Development of EPA OTM 10 for Landfill Applications

Abstract

In 2006, the U.S. Environmental Protection Agency posted a new test method on its website called Other Test Method 10 (OTM 10) which describes direct measurement of pollutant mass emission flux from area sources using ground-based optical remote sensing. The method has validated application to relatively small bounded area sources but additional guidance is needed for large area sources, such as landfills, where the emission zone can exceed the size of optical configuration leading to difficulties in relating measured fluxes to emissions per unit area. This paper presents the findings of a series of tracer-release experiments designed to improve the understanding of OTM 10 in landfill applications. OTM 10 plume capture efficiency data acquired at a variety of landfill sites under a range of meteorological conditions and measurement configurations are presented. Experiments indicate an overall capture efficiency factor of 0.81 with a standard deviation of 0.33. Lower capture efficiencies from side slope releases are noted (0.69). The combined data set is analyzed for factors influencing capture efficiency. A multiple linear regression is used to model the capture efficiency as a function of primary parameters including distance of the tracer release from the observing plane and wind speed. A simplified model based on the regression analysis is described and its use for approximating the area contributing to flux is presented.