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Project Title: Evaluation of the Extent and Transport Capabilities of PAHs within the Lake Erie Watershed

Project Summary: Download (200 KB PDF)

Synopsis: There are 42 Areas of Concern (AOCs) throughout the Great Lakes basin, 30 of which are wholly or partly within the U.S. borders. Each of these AOCs have been gradually moving toward restoration and recovery of their beneficial uses through broad-based Remedial Action Plans, which prescribe a wide range of actions, ranging from remedial dredging and clean-up to natural attenuation, depending on site-specific factors. Presque Isle Bay, in Erie, Pennsylvania, has been re-designated as an Area of Recovery and is progressing toward a recovery under a program of natural attenuation. Accurate determination of continuing contamination levels, including from atmospheric inputs, are essential in determining the recovery timeline for the bay and what additional measures, if any, are needed to speed and ensure its recovery. This project's goal was to determine the input of polycyclic aromatic hydrocarbons (PAHs), the primary contaminants of concern in the bay, to Presque Isle Bay from the atmosphere and statistically apportion these contaminants to various likely sources.

Chemicals Studied: This project monitored eighteen PAHs: pyrene; benz(a)anthracene; chrysene; benzo(a)pyrene; benzo(b)fluoranthene; benzo(k)fluoranthene; benzo(g,h,i)perylene; dibenz(a,h)anthracene; anthracene; phenanthrene; acenaphthene; acenaphthylene; benzo(e)pyrene; fluoranthene; fluorene; ideno(1,2,3-cd)pyrene;; perylene; and coronene.

Geographic Areas: The project included three monitoring sites around Presque Isle Bay, near the shore of Lake Erie in Northwest Pennsylvania. Although the project covers only a small region, the methods and results will have very important implications to the numerous other AOCs around the region.

Project Duration: Monitoring occurred over a 12-month period, from February 2005 through January 2006. Following this, the data was be analyzed to determine loading and source contributions.

Methods Used: Gaseous and particulate air samples and wet deposition samples were taken at three sites: one in the city of Erie; one upwind of Presque Isle Bay; and one downwind of the bay. Air samples were collected by high volume samplers with quartz fiber filters and XAD-2 resin. Wet deposition samples were collected with event-based precipitation collectors. These samples were analyzed for the PAH compounds being studied. In addition to calculating total deposition to the bay, the data was analyzed with the Chemical Mass Balance model to apportion the contributions of several likely sources

Potential Results and Implications: The study has numerous important implications, including: evaluating the concentration of PAHs in particulate and gaseous form in ambient air in the Erie area; estimating the PAH fluxes into Presque Isle Bay by considering dry particle deposition, wet deposition via precipitation and gaseous air-water exchange; characterizing the potential sources of PAHs within air and precipitation samples based on the relative proportions of various species; estimating whether the potential sources of atmospheric PAHs are predominately from local or regional sources; and characterizing the transport of PAHs within the local area by comparing data between sites upwind, downwind and within the city of Erie. In addition to providing highly valuable information to the local Remedial Action Plan committees, the study is a valuable demonstration to the other Great Lakes AOCs.

Project Contact:
Michelle Homan, Ph.D.
Department of Environmental Science & Engineering
Gannon University, Box 3663
Erie, PA 16541
Phone: (814)871-5691
Email: homan@gannon.edu

Documents: Final Report (0.8 MB PDF)