White Pass reopened after being closed for more than seven hours Monday.
A rock slide near the Oak Creek feeding station blocked the road about 9:30 a.m.
The slide hit a truck and the driver suffered a hand injury, according to Yakima Valley Office of Emergency Management.
Engineering staff assessed the hillside and are continuing to monitor the slope, according to the state Department of Transportation. Maintenance crews cleared the roadway and reopened the road at 5 p.m.
Several large rocks, about three feet in size, as well as smaller rocks and debris fell onto the road.
The closure was near the junction of highways 12 and 410 outside of Naches.