* At the time this paper was submitted for publication monitoring data was available only through month 18. The results from the month 18 sampling event indicated the presence of small but detectable amounts of Perfluorooctanesulfonate (PFOS) and Perfluoroundecanoic acid. Both detections were well below the US EPA Health Advisory Level. Further groundwater sampling and analyses performed at this site have indicated that all PFAS compounds analyzed for, including these two specific compounds, are below detection level.