Chemical and biological characterization of municipal solid waste at Chunga landfill for potential use as compost.

The Chunga landfill located in the northern part of Lusaka city receives on a daily basis
approximately 500 tonnes of comingled waste comprising mostly municipal solid waste
(MSW). The MSW has being accumulating over the years within the limited space at the
landfill without being recycled. Composting is one of the best methods of managing
MSW because of the useful end product called compost. The application of compost to
the soil has many benefits such as soil enrichment, fertility enhancement, and
improvement of the soil’s physical and chemical properties. The current study was
conducted to characterize MSW compost at Chunga Landfill for chemical and biological
parameters to assess its potential to be used as compost so as to free up some space for
the incoming MSW. The samples were taken from cell 2 where no fresh MSW was added
for one year. Parameters used to assess the quality of the MSW were pH, EC, C:N ratio,
OM, nitrogen, phosphorous, potassium, cadmium, lead, chromium, copper, nickel, zinc,
presence of Salmonella spp. E. coli, feacal coliforms and viable Ascaris ova. Results
indicated pH 7.94 ± 0.01, EC 6.46 ± 0.03 mS/cm, OM 6.76 ± 0.02 percent, C:N ratio
5.10, total nitrogen 0.77 ± 0.01 percent, phosphorous 0.53 ± 0.04 percent, potassium 0.88
± 0.03 percent, copper 156.8 ± 5.52 mg/kg, zinc 207.83 ± 18.60 mg/kg, cadmium 4.63 ±
0.94 mg/kg, chromium 60.7 ± 0.57 mg/kg, lead 109.58 ± 8.92 mg/kg, nickel 28.75 ± 0.49
mg/kg, feacal coliforms >1,100 MPN/g, E. coli >1,100 MPN/g, Salmonella not detected
per 25g and Ascaris was non-viable. Chemical characteristics with regard to pH, EC and
heavy metals were within the stipulated values for matured compost and FAO standards
while OM, biological characteristics and NPK were below. Therefore, the Chunga
Landfill MSW may be applied as compost on low value crops and as a soil conditioner.
It is recommended that the Chunga Landfill MSW compost must be sanitized to get rid
of E. coli and feacal coliforms, material to be segregated at source or at the disposal site
to boost OM and lower the heavy metal concentration, the chemical and biological
characteristics of Chunga Landfill MSW compost be monitored on a monthly basis for
one calendar year to check for variations in analytical data, a portion of the Chunga
landfill be dedicated where only the degradable organic material will be disposed and
Government to come up with chemical and biological guidelines on the utilization of
MSW as compost.
Keywords: MSW, compost, chemical, biological characteristics, Chunga Landfill