Corridor H, Sections 3 & 5

Section 3: The original design of Corridor H Section 3 had a bifurcated median; TERRADON changed the median width to match that of the adjoining sections, providing a consistent typical median width for the project. In addition, horizontal alignment and vertical alignment were adjusted to improve earthwork balance with cost savings of approximately $300,000 obtained by revising the alignments. Active coal mining operations were being performed after the contractor began road building  activities. As a result, the existing ground changed significantly  between the original construction plans and the actual conditions. The Value Engineered plans used the revised ground surface to create more accurate plans and earthwork volumes. The existing ground had been changed by as much as 70’ in elevation; therefore, side road alignments were adjusted to match the revised horizontal and vertical alignments.

Section 5: Vertical alignment was modified to improve the earthwork balance, and cost savings of approximately $700,000 were obtained by revising the alignments. Existing utility crossings and impacts had to be addressed in the re-design, and side road alignments were adjusted to match the revised vertical alignments. Changes to the profile resulted in revised drainage areas and culvert designs, further improving the cost of the alignment. Acid bearing material was encountered in the project limits. The original alignment was below the acid bearing material, but the raised profile placed a significant portion of the alignment above the acid bearing material, which resulted in a more environmentally friendly project.