The node on Grace Patterson Elementary school sits in the southwest corner of the Vallejo subnetwork, adjacent to CA 29 (to the east) and the Napa River (to the west and south). With its proximity to the water, this node serves as an excellent comparison to the eastern Vallejo subnetwork nodes, providing insight into emissions generated by traffic on busy inland roadways. In addition, it's proximity to CA 29 with limited other nearby roadways allows for clearer measurements of emissions from traffic on this freeway.