title: Non-invasive flow path characterization in a mining-impacted wetland.
abstract: Time-lapse electrical resistivity (ER) was used to capture the dilution of a seasonal pulse of acid mine drainage (AMD) contamination in the subsurface of a wetland downgradient of the abandoned Pennsylvania mine workings in central Colorado. Data were collected monthly from mid-July to late October of 2013, with an additional dataset collected in June of 2014. Inversion of the ER data shows the development through time of multiple resistive anomalies in the subsurface, which corroborating data suggest are driven by changes in total dissolved solids (TDS) localized in preferential flow pathways. Sensitivity analyses on a synthetic model of the site suggest that the anomalies would need to be at least several meters in diameter to be adequately resolved by the inversions. The existence of preferential flow paths would have a critical impact on the extent of attenuation mechanisms at the site, and their further characterization could be used to parameterize reactive transport models in developing quantitative predictions of remediation strategies.
authors.affiliation: Hydrologic Science and Engineering Program, Colorado School of Mines, 1500 Illinois St., Golden, CO 80401, United States. Electronic address: james.c.bethune@gmail.com.
authors.forename: James
authors.initials: J
authors.lastname: Bethune
authors.affiliation: Hydrologic Science and Engineering Program, Colorado School of Mines, 1500 Illinois St., Golden, CO 80401, United States.
authors.forename: Jackie
authors.initials: J
authors.lastname: Randell
authors.affiliation: U.S. Geological Survey, 3215 Marine Street, Suite E-127, Boulder, CO 80303, United States.
authors.forename: Robert L
authors.initials: RL
authors.lastname: Runkel
authors.affiliation: Hydrologic Science and Engineering Program, Colorado School of Mines, 1500 Illinois St., Golden, CO 80401, United States.
authors.forename: Kamini
authors.initials: K
authors.lastname: Singha
mesh_terms: D003120:Colorado; D004784:Environmental Monitoring / Q000379:methods*; D062070:Hydrology / Q000379:methods*; D008906:Mining; D008962:Models, Theoretical; D012621:Seasons; D014874:Water Pollutants, Chemical / Q000032:analysis; D053833:Wetlands
chemical_list: D014874:Water Pollutants, Chemical
keywords: Acid mine drainage; electrical resistivity; wetland