Determining spatial and temporal change in household solid waste composition within Stellenbosch local municipality

Thesis (MPhil)--Stellenbosch University, 2020.

ENGLISH ABSTRACT: The quantities in which solid waste is generated are continuously increasing throughout the world. If waste is not treated or disposed of in an appropriate manner, the consequences for societies and environments are likely to be extremely adverse, if not catastrophic. Consequently, effective management of household solid waste is crucial to ensuring the maintenance of clean and healthy living environments. As it is incumbent upon local authorities in South Africa to provide solid waste management services, they require accurate information pertaining to their waste streams to guide their waste management practices. It is widely recognised throughout the world that waste characterisation studies represent an optimal means of obtaining detailed data pertaining to waste streams. This thesis concerns the findings and a comparative analysis of two waste characterisation studies which were conducted in 2012 and 2017 in the Stellenbosch municipal area. The studies were concerned solely with the residual portion of household solid waste which is landfilled. While the fourteen areas were surveyed in the study of 2012 and samples were sorted into seven fractions, twenty-three areas were surveyed in the study of 2017 and some of the fractions which had been used in 2012 were further sub-divided to yield a total of eighteen fractions. Ten of the areas which were surveyed in 2017 were either similar to or overlapped with those which were surveyed in 2012. In each study, waste profiles were determined by both mass and uncompacted volume for each area. The respective findings from 2012 and 2017 were then compared to identify spatio-temporal changes and statistical analyses were performed to determine the significance of each change. Correlations were also determined between relevant socioeconomic parameters and the data which had been obtained pertaining to the waste streams of individual areas. Organic waste represented the predominant waste fraction by mass in all ten overlapping areas in the two characterisation studies, while the plastic wrap/packaging fraction was the largest by volume in all areas in both studies. The largest and most significant temporal changes from 2012 to 2017 were a very large increase by mass in the case of the plastic wrap/packaging fraction and by volume in that of the hard plastics fraction. The findings revealed that the high rates at which particular fractions of the waste stream were disposed of in low-income areas were skewed as a consequence of the separation at source programme not being implemented in the areas. Consequently, it is recommended that the implementation of the programme should be extended to all areas which fall under the jurisdiction of the Stellenbosch Local Municipality, in the form of a three-bag separation at source programme. Improved education and awareness concerning the waste crisis with which the municipality is faced at present is also equally crucial.

AFRIKAANSE OPSOMMING: Die hoeveelhede vaste afval wat gegenereer word, neem deurlopend wêreldwyd toe. As afval nie op 'n toepaslike manier hanteer of weggegooi word nie, sal die gevolge daarvan vir samelewings en die omgewing waarskynlik uiters nadelig wees, indien nie katastrofies nie. Gevolglik is effektiewe bestuur van vaste huishoudelike afval noodsaaklik om die instandhouding van 'n skoon en gesonde leefomgewing te verseker. Aangesien dit die plaaslike owerhede in Suid-Afrika se verantwoordelikheid is om dienste vir vaste afvalbestuur te lewer, benodig hulle akkurate inligting rakende hul afvalstrome om hul planne te beraam. Wêreldwyd word dit algemeen erken dat afval-ontledingsstudies 'n optimale manier is om gedetailleerde data rakende afvalstrome te bekom. Hierdie tesis handel oor die bevindings en 'n vergelykende analise van twee afval-ontledingsstudies wat in 2012 en 2017 in die Stellenbosch munisipale gebied uitgevoer is. Die studies het slegs betrekking op die gedeelte van die afvalstroom wat na die stortingsterrein toe gestuur word. Veertien areas was tydens die 2012 studie ondersoek en monsters in sewe fraksies sorteer. Drie-en-twintig areas was in 2017 ondersoek en monsters in dieselfde sewe fraksies sorteer en toe verder verdeel om 'n totaal van agtien fraksies te lewer. Tien van die gebiede wat in 2017 ondersoek is, het oorvleuel met die wat in 2012 ondersoek is. In albei studies is profiele vir elke gebied bepaal deur die massa en die onsaamgepersde volume van daardie area se afvalstroom te bepaal. Die onderskeie bevindings van 2012 en 2017 is daarna vergelyk om tyd-ruimtelike veranderinge te identifiseer en statistiese ontledings is uitgevoer om die belang van elke verandering te bepaal. Korrelasies is ook bepaal tussen relevante sosio-ekonomiese parameters en die gegewens wat verkry is met betrekking tot die afvalstrome van individuele gebiede. Organiese afval verteenwoordig die oorheersende afvalfraksie volgens massa in al tien oorvleuelende gebiede in albei ontledingsstudies, terwyl die plastiekomhulsel / verpakkingsfraksie die grootste volgens volume in al die gebiede in albei studies was. Die grootste en belangrikste tydelike veranderinge van 2012 tot 2017 was 'n baie groot toename in massa in die geval van die plastiekomhulsel / verpakkingsfraksie en volgens volume in dié van die harde plastiekfraksie. Die bevindings het aan die lig gebring dat hoë hoeveelhede van sekere fraksies van die afvalstroom was in lae-inkomstegebiede weggegooi. Dit was as gevolg van die herwinningsprogram wat nie in die gebiede geïmplementeer is nie. Gevolglik word dit aanbeveel dat die implementering van die herwinningsprogram uitgebrei moet word na alle gebiede wat onder die jurisdiksie van die Stellenbosch Plaaslike Munisipaliteit val, in die vorm van 'n drie-sak skeiding. Meer klem moet ook geplaas work op bewusmaking rakende die tekort aan lugspasie.

Masters