Document

Exhibit 21.1

Quanta Services, Inc.

Subsidiaries List

The following is a list of the subsidiaries of Quanta Services, Inc. showing the jurisdiction of incorporation or organization and the names under which each subsidiary does business (in italics). The names of certain subsidiaries may be omitted as such subsidiaries, considered as a single subsidiary, would not constitute a significant subsidiary.


Subsidiary and Names Under Which Subsidiary Does Business			Jurisdiction of Incorporation or Organization
1 Diamond, LLC Cutting Technology - 1 Diamond, LLC			Delaware
1Diamond AS			Norway
618232 Alberta Ltd. ValAir			Alberta
8246408 Canada Inc. G-TEK G-Vac Advanced Electric Systems, LLC			Quebec
Advanced Utility Testing & Maintenance, LLC Utility Testing & Maintenance, LLC			Delaware
Alexander Publications, LLC			California
Allteck GP Ltd.			British Columbia
Allteck Limited Partnership			British Columbia
Allteck USA, LLC			Deleware
Apprenticeship Programs, Inc			Idaho
Arnett & Burgess Oil Field Construction Limited			Alberta
Arnett & Burgess Pipeliners (Rockies) LLC			Delaware
Arnett & Burgess Pipeliners Ltd.			Alberta
B&N Clearing and Environmental, LLC			Delaware
Banister Pipelines Constructors GP Ltd.			British Columbia
Banister Pipelines Limited Partnership			British Columbia
Blackbox Technologies International			Texas
Blattner Canada, LLC			Minnesota
Blattner Energy, LLC Blattner Energy, PLLC			Minnesota
Blattner Holding Company, LLC Blattner Company			Minnesota
Blattner Investments, LLC			Minnesota
Brent Woodward, Inc.			Oregon
Brink Constructors, Inc. Brink Constructors, Inc. A Corporation Of South Dakota			South Dakota
Cable Communication Services, LLC			Delaware
Calico Real Properties, LLC			Delaware
CanACRE (U.S.A.) Inc.			Delaware
CanACRE (USA) Brokerage, Inc.			Delaware
CanACRE Ltd.			British Columbia
Canadian Utility Construction GP Ltd.			British Columbia


Canadian Utility Construction Limited Partnership			British Columbia
Carolina Power & Signalization, LLC			Delaware
Catalyst Changers Inc.			Alberta
Catalyst Changers Trinidad, ULC			British Columbia
Cat-Spec, Ltd. Cat Spec Limited, LP Cat Spec, Ltd CAT SPEC, Ltd. Cat Spec, Ltd. L.P. Cat Spec, Ltd., LP Cat Spec., Ltd. LP Cat-Spec Ltd, LP CAT-SPEC, Limited Partnership CAT-SPEC, Limited Partnership (Regd Name) CAT SPEC, Ltd. (Part Name) Cat-Spec, Ltd (A Domestic limited Partnership) Cat-Spec, Ltd. Limited Partnership Cat-Spec, Ltd., L.P. Cat-Spec, Ltd., LP (Used in VA By: Cat-Spec, Ltd.)			Texas
Citadel Industrial Services, Ltd. Citadel Industrial Services, L.P. Citadel Industrial Services, Ltd. Limited Partnership Citadel Industrial Services, Ltd., L.P.			Texas
Coe Drilling Pty Ltd.			Australia
Conam Construction Co. Conam Construction Co., Inc.			Texas
Consolidated Power Projects Australia Pty Ltd Conpower Consolidated Power Industries			Australia
Conti Communications, Inc.			Delaware
Crux Subsurface Canada Ltd.			British Columbia
Crux Subsurface, Inc.			Delaware
D.H. Blattner & Sons, Inc.			Minnesota
D.H. Blattner & Sons, LLC			Minnesota
Dacon Corporation			Delaware
Dashiell Corporation Dashiell (DE) Corporation (Dashiell Corporation) Dashiell Corporation DBA Dashiell (DE) Corporation Dacon Corporation			Delaware
Dashiell MI Corporation			Delaware
Digco Utility Construction, L.P. Digco Utility Construction Limited Partnership			Delaware
DOD Fueling Contractors Pty Ltd.			Australia
Dorado Specialty Services, Ltd. Dorado Specialty Services, L.P. Dorado Specialty Services, Ltd. L.P. Dorado Specialty Services, Ltd. Limited Partnership Dorado Specialty Services. Ltd., L.P.			Texas
EHV Power ULC			British Columbia
Elite Construction of Ocala, LLC			Delaware
Elite Fabrication, Ltd. Elite Fabrication, LP			Texas


