Section 580 - VOLATILE ORGANIC COMPOUND CONTROL580.1 The Board of Directors has noted the measurement of ozone concentrations (one hour ave.) nearing the Federal ambient standard at the northern and southern boundaries of the NWCAA jurisdiction. The expanding population and the presence of four large refineries contribute volatile organic compound (VOC) emissions to the atmosphere. Photochemically reactive VOC's are precursors to ozone formation. In order to maintain the current attainment status for ozone, the Board has adopted specific measures to control VOC emissions. Reasonable Available Control Technology (RACT) is required for existing refinery operations, gasoline marketing, and in the use of cutback asphalt. RACT is defined as the lowest emission limit that a particular source is capable of meeting by the application of control that is reasonably available considering technological and economic feasibility. Wash. Admin. Code Northwest Clean Air Agency, 500, 580