Our Staff

Senior Staff

J. Eric Peterson, P.E.

Senior Associate
Eric Peterson, P.E., is a Senior Associate with Whitlock Dalrymple Poston & Associates, P.C., in the firm’s Manassas, Virginia office where he participates in various structural, material, and architectural engineering activities, specializing in building envelope and façade failures, nondestructive testing, and design and repair of concrete and masonry structures. Mr. Peterson performs forensic field and laboratory investigations, façade and building envelope investigations, corrosion investigations, structural inspection, analysis and design, architectural retrofit and repair, roofing and waterproofing investigations, development of design documents, repair recommendations and expert witness testimony. During his career, Mr. Peterson has been involved with several high profile projects throughout the country.

Prior to joining WDP, Mr. Peterson was a Structural Engineer for Sverdrup Civil, Inc. in Falls Church, Virginia, where he contributed to several large bridge and roadway projects. Mr. Peterson is a licensed civil engineer in Virginia, Maryland, Delaware and New Jersey. Mr. Peterson’s education includes a Master of Science in Civil Engineering in 1993 and a Bachelor of Science in Civil Engineering in 1991 both from Virginia Polytechnic Institute.

Mr. Peterson is a member of several professional organizations, including the American Concrete Institute, the Construction Specifications Institute, the International Concrete Repair Institute, the American Society for Nondestructive Testing, the American Society for Testing and Materials, where he serves on committees C-9 Concrete and Aggregates and E-6 Performance of Buildings, and The Masonry Society, where he serves as Chairman of the Existing Masonry Committee. He has authored several technical papers on construction and testing of concrete and masonry structures.

Robert F. Scheller, P.E.

Associate
Robert Scheller, P.E., is currently an Associate with Whitlock Dalrymple Poston & Associates, P.C., and is involved primarily with the geotechnical engineering department in the firm’s Manassas, Virginia office. He is responsible for technical and fiscal management of geotechnical engineering, materials testing, and construction monitoring activities. Mr. Scheller also oversees the development and management of geotechnical investigations, forensic investigations, expert testimony, construction inspection and laboratory testing programs for commercial, industrial, and residential projects.

Prior to joining WDP in 1997, Mr. Scheller was a Project Engineer with Wall Technologies of the Mid-Atlantic, Inc., in Virginia, where he was responsible for designing earth retention systems, including Newcastle Retaining Walls.

Mr. Scheller’s education includes a Bachelor of Science in Civil Engineering in 1989 from the Virginia Polytechnic Institute and State University. He is a registered civil engineer in Virginia, Maryland and Texas.

Mr. Scheller is currently President-elect of Washington Area Council of Engineering Laboratories (WACEL) and is involved with numerous professional organizations, including the American Society of Civil Engineers and the American Society of Testing and Materials where he is a member of Committee E36-Conformity Assessment, Committee C09-Concrete and Concrete Aggregates, and Committee D18 Soil and Rock.

Robert J. Niber, P.E.

Associate
Robert Niber, P.E., is currently an Associate with Whitlock Dalrymple Poston & Associates, P.C., and is involved primarily with the geotechnical engineering department in the firm’s Manassas, Virginia office. Mr. Niber is responsible for technical and fiscal management of geotechnical engineering, materials testing and construction inspection activities. He also participates in projects which include development and management of geotechnical investigations, construction inspection and laboratory testing programs for public sector projects as well as private sector industrial, commercial, and residential projects. Throughout his tenure at WDP, Mr. Niber’s experience has also included failure and forensic investigations with repair plans and specifications as well as expert witness/litigation support.

Prior to joining WDP in 1995, Mr. Niber was a Senior Engineer with Giles Engineering Associates, Inc., in Maryland where he was involved in the development and management of geotechnical investigations and laboratory testing programs throughout the Eastern United States. Mr. Niber’s education includes a Bachelor of Science in Civil Engineering in 1985 from the Pennsylvania State University. He is a licensed civil engineer in Virginia, Maryland, Pennsylvania, California, the District of Columbia, and West Virginia (inactive).

Mr. Niber is currently involved with several professional organizations, including the American Society for Testing and Materials Committee D-18 on Soil and Rock, the American Society of Civil Engineers, Geotechnical Section - National Capital Chapter, and the International Society of Soil Mechanics and Foundation Engineers. Mr. Niber is an active member of the Washington Area Council of Engineering Laboratories and was President of this organization in 1997.

Keith Kesner, Ph.D., P.E.

Associate
Keith Kesner, Ph.D., P.E., is an Associate with Whitlock Dalrymple Poston & Associates, P.C., and currently heads the South Norwalk, Connecticut office. Dr. Kesner participates in various structural projects, which include the evaluation of structures using nondestructive test methods, corrosion evaluations, structural analysis using both conventional and finite element methods, as well as development of technical plans and specifications for the repair and rehabilitation of structures.

