Quantifying Uncontrolled Landfill Gas Emissions from Two Florida ...

cell to the base. The following equation shows the calculation of the total surface area of the
slopes:
(180m *100m) + (160m *100m) + (52m * 100m) + (51m * 100m) = 44,300 m 2
In order to calculate the total methane emission factor from the control cell, a weighted average
calculation was used. According to the calculations above, the surface area of the slopes is
approximately 84 percent of the total surface area of the cell. The surface area of the top is
approximately 16 percent of the total surface area of the cell. The following details the
calculation of the weighted average measured methane emission factor from the control cell:
0.16 * 64 g/day/m 2 methane top of cell + 0.84 * 22 g/day/m 2 methane slopes =
29 g/day/m 2 methane control cell
This value is converted to kilograms of methane per day by multiplying by the total surface area
of the cell, and dividing by 1000 to yield a cell emissions value of 1,500 kg/day.
The total site methane emissions are found by adding the values of the total methane emissions
from the control and bioreactor cells.
Table 3-8 presents the results of these calculations for Site #1.
Table 3-8. Summary of total site methane emissions calculations from Site #1
Calculation Control Cell Bioreactor Cell
Total Surface Area of Top of Cell
2
8,800 m
2
13,500 m
Total Surface Area of Slopes
2
44,300 m
2
47,700 m
Methane Emission Factor of Top of Cell 64 g/day/m 2
40 g/day/m 2
Methane Emission Factor of Slopes 22 g/day/m 2 68 g/day/m 2
Total Methane Emission Factor of Cell
2
29 g/day/m
2
62 g/day/m
Total Cell Methane Emissions 1,500 kg/day 3,800 kg/day
Total Site Methane Emissions= 5,300 kg/day
Based on the calculations presented in Table 3-8, the total methane emissions from Site #1 are
estimated to be 5,300 kilograms per day. It should be noted that this estimated value is
extrapolated from a limited amount of flux data, and does not take into account diurnal or
seasonal trends in methane emissions.
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