{"accessLevel": "public", "bureauCode": ["020:00"], "contactPoint": {"fn": "Michael Brooks", "hasEmail": "mailto:brooks.michael@epa.gov"}, "description": "Source strength functions (SSF), defined as contaminant mass discharge or flux-averaged concentration from dense nonaqueous phase liquid (DNAPL) source zones as a function of time, provide a quantitative model of DNAPL source-zone behavior.  Such information is useful for making site management decisions.  We investigate the use of historic data collected during long-term monitoring (LTM) activities at a site in Rhode Island to predict the SSF based on temporal mass discharge measurements at a fixed location, as well as SSF estimation using mass discharge measurements at a fixed time from three spatially distributed control planes.  Mass discharge based on LTM data decreased from ~300 g/day in 1996 to ~70 g/day in 2012 at a control plane downgradient of the suspected DNAPL source zone, and indicates an overall decline of ~80% in 16 years.  These measurements were compared to current mass discharge measurements across three spatially distributed control planes.  Results indicate that mass discharge increased in the downgradient direction, and was ~6 g/day, ~37 g/day, and ~400 g/day at near, intermediate, and far distances from the suspected source zone, respectively.  This behavior was expected given the decreasing trend observed in the LTM data at a fixed location.  These two data sets were compared using travel time as a means to plot the data sets on a common axis.  The similarity between the two data sets gives greater confidence to the use of this combined data set for site-specific SSF estimation relative to either the sole use of LTM or spatially distributed data sets. \n\nThis dataset is associated with the following publication:\nBrooks, M.C., A.L. Wood, J. Cho, C.A.P. Williams, B. Brandon, and M.D. Annable. Source strength functions from long-term monitoring data and spatially distributed mass discharge measurements.   JOURNAL OF CONTAMINANT HYDROLOGY. Elsevier Science Ltd, New York, NY, USA, 219: 28-39, (2018).", "distribution": [{"downloadURL": "https://pasteur.epa.gov/uploads/10.23719/1432673/SDMF-Brooks-20180330.xlsx", "mediaType": "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet", "title": "SDMF-Brooks-20180330.xlsx"}], "identifier": "https://doi.org/10.23719/1432673", "keyword": ["long-term monitoring data", "mass discharge", "mass flux", "passive flux meters", "source strength function", "source zone characterization"], "license": "https://pasteur.epa.gov/license/sciencehub-license.html", "modified": "2018-04-11", "programCode": ["020:097"], "publisher": {"name": "U.S. EPA Office of Research and Development (ORD)", "subOrganizationOf": {"name": "U.S. Environmental Protection Agency", "subOrganizationOf": {"name": "U.S. Government"}}}, "references": ["https://doi.org/10.1016/j.jconhyd.2018.09.003"], "rights": null, "title": "Source Strength Functions from Long-Term Monitoring Data and Spatially Distributed Mass Discharge Measurements"}