Prepared an alternative source demonstration report for groundwater constituent exceedances per federal CCR Rule requirements.
Completed supplemental investigation work including a high-resolution transducer data collection study, rotosonic drilling monitoring well installation, coal mine seep reconnaissance, and production well surveying.
Devised a "multiple lines of evidence" demonstration concluding that groundwater impacts consisting of low pH, high sulfate, high TDS, high iron, and high cobalt were related to a historically mined area located upgradient of the regulated CCR units.
Reinterpreted groundwater flow directions at the site by integrating surface water and groundwater interactions.
Updated the conceptual site model through consideration of Army Corps of Engineers dam structure located in close proximity to the site.
Used statistical methods to define background geochemical variability.
Conducted a correlation analysis to identify indicator parameters associated with mining activities.
Created Piper and Stiff diagrams to characterize groundwater geochemical fingerprints associated with different zones.