67. At least 4 times a year, at intervals spread evenly throughout the year, the operator of an engineered landfill must monitor or have the concentration of methane in the soil and inside the buildings and facilities monitored in order to ensure compliance with the requirements of section 60. The operator is, however, exempt from that monitoring requirement if the landfilled residual materials are not likely to generate methane.
The number and location on the site of the methane monitoring points are determined according to the geological and hydrogeological conditions and the siting features, subject to the following:
(1) the measurements in the soil must be taken at a minimum of 4 monitoring points distributed evenly around the disposal areas;
(2) if the disposal areas exceed 8 ha, a monitoring point must be added for each additional 8-ha portion of land or remaining portion of less than 8 ha.
The date, time, temperature and barometric pressure must be recorded every time a measurement is taken pursuant to the second paragraph.