Twelve factors influencing sustainable recycling of municipal solid waste in developing countries

Sustainable management of solid waste is a global concern, as exemplified by the United Nations Millennium Development Goals (MDG) that 191 member states support. The seventh MDG indirectly advocates for municipal solid waste management (MSWM) by aiming to ensure environmental sustainability into countries’ policies and programs and reverse negative environmental impact. Proper MSWM will likely result in relieving poverty, reducing child mortality, improving maternal health, and preventing disease, which are MDG goals one, four, five, and six, respectively (UNMDG, 2005). Solid waste production is increasing worldwide as the global society strives to obtain a decent quality of life. Several means exist in which the amount of solid waste going to a landfill can be reduced, such as incineration with energy production, composting of organic wastes, and material recovery through recycling, which are all considered sustainable methods by which to manage MSW. In the developing world, composting is already a widely-accepted method to reduce waste fated for the landfill, and incineration for energy recovery can be a costly capital investment for most communities. Therefore, this research focuses on recycling as a solution to the municipal solid waste production problem while considering the three dimensions of sustainability environment, society, and economy. First, twenty-three developing country case studies were quantitatively and qualitatively examined for aspects of municipal solid waste management. The municipal solid waste (MSW) generation and recovery rates, as well as the composition were compiled and assessed. The average MSW generation rate was 0.77 kg/person/day, with recovery rates varying from 5 – 40%. The waste streams of nineteen of these case studies consisted of 0 – 70% recyclable material and 17 – 80% organic material. All twenty-three case studies were analyzed qualitatively by identifying any barriers or incentives to recycling, which justified the creation of twelve factors influencing sustainable municipal solid waste management (MSWM) in developing countries. The presence of regulations, enforcement of laws, and use of incentive schemes constitutes the first factor, Government Policy. Cost of MSWM operations, the budget allocated to MSWM by local to national governments, as well as the stability and reliability of funds comprise the Government Finances factor influencing recycling in the third world. Many case studies indicated that understanding features of a waste stream such as the generation and recovery rates and composition is the first measure in determining proper management solutions, which forms the third factor Waste Characterization. The presence and efficiency of waste collection and segregation by scavengers, municipalities, or private contractors was commonly addressed by the case studies, which justified Waste Collection and Segregation as the fourth factor. Having knowledge of MSWM and an understanding of the linkages between human behavior, waste handling, and health/sanitation/environment comprise the Household Education factor. Individuals’ income influencing waste handling behavior (e.g., reuse, recycling, and illegal dumping), presence of waste collection/disposal fees, and willingness to pay by residents were seen as one of the biggest incentives to recycling, which justified them being combined into the Household Economics factor. The MSWM Administration factor was formed following several references to the presence and effectiveness of private and/or public management of waste through collection, recovery, and disposal influencing recycling activity. Although the MSWM Personnel Education factor was only recognized by six of the twenty-two case studies, the lack of trained laborers and skilled professionals in MSWM positions was a barrier to sustainable MSWM in every case but one. The presence and effectiveness of a comprehensive, integrative, long-term MSWM strategy was highly encouraged by every case study that addressed the tenth factor, MSWM Plan. Although seemingly a subset of private MSWM administration, the existence and profitability of market systems relying on recycled-material throughput, involvement of small businesses, middlemen, and large industries/exporters is deserving of the factor Local Recycled-Material Market. Availability and effective use of technology and/or human workforce and the safety considerations of each were recurrent barriers and incentives to recycling to warrant the Technological and Human Resources factor. The Land Availability factor takes into consideration land attributes such as terrain, ownership, and development which can often times dictate MSWM. Understanding the relationships among the twelve factors influencing recycling in developing countries, made apparent the collaborative nature required of sustainable MSWM. Factors requiring the greatest collaborative inputs include waste collection and segregation, MSWM plan, and local recycled-material market. Aligning each factor to the societal, environmental, and economic dimensions of sustainability revealed the motives behind the institutions contributing to each factor. A correlation between stakeholder involvement and sustainability existed, as supported by the fact that the only three factors driven by all three dimensions of sustainability were the same three that required the greatest collaboration with other factors. With increasing urbanization, advocating for improved health for all through the MDG, and changing consumption patterns resulting in increasing and more complex waste streams, the utilization of the collaboration web offered by this research is ever needed in the developing world. Through its use, the institutions associated with each of the twelve factors can achieve a better understanding of the collaboration necessary and beneficial for more sustainable MSWM.

La Yeguada volcanic complex, western Panama : an assessment of the geologic hazards using new 40AR/39Ar Ages

La Yeguada volcanic complex is one of three Quaternary volcanic centers in Panama, and is located on the southern slope of the Cordillera Central mountain range in western Panama, province of Veraguas. To assess potential geologic hazards, this study focused on the main dome complex near the village of La Laguna and also examined a cinder cone 10 km to the northwest next to the village of Media Luna. Based on newly obtained 40Ar/39Ar ages, the most recent eruption occurred approximately 32 000 years ago at the Media Luna cinder cone, while the youngest dated eruption at the main dome complex occurred 0.357 ± 0.019 Ma, producing the Castillo dome unit. Cerro Picacho is a separate dome located 1.5 km east of the main complex with a date of 4.47 ± 0.23 Ma, and the El Satro Pyroclastic Flow unit surrounds the northern portion of the volcanic complex and has an age of 11.26 ± 0.17 Ma. No Holocene (10 000 years ago to present) activity is recorded at the La Yeguada volcanic complex and therefore, it is unlikely to produce another eruption. The emergence of a new cinder cone is a possibility, but the associated hazards tend to be low and localized, and this does not pose a significant threat to the small communities scattered throughout the area. The main geologic hazard at the La Yeguada volcanic complex is from landslides coming off the many steep slopes.

Eruptive history of Maderas volcano using new 40Ar/39Ar ages and geochemical analyses

Maderas volcano is a small, andesitic stratovolcano located on the island of Ometepe, in Lake Nicaragua, Nicaragua with no record of historic activity. Twenty-one samples were collected from lava flows from Maderas in 2010. Selected samples were analyzed for whole-rock geochemical data using ICP-AES and/or were dated using the 40Ar/39Ar method. The results of these analyses were combined with previously collected data from Maderas as well as field observations to determine the eruptive history of the volcano and create a geologic map. The results of the geochemical analyses indicate that Maderas is a typical Central American andesitic volcano similar to other volcanoes in Nicaragua and Costa Rica and to its nearest neighbor, Concepción volcano. It is different from Concepción in one important way – higher incompatible elements. Determined age dates range from 176.8 ± 6.1 ka to 70.5 ± 6.1 ka. Based on these ages and the geomorphology of the volcano which is characterized by a bisecting graben, it is proposed that Maderas experienced two clear generations of development with three separate phases of volcanism: initial build-up of the older cone, pre-graben lava flows, and post-graben lava flows. The ages also indicate that Maderas is markedly older than Concepción which is historically active. Results were also analyzed regarding geologic hazards. The 40Ar/39Ar ages indicate that Maderas has likely been inactive for tens of thousands of years and the risk of future volcanic eruptions is low. However, earthquake, lahar and landslide hazards exist for the communities around the volcano. The steep slopes of the eroded older cone are the most likely source of landslide and lahar hazards.