United States

Alaska Gold Company
Alta Gold Company
Alternate Energy Resources
Archer Daniels Midland
Bay State Gas Company
Birmingham Steel
Boise Cascade
Bunker Limited Partnership
Bunker Hill and Sullivan Mining
CenterPoint Energy
Central Hudson Gas & Electric
Copper Range Company
Couer d'Alene Mines
Denver Public Schools
Devon Energy Corp.
Fina Oil and Chemical
GATX Corporation
General Mills
GNB Technologies Inc.
Gould Electronics Inc.
Gulf Resources & Chemical
Harsco Corporation
Hecla Mining Company
Helena Chemical Company
Holly Corporation
Hunt Oil Company
ISPAT Inland Inc.
J.R. Simplot Company
Kennecott Corporation
Keystone Industries Incorporated
Kinder Morgan, Inc.
Lamson & Sessions, Co.
LG&E Energy Corp.
Lockheed Martin
Louisiana-Pacific
Mack Trucks, Inc.
MAPCO Inc.
Markovitz Enterprises Inc.
McCarty's Superfund Site PRP Group
McWane, Inc.
Mueller Europe Ltd.
Mueller Europe S.A.
Mueller Industries, Inc.
Newmont Mining
NL Industries, Inc.
Northern Utilities, Inc.
Northwest Pipeline
Pegasus Gold Inc.
The Pillsbury Company
The Pyrites Company, Inc.
Schwartz &. Company, Inc.
The Scotts Company
SESCO Group
Sequa Corporation
South Boulevard Properties, Inc.
Sunshine Mining and Refining
Texas Gas Transmission
Transcontinental Gas Pipe Line
The University of Texas System
U.S. Borax, Inc.
U.S. Department of Energy
U.S.S. Lead
Valley Nitrogen Company
Velsicol Chemical Company
Vulcan Materials Company
Wainoco Oil Corporation
Weyerhaeuser Company
The Williams Companies, Inc

Canada

Canadian Natural Resources Ltd.
Canerector Inc.
Husky Energy Inc.
Inmet Mining Corporation
Nexen Inc.
Tonolli Canada Ltd.

UK/Europe

Lindsey Oil Refinery (U. K.)
Miracle Garden Care (U. K.)
PetroFina S.A, (Belgium)
Raffineria di Roma (Italy)
Sigma Coatings (Netherlands)