, no wonder some agree-entrepreneurs are more interested in selling the earthworms rather than setting up a vermicomposting operation !

Once an individual or a large facility operator experiences colony die-off, he/she does not get second time motivated to procure a new batch of earthworms at the prevailing market rates and recolonise the vermibeds. There are so many uncertainties involved. And to ward them off, a good deal of care is required. Because of these reasons, it is generally found that sooner or later most of the vermicomposting initiatives are abandoned.

Further, because of the inherent uncertainties, the vermicomposting systems are not suitable for scaling up to treat large quantities of mixed MSW at ward or city level. It is understandable that these very reasons contributed to abandoning of a plant which was ambitiously designed for 400 MT/day capacity at the Devnar landfill site in 1992-93 in Mumbai.

In conclusion, municipalities should not expect a vermicomposting plant to be their end solution. Even the motivated individuals must recognise the limitations of our friendly and docile earthworms. At individual or community level one should ideally go for simple aerobic composting, letting the freindly aerobic bacteria and fungi to do the good job !!

MSW (MANAGEMENT AND HANDLING) RULES, 2000 - A CRITIQUE

1. The Indian MSW Rules, 2000 provide a framework encompassing collection, transportation, treatment and disposal of municipal solid waste. These Rules are complemented by the existing Bio-medical Waste Rules of 1998 and Hazardous Waste Rules of 1989 respectively, whereby disposal of these wastes along with usual urban municipal waste is prohibited. While the Rules are comprehensive in terms of specifying responsibilities and procedures, in the context of this report the following discussion is restricted to only treatment and disposal aspects. It must be noted that these Rules are under amendment and revised version is expected to be notified by the end of 2006.

2. As per these Rules, every municipality is responsible for providing integrated services and infrastructure facilities for solid waste management within its jurisdiction. Its responsibilities are defined all the way from preparing the community for segregated collection to inoffensive storage, transportation, appropriate processing and safe disposal from environmental and health point of views.

3. For the collection stage, the Rules recommend door to door collection of segregated waste, as well as separate collection from slaughter houses, meat and fish markets, fruit and vegetable markets, etc. with the objective of ‘managing to make use of’ highly biodegradable wastes. While horticulture waste is supposed to be collected separately and disposed off by following ‘proper norms’, the Rules do not clarify what these norms could be. Similarly no norms are specified for dairy waste management, instead reference is given to state laws. However, the Rules clearly prohibit open burning of any kind of waste during the collection stage.

EMPHASIS ON TREATMENT

4. With regard to treatment, the Rules recommend adoption of a suitable technology or a combination there of with the objectives of making use of wastes and to minimise burden on the landfill. While this is laudable and desirable from the point of view of the ‘3R’ paradigm, it is at this point that the Rules make a risky proposition and eventually create a potential situation of crossing the paradigm of ‘safeguarding public health’. For the biodegradable fraction of waste the Rules recommend treatment by composting, vermicomposting, anaerobic digestion or any other appropriate biological process so as to stabilise it. In other cases, options of incineration with or without energy recovery and pellatisation are also suggested. In case of any other state-of-the-art technologies, the Rules recommend to get the approval of the Central Pollution Control Board before developing any project.

DISPOSAL

5. For the last element in the supposedly integrated chain, i.e., disposal, the Rules recommend land filling of only that type of waste which is neither recyclable nor biologically processable. The Rules do not recommend land filling of mixed waste as long as it is found to be suitable for any processing. From that point of view, setting up of a bioreactor based landfill gas recovery system is considered not permissible and setting up a processing plant is considered to be a precondition for commissioning a sanitary landfill site.

6. Intriguingly, for these very reasons the singular scientifically developed sanitary landfill site in the country at Surat has run in to a technical controversy. The Gujarat State Pollution Control Board has not given permission for operation of this Rs. 60 million landfill because it does not have an accompanying composting plant. The Surat Municipal Corporation is not confident of being able to successfully run such a plant. As a result of this deadlock, as shown in Pictures above, the landfill site is lying unutilised for last three years and the MSW is being dumped in indiscriminate manner on adjacent plot. More intriguing aspect is the disregard of a clause in the Rules which permit disposal of mixed MSW in a landfill in the interim period before a processing plant could be set up.

