A&B Environmental Services - TX, USA

A. Epstein and Sons International - IL, USA

Abate Engineering - NY, USA

Abrahamson & Associates - TX, USA

Ackman, Phillip - CA, USA

Adams Consulting Engineers, Inc. - TX, USA

Adena Utilities Engineering, Inc. - OH, USA

Adica Consulting LLC - IL, USA

ADS Environmental Services - AL, USA

Advanced Engineering - VA, USA

Advanced GeoServices Corp - PA, USA

Advanced Infrastructure Management, - CA,

AECOM Technology Corporation - CA, USA

AES Engineering, Inc. - WI, USA

AES, Ltd. - MS, USA

Aires Consulting Group, Inc. - IL, USA

Alaimo, Richard A. Associates - NJ, USA

Alan J Flood - FL, USA

Alan Plummer Associates - TX, USA

Alexander Engineering, Inc. - TX, USA

Allen & Major Associates, Inc. - MA, USA

Allen & Shariff Corp. - MD, USA

Alpine Technology Inc. - TX, USA

Alvord, Burdick & Howson - IL, USA

AMEC Infrastructure - AZ, USA

Anderson Engineering, Inc. - MO, USA

Andrew & Kuske Consulting Engrs. - NC, USA

Anjou-Recherche/Veolia Water - FRANCE

Appian Consulting Engrs. - NC, USA

Applied Water Mgmt. Inc./ E'town Co - NJ, USA

AquaPoint - MA, USA

ARCADIS Geraghty & Miller, Inc. - CO, USA

Archer Engineers - MO, USA

AREA Environmental - CA, USA

Arizona State University/Enviro eng - AZ, USA

ARM Group, Inc. - PA, USA

ARM Group, Inc. - PA, USA

Armentrout, Roebuck & Matheny - GA, USA

Artesian Environmental - CA, USA

ASA Engineering & Surveying, Inc. - GA, USA

Astbury Group - IN, USA

Atkins Benham Inc. - OK, USA

August Mack Environmental, Inc. - IN, USA

Automation Consulting & Education - FL, USA

Averette Engineering - NC, USA

Ayres Associates - WI, USA

Ayres, Lewis, Norris & May Inc. - MI, USA

Aztec Engr. Aztec Engineering - AZ, USA

B&E Jackson & Associates, Inc. - GA, USA

B&R Engineering - AZ, USA

B.A.T. Services - BELGIUM

B.F. Thompson, P.C. - MI, USA

Bahr, Larry - CA, USA

Bain Medina Bain, Inc. - TX, USA

Baird, Hampton & Brown, Inc. - TX, USA

Baker & Lawson, Inc. - TX, USA

Ballinger Consultants - AZ, USA

Bankson Engineers, Inc. - PA, USA

Barge,Waggoner,Sumner & Cannon - TN, USA

Barr Engineering Company - MN, USA

Barr Engineering Company - MN, USA

Batson & Brown - MS, USA

Battelle Columbus Labs - OH, USA

Baxter & Woodman, Inc. - IL, USA

BBS Corp. Consulting Engineers - OH, USA

BCM Engineers - PA, USA

Beardsley Design Associates, P.C. - NY, USA

Bechtel Environmental, Inc. - CA, USA

Bergmann Associates, Inc. - NY, USA

Berryman & Henigar, Inc. - CA, USA

BETA Engineering Inc. - RI, USA

Beveridge & Diamond, PC - DC, USA

Billings & Associates - NM, USA

Bio Reaction Industries - OR, USA

Biochem Technology, Inc. - PA, USA

Biochem Technology, Inc. - PA, USA

Bioscience, Inc. - PA, USA

Biothane Corporation/Tech Services - NJ, USA

Black & Veatch - MO, USA

Black & Veatch Consulting - UNITED KINGDOM

Black & Veatch/South America - BRAZIL

Blasland, Bouck & Lee/ BBL - NY, USA

Bleck Engineering Co., Inc. - IL, USA

Bolton & Menk, Inc. - MN, USA

Booz Allen & Hamilton, Inc. - VA, USA

