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IDEM > Forms > AES-03: Stack Parameters AES-03: Stack Parameters

AES-03: Stack Parameters

Stacks can be either physical or logical stacks. Physical stacks are just that, a structure that vents emissions to the atmosphere. These are the most familiar stacks to people. Logical stacks are a little more difficult an idea. These can be best described as emissions escape points like doors, windows or building vents.

Section 6: Stack Information

  1. Stack ID - This is a numeric field used by OAQ to associate a specific stack with the process it vents. This must be a number and should be in sequential order.
  2. Description - Include a short description of the stack that will be meaningful to you.
  3. Height - The stack height must be given in feet. Enter the vertical distance between the point of discharge and the ground, when it can be identified. If no definable stack height exists supply a value for a vent height. For processing that takes place within a building, but is not attached to a stack, the building itself would be considered the "stack" and any window, roof, vent, door, etc. would be considered the exit point.
  4. Diameter - Enter the inside diameter of a round gas exit point of emission, measured in feet. If the exit is not round, calculate D = 1.128 square root of A; where A = cross-sectional area in square feet and D = equivalent diameter.
  5. Flow - Enter the exhaust gas flow rate for the stack in actual cubic feet per minute (acfm). If an actual measurement is not available, use the design or maximum value.
  6. Temp - The temperature of the gas exiting the stack or vent in degrees Fahrenheit. If the exit gas is at ambient temperature use 70°F.
  7. Latitude - Enter the latitude or UTM Vertical (Northing) coordinate used to define the location of the point of discharge. You need to indicate the coordinate used by circling the method at the top of the column. Latitude must be in degrees, minutes, seconds. UTMs must be in kilometers.
    • Tip: If you do not know the specific coordinates of the stack you may use the4 facility coordinates.
  8. Longitude - Enter the longitude or UTM Horizontal (Easting) coordinate used to define the location of the point of discharge. You need to indicate the coordinate used by circling the method at the top of the column. Latitude must be in degrees, minutes, seconds. UTMs must be in kilometers.