chapter 4: temperature inside the landfill

The first column of Table 3-1 identifies the scenario. Column 2 of Table 3-1 verifies
whether there was an injection event or not. The third column shows whether there was a
response/ (temperature drop event) at the MTG sensor or not. The fourth column gives
information abut the response at the resistance sensor. Column 5 explains the possible causes of
the occurrence of injection and sensor responses for that scenario.
Scenario 1, 2, 3 and 4 indicate situations when there is an injection event according to the
injection records or indicated by temperature drop at the injection point. Scenario 1 supports the
hypothesis as the temperature is able to predict the moisture arrival. Scenario 2 refutes the thesis
as there is no response at the temperature sensor. The possible reason for Scenario 2 may be that
the injected liquid was heated while traveling through the landfill with enhanced biological
activity due to earlier moisture movement. Scenario 3 may have different explanations as neither
temperature and moisture sensors detected moisture arrival and is therefore neutral to the
hypothesis. The moisture sensor may already be saturated when the moisture arrived. Liquid,
while traveling through the heated waste, may warm and may not cause substantial drop in the
temperature at the temperature sensor. Other possible explanation may be that moisture did not
arrive at the MTG sensor at all because of channeling in the waste and preferential paths around
it. Scenario 4 supports the hypothesis as suggested by the response in temperature reading.
Scenario 5, 6 and 7 are related to situations when there was a response at a sensor without
an event at the injection well. Scenario 5 attributes this response to the liquid injected at a remote
injection well that traveled to the monitoring location and led to response in temperature as well
as moisture reading and thus it favors the hypothesis. Scenario 6 refutes the hypothesis as there is
no injection event and no detection by the moisture sensor but the temperature sensor showing a
substantial temperature drop. Hence the sensor may be malfunctioning. Scenario 7 refutes the
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