INTERA’s Robert “Rob” Sengebush recently co-authored an article on the history and groundwater quality of an alluvial aquifer in the lower San Diego River Valley. Published in the November 2015 edition of Environmental & Engineering Geoscience, the article presents a hypothesis describing the Quaternary history of the Valley based on similar histories elsewhere along the southern Californian coastline and evidence from borehole logs and cores collected in the valley. The hypothesized history is then used to explain the occurrence of brackish groundwater quality in the Quaternary-age alluvial deposits and the deeper, Eocene-age sedimentary rocks beneath the Valley. The purpose of the article is to identify the background groundwater quality in the Valley in order to bring closure to the remediation of a large fuel release from the Mission Valley Terminal. Once demonstrated that the remediation efforts have restored background groundwater quality conditions, the City of San Diego’s goal is to re-develop this groundwater resource.