Elite Piping & Civil, Ltd. Elite Piping & Civil Limited Partnership Elite Piping & Civil Ltd, L.P. Elite Piping & Civil, Limited Partnership Elite Piping & Civil, Ltd. Limited Partnership Elite Piping & Civil, Ltd., L.P. Elite Piping and Civil, L.P.			Texas
Elite Turnaround Specialists, Ltd. Elite Turnaround Specialists Limited Partnership Elite Turnaround Specialists Limited Lp Elite Turnaround Specialists Limited Partnership Elite Turnaround Specialists Ltd. L.P. Elite Turnaround Specialists, L.p. Elite Turnaround Specialists, Limited Partnership ELITE TURNAROUND SPECIALISTS, LTD Elite Turnaround Specialists, Ltd, Lp Elite Turnaround Specialists, Ltd. Limited Partnership Elite Turnaround Specialists, Ltd., LP			Texas
Energy Consulting Group, LLC			Delaware
Energy Services West, LLC			Delaware
Energy Services, West			Delaware
Enscope Pty Ltd			Australia
FiberTel, LLC Fibertel Communications			Utah
FIC GP, LLC			Delaware
Field Personnel Services, LLC			Delaware
First Infrastructure Capital Advisors, LLC			Delaware
First Infrastructure Capital GP, L.P.			Delaware
Five Points Construction Co.			Texas
Flare Construction, LLC Flare Construction, Inc.			Utah
Fleet Services West, LLC			Delaware
Grid Creative, Inc.			Idaho
Grid Manufacturing Corporation Northwest Lineman College			Idaho
Grid Training Corporation Northwest Lineman Center Northwest Lineman College			Idaho
H.L. Chapman Pipeline Construction, Inc.			Delaware
Haverfield International Incorporated Haverfield Aviation Haverfield Aviation, Inc.			Delaware
HBK Engineering, LLC HBK Engineering, PLLC			Illinois
Helibro, LLC			California
Heritage Midstream, LLC			Delaware
Infraestructura ETP de Mexico, S. de R.L. de C.V			Mexico
InfraSource Construction, LLC Infrasource Iowa Underground, LLC InfraSources Construction, LLC IUC ILLINOIS, LLC IUC Nebraska, LLC QS Mats			Delaware
InfraSource Services, LLC			Delaware


InfrasSource Pipeline Construction, LLC			Delaware
Integracion Tecnologica del Peru, SAC			Peru
Intermountain Electric, Inc. Grand Electric Inc. IM Electric, Inc. Ime Electric Intermountain Electric, Inc. which will do business in California as: Colorado IM Electric Intermountain Electric, Inc., A Corporation of Colorado			Colorado
IonEarth, LLC			Michigan
Irby Construction Company Irby Construction Company, Inc. Legend Foundation Services Marathon Construction Services			Mississippi
Irbyvalard, LLC			Delaware
Island Mechanical Corporation			Hawaii
J&R Underground LLC			Wisconsin
J.C.R. Construction Co., Inc. J.C.R. Utility Construction Co.			New Hampshire
J.W. Didado Electric, LLC			Delaware
JBT Electric, LLC			Texas
Lazy Q Ranch, LLC DE Lazy Q Ranch, LLC (De) Lazy Q Ranch, LLC			Delaware
Lee Electrical Construction, LLC Lee Utilities, Inc.			North Carolina
Lex Engineering Ltd.			British Columbia
Lindsey Electric, L.P.			Texas
LUMA College for Technical Training, LLC			Puerto Rico
M. G. Dyess, LLC			Mississippi
M. J. Electric, LLC Great Lakes Line Builders Iron Mountain M.J. Electric, LLC IRON POWER SERVICES, A DIVISION OF M. .J ELECTRIC Iron Power Services Iron Power Services, A Division of M.J. Electric, LLC M. J. Electric, LLC – Iron Mountain M. J. Electric, LLC DBA M. J. Electric Iron Mountain, LLC M. J. ELECTRIC, LLC IRON MOUNTAIN M.J. Electric, LLC DBA M.J. Electric Iron Mountain M.J. Electric, LLC Iron Mountain M.J. Drilling, A Division of M. J. Electric M.J. Drilling, A Division of M. J. Electric, LLC MJ Excavating, A Division of M.J.Electric, LLC Process Controls & Instrumentation Process Controls & Instrumentation, A Division of M. J. Electric,LLC			Delaware
MATG I, LLC			Delaware
Mears Canada Corp.			Nova Scotia
Mears Equipment Services, LLC Infrasource Of Pa, LLC Mears Equipment Service, LLC QPS Global Services			Delaware
Mears Group Pty Ltd			Australia
Mears Group, Inc. De Mears Group De Mears Group, Inc. Enscope Ranger Directional			Delaware


