50 Years of Engineering Excellence Brochure

DONALD F. CARLIN, P.E.
Years Of Service 1969-1982
A 1960 graduate of West Virginia University, Don Carlin was a
mining engineer for Gwin, Dobson & Foreman, Inc., specializing in
surface mining engineering. He joined the GD&F Board of
Directors in 1978.
DENNIS P. LINGENFELTER, P.E.
Years Of Service 1973-1991
A Penn State University graduate with a master’s degree from Oklahoma State
University (1973), Denny Lingenfelter was a GD&F environmental engineer
specializing in wastewater treatment and process design. He joined the Board of
Directors in 1984 and served as Vice President and President.
JOHN G. FOREMAN, P.G.
Years Of Service 1981-1987
John Foreman joined the Mineral Industries Division in 1981. A geology graduate of
Edinboro University, he specialized in mine drainage abatement, deep mine
closures and specialized hydrogeology projects for clients throughout the United States.
Foreman joined the Board of Directors in 1985 and served as Secretary-Treasurer.
MARK GLENN, P.E.
Years Of Service 1977-Present
A 1977 graduate of the University of Pittsburgh, Mark Glenn started his
engineering career in the GD&F Clarion office. He has been president and
CEO since 1985. During his tenure, GD&F broadened its capabilities into
transportation, structural and architectural engineering and construction
management. The firm expanded its regional client base to include large
projects throughout Pennsylvania, Maryland and West Virginia. Glenn has
also overseen some of the largest engineering projects in the firm’s history.
1976-1996
GD&F Office Building
2900 Fairway Drive
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