Potential Benefits of Introducing Integrated Solid Waste Management Approach in Developing Countries: A Case Study in Kathmandu City

Rapid economic and population growth experienced in last decade has brought significant increase in amount of urban waste generation in many developing countries like Nepal. Increasing waste generation created many problems including littering and dumping in and around outskirts of urban areas. Main problems associated with waste management in most developing countries are 1) low waste collection rates, 2) low recycling levels (recycling limited to informal recyclers), 3) littering, and 4) inappropriate final disposal. In addition to urban environmental pollution, inappropriate disposal causes generation of Greenhouse gasses such as methane gas and leachates from landfill sites. It is emphasized that most recycling is done by informal sector, restricted to materials having high market value like metals, paper and plastics. Here, we identify the potential environmental and socio-economic benefits of introducing organic waste recovery coupled with expansion of recycling of inorganic waste through cooperation with informal sector and establishment of a well-designed and managed sanitary landfill. Kathmandu city was used as a model case and Life Cycle Assessment tool was applied for evaluating potential environmental impacts. Four different scenarios were proposed based on feasible options that focus on organic recovery and informal recycling at transfer station prior to movement to landfill site. Scenarios were evaluated in terms of Global Warming Potential, Biochemical Oxygen Demand, final disposal waste, and recycling levels and energy recovery. We suggest that introduction of bio-gasification of commercial waste and composting of household waste coupled with enhanced recycling and sanitary landfill might provide highest environmental and socio-economic benefits.


Urban Waste Management Challenges for Cities in Developing Countries: The Case of Kathmandu City
Waste management is one of the biggest challenges in developing countries due to increasing population, rapid urbanization (i.e. changing lifestyle patterns) and industrialization (Guerrero, Mass & Hogland, 2013, Yabar, Hara, Uwasu, Yamaguchi, & Zhang, 2009. Developing Asian countries like China, India, Indonesia, Vietnam, and Cambodia have serious environmental contamination due to large amounts of municipal waste being dumped into open dumping sites on a daily basis without adequate management (Eguchi et al., 2013). Kathmandu, the capital city of Nepal ( Fig. 1) is also experiencing rapid population growth, causing a fast increase in waste generation that cannot be properly addressed by the local government. Primarily, Kathmandu is facing a significant problem in solid waste management including collection, transfer and final disposal of waste coupled with a lack of public awareness of the solid waste system, haphazard urbanization, introduction of environmental hazardous materials in the waste stream and changing consumer consumptions patterns (Alam, Chowdhury, Hasan, Karanjit, & Shrestha, 2008). Thus, Kathmandu Metropolitan city (KMC) requires renewed attention for effective management of its waste. Although this problem is serious there are only few studies on www.ccsen waste man For examp whereas S provides h be address separation for biolog organic wa 2013). Th countries) significant

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Objectives of the Current Study
The main objectives of the study are i) to highlight the benefits of improving current landfill and the introduction of new sanitary landfill; ii) to analyze the potential environmental and socio-economic benefits of organic waste treatment and recovery; and iii) based on the integrated waste management approach, to propose different scenarios that include the recovery of organic materials and recycling of other materials such as cans, papers, glass at the transfer station while promoting the formalization of informal recyclers.

Research Methodology
The study proposes alternative scenarios to improve the current situation based on Life Cycle Assessment (LCA). LCA is an analytical tool for systematic evaluation of the environmental aspects of a product or service system through all stages of its life cycle (EEA, 1997). The International Organization for Standardization (ISO), a world-wide federation of national standards bodies, has specified this framework within the series ISO 14040 on LCA (EEA, 1997). In this research two (Objective and Scope Definition and Life Cycle Inventory) out of four stages of LCA were utilized, and most of the calculations were done based on Inventory Analysis as the purpose of the study was to analyze potential environmental benefits through alternative scenarios concerning current situation of KMC for the reduction of pollutants.

