| Titre | Application of the tracer radon-222 to identify groundwater discharge hotspots along the Lake Simcoe shoreline |
| Télécharger | Téléchargement (publication entière) |
| |
| Licence | Veuillez noter que la Licence du gouvernement
ouvert - Canada remplace toutes les licences antérieures. |
| Auteur | Robinson, C; Wallace, H; Ji, T |
| Source | Regional-scale groundwater geoscience in southern Ontario: an Ontario Geological Survey, Geological Survey of Canada, and Conservation Ontario open house; par Russell, H A J ; Ford, D; Priebe, E H; Commission géologique du Canada, Dossier public 8212,
2017 p. 31, https://doi.org/10.4095/299798  Accès
ouvert |
| Année | 2017 |
| Éditeur | Ressources naturelles Canada |
| Réunion | Ontario Geological Survey and Geological Survey of Canada groundwater geoscience open house; Guelph; CA; mars 1-2, 2017 |
| Document | dossier public |
| Lang. | anglais |
| DOI | https://doi.org/10.4095/299798 |
| Media | en ligne; numérique |
| Référence reliée | Cette publication est contenue dans Regional-scale groundwater geoscience in southern Ontario: an Ontario Geological Survey, Geological Survey of Canada, and Conservation Ontario open house |
| Formats | pdf |
| Province | Ontario |
| SNRC | 31D/03; 31D/04; 31D/05; 31D/06; 31D/11; 31D/12 |
| Région | Lake Simcoe |
| Lat/Long OENS | -80.0000 -79.0000 44.7500 44.0000 |
| Sujets | eau souterraine; aquifères; ressources en eau souterraine; gestion des ressources; planification; résurgence des eaux souterraines; taux de décharge; eaux de surface; lacs; littoraux; etudes isotopiques;
isotopes; radon; qualité de l'eau; substances polluantes; levés géochimiques; régimes des eaux souterraines; modèles; hydrogéologie; géochimie; géologie de l'environnement |
| Programme | Géoscience des eaux souterraines , Aquifer Assessment & support to mapping |
| Diffusé | 2017 02 22 |
| Résumé | (disponible en anglais seulement)
Groundwater discharge can be an important pathway for transporting pollutants, including nutrients, metals, and chloride into large inland lakes. Quantification
of groundwater inputs into large lakes is often challenging due to high spatial variability in discharge patterns. While prior studies have identified offshore groundwater discharge locations (submarine hollows and vents) into Lake Simcoe, there is
limited understanding of the magnitude of groundwater discharge to the lake including identification of areas that may be hotspots for discharge. The objective of this study was to evaluate the use of the natural tracer radon-222 (222Rn) for
evaluating groundwater discharge along the shoreline of Lake Simcoe. 222Rn is a suitable tracer for quantifying groundwater discharge to inland lakes as its concentrations are typically 3-4 orders of magnitude higher in groundwater than in surface
water. Regional scale 222Rn boat surveys were conducted along the shoreline of Lake Simcoe in summer 2015 and 2016 to identify potential groundwater discharge hotspots. Measurements were conducted using portable radon instrumentation (RAD 7 and RAD
AQUA, Durridge Inc.). Groundwater discharge hotspots were located along the north shore of Kempenfelt Bay and along the south shore of Lake Simcoe. Regional-scale survey results were compared with hydrogeological studies previously conducted for
subwatersheds around Lake Simcoe to gain understanding of the hydrogeological controls on the detected groundwater hotspot areas. High spatial resolution 222Rn surveys were also carried out in identified hotspot areas and a steady-state mass balance
model which considers the various sources and sinks of 222Rn (e.g., air evasion, offshore mixing) was applied to estimate groundwater discharge rates. The challenge of applying a 222Rn mass balance is minimizing uncertainties associated with 222Rn
loss through air evasion, as well as adequately characterizing 222Rn concentrations in the groundwater endmember. High resolution survey results confirmed high groundwater discharge in the hotspot areas with discharge highest near the shore and
decreasing offshore. The development of regional-scale methods such as 222Rn for evaluating groundwater discharge to large inland waters including Lake Simcoe is critical for developing effective and targeted management plans aimed reducing the
contribution of groundwater pollutants to degrading lake water quality. |
| Sommaire | (Résumé en langage clair et simple, non publié)
Procès-verbaux pour la géoscience des eaux souterraines à échelle régionale Organisée par la Commission géologique de l'Ontario, la Commission
géologique du Canada et les géoscientifiques de Conservation Ontario. La journée portes ouvertes est prévue pour 2017-03-01 et 02. L'objectif est l'engagement du public et la diffusion de la géoscience dans le sud de l'Ontario au cours de la dernière
année. |
| GEOSCAN ID | 299798 |
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