Atmospheric Deposition: Air Toxics At Lake Superior

EPA Grant Number: R827649C003
Subproject: this is subproject number 003 , established and managed by the Center Director under grant R827649
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: Center for Air Toxic Metals® (CATM®)
Center Director: Groenewold, Gerald
Title: Atmospheric Deposition: Air Toxics At Lake Superior
Investigators: Laudal, Dennis L. , Folkedahl, Bruce C. , Pavlish, John H. , Erickson, Thomas
Institution: University of North Dakota
EPA Project Officer: Chung, Serena
Project Period: October 15, 1999 through October 14, 2002
Project Amount: Refer to main center abstract for funding details.
RFA: Center for Air Toxic Metals (CATM) (1998) RFA Text |  Recipients Lists
Research Category: Targeted Research


The EPA in conjunction with the states of Wisconsin, Minnesota, and Michigan has been conducting studies to determine the deposition of mercury into Lake Superior. It is expected that a comprehensive test program will be funded in 1998 which is designed to determine the fate of anthropogenic mercury in the Lake Superior region and then determine the effect of mercury emissions on aquatic systems. It is expected that the data and predictive modeling based on the data will help determine the effect these emissions have in the whole Lake Superior region. CATM will help to coordinate the activities, work with personnel from the University of Michigan, Academy of Natural Science, and TetraTech to determine the state of the art of receptor methodology for trace elements and atmospheric modeling, share and discuss past research results and appropriate measurement methods with the team, and integrate EERC's emission models with available atmospheric models. The project has three primary tasks. Task 1 is to review the current state of knowledge of atmospheric sampling and atmospheric deposition models. Task 2 is to coordinate the efforts of the CATM project with the Lake Superior studies. The final task will be to link the EERC emission models with the deposition models that will be developed from the Lake Superior project.

The goal of the project is to determine the current state of knowledge for atmospheric sampling and receptors, interactions, reactions of emissions, deposition mechanisms, and atmospheric deposition models and to apply this knowledge to studies that are expected to be conducted at Lake Superior. The main objectives are as follows:

  • Perform literature searches on the above listed issues
  • Interact with the research team for the Lake Superior study and supply them with the results of the literature searches
  • Interact with the EPA and others on potential enhancement of mercury modeling
  • Demonstrate the EERC point-source emission model in conjunction with an atmospheric deposition model


The project is divided into three tasks: review of the current state of knowledge, coordination with Lake Superior studies, and demonstration of models. Although the CATM project is linked with the proposed project "Fate of Mercury in the Lake Superior Region," all but Task 2 can continue even if the Lake Superior project is not funded. Each task is described below.

Task 1 - Review of Current State of Knowledge

This task is to determine the current state of knowledge for atmospheric sampling and receptors, interactions/reactions of emissions, deposition mechanisms, and atmospheric deposition models. These reviews are being conducted through literature searches and communication with academia, government, and industrial groups.

Task 2 - Coordination with Lake Superior Studies

This task is to ensure that the insight gained from Task 1 is used to aid the studies at Lake Superior. As part of this task, CATM is contributing to all planning and management decisions for the proposed Lake Superior studies, and once the project is funded, CATM will continue to be very active in all planning decisions. This task will also track all results from the work conducted, and the data will be included within the CATM database.

Task 3 - Demonstration of Models

Currently, several models are used by EPA and other organizations to predict the resultant deposition pattern of emissions from an industrial process. The Lake Superior project will provide data that will enhance the accuracy and usability of these models to predict the deposition of mercury. CATM will work very closely with the University of Michigan's Air Quality Laboratory and the EPA to link the TraceTran point source model (used by CATM) to the deposition models.


Most of the work to date has been in Tasks 1 and 2. The literature review is an ongoing activity. A research plan for the project entitled "The Fate of Mercury in the Lake Superior Region" is currently being reviewed by several agencies, including EPA, DOE, EnviroCanada, and EPRI.