Prior to joining WDP, Dr. Kesner was Project Director with the Thornton Tomasetti Group in New York where he was involved in structural analysis and the repair and rehabilitation of structures experiencing distress. Dr. Kesner was also an instructor/post-Doctoral researcher at Cornell University. He is a licensed civil engineer in Virginia, New York, California (Civil), and Connecticut. Dr. Kesner’s education includes a Ph.D. in Civil Engineering in 2003, Master of Science in Civil Engineering in 1998, both from Cornell University, and a Bachelor of Science in 1992 from The University of Connecticut.

Dr. Kesner is actively involved in several professional organizations, including the American Society of Civil Engineers, American Concrete Institute (named a Fellow in 2007), and the International Concrete Repair Institute (ICRI). Dr. Kesner received the 2005 American Concrete Institute (ACI) Young Member Award and was a co-recipient of the 1998 ACI Construction Practice Award. He is also a recipient of the 2002 ICRI Outstanding Project Award – Project of the Year, Marina del Rey Seawall Project and the 2000 ICRI Outstanding Project Award – Longevity Category 2000, Repair of the Champion International Parking Structure. Dr. Kesner serves on several ACI committees. He has authored or co-authored over 80 technical papers and presentations for industry journals and is a regular speaker at industry conferences.

Matthew J. Innocenzi, P.E

Associate
Matthew Innocenzi, P.E., is currently an Associate with Whitlock Dalrymple Poston & Associates, P.C., in the firm’s Manassas, Virginia office. He participates in many structural, material, and architectural engineering activities, specializing in nondestructive testing, evaluation, research and study of asphalt roof shingles, portland cement plaster (stucco) and the analysis, design and repair of steel members (hot-rolled and cold formed) and masonry buildings. Mr. Innocenzi performs forensic field and laboratory investigations, façade and building envelope investigations, asphalt and slate shingle roof investigations, structural inspection, analysis and design, architectural retrofit and repair, and development of design documents and repair recommendations. His experience includes building projects throughout the east coast of the United States.

Mr. Innocenzi’s education includes a Master of Engineering in Civil Engineering in 1999 and a Bachelor of Science in Civil Engineering in 1997, both from Virginia Polytechnic Institute and State University. He is a licensed civil engineer in Virginia, West Virginia, New Jersey, Maryland, South Carolina, Pennsylvania, Florida, and Tennessee.

Mr. Innocenzi is a member of the American Institute of Steel Construction and the Roof Consultants Institute, where he serves as the Educational Director of the local Mid-Atlantic Chapter. He is also a member of the American Society for Testing and Materials, where he is a committee member for ASTM Committee C11-Gypsum and Related Building Materials and Systems, and ASTM Committee D08-Roofing and Waterproofing. He has authored and co-authored various technical articles and papers for industry journals and publications relative to nondestructive testing, water testing, and stucco cladding.

Rex A. Cyphers, P.E.

Associate
Rex Cyphers, P.E., is currently an Associate with Whitlock Dalrymple Poston & Associates, P.C., and heads the Charlottesville, Virginia office. He manages many structural, material, and architectural engineering activities. Mr. Cyphers specializes in design and repair of masonry structures, historic preservation, and nondestructive testing. He performs forensic field and laboratory investigations, façade and building envelope investigations, structural inspection/analysis and design, architectural retrofit and repair, roofing and waterproofing investigations, development of design documents, and repair recommendations.

Prior to joining WDP in 2003, Mr. Cyphers was a Staff Engineer for DMJM+HARRIS, Inc., in Morgantown, West Virginia, where he contributed to various structural investigations, condition assessments, and rehabilitation projects of existing structures experiencing distress. Leading up to his experience at DMJM+HARRIS, Inc., Mr. Cyphers served in the United States Marine Corps and US Army National Guard.

Mr. Cyphers’ education includes a Master of Science in Civil Engineering in 2003 and a Bachelor of Science in Civil Engineering in 2002 both from West Virginia University. He also earned a Graduate Certificate in Cultural Resource Management in 2003 from West Virginia University. Mr. Cyphers is licensed as a civil engineer in Virginia.

Mr. Cyphers is currently a member of the Association for Preservation Technology International, the American Concrete Institute, and the American Society for Testing and Materials, where he is a member of Committee E-6-Performance of Buildings. Mr. Cyphers has presented and co-authored various technical publications.

John A.R. McIsaac, P.E., S.E., LEED AP

Senior Engineer
John McIsaac, P.E., S.E., is currently a Senior Engineer with Whitlock Dalrymple Poston & Associates, P.C., in the firm’s Manassas, Virginia office. He manages several structural, material, and architectural engineering activities. Mr. McIsaac specializes in complex structural related issues and has expertise in historic preservation and post-tensioned concrete structures. He performs forensic field and laboratory investigations, façade and building envelope investigations, structural inspection/analysis and design and waterproofing investigations, development of design documents, and repair recommendations.

Mr. McIsaac has many years of experience within the field of civil and structural engineering. Prior to joining WDP in 2007, he was a Structural Engineer for Keast & Hood Company in Washington, DC, where he managed and participated in the structural design of new buildings, including design of beams, columns, slabs, frames and footings for new multi-story concrete and steel buildings. He also generated, reviewed, and managed submissions in design development phase, construction document phase, and construction management phase. Leading up to his experience at Keast & Hood Company, Mr. McIsaac spent several years at Robert Silman Associates in Washington, DC, as a Senior Engineer. During his tenure at Robert Silman Associates, he provided structural and technical advice to architects, other engineering design consultants, contractors, and owners or owner’s representatives, as well as maintained his involvement with structural design and engineering.

