AES Deepwater

Amerada-Hess

Amoco

ARCO Petrochemical

Aristech, Inc.

BP Oil (Alaska)

Chevron Oil

Conoco Inc.

Contrina (Venezuela)

Denbury Management

Dow Chemical

Dupont, Corp.

Enichem Elastomers Americas

Enterprise Products

EVALCA, Inc.

EXXON Pipeline

Fina Chemical Corp.

Fina Petroleum, Inc.

First Chemical, Corp.

Geon Corporation

Gulf Chemicals

Halterman Chemical, Inc.

ICI America

Interox Inc.

Lyondell-Citgo Petrochemical

Marathon Petroleum

Merichem Industries

Mobil Oil

Noltex LLP

Occidental Chemical Corp.

Ocensa, Corp.

OXY Cities Services

Petrolite, Corp

Petrozuata/(Venezuela)

Phillips Petroleum

Quantum Chemical

Rhone-Poulenc

Shell Western E & P

Solvay Polymers

Star Enterprises

Sterling Chemical

TEPPCO

Texaco Industries

TRANSCO

Warren Petroleum