Rhonda, According to Frank Thompson," A History of Calamine" (Sharp County Journal publication Jan 1982 -Calamine, Arkansas) The Union Camp (Ferguson) was a Regimental Encampment located "three miles south of Calamine Near the Milligan Campground."
Calimine should appear on most maps.
As for the Pete Wasson Road/Camp near New Hope Church, it is most easily located off AR Highway 115 a few miles east of Smithville. It connects AR Hwy 115 to the highway that runs from Powhatan to Lynn, Arkansas. I hope this will help you know the general area. The camp was located to the west of the present day road (Smithville side) and as the locals say "as the crow flies" the Camp is just ashort distance outside Smithville.