At the east end of the valley, SR 24 turns northeast and crosses through a narrow pass in the hills before reaching the Black Rock Valley, which it continues across. Midway through the valley at the Silver Dollar Cafe, the highway intersects SR 241, an auxiliary route that travels south towards Sunnyside. SR 24 continues northeast from the junction and enters Benton County, where it climbs a section of the Yakima Ridge and exits the valley. The highway crosses part of the Fitzner–Eberhardt Arid Lands Ecology Reserve, a restricted wildlife preserve that forms part of the Hanford Reach National Monument. SR 24 meets SR 240, a major highway connecting to the Tri-Cities, at the northeast corner of the reserve. SR 24 turns north at the junction and travels along the northwest edge of the Hanford Site, flanked by fences on both sides of the road. The highway descends from the plateau by turning west and returning to its northerly course, eventually reaching a rest area on the south shore of the Columbia River.