Some of the air pollution regulations in the United States are based on an
application of the National Ambient Air Quality Standards at the property line.
Agricultural operations such as cotton gins, feed mills, and cattle feed yards may be
inappropriately regulated by such regulations if the current methods of measuring and
predicting the concentrations of regulated pollutants are used. The regulated particulate
matter pollutants are those with aerodynamic equivalent diameters less than or equal to a
nominal 10 and 2.5 micrometers (PM10 and PM2.5) respectively.
The current Federal Reference Method PM10 and PM2.5 samplers exhibit oversampling
errors when sampling dusts with particle size distributions similar to those of
agricultural sources. These errors are due to the interaction of the performance
characteristics of the sampler with the particle size distribution of the dust being
sampled. The results of this work demonstrate the development of a new sampler that
may be used to accurately sample total suspended particulate (TSP) concentrations. The
particle size distribution of TSP samples can be obtained and used to more accurately
determine PM10 and PM2.5 concentrations. The results of this work indicate that accurate
measures of TSP can be taken on a low volume basis. This work also shows that the low
volume samplers provide advantages in maintaining more consistent sampling flow
rates, and more robust measurements of TSP concentrations in high dust concentrations.
The EPA approved dispersion model most commonly used to estimate
concentrations downwind from a stationary source is the Industrial Source Complex
Short Term version 3 (ISCST3). ISCST3 is known to over-predict downwind
concentrations from low level point sources. The results of this research show that the
magnitude of these errors could be as much as 250%. A new approach to correcting
these errors using the power law with P values as a function of stability class and
downwind distance is demonstrated. Correcting the results of ISCST3 using this new
approach results in an average estimated concentration reduction factor of 2.3.
| Identifer | oai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/3992 |
| Date | 16 August 2006 |
| Creators | Wanjura, John David |
| Contributors | Parnell, Calvin B |
| Publisher | Texas A&M University |
| Source Sets | Texas A and M University |
| Language | en_US |
| Detected Language | English |
| Type | Book, Thesis, Electronic Thesis, text |
| Format | 808983 bytes, electronic, application/pdf, born digital |
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