Identifying the key factors in increasing recycling and reducing residual household waste: a case study of the Flemish region of Belgium

Seasonal variability of the quantity and morphological composition of generated waste and selectively collected waste

Waste delivered to the Marszów Plant was tested in order to research the effect of seasonal fluctuations on the quantity and composition of generated municipal waste and on the quantity and composition of selectively collected waste. Waste samples were collected once a month from November 2019 to October 2020. The results of the analysis showed that the quantity and composition of municipal waste generated during a week are different in terms of the subsequent months of the year. The quantity of generated municipal waste per capita per week ranges from 5.75 to 7.41 kg (cap·wk)^-1, on average 6.68 kg (cap·wk)^-1. The maximum values of the weekly indicators for generating the main material components of waste per capita were higher than the minimum by several up to more than 10 times (textiles). The total quantity of selectively collected paper, glass and plastics increased significantly during the conducted research at a rate of approx. 5% per month. The level of recovery concerning this waste over the period between November 2019 and February 2020 averaged at 29.1%, and between April and October 2020 it was nearly 10% higher (39.0%). The material composition of selectively collected waste in subsequent measurement series often differed. It is difficult to link the observed changes concerning the quantity and composition of the analysed waste streams with the seasons of the year, although weather conditions undoubtedly impact the consumption and functioning models of people, thus impacting the size of waste streams.

The road to sustainable use and waste management of plastics in Portugal

As a European Union (EU) member, Portugal must comply with reductions in plastic waste. In Portugal, the 330 items/100 m of beach litter, comprising up to 3.9 million pieces and of which 88% is plastic, is higher than the EU median (149 items/100 m) and must be reduced to 20 items/100 m (94%). Integrative measures are needed to reduce littering and improve plastics' use and disposal under the circular economy. Of this 414 kt of plastic packaging waste, 163 kt were declared plastic packaging, 140 kt subjected to recycling, and 94 kt to energy recovery. The current recycling rate of plastic packaging (34%) should be improved to reach EU recycling averages (42%) and goals and to provide widespread benefits, considering revenues of 167 €/t. As a net importer of waste, Portugal could benefit from the valorization of imported waste. Besides increased recycling, pyrolysis and gasification could provide short-term alternatives for producing value-added substances from plastic waste, such as hydrogen, consistent with the National Plan of Hydrogen and improving ongoing regulations on single-use plastics. This manuscript provides an integrative view of plastics in Portugal, from use to disposal, providing specific recommendations under the circular economy.

ELECTRONIC SUPPLEMENTARY MATERIAL

Supplementary material is available in the online version of this article at 10.1007/s11783-021-1439-x and is accessible for authorized users.

A European household waste management approach: Intelligently clean Ukraine

The European-wide environmental obstacles of inefficient and unsustainable recycling systems and flows constrain household waste (HW) management, endangering the circular economy. The European 2020 strategy and ongoing environmental disasters indicate the ineffectiveness of the current HW sustainability practices. This paper introduces an artificial intelligence (AI) approach for calculating urban residual waste, based on its generation level. It reforms the current diverse and high discrepancy levels of HW residual for EU-countries and Ukraine. Adopting a k-means clustering method with a multi-criteria taxonomic development level index (TIDL), it produces uniform clusters with higher accuracy and manageability. Findings discover and remedy opaque managerial practices, enabling sustainable and environment-friendly development at national and regional levels for EU-countries. Results reveal an increased number of clusters in crisis, contributing to a methodological reference for environmental planning. In conclusion, this AI approach could have a European-wide impact on sustainable economic value-chain, converging toward an eco-friendly economy.

Predictive modelling as a tool for effective municipal waste management policy at different territorial levels

Nowadays, the European municipal waste management policy based on the circular economy paradigm demands the closing of material and financial loops at all territorial levels of public administration. The effective planning of treatment capacities (especially sorting plants, recycling, and energy recovery facilities) and municipal waste management policy requires an accurate prognosis of municipal waste generation, and therefore, the knowledge of behavioral, socio-economic, and demographic factors influencing the waste management (and recycling) behavior of households, and other municipal waste producers. To enable public bodies at different territorial levels to undertake an effective action resulting in circular economy we evaluated various factors influencing the generation of municipal waste fractions at regional, micro-regional and municipal level in the Czech Republic. Principal components were used as input for traditional models (multivariable linear regression, generalized linear model) as well as tree-based machine learning models (regression trees, random forest, gradient boosted regression trees). Study results suggest that the linear regression model usually offers a good trade-off between model accuracy and interpretability. When the most important goal of the prediction is supposed to be accuracy, the random forest is generally the best choice. The quality of developed models depends mostly on the chosen territorial level and municipal waste fraction. The performance of these models deteriorates significantly for lower territorial levels because of worse data quality and bigger variability. Only the age structure seems to be important across territorial levels and municipal waste fractions. Nevertheless, also other factors are of high significance in explaining the generation of municipal waste fractions at different territorial levels (e.g. number of economic subjects, expenditures, population density and the level of education). Therefore, there is not one single effective public policy dealing with circular economy strategy that fits all territorial levels. Public representatives should focus on policies effective at specific territorial level. However, performance of the models is poor for lower territorial levels (municipality and micro-regions). Thus, results for municipalities and micro-regions are weak and should be treated as such.

