- Alex E. Paris Contracting Company
- Babst Calland
- Beveridge & Diamond, P.C.
- Borton-Lawson Engineering
- Bravo Group
- Buchanan, Ingersoll & Rooney, PC
- Civil & Environmental Consultants, Inc.
- Cleveland Brothers Equipment Company
- Cozen O’Connor
- Dawood Engineering, Inc.
- Deloitte LLP
- Duane Morris LLP
- Eckert Seamans Cherin & Mellott, LLC
- Ecosystem Investment Partners
- Endeavor Professional Services
- Environmental Standards, Inc.
- Flex Energy Solutions
- FTI Consulting
- GA BIBIKOS, LLC
- GeoStabilization International
- Geosyntec
- Golder
- GPD Group
- Groundwater & Environmental Services
- Halliburton Energy Services
- Highland Field Services, LLC
- Hunt Valley Environmental, LLC
- K&L Gates
- Larson Design Group
- Manko, Gold, Katcher & Fox
- Markosky Engineering Group, Inc.
- McGuire Woods
- McKim & Creed, Inc.
- McNees Wallace & Nurick, LLC
- Moody & Associates, Inc.
- Mott MacDonald
- National Field Services
- Nemacolin Woodlands Resort
- New Pig Energy
- Overstreet & Nestor, LLC
- Penn Environmental and Remediation, Inc.
- Penn State Hospitality Services
- Pennsylvania One Call System, Inc.
- Post & Schell, P.C.
- Porter Wright Morris & Arthur LLP
- S&T Bank
- Saul Ewing Arnstein & Lehr LLP
- Schlumberger Oilfield Services
- Schneider Downs & Co., Inc.
- SDI Gas LLC
- Shale POWER
- Stahl Sheaffer Engineering
- Steptoe & Johnson PLLC
- Stevens Engineers & Constructors, Inc.
- Tetra Tech, Inc.
- The Gateway Engineers
- The Thrasher Group
- Titan Energy Solutions
- Trinity Consultants, Inc.
- Universal Pressure Pumping, Inc.
- USA Compression
- Waste Management Energy Services
- WSP
