ABSTRACT
The reduction in the generation and disposal of waste has become an urgent priority in South Africa as evidenced in the promulgated National Environmental Management: Waste Act (RSA, 2008). In South Africa, the most common waste management method is by landfill. Most of these landfills do not comply with the standards for modern landfills, resulting in a negative impact on the environment. Approximately one third of all municipal waste landfilled is organic waste, which is biodegradable and can be converted to compost. Based on a feasibility assessment of establishing composting facilities on municipal landfill sites, this study applied the Draft Norms and Standards for Organic Waste Composting to facilities using a set of criteria. The draft Norms and Standards for Organic Waste Composting were developed to give effect to the National Organic Waste Composting Strategy aimed at beneficiating organic waste by promoting composting as one treatment option. The results show that the criteria are generally compliant with the suggested norms and standards. The areas that are lacking are of a legal nature, specifically with regard to monitoring of the operations. It was found that the draft Norms and Standards for Organic Waste Composting address legal, environmental, social and operational issues to protect the environment and the surrounding landowners.
Keywords: composting, organic waste, waste minimisation, landfill sites, criteria for composting facilities
INTRODUCTION
Background
In South Africa, landfill sites are under pressure due to the increased volumes of waste generated by a growing population and economy (DEA, 2012a). The National Waste Management Strategy (NWMS) was developed to improve waste management and specifically promote waste minimisation in all its forms (DEA, 2012a). The green waste fraction of the municipal waste disposed of in landfill sites has a cumulative negative effect on the environment due to the high nutrient content and the ability to decompose rapidly, in the process releasing harmful greenhouse gases and leachate (Botkin & Keller, 2007; City of Illinois Extension, 2016; Diaz et al., 2007).
Organic waste is a renewable resource which can be converted into compost, a humus-like substance in the pre-treatment of municipal solid waste (MSW), to produce a soil amendment that can enhance physical, chemical and biological soil properties (Diaz et al., 1993; Pan et al., 2012).
Policy environment
In South Africa, the responsibility for managing MSW falls to local governments, as assigned by the Constitution of South Africa (RSA, 1996). The National Environmental Management: Waste Act (Section 11(4)) (RSA, 2009), requires local municipalities to develop integrated waste management plans, which, after approval by the Member of the Executive Council (MEC), must be incorporated into the Municipal Integrated Development Plan as contemplated in Chapter 5 of the Municipal Systems Act (RSA, 2000). Municipalities are therefore legally compelled to manage the waste generated within their boundaries according to legislation and have the authority to determine the method of disposal. The need for application of the waste hierarchy, including waste minimisation, reuse and recycling, has become essential to reduce waste disposal to landfill sites in an attempt to prolong the lifespan of the existing landfill sites which are rapidly filling up (CSIR, 2011; DEA, 2012a). To give effect to the National Waste Management Strategy (NWMS) (DEA, 2012a), the Department of Environmental Affairs (DEA) developed the National Organic Waste Composting Strategy (NOWCS) (DEA, 2013a) specifically aimed at addressing the green fraction of MSW.
The aim of this study is to present a solution to waste minimisation through the establishment of composting facilities, in line with current legislation, on landfill sites. There is no evidence in literature that this is being done either nationally or internationally.
National Organic Waste Composting Strategy
In an attempt to regulate general waste, section 20 of the Environmental Conservation Act (ECA), (RSA, 1989) was applicable for the permit application to run a composting operation. Thereafter, the Environmental Impact Assessment (EIA) regulations of 2006 (GN 386, 1(o)) regulating handling of general waste of more than 20 tonnes per day. This regulation was repealed and replaced by Category A of GN 718, issued on 3 July 2009 in terms of the National Environmental Management: Waste Act (RSA, 2008) and required that a basic assessment report be submitted for review with the aim to obtain a waste management licence (WML) (DEA, 2009). Currently, GN 921 of 29 November 2013 is the applicable legislation for the application to treat general waste, therefore also green waste (DEA, 2013b).
To promote the establishment of composting facilities and thus prevent green waste being landfilled and to alleviate legislative requirements of applying for a WML, the DEA initiated the compilation of a strategy for composting of green waste (DEA, 2013a): “This project is to strategise the potential of composting as a method to beneficiate organic waste, as one of a basket of options to help divert organics from landfill disposal”. The National Environmental Management: Waste Act: National Norms and Standards for Organic Waste Composting (draft report) (hereafter referred to as N&S) was consequently published on 7 February 2013, suggesting minimum requirements for the operation of a composting facility and is currently awaiting promulgation.
The limit is set for a facility with the capacity to process in excess of 10 tonnes but less than 100 tonnes of compostable organic waste per day. The same limit as in listed activity A(6) of GN 921 is used, which must be adapted (to exclude organic waste) before the N&S for composting can be effected (Gower-Jackson, 2015). In terms of composting facilities on landfill sites, no additional legal requirements other than compliance with the N&S will be discussed.
Municipal response
It is common practice to have drop-off points for recyclables, including green waste at garden centres (also known as transfer stations) from where the waste is transported to composting facilities (Furter, 2004; Pikitup, 2007).
Since April 2001, Cape Town has diverted the green waste from landfill sites by creating collection points at conveniently located garden sites (Furter, 2004). At 11 of the 17 council drop-off facilities, the incoming garden waste is collected and the volume is reduced to 25% through chipping. Through private partnerships, the green waste is collected from various facilities for composting, thereby creating savings for the municipality in terms of reduced transport costs and landfill airspace (Furter, 2004). The City of Tshwane Metropolitan Municipality (CTMM) has 10 garden sites for the convenience of the residents. From there, green waste is transported to the landfill site by the municipality (CTMM, 2015). The City of Johannesburg Metropolitan Municipality (CJMM) has 48 garden drop-off sites, one of which, the Panorama composting site in Roodepoort, received most of the green waste collected from the garden sites and converted it into compost, between 1994 and 2015 (Pikitup, 2016).
Composting facilities on landfills
The NOWCS (DEA, 2013a) mak...