Circular Economy in Poland: Profitability Analysis for Two Methods of Waste Processing in Small Municipalities

The problem of diminishing resources on our plant is now getting due attention from the governments as well as scientists around the world. The transition from a linear economy to a circular economy (CE) is now among the top priorities. This article discusses the implementation of the circular economy paradigm in Poland through the analysis of the existing and planned mechanisms, and actions taken by the Polish government which can be replicated by other young European countries. Further, the article discusses the direction of change and projected measures planned by the Polish government to improve the quality of municipal solid waste management. In this context, profitability analysis is carried out for two methods of waste processing (incineration and torrefaction) intended for small municipalities and settlements in which district heating and trading of generated electricity are not feasible. The results of the analysis shows that torrefaction is clearly a more desirable waste processing option as a step towards the implementation of CE for civic society in the urban context, as well as profitability, in comparison to incineration. The analysis accounts for several scenarios before the lockdown caused due to the COVID-19 pandemic and after it was lifted.

Regional Differences in Municipal Solid Waste Collection Quantities in China

The rapid growth in urban population has led to a dramatic increase in municipal solid waste (MSW) generation, with ramifications more pronounced in developing countries. The regional Chinese governments have made great efforts to reduce MSW generation and collection quantities. However, the results of these efforts vary across cities. The purpose of this paper is to analyze the regional differences in MSW collection quantities. A two-level hierarchical linear model (HLM) was used to examine the variations in MSW collection quantities among 287 prefecture-level cites in China over the period from 2008 to 2017. The analysis reveals a strong negative correlation between the regional economic development level and the growth trend of MSW collection quantities. The empirical findings indicate that the level of economic development and waste collection measures are critical determinants of MSW collection quantities.

Drivers of legal and illegal solid waste disposal in the Global South - The case of households in Yaoundé (Cameroon)

Managing municipal solid waste is a challenge for many policy makers, but even more so in the Global South. Regulatory instruments are often limited, available resources are scarce and illegal waste disposal is an easy opt-out. We analyze a unique dataset regarding waste disposal choices by households in Yaoundé, Cameroon, including information on illegal waste dumping. Overall, households in Yaoundé seem to act predominantly as rational, cost-minimizing agents. While social criteria also play a role, waste disposal choices are mainly determined by the accessibility of the different alternatives. In particular the output of a multinomial logit model shows that households with (easy) access to legal alternatives such as centralized drop-off containers or curbside waste collection are less likely to dispose of their waste in an illegal manner. In addition, illegal disposal becomes more attractive when the illegal waste dumpsite is closer to the family home and transportation costs are lower. Although these results might seem unspectacular, in the context of the Global South, these findings also reveal that investing in waste collection infrastructure offers great potential in improving waste disposal, particularly in combination with other measures such as removing illegal dumpsites, incorporating pre-collection and composting into institutional programs, raising awareness and increasing the level of compliance.

Influence of four socioeconomic indices and the impact of economic crisis on solid waste generation in Europe

The standard of living and certain socioeconomic and development indices can influence solid waste generation. This potential association can aid to focus on, and to establish, appropriate policies to reduce waste generation, with waste prevention being the cornerstone of those policies so that to eventually decouple waste generation from economic growth. Although, several studies have been performed at a regional or municipal level to study the impact of socioeconomic factors on waste generation, this impact on a European scale using data of several individual special solid waste streams from the years of the economic crisis has not been studied. The goal of the work was to investigate the impact of the Gross Domestic Product (GDP), the Human Development Index (HDI), the Unemployment Rate (UR), and the CO₂ emissions on the generation rates of thirteen solid waste streams using data from ten European countries. Annual data ranged from years 2008/2009 to 2015. Regression modeling between the waste generation rates and each of the four indices was developed and significant correlations were calculated. Results revealed that nine solid waste streams were positively correlated to the GDP, with waste electronic and electric equipment (WEEE) having the strongest positive correlation. With the aid of a novel graphical methodology, the countries were grouped into "normally behaving", "affected", "preventive" and "wasteful". Greece and Portugal were the countries that belonged to the "affected" countries for most waste streams, whilst Germany and the United Kingdom belonged most frequently to the preventive countries.

