2.2.2 Waste quantities and types
A municipality must determine the quantities and the types of waste generated in its area of jurisdiction. This involves establishing the current quantities of waste generated, recycled, treated and disposed of. Waste quantities are usually measured by mass (kilograms or tons). This information is needed for:
- Ensuring adequate planning of resources to deliver waste management services;
- Rolling out of waste collection services to the unserviced area as prioritized by government;
- Establishing waste recycling initiatives i.e. buy-back centres which can have positive impacts in the reduction of the amount of recyclables going to landfill, and the establishment of SMME's in waste management which can promote entrepreneurship amongst residents;
- Provision of a certain number of waste receptacles and the establishment of collection needs i.e. how many skips should be provided in communal areas such as shopping centres, clinics and other public areas such as sport clubs; and for implementing separation at source initiatives,
- Ensuring that the municipality procures the correct types of vehicles as well as budgets for the correct number of vehicles that will be required to effectively deliver the service; and
- Making projections of future waste quantities in order to ensure that provision is made for future waste services delivery and the expansion of infrastructure to deliver the service i.e. the information will highlight if there is a need to establish new waste disposal facilities, transfer stations for faster and more effective collection rates.
This information can be collected from the following sources:
- Waste transporters - Municipalities, Private companies
- Waste managers - waste disposal facilities, treatment facilities
- IDP and municipal records
- Waste Information System: The Department of Environmental Affairs (DEA) and some Provinces (i.e. Gauteng and Western Cape) have developed waste information systems (WIS) which can provide valuable information on waste quantities and types.
(a) Waste information collection methods:
A situation analysis must include waste types and quantities of waste generated in a particular area. This information can be collected using the following methods.
Option1: Weighbridge
A municipality can make use of a weighbridge to collect and record the types and quantities of waste entering its waste disposal facility. This information is also required for reporting on the South African Waste Information System (SAWIS).
Using a weighbridge a municipality must record the amounts of waste entering its waste disposal facility, by weighing the vehicles at the point of entry and again on the way out. The difference in the mass of the vehicle between the 'in' and 'out' provides the mass of the waste. A weighbridge operator is required to correctly identify the types of waste disposed of. The data is captured using weighbridge software programmed with spreadsheet software such as Microsoft Excel or a customized weighbridge software that can simultaneously provide billing information based on the type of waste and the size of the vehicle.
Option 2: Without a weighbridge
Making use of the vehicle capacity and the waste densities template (a volume density estimation system)
In instances where a municipality does not have a weighbridge, it can make use of templates that were developed by DEA which are attached hereto as Annexure A and B. These provide guidance on how waste quantities can be estimated for the different waste streams. Annexure A provides a list of typical vehicles used to dispose of waste in waste disposal facilities. This template makes use of estimations (by mass) that have been made based on the size of the vehicles measured in m3. Annexure B contains possible pre-calculated and estimated density values which are based on the type of vehicle carrying a particular pre-classified waste type.
Waste mass estimation system uses a formula that requires waste volume, waste density and waste loading to determine the mass entering a waste disposal facility.
Example of how to calculate waste quantities using commercial/ industrial waste type/s
Formula: waste mass (kg) =vehicle volume (m3) x load/s x waste density (kg/ m3)
If for an example a vehicle has capacity of 10 m3; and the load is 2, with a waste density of 500 m3 the calculations would be as follows:
10 m3x 2 x 500 (kg/ m3) =10 000kg
The waste mass would then be 10 000kg
The capturing of the daily waste data can be recorded as shown in Table 5.
Table 5: An example of a daily waste data collection template
| Name of Landfill: Municipality X | ||||
|---|---|---|---|---|
| Date: 06/12/2011 | ||||
| Client | Vehicle registration no. | Vehicle capacity in m3 | Type of waste | Load |
| B Kumalo | BN 890 GP | 20 | Garden (greens) | 1 |
| R Naidoo | VW 1232 GP | 30 | Building | 1 |
| Sibanye recycling group | BC 682 GP | 50 | Tyres | 2 |
| V James | RT 782 GP | 10 | Building/garden mix | 1 |
On a monthly basis a municipality must compile a summary of the quantities of waste received and should submit this information to the South Africa Waste Information Centre (SAWIC). DEA has developed data capture forms which comprise of a landfill monthly data capture form as well as a landfill annual data summary form. Using the daily waste data collection form, municipalities are required to enter the information from the daily data capture form into a monthly data form in order to transfer the handwritten data into a spreadsheet. The table below provides an example of how the information is to be captured on a monthly data capture form: NB! This form has already been developed and it is available on SAWIC.
Table 6: An example of a monthly data capture form
Option 3: Sampling or conducting a waste stream analysis at a household/Ward level
Waste stream analysis or a waste audit can be conducted by selecting a representative sample of an area which should at least comprise of 30 %8 of the total sample area. In residential areas, these could be households from different Wards in order to ensure inclusivity and representation. Once that is known, the participating households can then be provided with receptacles and these could be different coloured plastic bags such as a black bag for mixed waste and a clear bag for recyclables. The participating households could also be provided with instructions/ training on the objectives of the study, what is required of them and how the audit will be carried out.