Mears Holdings, LLC Mears Holdings Ny, LLC TN Mears Holdings, LLC			Delaware
Mears Installation, LLC			Delaware
Mearsmex S. de R.L. de C.V.			Mexico
Mejia Personnel Services, LLC			Texas
Microline Technology Corporation			Michigan
Mid America Energy Services, Inc. TA Construction Tom Allen Construction Company Inc. Tom Allen Construction Company of Delaware			Delaware
MTS Quanta, LLC Mercer Technical Services MTS Field Services MTS Field Services (Richmond Co)			Texas
NACAP Niugini Ltd.			Papua New Guinea
Nacap PNG Limited			Papua New Guinea
Nacap Pty Ltd.			Australia
NLC CA., Inc. NORTHWEST LINEMAN COLLEGE			Idaho
NLC FL., Inc. Northwest Lineman Center			Idaho
NLC ID., Inc. Northwest Lineman College			Idaho
NLC TX., Inc. Northwest Lineman Center Northwest Lineman Training Center Northwest Lineman Training Center, Inc.			Idaho
North Houston Pole Line, L.P. North Houston Pole Line Limited Partnership QUANTA FOUNDATION SERVICES			Texas
Northern Powerline Constructors, Inc. Chatham Electric			Alaska
NorthStar Energy Services, Inc. NC Northstar Energy Services, Inc Quanta Underground Services Quanta Underground Services (Culpeper Co) Quanta Underground Services (Spotsylvania Co) Quanta Underground Services, Inc. North Star Energy, LLC			North Carolina
Northstar Energy Solutions, LLC			Delaware
Nova Constructors LLC			Japan
Nova Equipment Leasing, LLC			Washington
Nova Group, Inc. NGI Construction NGI Construction, Inc. NGI Construction, Inc. (FN) Nova Group, Inc Nova Group, Inc (CA) Nova Group, Inc. DBA NGI Construction			California
Nova NextGen Solutions, LLC			Delaware
NPC Energy Services LLC			Alaska
O. J. Pipelines Canada Corporation O.J. Pipelines Canada O.J. Industrial Maintenance			New Brunswick


