August 1, 2017

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Stephanie Jones to Present at the National Groundwater Association's Conference

Stephanie Jones (Maryland) will present at the National Groundwater Association's conference on Groundwater Solutions: Innovating to Address Emerging Issues for Groundwater Resources in Arlington, Virginia in the Emerging Contaminants session at 4:25-4:50 p.m. on August 8, 2017.

Her presentation is entitled "Boron as an Emerging Contaminant at Coal Ash Sites and Large Plume Management Metrics." The session will focus on emerging contamination threats to groundwater resources, and the state of the art in how they can be addressed.


Boron is an emerging constituent of concern at coal combustion residual (CCR) sites because it can leach from coal ash disposal units and impact underlying groundwater. In 2015 USEPA promulgated the Federal CCR Rule, which identifies boron as an Appendix III indicator constituent for detection monitoring. Unlike other regulated constituents present at high concentrations in CCR, boron does not attenuate onto aquifer solids via sorption or precipitation of new minerals and thus it often produces large plumes in groundwater downgradient of CCR units. A recent settlement between utilities, USEPA, and NGOs indicates that boron should be added to the list of constituents in

Appendix IV of the final CCR Rule. Under the proposed change, a statistical exceedance of background concentrations for boron will trigger cleanup to background with the edge of the unit as the point of compliance. Increasingly, mass flux and mass discharge metrics are being used by groundwater practitioners to assess the impacts of CCR constituents at coal ash sites and evaluate remedial options. These metrics provide a means to quantify the mass discharge reduction needed from source control at CCR units to achieve background or risk-based screening levels across large plume areas. In combination with fate and transport modeling, the mass discharge metrics can be useful in supporting evaluation of groundwater remedies including monitored natural attenuation (MNA), in situ treatment, and source control/monitoring. They can also be used to prioritize units for closure in multi-unit systems. Stephanie's presentation will describe mass flux and mass discharge metrics and illustrate their application at CCR sites.

More Information

For more information regarding the event, visit: National Groundwater Association's conference
For more information on emerging contaminants at coal ash sites, contact Stephanie Jones at This email address is being protected from spambots. You need JavaScript enabled to view it..
To learn more about Stephanie see her profile at: