According to VDOT, the detour will remain in place for at least one day but could remain in place as long as ten days. The detour is a safety precaution and will remain until the unstable material on the slope can be brought down. The time it will take to stabilize the slope is unknown.

Crews have been blasting as part of work to repair an unstable slope near mile marker 124 on a project to construct a truck climbing lane in Montgomery County between mile markers 120 and 125.

During a scheduled blast on August 26, an existing crack in the unstable slope grew from 50 feet to 120 feet in length.

Geotechnical specialists have spent the day reviewing the slope, and VDOT decided to close the southbound lanes of the Interstate in the interest of public safety.

The next blast is scheduled for August 28 at 9 a.m. Once this blast is complete, a more definite time frame for how long the detour will be in place will be made available.

During the blast on August 28, State Police will slow traffic on northbound I-81 beginning at mile marker 114. Once the blast is over, traffic will return to a normal speed. Drivers should expect delays. During blasting, the on-ramps will be restricted onto northbound Interstate 81 at exit 118 (Christiansburg). Flaggers will control traffic on Route 636 ( Seneca Hollows Road and Friendship Road) during blasting