|
Ash Grove Cement Company |
Continental Cement Company, LLC |
|
Alumax (Now a part of Alcoa) |
Kleen Industrial Services, Inc. |
| ChemRight Laboratories, Inc. |
Shell Corp. |
|
Holcim Inc. |
|
|
Independent Cement Corporation |
Lafarge Corporation |
|
Lone Star Industries Inc. |
Medusa Cement Company |
|
National Cement Company Inc. |
Portland Cement Association |
|
Redland Aggregates Ltd. |
Rhodia Inc. |
|
Safety-Kleen Corporation |
Southdown Inc. |
|
St. Lawrence Cement Inc. |
Systech Environmental Corporation |
|
Texas Industries Inc. |
Waste Management International |