Yesterday, the D.C. Circuit Court of Appeals remanded EPA’s MACT standards for PCBs, polycyclic organic matter, and hexachlorobenzene 
to EPA. Rather than setting specific MACT standards for these compounds, EPA regulated them through “surrogates,” commonly particulate matter. The Sierra Club and others argued that EPA did not adequately justify the use of surrogates.
The three-part test for the adequacy of a surrogate is clear and worth repeating:
(1) the relevant hazardous air pollutant is invariably present in the proposed surrogate;… More