7. With regard to location of the treatment and disposal facilities, the Rules recommend integration of landfill site with the processing plant and vice versa. It is noteworthy that environmental due diligence is recommended to be carried out during the planning stage in consultation with the respective Department of Urban Development such that necessary mitigation measures are incorporated and clearances are obtained by the promoter. However, it is not clear as to what category the facility corresponds to e.g., a large, medium or small scale industrial operation or a infrastructure utility and what criteria of assessment should be adopted. Among the mitigation measures, provision of impermeable liners for the landfill, leachate collection and treatment system, diversion of storm water drains and prevention of runoff into water bodies is mandatory.

LOCATION AND MITIGATION MEASURES

8. With regard to ambient air quality management at a landfill site, the Rules require installation of a landfill gas collection system from the point of view of odour control and safety of nearby properties. The Rules further go on to suggest gainful utilisation of the recovered gas through thermal application or power generation. It is intriguing that the Rules suggest this as an option while at the first place prohibiting disposal of degradables in a landfill which is the fundamental cause of gas production. When the system is not allowed for maximisation of gas generation, it is obvious that return on investment on gas recovery and accompanying power generation system will be unviable.

9. Schedule IV of the Rules lays down standards for, among others, pollution prevention from composting process and leachate discharge. For a composting plant the Rules recommend to maintain rotting waste in an enclosed area during pre-processing stage and take necessary precautions to minimise nuisance of odour, flies, rodents, bird menace and fire hazards. Secondly, the process rejects are required to be disposed off in a landfill without impairing the aesthetics of the processing area. Lastly, excess leachate after recycling is required to be treated and comply with discharge standards. However, given the current planning and design practices of the technology providers for windrow composting typically found in the country, these aspects are invariably not taken into account. As a result their environmental and social acceptance and functional sustainability is severely undermined.

The Joy of Home Composting

Across the country in large and small municipalities alike, the problem of municipal solid waste management has become a daunting task and open dumps characterise landscape on the outskirts of all cities and towns. Open dumps which grow like malignant tumours pose major threat to the public health as they are the breeding grounds of a wide range of disease vectors. Because of this feature alone, the society at large is paying a heavy price in terms of poor health, medical expenses and the reduced productivity. While the municipalities are working hard to collect and transport increasingly larger quantities of solid waste every day, they are confronted with the biggest challenge of safe disposal of solid waste as they have not been able to develop appropriate sanitary landfill sites. Moreover, wherever the treatment plants have been constructed they have been found to be unsustainable for a plethora of technical, institutional, financial, environmental and social factors and number of them have closed down. Treatment plants also do not solve the problem entirely as a large quantity of ‘inferior quality’ waste and the rejects still remains to be disposed of safely.

In this backdrop, it is increasingly becoming relevant to exercise ‘Individual Environmental Responsibility’ by adopting, among others, the ‘Earth Friendly Green Hobby’ of ‘Home Composting’. Composting is a rather simple process which almost every environmentally concerned citizen knows. However, very often composting at household level is not adopted because of perceived hassles and anaesthetic operations. It is perceived to require large space, a pit in the backyard and possible concerns of odour and insects from ill maintained pits. On the other hand, more motivated people who adopt vermicomposting soon realise that the earthworms are very sensitive to seasonal temperature variations and soon die off, predators feed on them, and the exotic species which do the job are rather expensive.

