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Our Team:




                                                  William C. (Bill) Siegel, PE





Mr. Siegel is a proven business leader, with a track record of driving profitable growth and expansion.  His past experience includes serving as CEO and Chairman of the Board of an approx. $400M revenue science and engineering consulting firm where he developed and executed a successful strategy to diversify and expand globally.


Mr. Siegel recently founded several companies including McMahon|Siegel Group, WS Group International LLC, and William Siegel Consultants (to provide technical services where an LLC is not allowed) to serve the A/E/C and related industries with specialty consulting in areas such as Mergers and Acquisitions, operational reviews, Board service, and executive consultation.  Mr. Siegel is also a founder of Colergo (, an industry changing B2B internet startup helping peer firms share resources and maximize profit.  He sits on the Boards and/or is a paid advisor for multiple companies in the A/E/C industry.


Within the A/E/C industry Mr. Siegel is a recognized leader, regularly presenting at gatherings and conferences, and having been selected by his peers for industry leadership roles.  Further, he is an accomplished engineer with numerous published papers and presentations.  He is well known for his exceptional skills with regard to strategy, mergers and acquisitions (having successfully completed 20 acquisitions in his career), and client relations and project management.  Finally, Mr. Siegel is an experienced Board member and serves on multiple for-profit Boards, and is actively involved with several non-profit organizations and his professional and personal communities overall. 



                                    Kevin J. McMahon





Kevin J. McMahon became Group Vice President, Asia in January 2014 following Jacobs’ acquisition of SKM, which Jacobs completed in December 2013. He joined Jacobs in 2007 when Jacobs acquired Edwards and Kelcey, a major North American Engineering Firm where he was Chairman and CEO. Since joining Jacobs, Kevin has increased market penetration, profitability and growth. As Group Vice President, North American Infrastructure through 2013, he oversaw major projects for highways, rail, aviation, telecom, water and utility clients. Kevin currently oversees major projects in Asia including Singapore, Malaysia, Indonesia, China, Thailand, Hong Kong and the Philippines. Jacobs projects in Asia are diverse and include major capital expenditures in the chemicals, oil and gas, pharmaceutical, power, infrastructure and mining sectors.


Kevin graduated magna cum laude from Seton Hall University with an MBA in International Business. He received the university’s W. Paul Stillman School of Business Leadership Award. Kevin earned his Bachelor of Science degree in Economics at the State University of New York. He also completed the Harvard Business School’s Executive Education Program on Leading Professional Service Firms. A member of Beta Gamma Sigma, the National Honor Society for Business, Kevin is listed in Who’s Who Worldwide, and is active in many engineering and construction industry associations. He is a member of The Moles, a prestigious heavy underground construction group founded in 1936. In 2006, he received the “Distinguished Citizen Award” from the Patriots’ Path Council of the Boy Scouts of America.

                                         Russell E. Erbes





Mr. Erbes is a Certified Consulting Meteorologist, and former Chief Technical Officer (CTO) of a major science and engineering consulting firm.  As CTO Mr. Erbes was responsible for developing and implementing Quality Management Programs that met a wide variety of client demands, up to and including NQA-1.  He was also responsible for developing and implementing a technical development career path program for highly skilled professionals who want to advance within the firm but do not want management positions, the so-called Third Dimension of corporate organizations. 


Mr. Erbes has over 40 years of consulting experience, all of which was focused on delivering high quality technical deliverables.  As a practicing consulting scientist, he understands the advantages and disadvantages of Quality Management Programs as practically implemented.  Also, since he personally became an executive of a major technical consulting firm through the technical career path, he understands the complexity of developing and implementing a system for professionals to advance in other than line management positions. 


Mr. Erbes continues to provide air quality consulting services, is a recognized author and lecturer with numerous publications, and has presented at numerous industry and client-based forums.  He is author of the hardcover book A Practical Guide to Air Quality Compliance, Second Edition, published by John Wiley & Sons.

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