A multi-isotope approach for estimating industrial contributions to atmospheric nitrogen deposition in the Athabasca oil sands region in Alberta, Canada

Abstract

Industrial nitrogen (N) emissions in the Athabasca oil sands region (AOSR), Alberta, Canada, affect nitrate (NO3) and ammonium (NH4) deposition rates in close vicinity of industrial emitters. NO3eN and NH4eN open field and throughfall deposition rates were determined at various sites between 3 km and 113 km distance to the main oil sand operations between May 2008 and May 2009. NO3 and NH4 were analyzed for d15NeNO3, d18OeNO3, D17OeNO3 and d15NeNH4. Marked differences in the d18O and D17O values between industrial emissions and background deposition allowed for the estimation of minimum industrial contributions to atmospheric NO3 deposition. d15NeNH4 values also allowed for estimates of industrial contributions to atmospheric NH4 deposition. Results revealed that particularly sites withinw30 km radius from the main oil sands developments are significantly affected by industrial contributions to atmospheric NO3 and NH4 deposition.