While removing the rock on SR 309 between Wilkes Barre and Mountain Top, the contractor encountered a dirt seam within the limits of the project. A dirt seam is a large cave-like area of dirt within the rock of the mountain. When the dirt seem was covered by the existing rock, it presented no problem. However, as the rock was removed and the dirt seam was exposed, the concern is that erosion will begin to cause the dirt to wash away, leaving a gap within the rock which could cause portions of the mountain to collapse.
For that reason, it is essential that the dirt seam be covered and not exposed to the elements. So this week a crew will begin to build a concrete cap that will be drilled into the rock over the dirt seam to prevent erosion of the materials. That is the reason that SR 309 is a single lane in this area and will remain so for the next few months.