Andy Vessely

Geologist and Engineering Geologist
Oregon, Washington

2000 - present
Senior Associate Geologist Cornforth Consultants

1978 - 2000
Chief Engineering Geologist Oregon Department of Transportation

1975 B.S.
University of California Los Angeles

National Academy of Science, Transportation Research Board, Committee on Engineering Geology

National Academy of Science, Transportation Research Board, Subcommittee on Rockfall Management

Member-author TRB Task Force AFP 15T publication on Rockfall Evaluation and Control

Member, Association of Engineering Geologists

Member, American Rock Mechanics Association

Member, International Society of Rock Mechanics

U.S. Representative (Debate Panel) to 11th International Congress of the International Society of Rock Mechanics; Lisbon, Portugal



Lawrence A. Pierson
Staff Consultant

Mr. Pierson has over four decades of experience in engineering geology, and is a nationally recognized expert in the field of rock mechanics with a specialty in transportation projects. Twenty-two years of his experience were with the Oregon Department of Transportation where he served as a Geotechnical Manager and Chief Engineering Geologist. He was responsible for rock slope and rockfall mitigation designs, foundation evaluations for structures, and managing quarry operations and transportation research projects. As part of national pooled-fund research projects, he has developed management and design systems including the Rockfall Hazard Rating System (RHRS) used by U.S. and Canadian transportation agencies as a rock slope management tool, and a national transportation guideline for design of rockfall catchment areas (RCAD).

With Cornforth Consultants, Inc. Mr. Pierson has managed major geotechnical projects for the Federal Highway Administration, State DOTs and regional utility companies. He has managed the development of geotechnical procedure manuals and has provided expert witness services on several rockfall litigations and construction claims for transportation agencies.

A few projects representative of Mr. Pierson’s experience include:

  • Comprehensive RHRS Implementation, Montana Department of Transportation, Montana
  • Rockfall Litigation, Washington Department of Attorney General, Washington
  • Diablo Dam Rockfall Mitigation, Seattle City Light, Washington
  • Highway 101 Neahkahnie Bridges and Viaducts Rockfall Mitigation, Manzanita, Oregon
  • Cougar Dam Intake Tower Modifications, McKenzie River, Oregon
  • Mosier Twin Tunnels, Historic Columbia River Highway, Mosier, Oregon
  • McGuire Dam Raise Quarry Excavations, Carlton, Oregon
  • ODOT Cracked Bridges, OR 212/224 and US 26, Clackamas County, Oregon
  • Rockfall Litigation, Ministry of Attorney General, British Columbia, Canada
  • Pelton Dam Access Road Widening, Madras, Oregon
  • Going-to-the-Sun Road Transportation Corridor Improvements, Glacier National Park, Montana
  • Lemolo Canal No. 2 Rockfall, Toketee Falls, Oregon
  • ODOT's Kruger Rock Stability Research Facility, Portland, Oregon
  • Warner Highway Realignment, Lake County, Oregon
  • Prospect Penstock Rockfall, PacifiCorp, Oregon
  • RHRS Implementation, Virginia and Utah Departments of Transportation
  • Al Baha Descent Highway, Ministry of Communications, Al Baha, Kingdom of Saudi Arabia
  • Third Avenue Extension, Alaska Department of Transportation and Public Facilities, Ketchikan, Alaska
  • Elim Airport Construction Claim, Alaska Department of Attorney General, Elim, Alaska