HAZARDOUS MATERIALS IN THE DESIGN AND CONSTRUCTION OF TRANSPORTATION FACILITIES

The North Carolina Department of Transportation’s mission is to connect people and places in North Carolina - safely and efficiently, with accountability and environmental sensitivity. In the process of fulfilling our mission we often encounter contaminated and hazardous materials on a wide variety of projects including highway widening, ferry operations, railroad sidings, bus stations, airport expansions, and bicycle and pedestrian trails. The GeoEnvironmental Section of the Department’s Geotechnical Engineering Unit is tasked with investigating known and potentially contaminated properties to assist in the planning, design, construction, and maintenance of transportation projects to ensure that all waste management is safe, legally sound, cost effective, and environmentally sustainable.

The GeoEnvironmental Section uses various information-gathering tools to locate and characterize subsurface objects that may present a hazard to site workers and/or the traveling public. These tools are common throughout the industry and include informal interviews with local citizens, the records review of known incidents, geophysical surveys, and soil and ground water sampling. The Department is often in an uncommon position of not being responsible for the contamination, which allows for alternative methods to address these sites of concern. One such method is to minimize the impact of the transportation project on the site by design revisions. Several projects have been successfully completed by either avoiding the contamination or by making the worksite safe for the workers and the traveling public while leaving a majority of the contaminated material in place and undisturbed until which time the regulators and responsible party can address the site.

A brief overview of the life cycle of transportation projects will be presented to illustrate our involvement in the project development, planning, design, right of way, construction, and maintenance of a typical transportation project. A road widening project in Boone, North Carolina will provide a case study in which an unusually high number of known and potentially contaminated sites were addressed prior to and during construction.