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10-K - FORM 10-K - TETRA TECH INCa2195448z10-k.htm
EX-23 - EXHIBIT 23 - TETRA TECH INCa2195448zex-23.htm
EX-32.1 - EXHIBIT 32.1 - TETRA TECH INCa2195448zex-32_1.htm
EX-31.2 - EXHIBIT 31.2 - TETRA TECH INCa2195448zex-31_2.htm
EX-32.2 - EXHIBIT 32.2 - TETRA TECH INCa2195448zex-32_2.htm
EX-31.1 - EXHIBIT 31.1. - TETRA TECH INCa2195448zex-31_1.htm
EX-10.18 - EXHIBIT 10.18 - TETRA TECH INCa2195448zex-10_18.htm

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Exhibit 21

Subsidiaries of Tetra Tech, Inc.

NAME
  JURISDICTION OF
FORMATION

Advanced Management Technology, Inc. 

  VIRGINIA

America's Schoolhouse Consulting Services, Inc. 

  NEW YORK

America's Schoolhouse Council, LLC

  NEW YORK

ARD, Inc. 

  VERMONT

Ardaman & Associates, Inc. 

  FLORIDA

BAS Construction Co. 

  CALIFORNIA

BAS Landfill Gas Limited Partnership

  ARIZONA

BAS Construction, L.P. 

  CALIFORNIA

Bryan A. Stirrat & Associates

  CALIFORNIA

Cosentini Associates, Inc. 

  NEW YORK

Delaney Crushed Stone Products, Inc. 

  NEW YORK

Engineering Management Concepts, Inc. 

  CALIFORNIA

GeoTrans, Inc. 

  VIRGINIA

Hartman & Associates, Inc. 

  FLORIDA

Haselwood Enterprises, Inc. 

  TENNESSEE

INCA Engineers, Inc. 

  WASHINGTON

IP3 Afrique, LLC

  SENEGAL

IP3 Mena, LLC

  EGYPT

Kansas City Testing Laboratory, Inc. 

  MISSOURI

KFM Engineering, Inc. 

  CALIFORNIA

Maxim International S.R.L. 

  PERU

Millennium—IP3 Partners, LLC

  DELAWARE

Segura/IP3 Partners, LLC

  DELAWARE

Tetra Tech Alaska, L.L.C. 

  ALASKA

Tetra Tech Argentina S. A. 

  ARGENTINA

Tetra Tech Australia Pty. Ltd. 

  AUSTRALIA

Tetra Tech Bioenergy, LLC

  DELAWARE

Tetra Tech Cape Canaveral, LLC

  FLORIDA

Tetra Tech Caribe, Inc. 

  PUERTO RICO

Tetra Tech Construction Services, Inc. 

  COLORADO

Tetra Tech Consulting & Remediation, Inc. 

  DELAWARE

Tetra Tech EC (Mass.) Corporation

  MASSACHUSETTS

Tetra Tech EC (Ohio) Corporation

  DELAWARE

Tetra Tech EC, Inc. 

  DELAWARE

Tetra Tech Electric, Inc. 

  NEW JERSEY

Tetra Tech EM Inc. 

  DELAWARE

Tetra Tech Executive Services, Inc. 

  CALIFORNIA

Tetra Tech Facilities Construction, LLC

  NEW JERSEY

Tetra Tech IC, Inc. 

  CANADA

Tetra Tech India Limited

  INDIA

Tetra Tech International (BVI) Ltd. 

  BRITISH V. I.

Tetra Tech International, Inc. 

  DELAWARE

Tetra Tech NUS, Inc. 

  DELAWARE

Tetra Tech RAC Craft, LLC

  DELAWARE

Tetra Tech Technical Services, Inc. 

  DELAWARE

Tetra Tech Tesoro, Inc. 

  VIRGINIA

Tetra Tech Wired Communications of California, Inc. 

  CALIFORNIA

The Delaney Group, Inc. 

  NEW YORK

NAME
  JURISDICTION OF
FORMATION

The Institute for Public-Private Partnerships, Inc. 

  DELAWARE

Thomas Communications & Technologies, LLC

  NEW YORK

Thomas Environmental Services, LLC

  NEW YORK

Wardrop Engineering Inc. 

  CANADA

Wardrop (Ghana) Ltd. 

  GHANA

Western Utility Cable, Inc. 

  ILLINOIS

Western Utility Contractors, Inc. 

  ILLINOIS

Western Utility Electric, Inc. 

  ILLINOIS

Whalen & Company, Inc. 

  DELAWARE

Whalen Management Services, Co. 

  CANADA

Whalen Service Corps Inc. 

  DELAWARE



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