chapter 4: temperature inside the landfill

educing distance between the sensors and injection More likely possibilities may be the
presence of preferential pathways and inefficiency of the injection system.
The increase in average temperature at all the three depths was observed to follow a
linear curve while leachate was injected and the rate of increase was approximately 5 0 C/year.
The decreasing trend in temperature after Day 1100 at the shallow sensors suggests a decline in
biological activity due to lack of moisture after injection stopped and liquid drained to lower
depths (confirmed by samples extracted recently). It also entails that the deeper layers are more
insulated and wetter than the upper layers of the waste in the landfill.
The results from the research suggest that temperature sensors which use simple,
inexpensive technology may be suitable for detecting moisture movement and even estimating
injection device efficiency. From the comparison between temperature and moisture sensors in
the research, it can be concluded that moisture sensors perform marginally better in terms of
performance, however these have associated costs (capital and operational), and operational
difficulties. Further research is needed to support the approach and establish temperature sensors
as a means to track moisture arrival under conditions that optimize their use for this purpose.
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