Assessing Accuracy of Tracer Dilution Measurements of Methane Emissions from Landfills with Wind Modeling - Extension

Investigators: University of Delaware & University of California, Berkley

Start Date:
October 2016

Award Amount:
$93,069

The solid waste industry, in collaboration with the U.S. EPA, have been evaluating the Tracer Dilution Method (TDM) over the last six years to measure methane emissions at landfills with different climates, in different operational stages, and with or without landfill gas collection systems. These data provide valuable insight into methane emissions and represent a significant financial investment. The TDM, however, has not yet been verified with known emissions from an actual landfill. Further, some uncertainty in TDM data still needs further evaluation, since data are typically collected during the day and require particular wind conditions. This work addresses these limitations by applying a land-atmosphere model to a southeastern US landfill where over 440 independent measurements were performed over three years. These measurements span seasonal variations at the site (making it the most well-sampled site for whole landfill emissions in the U.S.). The main objectives of this research are:

  1. Develop a three dimensional land-atmosphere model for the southeastern US landfill, validating the model with observed tracer gas data in the field
  2. Use this new model to simulate CH4 emissions and estimate measurement error for prior daytime field measurement campaigns at this site
  3. Use the model to estimate emissions at night and during periods when field measurements were not performed
  4. From this modeling work assess the representativeness of CH4 emission data from limited measurements for calculating year-round CH4 emissions for any given landfill