||1. Calculate the distance away from each turbine (find distance). Calculate the log10, or inverse distance squared etc ... to get the decay. Modify values to get the way you want (* or / by a constant)
2. If the turbines are different sizes. Add a field of magnitude (turbine A is 2, Turbine B is 1 ... A is twice the size of B). Calculate the Analysis-Assign Promity based on the new magnitide field.
3. Mutiple the magnitude grid (2) by decay (1) to get result.
If the turbines are close together, then you will have to do each seperately. Then get the maximum value from each of the resulting grids to get final noise pollution. This result will look better, because the noises will overlap.
For a cool effect final effect (presentation wise), scan in a base map and in 3D analysis display the sound pollution as a 3D object (bubble) above the scan. Set to 50% transparent. Looks impressive that way.
Good luck :D