Problem associated with composting household organic waste, such as time
consuming and limited space, have received increasing attention during the
last few years. As suburban city, Depok generates about 3480 m3 of municipal
solid wastes per day comprised of 68,25% organics and 31,75% of inorganic.
During the last five years, home made composting with bioactivator was
introduced by local governments to reduce amount of municipal wastes going
into landfill. These traditional bioactivators were used to accelerate
decomposing process but their impact has never been studied before. The
objective of this study were to assess the seeding effect on home made
composting by inoculating a mixture of organics household wastes with
bioactivator. Among six bioactivators used, three were traditional
bioactivators that usually added by local people to their compost piles while
the others purchased from the market. The rates of decomposition were
measured in 100 days with no significant effects observed in volume reduction
using any of bioactivators. In general, 50-56 % volume reductions occurred in
the first 60 days of composting process with no major volume reductions in
the last 40 days. In addition there were 81-85% mass loss during composting.
At the end of 100 days of composting process, all of the seven investigated
treatments have the same volume reduction and mass loss. No fecal coliform
destructions occur during the process since the maximum temperatures is
45oC.The results indicate that bioactivator application in municipal waste
composting is ineffective in accelerating the process.

Keywords: bioactivator, household organic waste, compost, mass loss,
volume reduction.