The first step in waste characterization is pre-investigation.
1.1 BACKGROUND INFORMATION
General Description of the Area under Investigation
- The area, its location and surface area should be identified.
- The information includes identification of Geo political areas and all the waste management data available.
General Population Information
Population information includes:
- number of inhabitants
- number of households
- income level
- type and proportion of residential structure
Waste Management Information
- Waste management information deals with:
- Description of waste management system organization such as actors and their responsibilities
- Type of waste produced or collected e.g. mixed household waste or co collected household and commercial waste
- Description of waste containers that are in use such as household bins, communal bins and bins storage capacity
- Average number of people using bins
- Total bin volume, their spatial distribution in areas and bins collection intervals
- method of waste collection such as use of either open trucks or compactors, type of waste collected.
- Description of waste collection rounds/route
- Weighing data of Collection vehicles
- Waste disposal methods e.g. reuse, recycling, landfill, quantity of waste to be disposed off
Stratification is the statistical subdivision of parent population (e.g. waste coming from an area) to more homogeneous subgroups or populations (e.g. waste from residential area).
The changes in strata is small as compared to population changes. This results in:
High accuracy in results at given sample size
Stratification reduces the sample size to reach high accuracy results.
Stratification is not compulsory for waste analysis. But it has the benefit over accuracy of results and additional waste management information.
Following criteria's are seen while stratification:
- Residential structure
- Heating systems
- Bin size
- Holiday periods
- Availability of civic amenity sites
- Type of collection systems
- Level of Public awareness and education systems