Borton-Lawson Engineering - PA, USA

Bowen Engineering Corporation - IN, USA

Bowser-Morner Inc. - OH, USA

Boyle Engineering Corp. - CA, USA

Branch Environmental Corp. - NJ, USA

Bridgewater Group, Incorporated - OR, USA

Brooks Hersey & Associates, Inc. - AZ, USA

Brown & Caldwell - CA, USA

Brown & Gay Engineers, Inc. - TX, USA

Brown & Root - PA, USA

Brown & Root Services Asia - AUSTRALIA

Brunzell Associates Ltd. - IL, USA

Bucher, Willis & Ratcliff Corp. - KS, USA

Burgess & Niple - OH, USA

Burns & McDonnell - MO, USA

Burns & Roe - NJ, USA

Bury & Partners, Inc - TX, USA

Byrne & Associates, Inc - TX, USA

C&M/Claunch & Miller, Inc., Engr. - TX, USA

C&S Engineers, Inc. - NY, USA

C.S. Davidson, Inc - PA, USA

Cabe Associates Incorporated - DE, USA

Calgon Carbon Corporation - PA, USA

Caliber Engineering Consultants - SC, USA

California State University - CA, USA

California State University - CA, USA

Camp Dresser & McKee, Inc./CDM - MA, USA

Cardno MBK(Qld)Pty.Ltd./Brisbane - AUSTRALIA

Carollo Engineers - CA, USA

Carollo Engineers - CA, USA

Carter & Burgess Inc. - TX, USA

CDI Corporation - IL, USA

Cedar Corporation - WI, USA

Cemagref - FRANCE

CET Engineering Services, Inc. - PA, USA

CGVL Engineers - TX, USA

CH2M Hill - CANADA

CH2M Hill - CO, USA

CH2M Hill International Ltd. - CO, USA

Chadwick Ecological Consultants - CO, USA

Charter Oak Environmental Services, - CT, USA

Chavond-Barry Engineering - NJ, USA

Chen, Jeffrey J. - CA, USA

Chester Environmental, Inc. - PA, USA

Chiang Patel & Yerby, Inc. - TX, USA

Childress Engineers, Inc - TX, USA

Chirlin & Associates, Inc. - MD, USA

Clark Dietz, Inc. - IL, USA

Clark-Nexsen - VA, USA

Cochrane Associates, Inc. - MA, USA

Coe & Van Loo Consultants, Inc - AZ, USA

Colorado School of Mines/Enviro - CO, USA

Commonwealth Engineers, Inc. - IN, USA

Conde, Inc. - TX, USA

Conservtech - CA, USA

Consoer Townsend Envirodyne /CTE - IL, USA

Consolidated Technologies, Inc./CTI - TN, USA

Corrpro Companies - OH, USA

Coubourn, Linseisen & Ratcliff - TX, USA

Cowhey Gudmundson Leder, Ltd. /CGL - IL, USA

CPE Services, Inc. - NY, USA

CPF Associates Inc. - MD, USA

Crafton Tull & Associates Inc. - OK, USA

CRW Engineering Group - AK, USA

CSA Consulting Engineers - TX, USA

CTE Engineers - IL, USA

Damon S. Williams Associates - AZ, USA

Daniel D. Clinton, Jr. P.E. - TX, USA

David Evans and Associates - OR, USA

Dawson Engineering - AL, USA

Dayton & Knight - CANADA

DDC Engineers, Inc - SC, USA

DHI Water & Environment - DENMARK

Dibble and Assoc. Consulting Engrs. - AZ, USA

DMJM + Harris, Inc. - AZ, USA

Donohue & Assc., Inc. - WI, USA

DOWL Engineers - AK, USA

DSS Consulting, Inc. - GA, USA

Duffield Associates - DE, USA

Duffy, Dolcy and McManus - NJ, USA

Dvirka & Bartilucci Consl. Engrs. - NY, USA

DWG Associates - GA, USA

EA Engineering, Science & Tech - MD, USA

Earth Tech Canada - Head Office - CANADA

Earth Tech Inc. - CA, USA

Ecology and Environment Inc. - NY, USA

