Science Inventory

Emissions from prescribed burning of timber slash piles in Oregon.


Aurell, J., B. Gullett, D. Tabor, AND N. Yonker. Emissions from prescribed burning of timber slash piles in Oregon. ATMOSPHERIC ENVIRONMENT. Elsevier Science Ltd, New York, NY, 150:395-406, (2017).


The purpose of this joint EPA/Oregon effort was to discern whether the practice of using polyethylene sheets to cover biomass slash piles prior to burning caused perceptible increases in air pollutants of concern. The results suggest that use of polyethylene film actually decreases overall pollutant levels by keeping the biomass fuels dry promoting more effective combustion. This study may influence decisions by industry and government agencies relating to the use of polyethylene covers on biomass slash during prescribed fires.


Emissions from burning piles of post-harvest timber slash (Douglas fir) in Grande Ronde, Oregon were sampled using an instrument platform lofted into the plume using a tether-controlled aerostat or balloon. Emissions of carbon monoxide, carbon dioxide, methane, particulate matter (PM2.5), black carbon, ultraviolet absorbing PM, elemental/organic carbon, filter-based metals, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated dibenzodioxins/dibenzofurans (PCDD/PCDF), and volatile organic compounds (VOCs) were sampled for determination of emission factors, the amount of pollutant formed per amount of biomass burned. The effect on emissions from covering the piles with polyethylene (PE) sheets to prevent fuel wetting versus uncovered piles was determined. Results showed that the uncovered (“wet”) piles burned with lower combustion efficiency and higher emission factors for VOCs, PM2.5, PCDD/PCDF, and PAHs. Removal of the PE prior to ignition, variation of PE size, and changing PE thickness resulted in no statistical distinction between emissions. Results suggest that dry piles, whether covered with PE or not, exhibited significantly lower emissions than wet piles due to better combustion efficiency.

Record Details:

Product Published Date: 02/15/2017
Record Last Revised: 06/02/2020
OMB Category: Other
Record ID: 337587