Do Sociodemographic Characteristics in Waste Management Matter? Case Study of Recyclable Generation in the Czech Republic

The generation of recyclables in the Czech Republic has long been under the European average, but the proportion from municipal waste as a whole has been growing over the past few years. Previous research in the Czech Republic mainly focused on organizational or situational factors explaining recycling performance in municipalities. This study focuses on individual characteristics that are connected, among other things, to ongoing demographic changes. Currently ongoing sociodemographic development in the Czech Republic, as well as other developed countries, influence a broad range of aspects of social life, including waste generation and its structure. This paper aims at quantifying the relation between the sociodemographic characteristics of municipality inhabitants and recyclable generation. For this purpose, 13 variables describing inhabitants, households, and housing in 4897 Czech municipalities were selected that could influence the generation of recyclables according to foreign studies. Data were analyzed using multidimensional linear regression. Even though the resulting model only explains 9%, it is statistically significant and implies that sociodemographic variables can help explain recyclable generation. From this point of view, important variables are average household size, share of tertiary educated people, share of family houses, purchasing power per person, percentage of people employed in agriculture, and sex ratio. To increase the explained variability and emphasize local differences in recyclable generation, we also used geographically weighted regression (GWR). GWR results show that, to understand waste generation (at least in the Czech Republic) on a municipal level, it is necessary to also consider spatial effects and regional specifics.

The role of management instruments in the diversion of organic municipal solid waste and phosphorus recycling

Organic waste, which contains essential plant nutrients such as phosphorus, constitutes 30%–50% of municipal solid waste in developed countries. Unfortunately, much of this resource is buried in landfills or incinerated. Many jurisdictions have, therefore, adopted the diversion of organic waste and the recycling of nutrients as policy goals. We used data sets from Europe and Ontario, Canada, to explore the impact of socio-economic and management factors on the rates of organic waste diversion and examined the effect of this diversion on phosphorus recycling. Organic diversion rates were highly correlated with income in Europe and with infrastructure, such as source-separated organic waste collection, in Ontario. Significant correlations were also observed between diversion rates and the use of policy instruments such as economic incentives, legislative organic waste bans, and curbside bag limits. We estimated that 39%–63% of the phosphorus in diverted organics is returned to arable land. Ultimately, we found that although socio-economic factors influence the success of organic waste diversion, policies, accessible infrastructure, economic incentives, and legislative requirements can be leveraged to improve the recycling rate of organic waste and the nutrients they contain.

Factors influencing the recycling rate under the volume-based waste fee system in South Korea

Since the early 2000s, the Republic of Korea (South Korea) has maintained its top-rank status for its municipal solid waste (MSW) recycling rate among OECD (Organization for Economic Cooperation and Development) member countries. The volume-based waste fee system (VWF) has been considered to be the major factor contributing to the high recycling performance, and extant research has verified the positive relationship between VWF adoption and the MSW recycling rate. Nevertheless, there exists a gap in the literature, as past research has focused more on testing the positive effects of VWF rather than on investigating the determinants of recycling rates after the adoption of VWF. The current study seeks to address this gap by investigating the various factors that affect recycling rates under the VWF system. More specifically, using data from 16 regions in South Korea over a period of 11 years, this study empirically tests the effects of VWF pricing, the citizen cost burden ratio for the VWF system, and pro-environmental behavior related to VWF on the recycling rate. The findings indicate that economic incentives such as cost savings on VWF plastic bag purchases and reduced burden from paying VWF expenses result in higher recycling rates. The findings also demonstrate that pro-environmental behavior in the VWF context positively affects the recycling rate.

