OUR TEAM

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hands on technical knowledge

Sara Martin, P.E.

Sara Martin, P.E.

Principal & Owner

Kirsten Cerro, P.E.

Kirsten Cerro, P.E.

Managing Director

Mark Greene, PH.D.

Mark Greene, PH.D.

Sr. Technical Director

John Whalen

John Whalen

Sr. Project Manager

Andre McClain

Andre McClain

Construction Inspection

Sue Perriello, P.E.

Sue Perriello, P.E.

Project Engineer

Zach Dineen

Zach Dineen

Project Engineer

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extensive knowledge

about our team

Sara Martin, P.E.

Sara Martin, P.E.

Principal & Owner

Sara Martin is a licensed professional engineer with over 20 years of experience in project development, management and design of various municipal and industrial water, wastewater, and utilities projects. Her experience also includes design-build implementation, start-up, operation and troubleshooting of anaerobic and aerobic wastewater treatment systems.

Before starting Critical Path Engineering Solutions, Sara worked previously at O’Brien & Gere Engineers (now Ramboll) for most of her career, one of the leading consulting firms in these services.

Sara Martin has a diverse experience background with the ability to take a project from initial concept through design and implementation, including bench-scale treatability, pilot studies and project scale-up.

Her diverse experience also includes subject matter expertise, specializing in complete life cycle project review and guidance of wastewater process treatment design, construction, and start-up activities.

Over the years, Sara has developed working relationships with various experts, technology providers and consulting professionals in water and wastewater treatment design. This combined expertise will still be utilized through partnerships on projects, to guarantee a delivery of quality projects to clients.

Kirsten Cerro, P.E.

Kirsten Cerro, P.E.

Managing Director

With a diverse 22-year career, Kirsten brings project management expertise and leadership experience to every assignment she engages in.

As a project manager, she has worked with multiple different engineering teams, designing and managing large, multi-disciplinary projects for airports, public facilities, higher education and K-12 facilities, and telecommunications companies. In addition to her infrastructure expertise, she brings vertical facilities design knowledge to the team from projects encompassing architectural, structural, mechanical, electrical, and life safety design. She has managed multiple award-winning projects, including one ACEC-NY Diamond Award for Engineering Excellence, and three Platinum Awards.

Kirsten has held multiple board and voluntary positions with her previous employer, and currently is in her 3rd year as a board member with the New York Aviation Management Association, representing over 13,000 members and 120 airports in New York State. Kirsten holds an M.B.A. from the University at Buffalo, and a B.S. in civil engineering from Clarkson University.

Mark Greene, PH.D.

Mark Greene, PH.D.

Sr. Technical Director

Dr. Greene has extensive professional experience with wastewater treatment, industrial pretreatment, and biosolids handling applications. His areas of technical expertise include biological wastewater treatment, including process optimization, energy neutral operation, nutrient removal, and membranes; solids handling technologies, including anaerobic digestion, combined heat and power, thickening and dewatering; disinfection; and process modeling. Dr. Greene is experienced in the areas of municipal and industrial wastewater treatment, anaerobic digestion for biosolids and high-strength industrial wastewater, as well as environmental process research and development. He has performed original research, project management, technical guidance, feasibility evaluations, treatability studies, field demonstrations, full-scale start-ups, computer modeling and process troubleshooting.

John Whalen

John Whalen

Sr. Project Manager

John Whalen is a professional engineer with 28 years of experience in construction/project management and civil/environmental engineering/construction. Expertise in wastewater treatment plant construction, geotechnical construction, landfill capping, dredging, and utility construction. Liaison between federal/state/local government officials, client representatives, design engineers, and site contractors. Versed in regulatory compliance issues, site assessments, corrective action planning, and procedural development.

Andre McClain

Andre McClain

Construction Inspection

Andre McClain has over 20 years of experience in construction inspection work. Andre has OSHA and DOT training and certification and has experience in all types of construction including new pipe installation, sewer lining and pipe rehabilitation, wastewater treatment plant construction, maintaining project environmental compliance at state and federal level, and green infrastructure projects.

Sue Perriello, P.E.

Sue Perriello, P.E.

Project Engineer

Sue Perriello is a licensed professional engineer with over 20 years of experience in project management. She has a variety of experience in the analysis of wastewater data, alternatives evaluation, energy audits, permitting, and construction observation.

Zach Dineen

Zach Dineen

Project Engineer

Zach brings 25+ years of engineering, project management and construction management experience to Critical Path. Zach is a retired U.S. Air Force Civil Engineering Squadron Commander where he has experience in vertical and horizontal construction methods and execution. Along with his military experience, Zach brings his knowledge of engineering mechanical building systems and designs, estimating, project planning and execution to Critical Path. Additionally, Zach is an Assistant Professor at SUNY O.C.C. where he teaches Construction Management and Engineering Technology. Zach has an A.A.S. from SUNY O.C.C. in Engineering Science, a B.S. from Syracuse University in Mechanical Engineering and a M.E. from Iowa State University in Systems Engineering.