The Integrated Atmospheric Deposition Network (IADN)
Hazardous Air Pollutants (HAPs)
Air Emissions in the Great Lakes
The Integrated Atmospheric Deposition Network (IADN) has been in operation since 1990 under the guidance of an implementation plan signed in that year. The first implementation plan committed the United States and Canada to work cooperatively towards the initiation of the IADN. It also guided the five original, cooperating IADN agencies in meeting their joint obligation. Since 1999 the program is comprised of the following three agencies:
- The U.S. Environmental Protection Agency (U.S. EPA)
-
Environment Canada's (EC) Meteorological Service of
Canada
-
EC's Ecosystem Health Division of Ontario Region (EHD)
In 1997, the IADN Steering Committee reviewed the progress of the IADN program in a technical summary. The Second Implementation Plan for IADN (IP2), signed in 1998, outlines goals and plans for IADN for the period 1998-2004.
IADN is specifically called for, by name, in Annex 15
of the Great Lakes Water Quality Agreement (GLWQA). In
Canada, these activities are delivered federally through
the Great Lakes program, and activities delivered at the
provincial level are described in the Canada-Ontario
Agreement (COA). The mandate for IADN also resides in
Section 112(m) of the U.S. Clean Air Act Amendments of
1990 (CAA). The U.S./Canada Binational Great Lakes
Toxics Strategy (BGLTS), signed in 1997, calls for
monitoring of the atmospheric deposition of
toxic chemicals
- Determine, with a specified degree of confidence the atmospheric loadings and trends (both spatial and temporal) of priority toxic chemicals to the Great Lakes and its basin on, at least, a biennial basis;
- Acquire quality-assured air and precipitation concentration measurements, with attention to continuity and consistency of those measurements, so that trend data are not biased by changes in network operations or personnel; and
- Help determine the sources of the continuing input of those chemicals.
Station Placement and Number
IADN has been designed with one
Master Station
The Network is "a leading international effort in the assessment of the role of the atmospheric impacts of persistent, toxic substances on aquatic systems" (Peer Review, 1997). The second phase of IADN is scheduled to run until 2004. No major changes to the Network are anticipated, although potential modifications will be discussed and plans implemented.