O. J. Pipelines Canada Limited Partnership OJ Industrial Maintenance OJ Pipelines Canada			Alberta
One Call Locators Canada Ltd.			Canada
P.J. Helicopters, Inc.			California
PAR Electrical Contractors, LLC Computapole Didado Utility Company, Inc. J.W. Didado Electric J.W. Didado Electric, Inc. Longfellow Drilling Riggin & Diggin Line Construction Seaward Seaward Corp			Missouri
Par Internacional, S. de R.L. de C.V.			Mexico
PAR Western Line Contractors , LLC QUES Utility Line Management Services			Delaware
Performance Energy Services Guyana, Ltd.			British Virgin Islands
Performance Energy Services, L.L.C.			Louisiana
Phasor Engineering Inc.			Alberta
Phoenix North Constructors Inc.			British Columbia
Phoenix Power Group, Inc.			Delaware
Potelco, Inc. Potelco, Incorporated			Washington
Power Delivery Program, Inc.			Idaho
Price Gregory International, LLC			Delaware
Price Gregory Services, LLC			Delaware
Probst Electric, Inc. Advanced Electric Systems Probst Construction, Inc. Utility Fleet Services			Utah
QEPC Power Solutions, LLC			Delaware
QES GP, LLC			Delaware
QP Energy Services, LLC			Delaware
QPS Engineering, LLC QPS Engineering PLLC QPS Environmental QPS Global QPS Global Services QPS Global Services (Richmond Ci) QPSE			Delaware
QPS Engineering, Ltd. Quanta Inspection Services Quanta Resource Development			Alberta
QPS Flint, LLC QPS Flint Construction QPS Flint Tank Services QPS Professional Services Quanta Environmental Solutions Quanta EPC Services Quanta Tank Services			Delaware
QSI Engineering, Inc.			Delaware
QSI Finance (Australia) Pty Ltd.			Australia


QSI Finance (Cayman) Pvt. Ltd.			Cayman Islands
QSI Finance Canada ULC			British Columbia
QSI Finance GP (US), LLC			Delaware
QSI Finance I (US), LP			Delaware
QSI Finance II (Australia) Pty Ltd.			Australia
QSI Finance II (Lux) S.à r.l			Luxembourg
QSI Finance III (Canada) ULC			British Columbia
QSI Finance III (Lux) SARL			Luxemburg
QSI Finance IV (Canada) ULC			British Columbia
QSI Finance IX (Canada) Limited Partnership			British Columbia
QSI Finance V (US), L.P.			Delaware
QSI Finance VI (Canada) ULC			British Columbia
QSI Finance VII (Canada) Limited Partnership			British Columbia
QSI Finance VIII (Canada) ULC			British Columbia
QSI Finance X (Canada) ULC			British Columbia
QSI Holdings I (Singapore) Pte. Ltd.			Singapore
QSI Holdings II (Singapore) Pte. Ltd.			Singapore
QSI Investment VFD, LLC			Delaware
QSI Investment West, LLC			Delaware
QSI Management, LLC			Delaware
QSI, Inc. De Qsi Inc. Qsi, Inc. Of Delaware			Delaware
QSN Lux Holdings I SCSp			Luxembourg
QSN Lux Holdings II SCSp			Luxembourg
QSN Lux Holdings III SCSp			Luxembourg
QSN Lux Holdings IV SCSp			Luxembourg
QTSL, LLC			Delaware
Quanta Asset Management LLC			Delaware
Quanta Associates, L.P.			Texas
Quanta Aviation Equipment Company, LLC			Delaware
Quanta Aviation Services, LLC			Delaware
Quanta Canada GP ULC			British Columbia
Quanta Canada Holdings III Limited Partnership			British Columbia
Quanta Canada Holdings LP			Alberta
Quanta Canada III GP Ltd.			British Columbia
Quanta Capital GP, LLC			Delaware
Quanta Capital LP, L.P.			Delaware
Quanta Capital Solutions, LLC			Delaware
Quanta Cares			Texas
Quanta East, LLC			Delaware
Quanta Electric Power Services West, LLC			Delaware
Quanta Electric Power Services, LLC			Delaware
Quanta Energized Innovations Ltd.			British Columbia
Quanta Energized Services of Canada Ltd.			British Columbia
Quanta Energized Services U.S., LLC			Delaware
Quanta Energy Services, LLC			Delaware