Support for designing waste sorting systems: A mini review

This article presents a mini review of research aimed at understanding material recovery from municipal solid waste. It focuses on two areas, waste sorting behaviour and collection systems, so that research on the link between these areas could be identified and evaluated. The main results presented and the methods used in the articles are categorised and appraised. The mini review reveals that most of the work that offered design guidelines for waste management systems was based on optimising technical aspects only. In contrast, most of the work that focused on user involvement did not consider developing the technical aspects of the system, but was limited to studies of user behaviour. The only clear consensus among the articles that link user involvement with the technical system is that convenient waste collection infrastructure is crucial for supporting source separation. This mini review reveals that even though the connection between sorting behaviour and technical infrastructure has been explored and described in some articles, there is still a gap when using this knowledge to design waste sorting systems. Future research in this field would benefit from being multidisciplinary and from using complementary methods, so that holistic solutions for material recirculation can be identified. It would be beneficial to actively involve users when developing sorting infrastructures, to be sure to provide a waste management system that will be properly used by them.

The new norms of food waste at the curb: Evidence-based policy tools to address benefits and barriers

Cities around the world are under increasing political pressure to develop organics collection programs (OCP) to curb the flow of food waste into landfills, reduce the associated greenhouse gases, and generate compost or biogas. While OCPs tend to focus on infrastructure, they often overlook the linchpin role that household behavior change plays in the success of OCPs. The current research used a longitudinal field experiment (n=370) to test both the effectiveness of a new curbside OCP and new social innovations intended to stimulate pro-environmental changes in household behavior. The findings suggest greater participation levels occur by implementing both new supportive infrastructure (i.e., curbside carts and collection services), and innovations that target the social aspects of waste (i.e., communicating social norms of separation). The data also provide an opportunity to test new model for predicting the most efficacious behavior-change interventions based on population profiles. The results provide some support for the model; reducing barriers (i.e., curbside carts and collection) tends to help all population profiles, but norm communication increases participation more for the hypothesized profile than for other sub-groups.

Evaluating opinions, behaviours and motivations of the users of a MSW separate collection centre in the town of Baronissi, Southern Italy

This paper presents the results of a survey regarding customer satisfaction as well as other aspects relating to the frequency and motivations of citizens going to a separate collection centre (SCC) for recyclables in a Southern Italian town. The study was carried out in 2015 to verify whether there were significant changes in the behaviours and opinions of the SCC's users, who had been interviewed in 2013, in the light of the change of the local administration. The majority of the respondents (60.4%) coupled going to the SCC with other tasks, with 58.6% of them going to a supermarket. Therefore, future SCCs should localized near shopping centres (it would be preferable to have small and numerous SCCs). Chi-square and Fisher's exact tests showed how SCC's users of the town under study behaved as a community. The percentage of respondents that declared to 'agree' or 'strongly agree' with the idea that only putrescibles and residue could be collected at their home, with all the other materials being collected at the SCC, increased from 56.6%, in 2013, up to 59.0%, in 2015. The percentage of respondents that declared going to the SCC due to environmental motivations was unanimous. Moreover, the saving of money for the community became the second preferred option, with a significant improvement (from 65.6%, in 2013, up to 93.2%, in 2015). Therefore, the community's interests over the individual's were privileged. The SCC's users confirmed their attention to environmental issues even though the local administration changed. It is probable that this could be the result of maintaining high standard of service as well as a good job in terms of communication, continuous involvment of citizens and the adoption of good environmental practices.

Characterizing Urban Household Waste Generation and Metabolism Considering Community Stratification in a Rapid Urbanizing Area of China

The relationship between social stratification and municipal solid waste generation remains uncertain under current rapid urbanization. Based on a multi-object spatial sampling technique, we selected 191 households in a rapidly urbanizing area of Xiamen, China. The selected communities were classified into three types: work-unit, transitional, and commercial communities in the context of housing policy reform in China. Field survey data were used to characterize household waste generation patterns considering community stratification. Our results revealed a disparity in waste generation profiles among different households. The three community types differed with respect to family income, living area, religious affiliation, and homeowner occupation. Income, family structure, and lifestyle caused significant differences in waste generation among work-unit, transitional, and commercial communities, respectively. Urban waste generation patterns are expected to evolve due to accelerating urbanization and associated community transition. A multi-scale integrated analysis of societal and ecosystem metabolism approach was applied to waste metabolism linking it to particular socioeconomic conditions that influence material flows and their evolution. Waste metabolism, both pace and density, was highest for family structure driven patterns, followed by lifestyle and income driven. The results will guide community-specific management policies in rapidly urbanizing areas.

