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EXHIBIT 21
SUBSIDIARIES OF TETRA TECH, INC.
| NAME | JURISDICTION OF FORMATION | |
|---|---|---|
| Advanced Management Technology, Inc. | VIRGINIA | |
| Ardaman & Associates, Inc. | FLORIDA | |
| Chen-Northern, Inc. | COLORADO | |
| Cosentini Associates, Inc. | NEW YORK | |
| Engineering Management Concepts, Inc. | CALIFORNIA | |
| Evergreen Utility Contractors, Inc. | WASHINGTON | |
| eXpert Wireless Solutions, Inc. | DELAWARE | |
| FHC, Inc. | OKLAHOMA | |
| GeoTrans, Inc. | VIRGINIA | |
| Hartman & Associates, Inc. | FLORIDA | |
| Kansas City Testing Laboratory, Inc. | MISSOURI | |
| KCM International, Inc. | WASHINGTON | |
| KCM, Inc. | WASHINGTON | |
| LAL Corporation | DELAWARE | |
| MFG, INC. | DELAWARE | |
| Nebraska Testing Corporation | NEBRASKA | |
| Rizzo Associates, Inc. | MASSACHUSETTS | |
| Sciences International, Inc. | DELAWARE | |
| SCM Consultants, Inc. | WASHINGTON | |
| SCM Staff Placement Specialist, Inc. | WASHINGTON | |
| SCM Architecture and Planning, PC | OREGON | |
| Tetra Tech Canada Ltd. | ONTARIO, CANADA | |
| Tetra Tech Caribe, Inc. | PUERTO RICO | |
| Tetra Tech Construction Services, Inc. | COLORADO | |
| Tetra Tech Consulting & Remediation, Inc. | DELAWARE | |
| Tetra Tech EM Inc. | DELAWARE | |
| Tetra Tech Executive Services, Inc. | CALIFORNIA | |
| Tetra Tech FW, Inc. | DELAWARE | |
| Foster Wheeler Environmental Corporation (Mass.) | MASSACHUSETTS | |
| Foster Wheeler Environmental Corporation (Ohio) | DELAWARE | |
| River Corridor Closure, LLC | DELAWARE | |
| Tetra Tech International (BVI) Ltd. | BRITISH V. I. | |
| Tetra Tech Leasing, LLC | DELAWARE | |
| Tetra Tech NUS, Inc. | DELAWARE | |
| Tetra Tech RMC, Inc. | DELAWARE | |
| Tetra Tech Technical Services, Inc. | DELAWARE | |
| Tetra Tech Wired Communications of California, Inc. | CALIFORNIA | |
| The Thomas Group of Companies, Inc. | DELAWARE | |
| Thomas Management Services, LLC | NEW YORK | |
| Thomas Communications & Technologies, LLC | NEW YORK | |
| Thomas Environmental Services, LLC | NEW YORK | |
| America's Schoolhouse Council, LLC | NEW YORK | |
| America's Schoolhouse Consulting Services, Inc. | NEW YORK | |
| Vertex Engineering Services, Inc. | MASSACHUSETTS | |
| Western Utility Cable, Inc. | ILLINOIS | |
| Western Utility Contractors, Inc. | ILLINOIS | |
| Whalen & Company, Inc. | DELAWARE | |
| Whalen do Brasil, Ltda. | BRAZIL | |
| Whalen Service Corps Inc. | DELAWARE | |
| Whalen/Sentrex LLC | CALIFORNIA |
All subsidiaries, other than Tetra Tech Canada Ltd., are wholly-owned, directly or indirectly, by Tetra Tech, Inc.
SUBSIDIARIES OF TETRA TECH, INC.