BASF Corporation
Bayer Corporation
Bethlehem Steel Corporation
Borden Chemicals & Plastics
BP Products North America
BP Chemicals, Inc.

Cavenham Forest Industries
Cecos International
Celanese Ltd.
CenterPoint Energy
Chevron Chemical Company
Citgo Petroleum
Conestoga-Rovers & Assoc.
Conoco Refining Company
Consolidated Aluminum
Criterion Catalyst Company
Crompton, Witco Products     and Services

Department of Energy (SPR)
Department of the Interior     (BOR)
Diamond-Koch
Dolet Hills Mining Venture
Dow Chemical USA
Dyn-McDermott

E. I. DuPont
Energy Resources     Management, LLC
Engelhard Corporation
Enterprise Products
Environmental Disposal     Systems, Inc.
Environmental Protection     Agency
Ethyl Corporation
Exxon Company, USA
Exxon Production Research     Company

Farmland Industries
Ferrell Gas
Filtrol Corporation
Fina Oil & Chemicals
Ford Motor/Rouge Steel
Freeport Chemical

Great Lakes Chemical Corp.

Hampshire Chemicals
Hardage Site Remedy Corp.
Holly Corporation
Huntsman Polymers
Huntsman Petrochemical

IMC Chemicals Group, Inc.
Inland Steel Company
International Minerals and     Chemicals
ISK Magnetics

Kaiser Aluminum & Chemical
Kerr-McGee Chemical, LLC

LA Dept. of Natural Resources
LTV Steel Company
Lubrizol Corporation
Lyondell/Equistar

M-D Building Products, Inc.
Marathon Oil Company
Martin Marietta
Merisol USA LLC
Midwest Steel Division
Millenium Chemicals
Mobil Oil Corporation
Mobil Pipeline Company
Monsanto Company
Morton International
Motiva Enterprises, LLC
Murray Rubber

Navajo Refining Company
New Avoca Gas Storage, LLC
Newpark Environmental Services
Newpark Resources, Inc.
NL Industries

Occidental Chemical Corporation
Onyx Environmental Services, LLC

Parke-Davis
Perma Fix, Inc.
Pfizer, Inc.
Phillips Petroleum Company
Pool Company
PPG Industries, Inc.

Reliant Resources
Reynolds Metals Company
Rohm & Haas

Seadrift Pipeline
Searle Chemicals
Shell Oil Company
Shell Offshore, Inc.
Shell Chemical Company
Solutia Inc.
Southeast Texas Environmental
Southwestern Public Service Co.
Star Enterprises, Inc.
Sterling Chemicals, Inc.
Suburban Propane
Syngenta Crop Protection     (Zeneca)

Tenneco
Tennessee Valley Authority
Texaco, Inc.
Texas Brine
TexTin Corporation
The GNI Group, Inc.
Tomen-Agro, Inc.
Total Petroleum

UOP
Union Carbide Corporation
Union Texas Petroleum
Uniroyal, Inc.
US Steel
USX Corporation

Velsicol Chemical Corporation
Vopak Industrial Services USA,     Inc. (Empak)
Vulcan Materials

Western Resources
Western Gas Resources