O'Brien County Engineers, Primghar, Iowa No description specified. 1-2 (2 Records) Documents Results of a Phase 1 Cultural Resources Inventory at a Proposed Bridge Replacement Project (N-27) IN O'Brien County, Iowa. (2002) Results of a Phase 1 Cultural Resources Inventory at a Proposed Bridge Replacement Project (P-7) IN O'Brien County, Iowa. (2002)