Dispersion technique means any technique which attempts to affect the concentration of a pollutant in the ambient air by:
(i) Using that portion of a stack which exceeds good engineering practice stack height:
(ii) Varying the rate of emission of a pollutant according to atmospheric conditions or ambient concentrations of that pollutant; or
(iii) Increasing final exhaust gas plume rise by manipulating source process parameters, exhaust gas parameters, stack parameters, or combining exhaust gases from several existing stacks into one stack; or other selective handling of exhaust gas streams so as to increase the exhaust gas plume rise.
40 CFR § 51.100
As used in this part, all terms not defined herein will have the meaning given them in the Act: