Citgo Refinery in Corpus Christi has reported a butane release to the atmosphere that caught fire. Processing vessels and piping at one of the Alkyline Units are involved in the fire at the facility. Citgo also reports that a “very small amount of Hydrogen Fluoride” has the potential for release. PDO Webster has coordinated with the Texas Commission of Environmental Quality (TCEQ). TCEQ personnel on-site has conducted air monitoring and water sampling. As of 1300 hrs on 20 July 2009 TCEQ reports that there have been no off site impacts.