Lava Hot Springs is in the southeast corner of this area, which consists of valleys that are mostly private and mountains that are mostly public. It produces some big elk to hunters who draw rifle tags. Elk and mule deer bowhunters may buy tags over the counter.

This area, like many in southeastern Idaho, occasionally produces a once-in-a-lifetime mule deer that is large enough to qualify for listing in Boone and Crockett Club records, but hunting pressure is heavy enough that most bucks are shot during their first two seasons of carrying antlers. A limit on bull elk tags can let some animals grow to trophy size. Bowhunters may buy elk tags over-the-counter, but rifle bull hunters must draw tags.

This area stretches from Pocatello west to the Portneuf Valley and from Lava Hot Springs on the southern end to about 10 miles inside the Fort Hall Indian Reservation in the north. The Portneuf Range is the largest mountain range in the unit and is east and northeast of Inkom and McCammon. The north end of the range extends into the Fort Hall Indian Reservation. The less-imposing Pocatello Range lies between Pocatello and the Portneuf Range. Broad, grassy valleys are on the west and east sides of the ranges and are generally flat and contain streams, such as the Portneuf River, which runs through Portneuf Valley in the east and through Marsh Valley in the west.

Grasses and sagebrush cover up most of the valleys with willows and other brush growing along streams. Much of the valley floor near Chesterfield is composed of farm fields and includes square and round, center-private-irrigated alfalfa crop land. Foothills are mostly sagebrush covered with patches of junipers and aspens. The mountains are mostly open, grassy and sagebrush-covered slopes on western exposures and conifers on eastern exposures with large aspen woods in mountain valleys.

Most of the Portneuf Range is in the Caribou National Forest, but access is limited by private land that borders the forest. Some roads that lead into the forest are the Wood River Road north of Pebble, the Pebble Creek Road west of Pebble, the Toponce Creek road southeast of Chesterfield Reservoir, and the Inman Canyon Road that leads to the Inman Canyon trailhead northeast of Inkom. County and BLM officials have succeeded in stopping some ranchers from blocking access on roads that cross private land, but some roads have been closed.

Pebble Guard Station is at the base of Bonneville Peak along Pebble Creek. Hunters can reserve a one-room cabin on four fenced acres. It can be reached in winter with a snowmobile. The old Ranger Station has a mudroom/porch with a large sink with countertop and shower facilities. The main room serves as the kitchen and sleeping room. Corrals are available for stock. There is parking space available for four RVs. Big Springs Campground is along Pebble Creek. The turnoff is on Old Highway 30 about nine miles north of Lava Hot Springs.