Quanta Environmental, LLC			Delaware
Quanta Equipment Company Canada GP Ltd.			Alberta
Quanta Equipment Company Canada Limited Partnership			Alberta
Quanta Equipment Company, LLC			Delaware
Quanta Government Solutions, Inc.			Delaware
Quanta Infraestructura de Chile SpA			Chile
Quanta Infrastructure Holdings, LLC			Delaware
Quanta Infrastructure Services, LLC			Delaware
Quanta Infrastructure Services, S. de R.L. de C.V.			Mexico
Quanta Infrastructure Solutions Group, LLC Iron Power Services QEPC Timken Power Systems GS			Delaware
Quanta Inline Devices, LLC			Texas
Quanta Insurance Company, Inc.			Texas
Quanta International Holdings (US) LLC			Delaware
Quanta International Holdings II, Ltd.			British Virgin Islands
Quanta International Holdings IV, Ltd.			British Virgin Islands
Quanta International Holdings V Ltd.			British Virgin Islands
Quanta International Holdings VI Ltd.			British Virgin Islands
Quanta International Holdings VII, Ltd.			British Virgin Islands
Quanta International Holdings, Ltd.			British Virgin Islands
Quanta International Limited			British Virgin Islands
Quanta Kingsvale LP Ltd.			British Columbia
Quanta Lines Pty Ltd.			Australia
Quanta Marine Services, LLC			Delaware
Quanta Mountain West, LLC			Delaware
Quanta Power Australia Pty Ltd			Australia
Quanta Power Delivery, LLC			Delaware
Quanta Power Generation, Inc.			Delaware
Quanta Power Solutions India Private Limited			India
Quanta Services Australia Pty Ltd.			Australia
Quanta Services Chile SpA			Chile
Quanta Services Colombia S.A.S.			Colombia
Quanta Services Costa Rica, Ltda.			Costa Rica
Quanta Services Guatemala, Ltda.			Guatemala
Quanta Services International Holdings II Limited Partnership			British Columbia
Quanta Services International Holdings LP			Alberta
Quanta Services Management Partnership, L.P.			Texas
Quanta Services Netherlands B.V.			Netherlands
Quanta Services of Canada Ltd.			British Columbia
Quanta Services Peru S.A.C.			Peru
Quanta Services Puerto Rico Holdings, LLC			Delaware
Quanta Services Solutions PR, LLC Quanta Services Puerto Rico			Puerto Rico
Quanta Services STPR, LLC Quanta Services Puerto Rico			Puerto Rico
Quanta Subsurface Canada, Ltd.			British Columbia


Quanta Technology Canada ULC			British Columbia
Quanta Technology UK Ltd.			United Kingdom
Quanta Technology, LLC Delaware Quanta Technology, LLC			Delaware
Quanta Tecnología do Brasil Ltda.			Brazil
Quanta Telecommunication Solutions, LLC Quanta Telecom Quanta Telecom Services Quanta Telecommunication Services Quanta Telecommunications Services, LLC			Delaware
Quanta Utility Installation Company, Inc.			Delaware
Quanta Utility Operations PR, LLC			Puerto Rico
Quanta Utility Operations, LLC			Delaware
Quanta West, LLC			Delaware
Quanta Workforce Solutions, LLC			Delaware
Quanta-DCO NJ Green Link, LLC			Delaware
R. R. Cassidy, Inc.			Louisiana
Realtime Engineers, Inc.			Delaware
Realtime Utility Engineers, Inc. Infrasource Engineering Company, PC			Wisconsin
Redes Andinas de Comunicaciones S.R.L.			Peru
RMS Holdings, LLC RMS Holdings, LLC (Delaware) RMS Welding Systems Rms Welding Systems LLC RMS Welding Systems LLC RMS Welding Systems, LLC Rms Welding, LLC			Delaware
Road Bore Corporation			Hawaii
Robinson Brothers Construction, LLC			Delaware
Service Electric Company P.D.G. Electric Service EC (DE), Inc. Service Electric Company (DE) Service Electric Company of Delaware Service Electric Company Of Delaware Service Electric Company, Inc.			Delaware
Servicios de Infraestructura del Peru S.A.C.			Peru
Servicios Par Electric, S. de R.L. de C.V.			Mexico
Southwest Trenching Company, Inc.			Texas
Specialty Tank Services, Ltd. Specialty Tank Services Limited Partnership Specialty Tank Services, L.P. Specialty Tank Services, Limited Partnership Specialty Tank Services, LP Specialty Tank Services, Ltd. (LP) Specialty Tank Services, Ltd. Limited Partnership Specialty Tank Services, Ltd. LP Specialty Tank Services, Ltd., L.P. Specialty Tank Services, Ltd., LP Texas Specialty Tank Services, Ltd. LP			Texas
Stronghold General, LLC			Texas
Stronghold Holdings (BVI) Limited			British Virgin Islands