In order to address these concerns, and make the process of ‘Home Composting’ a lifestyle statement and joyful experience, the Foundation for Greentech Environmental Systems has been promoting usage of an improvised composting bin which is called the Green Earth Machine (GEM !). A GEM is a user friendly, robust and attractive bin of 100 – 150 litre capacity which works completely on natural forces. It is light, unbreakable, weather proof and does not involve any moving parts for mixing or aeration, etc. Plenty of perforations provided on the bin enable aerobic composting and the process does not require any chemical or biological additives. Its capacity is adequate for round the year operation for a typical small family of 5-6 members. When the ‘compost recipe’ is followed with little discipline, the process is odour free and transforms the so called waste into good quality ‘Home Made Compost’. A GEM can be easily installed in backyards, courtyards or roof-tops. As a matter of fact, a GEM can make ‘Home Composting’ a fine component of gardening hobby which is generally adopted by many in urban and peri-urban areas.

In order to derive joy from home composting initiative, it is necessary to follow a simple regime and a compost recipe. First rule is to put only the vegetable kitchen waste into the bin (all that a cow can eat, simple !) which we call ‘green waste’. Second rule is to maintain a good balance of carbon and nitrogen by adding dry leaves, waste paper, envelopes, egg trays, etc. (whatever is available) which we call ‘brown waste’. This balancing act is the key to avoid odour and thus maintain pleasant conditions. Third rule is to maintain layers of green and the brown waste, always keeping the browns on the top, which will avoid flies, maggots, etc. To that effect one can also sprinkle soil, ash or neem khali (de-oiled cake of neem seeds) once in a while. Fourth rule is to sprinkle small quantity of water every day on the fresh feed so as to enable the friendly bacteria to grow and start decomposing the waste. It is advisable to limit water dosage and keep the pile moist, not wet. Water content should be just like a moist sponge which when squeezed does not let a drop out. Fifth rule is to mix the contents of the bin once in a fortnight with a garden rake or a special mixing rod. To kick start the biological process, one can always add fresh compost, cow dung or a bit of butter milk as a seed. We at the Foundation for Greentech Environmental Systems consider this process akin to performing a ‘Yagnya’ or a ‘Havan’ on a daily basis for maintaining environmental peace on the Mother Earth.

Compost can be withdrawn from the opening specially provided at the bottom of the bin for this purpose. The first compost comes out in three-four months. It looks dark black and gives a soft sweet smell like soil after fresh monsoon showers. It can be buried under garden soil for 2-3 weeks for maturation. Subsequently one can withdraw small quantities of compost every month or so. Depending on the kind of feed in the GEMÔ, the compost will have certain proportion of organic carbon, nitrogen and phosphorus. One sample analysed at our end showed 60-70% organic carbon, 3% nitrogen, 2% Phosphorus and 8% Potassium. Since no heavy metal bearing waste items or pathogenic material is put in to the GEMÔ, one can be sure of a high quality compost free from any such contaminants and contraries.

The cumulative benefits of adopting ‘Home Composting’ are numerous. At the individual level it helps in discharging our ‘Individual Environmental Responsibility’ and production of high quality compost. For the municipality, it helps in reducing the loads on the collection, transport and disposal system. The waste quantity reaching the open dumps is reduced which helps in minimising generation of landfill gas which is a powerful green house gases. It also helps in gainfully utilising dry leaves and other biomass which is otherwise flagrantly burnt in residential areas. And above all, when more number of concerned and motivated citizens adopt this practice, it will lead to improvement of sanitary and hygienic conditions in habitations thereby reduced threat to public health.

To get more information on the ‘compost recipe’, please visit our website http://www.green-ensys.org/ where illustrations and answers to frequently asked questions have been provided. Since 2006 the Foundation for Greentech Environmental Systems is also hosting a compost helpline in Delhi (011 2697 4941) to facilitate the existing and willing GEM users and it is a pleasure to inform that by now over 400 households have become committed ‘Home Composters’ in Delhi, Noida and Gurgaon area. The Foundation is working on a mission called ‘War on Waste’ and it would be happy to assist interested NGOs and other agencies who would like to join the ‘India Home Compost Network’ in getting them started on this new paradigm in their respective cities and towns by providing training and other resource material.

Asit Nema

Director

Foundation for Greentech Environmental Systems