As an example, this could entail explaining to them the different types of commonly found domestic waste streams i.e. Glass, plastic, paper, cardboard, cans and garden waste etc. The participating residents can then be advised to separate their recyclables waste from non-recyclable/mixed waste, if the objective is to also measure the amount of recyclables generated in that area. Once collected, this should be weighed separately in order to gauge the mass of both recyclable waste and non-recyclables. A hand-held scale can be utilised for this purpose wherein the assessors (people employed to carry out the audit) will on the waste collection days or once a week depending on the agreed terms for the study; will individually weigh the waste in order to determine the amount of both recyclables generated in that particular area as well as the weight of non-recyclables.
After obtaining the figures from the participating households/Wards one is then able to extrapolate or estimate the amount of waste that is generated in that particular municipality. This can be done by adding the amounts of recyclables generated in all the areas, and then determine the average recyclables generated as well as by adding up mixed waste to determine their average. The recyclables could even be added up according to the various waste streams i.e. paper, glass, tin, cardboard etc. As illustrated below:
The different waste streams that were predominantly found in this particular area were as follows.
In Ward X, the waste composition and the amount of waste generated for both mixed and recyclable waste was as follows:
Table 7: Summary of waste recording for ward x
| Waste type/streams | Waste generated per week (kg) | Total percentages |
|---|---|---|
| Organic waste | 120 | 44.5% |
| Cans | 60 | 22.2% |
| Paper | 25 | 9.2% |
| Glass | 35 | 12.9% |
| Plastic | 30 | 11.2% |
| Total | 270 | 100% |
An assessor would have to record the types and amounts of waste generated in their study area for a given period of time and would need to write a summary of their findings. In area X the bulk of the waste comprised of organic waste (this included garden waste as well as vegetable peels from the kitchen) which came to 44.5% and from the recycling receptacles, cans were the majority at 22.2% followed by glass at 12.9% and then plastic at 11.2% with paper only making about 9.2% as illustrated above).
The same exercise can be performed for all the households of the different Wards that formed part of the sample size/area and this could even include business areas in order to get a bigger picture of how much waste is generated in that area apart from residential waste.
In order to get a visual description of how much waste is generated in the study area a table or a graph depicting all the different households/Wards that participated in the study could be generated and information from all the surveyed areas could be entered side by side in order to see which of the area/s or Wards in the study area generated the bulk of the waste and what waste streams were the majority.
A waste stream analysis has other benefits such as:
- It will indicate the potential for the establishment of a buy-back centre or the establishment of a Materials recovery facility (MRF).
- Will determine the current waste practices i.e. whether there is recycling taking place or illegal dumping.
Once the waste analysis results are known, they will assist in improving the current state of affairs with regards to waste management i.e. provision of waste management receptacles, establishment of separation at source programmes and recycling initiatives.
(b) Reporting to SAWIS
The Department has developed waste information regulations in terms of section 69(1) (y) and (ee) of the Waste Act that incorporated waste categorisation in order to regulate the collection and reporting of waste data and information to the SAWIS. The following table provides information on the categories/types of waste that should be reported to the SAWIS.
Table 8: General waste types categorisation
| Level 1 | Level 2 - Major Waste Type | Level 3 - Specific Waste Type | ||
| No | Name | No | Name | |
| GW 01 | Municipal waste | 01 | ||
| GW10 | Commercial and industrial waste | 01 | ||
| GW13 | Brine | 01 | ||
| GW14 | Fly ash and dust from miscellaneous filter sources | 01 | ||
| GW15 | Bottom ash | 01 | ||
| GW16 | Slag | 01 | ||
| 02 | Non-ferrous metal slag | |||
| 03 | Other | |||
| GW17 | Mineral waste | 01 | Foundry sand | |
| 02 | Refractory waste | |||
| 03 | Other | |||
| GW18 | Waste of Electric and Electronic Equipment (WEEE) | 01 | Large Household Appliances | |
| 02 | Small Household Appliances | |||
| 03 | Office, information & Communication Equipment | |||
| 04 | Entertainment & Consumer Electronics and toys, leisure, sports & recreational equipment and automatic issuing machines | |||
| 05 | Lighting equipment | |||
| 06 | Electric and Electronic tools | |||
| 07 | Security & health care equipment | |||
| 08 | Mixed WEEE | |||
| GW20 | Organic waste | 01 | Garden waste | |
| 02 | Food waste | |||
| GW21 | Sewage sludge | 01 | Sewage sludge | |
| GW30 | Construction and demolition waste | 01 | ||
| GW50 | Paper | 01 | Newsprint and magazines | |
| 02 | Brown grades | |||
| 03 | White grades | |||
| 04 | Mixed grades | |||
| GW51 | Plastic | 01 | PET | |
| 02 | Others | |||
| GW52 | Glass | 01 | ||
| GW53 | Metals | 01 | Ferrous metal | |
| 02 | Non-ferrous metal | |||
| GW54 | Tyres | 01 | ||
| GW99 | Other | 01 | ||
Once the information on the types and quantities of waste generated in a particular municipality has been collected the municipality can either enter its information directly to SAWIC at www.sawic.org.za or it could manually provide its information to a Provincial waste information officer who will then enter the information on its behalf to SAWIC.
- Taken from StatsSA: general guide for sampling, this implies that in a given area the sample size should at least be 30% of the total population