Analyzing the success of the volume-based waste fee system in South Korea

For more than a decade, South Korea has been ranked first among the OECD (Organization for Economic Cooperation and Development) members in their municipal solid waste (MSW) recycling rate. One of the major contributing factors for its outstanding MSW recycling performance is the volume-based waste fee (VWF) system implemented in 1995. Despite the perceived success of VWF, there has been few research conducted that has sought to demonstrate the success of the policy in an empirical manner. Research conducted currently on VWF in South Korea tends to have limitations in empirical approaches and identifying the intervention effect of VWF on recycling performance. This study attempts to empirically test whether the adoption of VWF positively affected recycling performance in Korea over time. The findings suggest that although there was a dramatic increase of the recycling rate with the introduction of VWF in 1995, Korea's MSW recycling performance settled back again and showed the constant pace after the intervention. No significant differences in recycling rate were found between before and after 1995 period. In conclusion, implications and suggestions for both research and practice are proposed.

Methodology to design a municipal solid waste generation and composition map: a case study

The municipal solid waste (MSW) management is an important task that local governments as well as private companies must take into account to protect human health, the environment and to preserve natural resources. To design an adequate MSW management plan the first step consists in defining the waste generation and composition patterns of the town. As these patterns depend on several socio-economic factors it is advisable to organize them previously. Moreover, the waste generation and composition patterns may vary around the town and over the time. Generally, the data are not homogeneous around the city as the number of inhabitants is not constant nor it is the economic activity. Therefore, if all the information is showed in thematic maps, the final waste management decisions can be made more efficiently. The main aim of this paper is to present a structured methodology that allows local authorities or private companies who deal with MSW to design its own MSW management plan depending on the available data. According to these data, this paper proposes two ways of action: a direct way when detailed data are available and an indirect way when there is a lack of data and it is necessary to take into account bibliographic data. In any case, the amount of information needed is considerable. This paper combines the planning methodology with the Geographic Information Systems to present the final results in thematic maps that make easier to interpret them. The proposed methodology is a previous useful tool to organize the MSW collection routes including the selective collection. To verify the methodology it has been successfully applied to a Spanish town.

Attitude towards the incorporation of the selective collection of biowaste in a municipal solid waste management system. A case study

European waste legislation has been encouraging for years the incorporation of selective collection systems for the biowaste fraction. European countries are therefore incorporating it into their current municipal solid waste management (MSWM) systems. However, this incorporation involves changes in the current waste management habits of households. In this paper, the attitude of the public towards the incorporation of selective collection of biowaste into an existing MSWM system in a Spanish municipality is analysed. A semi-structured telephone interview was used to obtain information regarding aspects such as: level of participation in current waste collection systems, willingness to participate in selective collection of biowaste, reasons and barriers that affect participation, willingness to pay for the incorporation of the selective collection of biowaste and the socioeconomic characteristics of citizens who are willing to participate and pay for selective collection of biowaste. The results showed that approximately 81% of the respondents were willing to participate in selective collection of biowaste. This percentage would increase until 89% if the Town Council provided specific waste bins and bags, since the main barrier to participate in the new selective collection system is the need to use specific waste bin and bags for the separation of biowaste. A logit response model was applied to estimate the average willingness to pay, obtaining an estimated mean of 7.5% on top of the current waste management annual tax. The relationship of willingness to participate and willingness to pay for the implementation of this new selective collection with the socioeconomic variables (age, gender, size of the household, work, education and income) was analysed. Chi-square independence tests and binary logistic regression was used for willingness to participate, not being obtained any significant relationship. Chi-square independence tests, ordinal logistic regression and ordinary linear regression was applied for willingness to pay, obtaining statistically significant relationship for most of the socioeconomic variables.

Quantitative assessments of municipal waste management systems: using different indicators to compare and rank programs in New York State

The primary objective of waste management technologies and policies in the United States is to reduce the harmful environmental impacts of waste, particularly those relating to energy consumption and climate change. Performance indicators are frequently used to evaluate the environmental quality of municipal waste systems, as well as to compare and rank programs relative to each other in terms of environmental performance. However, there currently is no consensus on the best indicator for performing these environmental evaluations. The purpose of this study is to examine the common performance indicators used to assess the environmental benefits of municipal waste systems to determine if there is agreement between them regarding which system performs best environmentally. Focus is placed on how indicator selection influences comparisons between municipal waste management programs and subsequent system rankings. The waste systems of ten municipalities in the state of New York, USA, were evaluated using each common performance indicator and Spearman correlations were calculated to see if there was a significant association between system rank orderings. Analyses showed that rank orders of waste systems differ substantially when different indicators are used. Therefore, comparative system assessments based on indicators should be considered carefully, especially those intended to gauge environmental quality. Insight was also gained into specific factors which may lead to one system achieving higher rankings than another. However, despite the insufficiencies of indicators for comparative quality assessments, they do provide important information for waste managers and they can assist in evaluating internal programmatic performance and progress. To enhance these types of assessments, a framework for scoring indicators based on criteria that evaluate their utility and value for system evaluations was developed. This framework was used to construct an improved model for waste system performance assessments.

