Introduction

Gasoline vapors (VOC's) are emitted during the storage and distribution of gasoline fuels. Sources of emissions include gasoline stations, bulk gasoline terminals and gasoline transport tanks. Once released these hydrocarbon vapors act as ozone precursors contributing to the formation of lower atmospheric ozone (smog). Gasoline vapors also contain toxic compounds, such as, benzene, toluene and xylene.

Control of gasoline vapors from refueling and bulk distribution is done using Stage I (vapor balancing during bulk loading) and Stage II (special vapor recovery refueling nozzles) controls. The Northwest Clean Air Agency (NWCAA) inspects over 200 facilities a year for compliance with applicable vapor control regulations and runs an annual registration program for stations operating with sales over 200,000 gallons a year.