Proceedings - Teaching and Learning Centre - Simon Fraser ...

Fraser River Action Plan 3rd Research Workshop
Deposition Methodology
Wet Deposition
1) Collect rainfall
2) Measure content for PAHs or Metals (different samplers)
3) Calculate deposition rate from concentration and surface area of sampler:
• Depos’n Rate = Conc/day /Area
(mg/m 2 /day) = (mg/L/day) / (m 2 )
Dry Deposition
1) Collect particulate on filter media in separated size fractions
2) Calculate volume of air sampled
3) Calculate deposition rate from relationship with particle size (diameter)
• (too complicated to show here)
Calculate Average Atmospheric Contribution to
Land and Water Areas
1) Calculate yearly dry deposition contribution
• Yearly Dry depos’n = [Dry dep rate * #Dry Days/year]
2) Calculate yearly wet deposition contribution
• Yearly Wet depos’n = [Wet dep rate * #Wet Days/year]
3) Determine yearly airborne input of PAHs/Metals to the Still Creek —
Burnaby Lake — Brunette River watershed
• Yearly Total depos’n = [Yearly Wet dep + Yearly Dry dep]
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