ECT/Environmental Consulting & Tech - FL, USA

EDAW - CA, USA

Edward T. Davis & Associates, Inc. - MS, USA

Ekster and Associates - CA, USA

Electrolytic Technologies Corp. - FL, USA

EMA, Inc. - MN, USA

EMH & T - OH, USA

Engineering Enterprises, Inc. - IL, USA

Engineering Solutions Inc. - HI, USA

England-Thims & Miller, Inc. - FL, USA

EnSafe, Inc - TN, USA

ENSR International - MA, USA

Entellus - AZ, USA

Entranco Engineers - AZ, USA

ENTRIX - TX, USA

Enviromega Inc. - CANADA

Environmental Consulting & Technolo - MI, USA

Environmental Engineering & Tech. - VA, USA

Environmental Management Consultant - WA, USA

Environmental Management Consulting - WA, USA

Enviroquip, Inc. - TX, USA

EnviroSim Associates Ltd. - CANADA

EnviroSim Associates Ltd. - USA

Envisors Engineering - FL, USA

ERM - PA, USA

ERTH Inc. - CO, USA

Evans, Kuhn and Associates - AZ, USA

F.E. Jordan Associates, Inc. - CA, USA

Fisher Engineering - PA, USA

Floyd Browne Associates, Inc. - OH, USA

Forcier Aldrich & Associates, Inc - VT, USA

Ford Engineering, Inc. - TX, USA

Foster Wheeler Ltd. - NJ, USA

Foth & Van Dyke - WI, USA

FPS Engineering - OH, USA

FRA Engineering, P.C. - NY, USA

Freese and Nichols, Inc. - TX, USA

FTN Associates - AK, USA

Fuss & O'Neil, Inc. - CT, USA

Gannett Fleming, Inc. - PA, USA

Garver Engineers - AR, USA

GBA/George Butler Associates, Inc. - KS, USA

GE-Intellution - CA, USA

George Butler Associates, Inc. - KS, USA

George Washington University - DC, USA

Geoscience Group, Inc - NC, USA

Geotech, Inc. - KS, USA

Global Environmental Operations - GA, USA

Graef, Anhalt, Schloemer & Assoc. - WI, USA

Gray & Osborne - WA, USA

Greeley & Hansen - IL, USA

Greenman-Pedersen, Inc. - NY, USA

Gresham, Smith and Partners - TN, USA

GRW Engineers, Inc. - KY, USA

GRW Engineers, Inc. - KY, USA

GTA Engineering - AZ, USA

Gwin, Dobson & Foreman Inc. - PA, USA

Hach Company - CO, USA

Hall & Associates - DC, USA

Hallenberger Engineering - TX, USA

Halliburton (Kellog, Brown & Root) - TX, USA

Hartman & Associates, Inc. - FL, USA

Hatch Mott MacDonald - NJ, USA

Hayes, Seay, Mattern & Mattern, Inc - VA, USA

Hayter Engineering - TX, USA

Hazen & Sawyer - NY, USA

HDR Engineering, Inc. - NE, USA

Heller-Weaver & Sheremeta, Inc. - FL, USA

Hendon Engineering - AL, USA

Herbert Chock & Associates, Inc. - HI, USA

HJ Malavet & Associates - PR, USA

HNTB Corp. - MO, USA

Horner&Shifrin, Inc. - MO, USA

Howard Needles Tammen & Bergendorf - IN, USA

Hubbell, Roth & Clark, Inc - MI, USA

Hydromantis Inc. - CANADA

HydroQual, Inc. - NJ, USA

Hydro-Terra, Inc. - MD, USA

I & I Engineering - PA, USA

Illinois Institute of Technology - IL, USA

Indo American Engineering, Inc - WY, USA

Integrated Science & Engineering In - GA, USA

Iowa State University/Engineering - IA, USA

Jacobs-Sirrine Engineering, Inc. - CA, USA

Jacques Whitford Co, Inc. - PA, USA

JMT/Johnson, Mirmirah and Thompson - MD, USA

Johnson & Johnson - PA, USA

Jones & Carter, Inc. - TX, USA

