GEOSCAN, résultats de la recherche


TitreHydrogeochemical investigations of the Crysler-Finch esker system, South Nation River watershed, eastern Ontario
AuteurAlpay, S
Source 2008, 14 pages
Séries alt.Secteur des sciences de la Terre, Contribution externe 20080400
ÉditeurSouth Nation Conservation Authority
Lat/Long OENS-75.5000 -75.0000 45.5000 45.2500
Sujetsbassins versants; elements glaciaires; topographie glaciaire; eau souterraine; géochimie des eaux souterraines; hydrogéologie
Illustrationsplots; location maps
ProgrammeProgramme de cartographie des eaux souterraines
Résumé(Sommaire disponible en anglais seulement)
The hydrogeochemical reconnaissance study of the Crysler-Finch esker system aimed to characterize groundwater geochemistry and understand groundwater interactions between the esker systems and regional groundwater flow. Residential wells were sampled within a spatial transect along an inferred groundwater flow line. Many wells were completed in bedrock and drew water from the contact zone aquifer at the interface between basal sediments and the fractured bedrock. The study also included samples from wells outside the transect area with stratigraphic control on the screened well interval and drilled piezometers from which geochemical signatures could be identified for specific hydrostratigraphic units.
Groundwater samples from piezometers drilled in this study were affected by drilling artifacts. Field measurements (pH, conductivity, and temperature) and laboratory analyses (boron (B), aluminum (Al), and manganese (Mn)) demonstrated residual effects of drilling mud on water chemistry. These effects were mitigated through well development techniques such as bailing, surging, pumping and injecting compressed air into the piezometers. Some of the drilling fluid artifacts appeared to have persisted (e.g., Concession 6/7), despite development procedures which yielded clear discharge water and stabilized field pH, conductivity and temperature measurements. Piezometers will be re-sampled after further development to assess changes in groundwater chemistry. Persistence of drilling fluid artifacts has implications for groundwater quality and studies in recently drilled piezometers.