| Irving Forest Services Limited |
| J.D. Harvester Works |
| Jamestown Board of Public Utilities |
| Kansas Power & Light |
| Kennecott Utah Copper Corp. |
| Kentucky Power Company |
| Kentucky Utilities Company |
| Kimberly Clark Forest Products |
| Kincaid Generation, LLC |
| Lafarge Corporation |
| Langeloth Metallurgical Co. |
| Lansing Board of Water & Light |
| Lecorp |
| Lehigh Portland Cement |
| Lincoln Pulp and Paper |
| Longview Fibre Company |
| Louisiana-Pacific Corporation |
| Louisville Gas & Electric |
| LTV Steel Company |
| Lyonsdale Power Co., LLC |
| Martin Marietta Magnesia Specialties |
| Mead Paper Co. |
| Medical College of Toledo, Ohio |
| Medusa Cement Co. |
| MidAmerican Energy Co. |
| Midwest Generation EME, LLC |
| Mineraux Noranda |
| Minnkota Power Cooperative |
| Mirant Mid-Atlantic, LLC |
| Mississippi Power Co. |
| Mobil Oil Company |
| Monongahela Power Company |
| Montana-Dakota Utilities Co. |
| Municipal Power & Light, Henderson, Kentucky |
| Murphy Oil Co. |
| National Cement Co. |
| National Steel Corporation |
| Nebraska Public Power |
| Nevada Power Company |
| New Brunswick Power Corp. |
| Norske Skog Canada Limited |
| North Texas Cement |
| Northeast Utilities |
| Northern Indiana Public Service |
| Northshore Mining Company |
| Norwalk Power, LLC |
| Nova Scotia Power, Inc. |
| NRG Energy, Inc. |
| Ogden Martin Energy Group, Inc. |
| Ohio Power Company |
| Ohio Valley Electric Corp. |
| Olmsted Waste-To-Energy |
| Ontario Power Generation, Inc. |
| Orion Power |
| Ottertail Power |
| PacifiCorp |
| Packaging Corp. of America |
| Para-Ag |
| Pope & Talbot Limited |
| Potash Corporation of Saskatchewan, Inc. |
| Potlatch Corp. |
| Potomac Edison Company |
| Power Process Engineering |
| PPG Industries, Inc. |
| PSI Energy Public Service Co. of New Hampshire |
| Public Service of Colorado |
| Public Service of New Hampshire, Newington Station |
| Quantum Chemical Company |
| Regional Waste Systems, Inc. |
| Rhone-Poulenc Ag Company |
| Richmond Power & Light |
| RMC Lonestar |
| Rochester Public Utilities |
| Rock-Tenn Company |
| Rocky Mountain Steel Mills |
| Rouge Steel Company |
| Royal Ordinance of N. America |
| Southern Mississippi Electric Power |
| S.D. Warren |
| Salt River Project |
| San Miguel Electric Coop, Inc. |
| Santee Cooper |
| Sappi Fine Paper of North America |
| Saskpower |
| Shell Oil Company |
| Sikeston Board of Municipal Utilities |
| Simpson Pasadena Paper Co. |
| Sithe Mystic LLC |
| Smurfit-Stone Container Corp. |
| Southern Illinois Power Coop. |
| Solutia, Inc. |
| Southern Indiana Gas & Electric |
| Southwestern Electric Power Co. |
| St. Anne Nackawic Pulp Co. |
| St. Lawrence Cement |
| State Line Energy, LLC |
| Stelco Limited |
| Stone Consolidated Corporation |
| Sunbury Generation, LLC |
| Suncor Inc. Oil Sands Group |
| Svedala Limited |
| Syncrude Research |
| Tennessee Valley Authority |
| Thompson Creek Mining Limited |
| Transalta Utilities Corp. |
| Tri-State Generation Transmission |
| Trigen-Cinergy Solutions, LLC |
| TXU Electric Co. |
| United States Enrichment Corp. |
| Upm-Kymmene Miramichi, Inc. |
| Upper Peninsula Power Company |
| Vanderbilt Chemical |
| Viking Energy |
| Virginia Electric & Power Co. |
| West Penn Power Company |
| Westchester Resco Co., L.P. |
| Western Kentucky Energy |
| Westinghouse |
| Westvaco Corporate Center |
| Weyerhaeuser Company Limited |
| Wheelabrator Environmental Systems |
| Willamette Industries, Inc. |
| Wisvest Connecticut, LLC |
| Xcel Energy Services, Inc. |
| Zinc Corporation of America |