Jones & Henry Engineering Inc - OH, USA

Jordan, Jones & Goulding, Inc. - GA, USA

Kaaterskill Engineering Associates - NY, USA

Katz & Associates Inc, - CA, USA

Kay Kutchins & Associations - TX, USA

Kellard Engineering & Consulting - NY, USA

Keller Consulting Engrs. - PA, USA

Keystone Engineering Group, Inc. - PA, USA

Khafra Engineering Consultants, Inc - GA, USA

Kimball, L.Robert & Associates - PA, USA

Kimley-Horn and Associates - NC, USA

Kimley-Horn and Associates - TX, USA

Kirkham Michael Consulting Engrs. - AZ, USA

Kleinfelder, Inc. - CA, USA

Klingner & Associates, P.C. - IL, USA

Klotz Associates, Inc. - TX, USA

Korea Advanced Inst. Of Science & T - KOREA

Krieger & Stewart, Inc - CA, USA

KS Associates, Inc - OH, USA

Kurtanich Engineers & Assoc, Inc - PA, USA

Larry Walker Assocociates - CA, USA

Larson Design Group, Inc - PA, USA

Law Engineering & Environmental Se - GA, USA

Law Gibb Group - GA, USA

Lawler, Matusky & Skelly Engrs. - NY, USA

LECG - CA, USA

LNV, Inc - TX, USA

Lockwood Greene - SC, USA

Lockwood, Andrews & Newnam, Inc - TX, USA

LopezGarcia Group - TX, USA

Louisiana State University/Enviro - LA, USA

LSC Design, Inc - PA, USA

Lumos and Associates, Inc. - NV, USA

Lund Tekniska Hagskola - SWEDEN

Mactec Engineering and Consulting, - GA, USA

MACTEC(Law Cos. Group) - GA, USA

Malcolm Pirnie, Inc. - NY, USA

Mallett & Associates, Inc. - GA, USA

Martin/Martin, Inc. - CA, USA

Martin/Martin, Inc. - MO, USA

Maser Consulting, PA - NJ, USA

McDonough Associates Inc. - IL, USA

McKim & Creed - NC, USA

Mead & Hunt, Inc - WI, USA

MEC /Midwest Environmental Consult - MO, USA

MEC-Weston Analytical Systems Inc. - CA, USA

Metcalf & Eddy, Inc. - MA, USA

Meyer, Meyer, LaCroix & Hixson, Inc - LA, USA

MFRA - MN, USA

MHB Paradigm Design, Inc. - MI, USA

Michael Baker Corporation - PA, USA

Michael Baker Corporation - PA, USA

Michael E Doczi & Associates - VA, USA

Michael Ernst, P.E., P.A. - NJ, USA

Midwestern Consulting, LLC. - MI, USA

Millenium Science & Engineering Inc - VA, USA

MMM Design Group - VA, USA

MMS Consultants Inc. - IA, USA

Moreno Cardenas, Inc. - TX, USA

Morrison-Maierle, Inc. - AZ, USA

MSA Professional Services, Inc - WI, USA

MSA, P.C. - VA, USA

Murfee Engineering - TX, USA

MWH/Montgomery Watson Harza - CO, USA

MWH/Montgomery Watson Harza - CO, USA

National Pingtung U. of Science & E - TAIWAN

National Small Flows Clearinghouse - WV, USA

Nolasco & Associates - ARGENTINA

North Carolina State University - NC, USA

Northwest Engineering, Inc - PA, USA

northwest hydraulic consultants Ltd - CANADA

Norvell and Poe Engineers - TN, USA

NRS Consulting Engineers - TX, USA

NTH Consultants, Ltd. - MI, USA

Nussbaumer & Clarke, Inc. - NY, USA

N-Y Associates - LA, USA

O'Brien & Gere Engineers, Inc. - NY, USA

Oller Engineering, Inc - TX, USA

O'Malley Engineers, LLP - TX, USA

Ondeo Degremont - VA, USA

On-Site Systems, Inc. - TN, USA

Oregon State University - OR, USA

ORSANCO - OH, USA

