Allied Waste Industries, Inc.

Allwaste, Inc.

American Ecology Corporation

Appliance Recycling Centers of America, Inc.

Azcon Corporation

Berliner Stadtreinigungsbetriebe

Brambles Industries Limited

Browning-Ferris Industries, Inc.

Chemical Waste Management, Inc.

Clean Harbors, Inc.

Copart Inc.


Ecology and Environment, Inc.


Industrial Services of America, Inc.

Ionics, Incorporated

Kelda Group plc

MPW Industrial Services Group, Inc.

Newpark Resources, Inc.

Norcal Waste Systems, Inc.

Pennon Group Plc

Philip Environmental Inc.

Philip Services Corp.

Roto-Rooter Corp.

Roto-Rooter, Inc.

Safety-Kleen Systems Inc.

Sevenson Environmental Services, Inc.

Severn Trent PLC

Shanks Group plc

Shred-It Canada Corporation

Stericycle Inc.

TRC Companies, Inc.

Veit Companies

WMX Technologies Inc.

Waste Connections, Inc.

Waste Holdings, Inc.

Wheelabrator Technologies, Inc.

Windswept Environmental Group, Inc.