Two years ago, the Torrance oil refinery was the scene of a massive explosion that left four workers injured. Without warning, that incident literally rocked the greater community, discharging plumes and debris into the air, rattling windows and roof shingles of nearby homes, and blanketing houses and other buildings with ash. While no toxic chemicals were released into the neighboring community during that explosion, several scientists and residents in the city say they fear another explosion could be  deadly. As Eytan Wallace reports, residents are nervous because the refinery uses hydrofluoric acid – a chemical that could harm or potentially kill humans upon contact. Refinery officials, however, maintain the refinery is safe.