Osborn Engineering Company - OH, USA

PA Consulting Group - DC, USA

Pape-Dawson Engineers - TX, USA

Parkhill, Smith & Cooper - TX, USA

Parsons - CA, USA

Parsons Brinckerhoff - OR, USA

Parsons Brinckerhoff Quade Inc. - NY, USA

Parsons Brinkerhoff Quade & Douglas - VA, USA

Parsons International Limited - UNITED ARAB EMIRATES

Pate Engineers - TX, USA

Patrick Engineering Associates - GA, USA

PBS&J - CA, USA

PBS&J - FL, USA

PDC, Inc. - AK, USA

Pedersen & Pedersen, Inc - PA, USA

Pehrson Associates - GA, USA

Pennoni Associates, Inc - PA, USA

Peratrovich, Nottingham & Drage/PND - AK, USA

Pettit, Inc. - CA, USA

Pierce, Goodwin, Alexander & Linvil - TX, USA

PMA Consultants - AZ, USA

Potesta & Associates, Inc - WV, USA

Power Engineers - ID, USA

Prack Consult GmbH - GERMANY

Precision Technik, Inc. - GA, USA

Primatech LLC - AZ, USA

Professional Engineering Consultant - KS, USA

Professional Operations, Inc. - TX, USA

Project Engineering Consultants - AZ, USA

PSI-Professional Service Industries - IL, USA

Rau and Associates, Inc. - CA, USA

Rayburn Cherry Engineers, Inc. - TX, USA

RBA Engineers, Inc. - AK, USA

RBF Consulting - CA,

Redmon Engineering - WI, USA

Respirtek, Inc. - MS, USA

Rezek, Henry, Meisenheimer & Gende, - IL, USA

Rick Engineering Company - AZ, USA

Rickmond Engineering, Inc. - VA, USA

Ridolfi Engineers, Inc - WA, USA

Ritoch-Power & Associates - AZ, USA

RJN Group, Inc - IL, USA

RMC Engineering - CA, USA

Robert G. Barrilleaux & Assoc., Inc - LA, USA

Robert G. Hamilton Consulting engr. - IL, USA

Robert M. Sutherland, P.C. - NY, USA

Roth Hill Engineering Partners - WA, USA

Rothberg,Tamburini, and Winsor/ RTW - CO, USA

RQBD Engineering Consultants - PA, USA

Ruekert & Mielke, Inc - WI, USA

Rummel, Klepper & Kahl (RK&K) - MD, USA

Rutgers University/Enviro Sciences - PA, USA

S&B Infrastructure, Ltd - TX, USA

Sagamore Environmental Services, In - IN, USA

Sandia National Laboratories - NM, USA

Santec Consulting Ltd. - CANADA

Sardar Vallabhbhai Patel Institute - INDIA

Savin Engineers, P.C. - NY, USA

Schaumburg & Polk, Inc. - TX, USA

Schiess & Assc. , Consulting Engrs. - ID, USA

Sear-Brown - NY, USA

Sebesta Blomberg & Assc., Inc. - MN, USA

Separations Consultants Inc. - CA, USA

Severn Trent Labs - UNITED KINGDOM

Shapiro Engineering - NV, USA

Shaw Environmental Inc. - NJ, USA

Sidhi Consultants, Inc. - CA, USA

Smith Seckman Reid, Inc - TN, USA

Southwest Engineers, Inc. - TX, USA

Spalding DeDecker Associates, Inc. - MI, USA

Spotts, Stevens & McCoy, Inc - PA, USA

SSOE, Inc - OH, USA

Stantec Consulting Ltd. - CANADA

Stearns & Wheler - NY, USA

Stormwater Management Inc. - OR, USA

Stowa - NETHERLANDS

Strand Associates Inc - WI, USA

Strand Associates, Inc - KY, USA

Strickland Engineering, L.C. - MO, USA

Sundquist Engineering, Inc. - IN, USA

Superior Engineering - WI, USA

SuperSystems, Inc. - CA, USA

Synagro - TX, USA

Systech Engineering, Inc - CA, USA

TAI Environmental Sciences - AL, USA

