Quantifying Uncontrolled Landfill Gas Emissions from Two Florida ...

3.2.2 Bioreactor Cell
3.2.2.1 February 23
ORS measurements were collected in the bioreactor cell on February 23. A schematic of the
ORS measurement configuration from this cell can be found in Figure 2-6. Figure 3-6 presents a
summary of the actual measurement configurations used in the cell, as well as the measurement
results. The figure depicts the average calculated methane flux values along each VRPM
measurement plane. The blue arrow depicts the prevailing wind values during the time of the
measurements.
Figure 3-6 Summary of ORS measurements conducted on Feb. 23 in bioreactor cell of Site
#2.
The figure shows that the prevailing winds were from the northeast during the time of the
measurements. Based on the prevailing wind direction, the northern and eastern VRPM planes
are located upwind of the actual landfill cell, so flux values measured along these VRPM planes
represent methane emissions from the northern and eastern slopes of the cell (by convention of
the measurement method, flux values from measurement planes located upwind of the landfill
cell are shown as negative values). The VRPM planes located along the southern and western
boundaries of the cell are downwind of the landfill cell (by convention, flux values from
measurement planes located downwind of the landfill cell are shown as positive values).
The methane flux values measured along the northern, eastern, southern, and western VRPM
measurement planes were 3.7, 0.69, 5.0, and 5.1 grams per second, respectively. The difference
between the sum of the fluxes measured along the southern and western planes (10 g/s) and the
northern and eastern planes (4.4 g/s), 5.6 grams per second, represents the calculated methane
flux value from the top of the landfill cell (defined as the flat surface area where instrumentation
was deployed). The sum of the flux values measured along the northern and eastern planes, 4.4
grams per second, represents the calculated methane flux value from the northern and eastern
slopes of the landfill cell.
Tables 3-24, 3-25, 3-26, and 3-27 present the calculated methane flux, measurement time,
prevailing wind speed, and prevailing wind direction during the time of the VRPM
3-28