Best Available Retrofit Technology (In "prevention of significant deterioration" (PSD) areas: an exception to requirements for Best Available Control Technology (BACT) in the case of visibility-impairing pollutants. A "retrofit" is an adaptation made to an existing facility. Must consider factors such as compliance costs, existing control technologyies, and energy and environmental impacts.)
Best Available Retrofit Technology. Under NAAQS, EPA requires states to make a BART analysis to predict the effect of forcing all plants to install scrubbers. States must then either carry out the forced scrubbing program, or create a state cap and trade system.
Best Available Retrofit Technology Source: US EPA