Precision Structures Incorporated (PSI) specializes in swine, grain, beef and dairy agricultural buildings, with a focus on swine and grain facilities. PSI contracted with Willett, Hofmann and Associates (WHA) in 2008 to assist them in the design and permitting of the concrete manure storage pits associated with their swine facilities in Illinois and Missouri. Since the relationship began, WHA has assisted PSI with over 100 projects including nursery, farrowing, gestation and wean-to-finish facilities. The Salt River, MO facility, shown, is a 7,400-head sow complex which includes farrowing, gestation and isolation buildings.