The effectiveness of recycling policy options: waste diversion or just diversions?

Recycling is becoming ever more important as waste generation rates increase globally. Policy-makers must decide which recycling practices to implement from the host of options at their disposal to best divert waste from landfill. This study strived to determine the most important characteristics in recycling programs that were associated with higher material recovery rates, including bag limits, user pay programs, the number of materials collected, curbside collection frequency, promotion and education (P&E) activities, Best Practice principles, and the type of recycling collection stream. Data collected from 223 recycling programs in Ontario during 2005-2010 were used to perform multiple regression analyses. The findings of this study suggest that attributes of convenience are more important to encourage recycling than those that penalize disposal, thus providing important implications for waste policy-makers, both in Ontario and in other jurisdictions.

Development and application of a multiple linear regression model to consider the impact of weekly waste container capacity on the yield from kerbside recycling programmes in Scotland

This article describes the development and application of a multiple linear regression model to identify how the key elements of waste and recycling infrastructure, namely container capacity and frequency of collection, affect the yield from municipal kerbside recycling programmes. The overall aim of the research was to gain an understanding of the factors affecting the yield from municipal kerbside recycling programmes in Scotland with an underlying objective to evaluate the efficacy of the model as a decision-support tool for informing the design of kerbside recycling programmes. The study isolates the principal kerbside collection service offered by all 32 councils across Scotland, eliminating those recycling programmes associated with flatted properties or multi-occupancies. The results of the regression analysis model have identified three principal factors which explain 80% of the variability in the average yield of the principal dry recyclate services: weekly residual waste capacity, number of materials collected and the weekly recycling capacity. The use of the model has been evaluated and recommendations made on ongoing methodological development and the use of the results in informing the design of kerbside recycling programmes. We hope that the research can provide insights for the further development of methods to optimise the design and operation of kerbside recycling programmes.

The impact of alternate weekly collections on waste arisings

Residual waste is commonly collected separately from recyclable and organic materials. Different forms of collection and disposal are used internationally since regional or municipal authorities have to adapt to their own circumstances. Many authorities have adopted an alternate weekly collection (AWC) of residual waste and recyclables to force/encourage householders to recycle; however, the degree to which they achieve waste reduction has yet to be reliably quantified. This study reports on how the introduction of AWCs affects household waste arisings. The paper evaluates single and dual stream collection methods and compares their performance with the previous system. Household waste collection trials were conducted between March and June 2009 in England (Lichfield). The trials examined changes to frequency of collection, type of container issued, amounts of sorting required of residents, household participation and productivity levels. A survey of households was completed before any changes were implemented. The quantity of recyclates collected was examined for 2008/2009 and 2009/2010. The study showed that the AWC scheme positively impacted on recycling rates and household behaviour, with no adverse impacts on public participation, household waste arisings or the local environment. No public health problems were reported. Both trials saw an increase in the quantities of recyclates collected per household during the trial period compared to the same period of time in the previous year. The dual stream performed better than the single stream, collecting an average of 5.94 kg/hh/week compared to an average of 5.63 kg/hh/week. The single stream system showed a greater increase in the weight of material collected (0.53 kg/hh/week vs. 0.48 kg/hh/week). Participation and set-out rates showed an increase during the trial period. The single stream option (comingled materials in one container) outperformed the dual stream service. The reduction in costs and improved productivity were the principal reasons used for extending the trial and making changes to the district's waste collections. The study clearly demonstrates the benefits of local authorities and universities collaborating and identifies practical logistical and operational issues that need to be anticipated.

Sustaining the environment through recycling: an empirical study

This paper examines the determinants of recycling behaviour among 200 university students from the perspective of the theory of planned behaviour (TPB). Data was analysed using Structural Equation Modelling technique. Findings indicate that environmental awareness was significantly related to attitude towards recycling, whilst attitude and social norms had significant impact on recycling behaviour. However, convenience and cost of recycling were not significant reasons for recycling. The study has enhanced the understanding of the determinants of recycling behaviour and has implications for schools and governmental agencies in educating and encouraging positive recycling behaviour. It also confirms the appropriateness of the TPB in examining studies of this nature. Further suggestions for future research are offered.