Alyeska Pipeline Services Co
Agrium KPO
Air Products & Chemicals
Akzo Nobel Chemicals Inc
Amoco Petroleum Co
Anadarko Petroleum Corporation
Ashland Petroleum Co
BDM Petroleum Technologies
BP America Production
BP Amoco
British Petroleum Corp
Burlington Resources Oil & Gas
Chesapeake Energy
Chevron Chemical Co
Chevron ETC
Chevron Phillips Chemical Co
Chevron Products Company
Chevron Research & Technology Co
Citgo Petroleum Co
Clark Refining Co
Coastal Petroleum Co
Coffeeville Resources Refining & Marketing Co
Continental Resources Inc.
Cumberland Farms Inc
Conoco Phillips
D & H Petroleum & Environmental
Dow Chemical Co
DuPont Chemical Co
El Paso Energy Co
Elf Atochem
Enbridge
Encana Oil & Gas LLC (USA)
Equilon Enterprises LLC
Exxon Company USA
ExxonMobil Corp
ExxonMobil de Colombia SA

Flint Hills Resources Alaska
H & N Chemical
Houston Pipeline Co
Hovensa LLC (Virgin Islands)
IE DuPont de Nemours & Co
Imperial Oil Ltd (Canada)
Imperial Oil Resources
Kerr-McGee Chemcial Co
Kinder Morgan
Marathon Ashland Pipeline Co
Mobil Oil Co
Natural Gas Pipeline Co
Nexen Inc (Canada)
Olin Corp
Oxford Farms
Peoples Gas System Inc
Petro Chem Environmental Systems
Phillips 66
Phillips Petroleum Co
Plantation Pipeline Co
Red Willow Production Company
Rice Operating Co
Shell Development Co
Shell Global Solutions
Shell Martinez Refining Co
Shell Oil Products Co
Southern Petroleum Labs
Sunoco
Taminco
Tesoro Hawaii Corp
Texaco
Ultramar Diamond Shamrock Corp
Union Carbide
Valero Energy Corp
Williams Gas Pipelines - Transco
XTO Energy