Structured Interviews
Interviews were conducted with different government personnel from KMC, Solid Waste Management Technical Support Center, and staff from the NGOs (non-governmental organization) -Small Earth Nepal, and CBOs (community-based organization) -Women's Environment Preservation Committee (WEPCO, Nepal). Moreover, local people were randomly selected in the KMC and also at the landfill area of Sisdol for interviews (by the lead author, RKS) in order to know the current situation of Kathmandu`s municipal solid waste. Interviews with KMC officials were conducted on the following dates:

Data Collection via NGOs and Online Sources
The research included visits to various private organizations in Kathmandu city for the collection of data and relevant facts and information related to the waste in the city. In addition, a literature survey was carried out using different online databases and analysis of research papers on the topic.

Data Analysis by LCA
The collected data was analyzed using an integrated waste management approach in the modeling and subsequently LCA was used to evaluate the potential environmental impacts.

Scenarios Design
The scenarios design for KMC waste management is based on the current situation where almost all of the waste is landfilled, and where the present landfill has reached its capacity. The report by (ADB 2013) and the data collected by KMC indicated that more than 60% of total municipal waste is organic and that it can be reused and recycled. The government department for Nepal`s energy strategy plan intends to promote clean energy in the form of bio-gas over other renewable energy sources. Thus, based on the above information, the scenarios were developed.
Scenario 1.  Scenario 1 is based on the present situation in Kathmandu city where almost all the waste from the household and commercial sector is taken to the landfill directly or indirectly (Fig. 4). Assuming, part of the waste that comes from households and the commercial sector is taken to the transfer station (Teku) and then to the landfill site while some waste is taken directly to the landfill site (Fig. 3). Informal recyclers collect some material door to door, and the material collected (paper, plastic and glass) reaches the overall recycling ratio of 3.44% as shown in Table 1. Collection is done twice a week at kerbside. The recovery of material is limited. For example, paper = 13.16 kg/household/year, glass = 30 kg/household/year, and plastic = 20.31 kg/household/year. The waste is collected once a week at kerbside. If the informal recycling is not done by the informal recycler, all the waste will go to landfill increasing the amount of incoming waste and decreasing the life of the landfill.

Collection Type
Scenario 2.

Collection Type Frequency
Kerbside: Mixed collection Once in a week  In scenario 3, it is assumed that the local government allocates a specific day once a week for local people to place recyclable materials at allocated spots. The informal recyclers are formalized by the government who then collect those materials for recycling. This assumes that this initiative will double the recycling level from household which includes 14% of paper (26.31%),19% of glass (60 kg/household/year) and 13.2% of plastic (40.62 kg/household/year) (Fig. 6). The recyclable material from the commercial sector is also recycled up to 60% which includes paper (2300 tons per year), glass (548 tons per year) and plastic (1445 tons per year). It is assumed that NGOs and International NGOs encourage people to compost their organic waste. The NGO`s and the government also encourage the commercial sector to develop bio-gasification to produce electricity for supply to the city. Based on these two facts the ratio for composting and bio-gasification is determined. Out of total organic waste from households 20% of organic waste is collected which is equivalent to 14456 tons per year and is used for making compost. From the total organic waste from the commercial sector, 40% is collected which is equivalent to 2920 tons per year and is used for bio-gasification. The organic fertilizer produced from the compost and the bio-gasification plant is 100% marketable and creating a source of income. The energy released from the bio-gas plant is utilized for diverse purposes such as cooking, electricity, heating, etc. The waste collection is done 3 times a week at kerbside and to increase the recycling efficiency the waste is sorted at source. The methane gas collection is 100% of which 50% is recovered as energy. Similarly, the leachate collection is also 100%, out of which 60% is treated before being released into the environment.

