Document ID: chunk:federal_register_of_legislation:F2024C00833:reg:10:p10
Version: federal_register_of_legislation:F2024C00833
Segment Type: reg
Provision Reference: reg 10 (pt 10/15)
Character Range: 698172–700907

expert performs the calculation mentioned in paragraph (a); or
 (c) take all reasonable steps to ensure that the independent expert works out the minimum number of flux boxes for the area by using the following formula:

where:
Z is the size of the area within the representative zone that has high methane emissions, measured in square metres.
 (10) In this section:
low methane emissions means methane emissions that the results of a scan performed in accordance with this section indicate are equal to or less than 50 parts per million.
intermediate methane emissions means emissions that the results of a scan performed in accordance with this section indicate are greater than 50 parts per million and equal to or less than 100 parts per million.
elevated methane emissions means methane emissions that the results of a scan performed in accordance with this section indicate are greater than 100 parts per million and less than 500 parts per million.
high methane emissions means methane emissions that the results of a scan performed in accordance with this section indicate are equal to or greater than 500 parts per million.

5.17H  Flux box measurements
 (1) After the flux boxes have been installed in the representative zone, the operator must:
 (a) measure the flow of methane in each flux box and arrange for an independent expert to certify, in writing, that the measurements are accurate and were correctly measured; or
 (b) arrange for an independent expert to take the measurements.
Note: AS/NZS 4323.4—2009 and the publication entitled Guidance on monitoring landfill gas surface emissions published by the Environment Agency of the United Kingdom in September 2004 contain guidance on how to take measurements in flux boxes.
 (2) The flow of methane from each flux box must be calculated in accordance with the following formula:

where:
Q is the flow density of the gas in the flux box, measured in milligrams of methane per square metre per second.
V is the volume of the flux box, measured in cubic metres.
  is the rate of change of gas concentration in the flux boxes over time, measured in milligrams per cubic metre per second.

A is the area covered by the flux box, measured in square metres.
 (3) The total gas flow rate for the representative zone is to be obtained by using geospatial interpolation techniques.
 (4) The amount of methane generated, but not collected, in the representative zone must be estimated by dividing the total gas flow rate obtained in accordance with subsection (3) by:

where:
OF is the oxidation factor mentioned in subsection 5.15(1).
 (5) The measurement of methane obtained under the formula in subsection (2) must be converted from milligrams of methane per square