Regular discussions are conducted between CATM personnel and Dr. Gerald Keeler from the University of Michigan's Air Quality Laboratory. Dr. Keeler will be the person primarily responsible for conducting modeling activities in the Lake Superior region. CATM has helped Dr. Keeler develop a geographical understanding of the region surrounding the Clay Boswell Power Plant. The Clay Boswell plant will be one of the power plants that will be sampled. Using this information, Dr. Keeler has developed preliminary locations for deposition sampling. In addition, literature reviews and discussions are ongoing to provide information on tracers which will provide a link between the deposition samples and emissions from the power plant. Although no decisions have been made as to what tracers would work best, several rare-earth compounds are being discussed as possibilities.


This project in conjunction with the Fate of Mercury in the Lake Superior Region is designed to address the needs, as stated by the Science Advisory Committee, in the area of anthropogenic sources of mercury and its deposition both locally and regionally. The overall goal of the Lake Superior project is to provide data and modeling information that will help answer the question, How does a change in mercury emissions from a source change the concentration of mercury in fish in a given area? To answer that question, the concentration, species, deposition, and transport of mercury and cycling within lakes must be either measured or accurately modeled. The CATM portion of this project will begin to relate modeling of point-source mercury emissions with the atmospheric mercury models that will be enhanced as part of the overall project. In addition, the point-source models should help in determining the speciation of mercury at the stack. Good mercury speciation data are very important for modeling local, regional, and global deposition of mercury.

Supplemental Keywords:

Scientific Discipline, Toxics, Air, Geographic Area, Water, Chemical Engineering, air toxics, Environmental Chemistry, HAPS, State, Atmospheric Sciences, Chemistry and Materials Science, 33/50, Engineering, Chemistry, & Physics, Great Lakes, Mercury, ambient air quality, atmospheric, monitoring, Minnesota, mercury , air pollutants, air sampling, anthropogenic mercury, Lake Superior, mercury & mercury compounds, Mercury Compounds, Wisconsin (WI), atmospheric deposition, heavy metals

Progress and Final Reports:

  • 2000
  • 2001
  • Final

  • Main Center Abstract and Reports:

    R827649    Center for Air Toxic Metals® (CATM®)

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R827649C001 Development And Demonstration Of Trace Metals Database
    R827649C002 Nickel Speciation Of Residual Oil Ash
    R827649C003 Atmospheric Deposition: Air Toxics At Lake Superior
    R827649C004 Novel Approaches For Prevention And Control For Trace Metals
    R827649C005 Wet Scrubber System
    R827649C006 Technology Commercialization And Education
    R827649C007 Development Of Speciation And Sampling Tools For Mercury In Flue Gas
    R827649C008 Process Impacts On Trace Element Speciation
    R827649C009 Mercury Transformations in Coal Combustion Flue Gas
    R827649C010 Nickel, Chromium, and Arsenic Speciation of Ambient Particulate Matter in the Vicinity of an Oil-Fired Utility Boiler
    R827649C011 Transition Metal Speciation of Fossil Fuel Combustion Flue Gases
    R827649C012 Fundamental Study of the Impact of SCR on Mercury Speciation
    R827649C013 Development of Mercury Sampling and Analytical Techniques
    R827649C014 Longer-Term Testing of Continuous Mercury Monitors
    R827649C015 Long-Term Mercury Monitoring at North Dakota Power Plants
    R827649C016 Development of a Laser Absorption Continuous Mercury Monitor
    R827649C017 Development of Mercury Control Technologies
    R827649C018 Developing SCR Technology Options for Mercury Oxidation in Western Fuels
    R827649C019 Modeling Mercury Speciation in Coal Combustion Systems
    R827649C020 Stability of Mercury in Coal Combustion By-Products and Sorbents
    R827649C021 Mercury in Alternative Fuels
    R827649C022 Studies of Mercury Metabolism and Selenium Physiology