Optical Remote Sensing to Determine Strength of Nonpoint Sources: Duke Forest Validation Study (ESTCP #CP-0214)
Final technical rept.
ARCADIS GERAGHTY AND MILLER RESEARCH TRIANGLE PARK NC
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Currently there is no suitable standardized method for measuring non-point source emissions. Under EPA and DOE support, a new method of directly measuring area sources has been developed. This method, Radial Plume Mapping RPM, uses a scanning optical sensor, and asymmetrically placed array of reflectors, wind measurements, and optimization algorithms to calculate area source emissions from non-point sources using open-path Fourier Transform Infra-Red spectrometer OP-FTIR. Trace gases, nitrous oxide, ethylene and acetylene, propylene and propane, are released in a controlled manner and their locations of release are recorded. By radial scanning on a horizontal plane close to the ground and the location of the point releases are reconstructed. Area sources were simulated with soaker hoses laid out in H-shape configurations and by scanning beams in a vertical plane downwind from the sources, the fluxes were computed and compared to the known actual release rates. The results show that the source locations were reconstructed successfully to within 10 of the diagonal length of the investigated area using the horizontal RPM and the calculated mass flux agreed with the known release rates to within a few percent, under stable experimental conditions.
- Numerical Mathematics
- Acoustic Detection and Detectors
- Target Direction, Range and Position Finding