Stronghold Inspection, Ltd. Stronghold Inspection Limited Partnership Stronghold Inspection Ltd, L.P. Stronghold Inspection, L.P. Stronghold Inspection, Limited Partnership Stronghold Inspection, Ltd. Limited Partnership Stronghold Inspection, Ltd., L.P.			Texas
Stronghold Specialty General, LLC			Texas
Stronghold Specialty, Ltd. Stronghold Specialty, Ltd. Limited Partnership			Texas
Stronghold Tower Group, Ltd. Stronghold Tower Group, LP Stronghold Tower Group, Ltd, LP Stronghold Tower Group, Ltd., LP			Texas
Stronghold VI, LLC			U.S. Virgin Islands
Stronghold, Ltd. Stronghold Management Holdings, LP Stronghold, Limited Partnership Stronghold, Ltd. Limited Partnership			Texas
Subterra Damage Prevention Specialists Ltd.			Canada
Summit Line Construction, Inc. Summit Line Construction			Utah
Sumter Utilities, Inc.			Delaware
T. G. Mercer Consulting Services, Inc.			Texas
TC Infrastructure Services Ltd.			British Columbia
The Aspen Utility Company, LLC The Aspen Utility Company, LLC			Texas
The ComTran Group, Inc.			Georgia
The Hallen Construction Co., Inc.			New York
The Ryan Company, Inc. Ryan Company, Inc. of Massachusetts Ryan Company, Inc.(The) Ryan Company, Inc., The The Massachusetts Ryan Company, Inc. The Ryan Company Inc Of Massachusetts The Ryan Company Inc of Massachusetts The Ryan Company Incorporated of Massachusetts The Ryan Company Incorporated Of Massachusetts The Ryan Company Of Massachusetts, Inc. The Ryan Company of Massachusetts The Ryan Company of Massachusetts (FN) The Ryan Company of Massachusetts, Inc. The Ryan Company, Inc. (Massachusetts) The Ryan Company, Inc. of Massachusetts The Ryan Company, Incorporated Electrical Contractors			Massachusetts
TurnKey Automation, Ltd. TurnKey Automation Limited Partnership TurnKey Automation, Limited Partnership Turnkey Automation, Ltd. L.P. TurnKey Automation, Ltd. Limited Partnership Turnkey Automation, Ltd. LP. TurnKey Automation, Ltd., Limited Partnership TurnKey I&E, Ltd.			Texas
Underground Construction Co., Inc. Delaware Underground Construction Co. Ucc - Underground Construction Co. UCC Underground Construction Co., Inc. Underground Construction Co., Inc. (Delaware)			Delaware


Underground Electric Construction Company, LLC			Delaware
Utility Training Services Corporation			Idaho
Valard Construction (Ontario) Ltd.			Ontario
Valard Construction (Quebec) Inc.			Quebec
Valard Construction 2008 Ltd.			Alberta
Valard Construction Australia Pty Ltd.			Australia
Valard Construction LP			Alberta
Valard Construction, LLC Valard			Delaware
Valard Equipment (AB) Ltd.			British Columbia
Valard Equipment GP Ltd.			Alberta
Valard Equipment Limited Partnership			Alberta
Valard Geomatics BC, Ltd.			British Columbia
Valard Geomatics Ltd.			Alberta
Valard Mechanical Ltd.			British Columbia
William E. Groves Construction, LLC Groves Electrical Services			Kentucky
Winco, Inc. Winco Powerline Services Winco Powerline Services Inc. Winco Powerline Services, Inc. Winco, Inc. an Oregon Based Corporation Winco, Inc. D/B/A Winco Powerline Services Winco, Inc. DBA Winco Services Inc. Winco Helicopters			Oregon