Dataset Information

Source strength functions from long-term monitoring data and spatially distributed mass discharge measurements.

ABSTRACT: 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 calibration of screening-level models to assist with 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.

SUBMITTER: Brooks MC

PROVIDER: S-EPMC7390023 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Source strength functions from long-term monitoring data and spatially distributed mass discharge measurements.

Brooks Michael C MC Wood A Lynn AL Cho Jaehyun J Williams Christine A P CAP Brandon William W Annable Michael D MD

Journal of contaminant hydrology 20180921

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 calibration of screening-level models to assist with 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 ...[more]

PMID: 30361116

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Dataset Information

Source strength functions from long-term monitoring data and spatially distributed mass discharge measurements.

Publications

Source strength functions from long-term monitoring data and spatially distributed mass discharge measurements.

Similar Datasets

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