Recovery
Household: Paper=26%, Glass=60%, Plastic = 40% Commercial: All 60% Figure 7. Scenario 4: Energy recovery at landfill. The figure shows 100% energy recovered from methane produced and collected at landfill. It also shows 95% of leachate is treated out of total leachate produced and collected at landfill Scenario 4 has the same recycling efficiency of recyclable materials from households and the commercial sector as the scenario 3 (Fig. 7). Out of total organic waste from households 40% of the organic waste is collected, which is equivalent to 28931 tons per year and is used for making compost. From the total organic waste from the commercial sector, 80% is collected, which is equivalent to 5840 tons per year and is used for bio-gasification. The methane gas collection is 100% and the energy recovered from it is also 100%. Similarly, 100% of leachate is also collected and 95% of it is treated before being released into the environment. Waste is collected 3 times a week at kerbside and the waste from households and the commercial sector are sorted at the source.

Medical Waste
There are incinerators in most hospitals in Kathmandu city for the management of medical waste. However, due www.ccsenet.org/jsd Vol. 7, No. 6;2014 to high operating costs the incinerators are not used. It was found that the medical waste is mixed with the municipal solid waste and taken to the Sisdol landfill site. During scenario development we consider that medical waste is not mixed with the municipal solid waste.

Compost and Bio-gas
Some of the organizations like the WEPCO in Kathmandu city are very active in the management of solid waste. WEPCO is working on community composting, vermin-composting and bio-gas production from organic waste especially vegetables on very small scale of 4 tons per day. They are also helping households around the city to make compost out of organic waste. Furthermore, they are now providing support in establishing bio-gas plants in several schools and hotels. In this research, compost and a bio-gas plant are not taken into account as it was very difficult to get information on these aspects and also the compost production is at a very small scale.

Waste from Outside the Kathmandu City to Landfill
Some waste from neighboring cities such as Bhaktapur and Kritipur also comes to the landfill site, however there is no data detailing the exact amount. In the research, all the waste from Kathmandu city is considered to have been taken to the Sisdol landfill site.

Waste Dumped on Riverbanks
At present some people dump their waste in the Bagmati River in the city, which is already polluted. The amount of waste being dumped in the river is small compared to the past according to local people residing in Kathmandu city but the exact amount dumped in the river is unknown. Therefore, waste dumped on the river bank is not considered in this research.

Waste Management and Landfill
The KMC collects most of the city waste, however, at present numerous private organizations are also involved in waste collection. The number of private organizations working in the sector has increased rapidly and is estimated to increase more in coming year (personal interview). To date there are 18 private organizations involved in the management of waste in KMC (personal interview). Furthermore, many NGOs, CBOs, and youth clubs are involved in the collection of waste (personal interview). Currently, KMC has only a single landfill which is located in Sisdol of the Okharpauwa Village Development Committee (VDC). A waste transfer station that lies between the waste collectors who unload the collected waste prior to final destination at Sisdol is around 28 km from the landfill site (Japan International Cooperation Agency, JICA, 2007). The landfill was built for a short period of 3 years through the technical and financial support of JICA but it was extended till 2012 as there was no other option for final disposal (personal interview) Unfortunately, KMC still uses the present landfill site as its final disposal site (the proposed sanitary landfill site, the Bancharedada) is yet to be commissioned. Reservation of required area of land for the proposed Bancharedada landfill has been undertaken by the government, however it is estimated that it will take around 3 years to complete the sanitary landfill (The Himalayan Times, 2013). Thus, the current situation of overload and increasing waste generation coupled with lack of proper management has turned the Sisdol landfill into a dumping site.
The addressed waste management problems are common in many cities of developing countries like India and Bangladesh. As stated the focus of the problem is on three main issues i) engaging informal recyclers, ii) composting and bio-gasification of organic waste, and iii) appropriate management of sanitary landfill. The informal recyclers were not allowed to work at the transfer station, as they were unable to reach common ground with government during negotiations. The government should involve the informal recyclers formally in the sorting, collection and recycling of materials in a well-managed material recovery facility to help increase the collection rate of recyclable and reusable materials from municipal solid waste. The informal recyclers can earn a higher income once they discover the value of a salaried job that, in turn, will motivate them to work harder. The informal recyclers should be provided with the following benefits as mentioned in the book, "Integrated Solid Waste Management: a Life Cycle Inventory" (McDougall, 2003). Those benefits as mentioned are as follows -Improved working conditions so that they do not have to sort materials in the landfill itself, health insurance, and modest affordable accommodation for informal recyclers and their families paid for out of the money they earn for separating recyclable materials.
These measures can bring many people to work as formal recyclers and give them the opportunity to increase their income by pooling recyclable materials that can be sold in bulk. There is a good example of formalization of informal recyclers in Madras (India) based around a government organization called EXNORA (McDougall, 2003) and appoint informal recyclers from the streets who then take care of street sweeping, collecting MSW,

