Abstract: A metering pipe is telescoped, at least partially, within a pipe through which gas flow rate is to be measured. Gas flow is routed through the metering pipe and is measured by means of pressure sensors monitoring gas pressure therein.

Abstract: A method for determining total landfill gas production capability and pollutant emission rates involves measuring gas pressure in a soil cover at various locations around the landfill. These measurements are preferably made successively and repeated. The tester determines an average gas pressure and its spatial uncertainty envelope and measures soil pneumatic permeabilities by taking soil samples, preferably at various locations. The soil is tested to determine viscous and inertial resistance coefficients to characterize permeability. The gas composition is determined preferably at each pressure measuring location, and the coefficients, gas pressure and composition measurements are used to calculate total gas emission.