The Branstetter Mill Site, which operated continuously from the early 1950s until 1976, is located within the City of Redding in a once rural agricultural area currently undergoing increased residential development. In 2006, VESTRA was retained by the property owner to conduct a site investigation in part to determine whether a pentachlorophenol (PCP) dip tank once used to treat fresh-cut pine against blue sap staining impacted soils around the former mill site.

Elements of this site investigation included a detailed reconstruction of the mill layout based on historical aerial photographs, US Geological Survey topographic maps, existing site structures, and interviews with past mill employees. As part of the site field investigation, more than 20 test pits were excavated throughout the site. Soil samples were collected from each test pit and analyzed for relevant constituents of concern. The location of the dip tank was determined based on visual markers remaining on site in combination with aerial photographs. Soils surrounding the former dip tank tested positive for PCP, resulting in a phased overexcavation of the dip tank area that resulted in the excavation and removal of more than 400 tons of soil.