Tank Industry Consultants - IN, USA

Tap Resource Development Group - CO, USA

Taylor Engineers, Inc. - ID, USA

TBE Group, Inc. - FL, USA

Teague, Nall & Perkins, Inc - TX, USA

Teague, Nall & Perkins, Inc. - TX, USA

Technische Universitat Berlin - GERMANY

Tectonic Engineering - NY, USA

Terracon - KS, USA

Testing Engineers & Consultants - MI, USA

Tetra Tech, Inc - CA, USA

The Advent Group - CO, USA

The Dewberry Companies - VA, USA

The EADS Group - PA, USA

The Larkin Group - MO, USA

The Louis Berger Group, Inc. (LBG) - NJ, USA

The Sear-Brown Group, Inc. - NY, USA

TheCentrifugeGuy.com - PA, USA

Thomas & Hutton Engineering Co. - SC, USA

Thompson Engineering - AL, USA

TIMMONS - VA, USA

Tokyo Metropolitan Govt/Dept Sewage - JAPAN

Transystems Corporation - TX, USA

TRC Customer-Focused Solutions - CT, USA

TRC Omni Environmental Corporation - NJ, USA

Trinity Consultants, Inc. - TX, USA

Tutela Engineering Associates Inc. - MA, USA

Tysinger,Hampton & Partners - TN, USA

U. of Illinois at Urbana-Champaign - IL, USA

U.S. Army Engineer Research & Devel - IL, USA

U.S. Bureau of Reclamation - AZ, USA

U.S. Bureau of Reclamation - CO, USA

Ujacobs.S. EPA - DC, USA

Uni-tec Consulting Engineers - MD, USA

Unitech Engineering - PA, USA

University of Arizona - AZ, USA

University of California - Berkeley - CA, USA

University of Central Florida - FL, USA

University of Cincinnati - OH, USA

University of Hawaii - HI, USA

University of Manitoba - CANADA

University of Maryland Eastern Shor - MD, USA

University of Nebraska - Lincoln, - NE, USA

University of Western Ontario - CANADA

University of Wisconsin - Madison - WI, USA

URS Corporation - CA, USA

Van de Weile Engineering - TX, USA

Velvin & Weeks Consulting Engrs. - TX, USA

Veolia Water / Anjou Recherche - IL, FRANCE

Veolia Water N. America (USFilter) - TX, USA

Vickery & Associates, Inc - TX, USA

Virginia Polytechnic Institute - VA, USA

Viro Group/Resource Solutions - FL, USA

Vivendi/US Filter/ Veolia Water - PA, USA

Volkert & Associates, Inc. - AL, USA

W.C. Cammett Engineering, Inc. - MA, USA

Wade- Trim - MI, USA

Waldemar S. Nelson & Company - LA, USA

Wantman Group, Inc. - FL, USA

Washington University - MO, USA

WATEK Engineering Corp. - MD, USA

Water Environment Federation - VA, USA

Water Systems Technical Serv./WSTS - AZ, USA

Water3 Engineering, Inc. - CA, USA

Webster Environmental Engineering - KY, USA

Westin Engineering, Inc - MI, USA

Weston & Sampson Engineers - MA, USA

Weston Solutions, Inc. - PA, USA

Whitley Burchett & Associates - CA, USA

Whitman, Requardt & Associates - MD, USA

Widseth Smith Nolting & Assoc., Inc - MN, USA

Wight & Company - IL, USA

Wiley & Wilson, Inc - VA, USA

Wilson & Co., Engineers, Architects - AZ, USA

Wink, Inc. - LA, USA

Woodruff & Howe Enviro Engineering, - GA, USA

Woodward & Curran, Inc - IL, USA

Wright-Pierce - ME, USA

WSB & Associates, Inc. - MN, USA

XCG Consultants Ltd. - CANADA

Yost and Gardner Engineers - AZ, USA

Zebra-Tech - NY, USA