About this Project

The South Valley Parkway (SVP) was constructed to alleviate traffic congestion and improve traffic safety along SR 2008. The project consisted of a new four-lane highway with a split diamond interchange, two bridges, one culvert, and several roundabouts. AEG provided various design support for the SVP project, including geotechnical and environmental services. During construction, AEG also provided consultation services. Much of the roadway is on a new alignment and required significant excavation through the underlying bedrock. The presence of coal and black (carbonaceous) shale was a substantial consideration during design. The Llewellyn Formation is known to contain Acid-Producing Rock (APR), and exposure to the sulfide-bearing mineral pyrite represented a potential source of acidic drainage. The excavation and treatment of APR required careful consideration. Roadway design considered several mining-related features, including abandoned and reclaimed surface mines, proximity to mine shafts, and potentially unsuitable mine refuse materials.

The geotechnical aspects of the project included subsurface exploration for roadway and structure foundation design recommendations. The roadway evaluation included rock slope stability, rockfall barrier analysis, rock embankment construction, blasting, and acid-base accounting for disposal and treatment of the APR. Foundation investigation and recommendations were provided for the three structures, which included a 150-foot single-span bridge, a nearly 200-foot box culvert, and a 700-foot, six-span bridge.

In support of AEG’s geotechnical design, environmental services were conducted and included Phase II and III Environmental Site Assessments (ESA). A Health and Safety Plan/Field Sampling Plan was developed for implementing a Phase III ESA. The Phase III ESA was performed for two potential waste sites located within the project study area where the results of previous investigations completed by others identified the potential for underground storage tanks (USTs) or landfill waste materials that may be encountered during construction activities. As part of Phase III ESA activities, AEG used a photoionization detector (PID) to monitor the ambient air of on-site workers for the presence of total volatile organic vapors. In addition to PID readings, AEG used a multi-gas meter to monitor the ambient air for landfill gas parameters, including carbon monoxide, methane, and hydrogen sulfide.