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Discussion
In scenario 1 and 2, most of the waste is taken to the landfill with very little recovery of material being done by the informal recyclers. In scenario 1, the methane gas at the landfill is liberated in the atmosphere and there is no proper treatment of the leachate produced. In scenario 2, the generated methane gas is collected and burnt .The leachate is also 100% collected of which 60% is treated. In scenario 3, it is assumed that the local government works towards the formalization of informal recyclers and encourages people to separate their recyclable waste. This helps to double recycling compared to scenarios 1 and 2 for households. The participation of NGOs and CBOs in Khulna City (3 rd largest metropolitan city in Bangladesh) has improved the overall MSW management system especially the waste collection process from source and motivated the residents to store the waste properly and to keep the premises clean (Ahsan, Alamgir, Imteaz, Daud & Islam, 2012). Similarly, in the scenario, it is also assumed that the government, NGOs and INGOs encourage people to compost and bio-gasify for fertilizer and electricity generation to meet the electricity demands of the city. Introduction of organic waste recovery in scenario 3 at lower levels coupled with recycling of inorganic waste with 60% treatment of total leachate leads to environmental benefits at much higher levels as shown in Figures 8 to 11. Likewise, strong collaboration with all the stakeholders and recovery of 100% of the total methane and 90 % of total leachate treatment leads to even further increases in benefits in scenario 4 as shown in Figures 8 to 11. The stakeholder-based SWOT analysis for successful municipal solid waste management in Lucknow, India is a good example (Srivastava, Kulshreshtha, Mohanty, Pushpangadan & Singh, 2005). Figure 12 also shows that scenarios 3 and 4 have potential for net energy generation.

Conclusions
In this research we try to identify the potential environmental and socio-economic benefits of introducing organic waste recovery coupled with the expansion of recycling of inorganic waste through cooperation with the informal sector and establishment of a well-managed sanitary landfill. We used Kathmandu city as a model case.
The LCA was used to evaluate the potential environmental impacts. We propose four different scenarios based on feasible options that focus on organic recovery and informal recycling at the transfer station prior to movement to the landfill site. The scenarios were evaluated in terms of GWP, BOD, final disposal waste, and recycling levels and energy recovery. Our results show that the introduction of bio-gasification of commercial waste and composting of household waste coupled with enhanced recycling and sanitary landfill will result in greater environmental plus socio-economic benefits. From our results, scenarios 3 and 4 provided the highest environmental and socio-economic benefits. However in order to achieve this, the cooperation of all stakeholders is crucial. In this sense campaigns for 3 R`s awareness must be promoted and enhanced. At present the government is planning to construct a sanitary landfill (Bancharedanda Landfill) for which scenario 4 may be the best and most workable option as it solves all the present problems. Moreover, it also has a huge potential for energy generation that can help to meet the present electricity demand of KMC to some extent. Therefore, it is our belief that the government should be aware of the need to implement waste management on the basis of scenario 4 while constructing the new sanitary landfill site.