Mr. McIsaac’s education includes a Master of Science in Civil Engineering in 2003 from the University of Virginia and a Bachelor of Science in Civil Engineering in 1997 from the University of Maryland. He is a member of the American Society of Civil Engineers, American Concrete Institute, American Institute of Steel Construction, and the Order of the Engineer. He is licensed as a professional engineer in Maryland, Virginia, and New Hampshire and a licensed structural engineer in Hawaii. Mr. McIsaac is also an adjunct professor at the University of Maryland and teaches courses in structural design.

Jason S. Yates, P.E.

Senior Engineer
Jason Yates, P.E., is currently a Senior Engineer for Whitlock Dalrymple Poston & Associates, P.C., in the firm's Manassas, Virginia office. His responsibilities include structural engineering analysis, field and laboratory investigative testing, compilation and analysis of field and office-generated data, construction administration, and the creation of project specifications and drawings. Mr. Yates specializes in nondestructive as well as destructive methods used for evaluating concrete and masonry structures, and is well versed in current laboratory and field testing specifications. His construction administration experience includes construction quality control field testing and inspection, client relations and project management. Mr. Yates is adept in state-of-the art procedures for data analysis, structural analysis of steel, concrete, wood, and masonry, finite element analyses, and graphical presentation of results. His experience includes numerous bridge and building projects throughout the United States.

Prior to joining WDP in 1993, Mr. Yates attended Virginia Polytechnic Institute and State University, where he received a Bachelor of Science in Civil Engineering and a Minor in History. Mr. Yates is a licensed civil engineer in Virginia and is currently a member of the International Concrete Repair Institute (ICRI). He has co-authored various technical papers on structural repairs and testing.

John M. Grill, P.E.

Senior Engineer
John Grill, P.E., is currently a Senior Engineer with Whitlock Dalrymple Poston & Associates, P.C., in the firm’s Manassas, Virginia office where he participates in and manages many structural, material, and architectural engineering activities, specializing in nondestructive testing and repair and rehabilitation of reinforced concrete structures.

Mr. Grill joined the firm in 1998, and has since participated in and conducted a wide variety of forensic field and laboratory investigations, structural condition assessments, façade and building envelope investigations, development of design documents, and repair recommendations. He has performed investigations on numerous projects utilizing surface penetrating radar, impact-echo testing, and corrosion evaluation techniques.

Mr. Grill’s education includes a Bachelor of Science in Civil and Environmental Engineering in 1997 from The University of Pittsburgh including an elective concentration in structural engineering. He is a licensed civil engineer in Virginia. Prior to joining WDP, Mr. Grill was a Construction Technician at Construction Engineering Consultants in Pittsburgh where he was responsible for performing field and laboratory tests of construction materials. Mr. Grill is currently a member of the International Concrete Repair Institute and the National Association of Corrosion Engineers.

William R. Nash, P.E.

Senior Project Manager
Bill Nash, P.E., is a Senior Project Manager with Whitlock Dalrymple Poston & Associates, P.C., in the firm's Manassas, Virginia office. Mr. Nash offers over 35 years of professional experience in the construction industry which includes field engineering, project management with both divisional and corporate responsibilities, and technical services. His management expertise in facilities and building envelope projects includes a variety of technical disciplines ranging from preconstruction building envelope coordination to construction inspections and forensic investigations. Mr. Nash also has significant experience in Heavy Civil Construction which includes projects with highway and bridges, light rail, and grade separation structures.

Prior to joining WDP, Mr. Nash had project management experience with various firms, most recently McCarthy Building Companies, Inc., and Frontier-Kemper Constructors, Inc. He comes to WDP from MC Industrial, where he was a Quality Assurance Director responsible for Delivery of Owner contractual requirements of field construction and technical assistance to construction project site staff for power, petrochemical, manufacturing, and industrial projects. While at McCarthy Building Companies, Inc., he was actively involved on the management level with construction operations, planning, and field construction activities. Further, Mr. Nash has been a leader in quality assurance by developing and implementing Divisional Strategic Initiatives at McCarthy Building Companies, Inc. for the Site Specific Quality Control Program and the Building Enclosure Coordination Program.

Mr. Nash received his Bachelor of Science in Mining Engineering as well as his Bachelor of Science in Civil Engineering, both from the University of Missouri. He is a member of numerous industry organizations, including the American Society of Civil Engineers (ASCE), American Society for Testing and Materials (ASTM), Building Envelope and Thermal Energy Council (BETEC), Construction Specifications Institute (CSI), International Concrete Repair Institute (ICRI), Roof Consultants Institute (RCI), and The Masonry Society (TMS). In addition to his industry participation on the national level, Mr. Nash is heavily involved with various national standards committees for ACI, ASCE, ASTM, and National Institute of Building Science/BETEC. He is a licensed Civil Engineer in Missouri and Louisiana.