Abstract
The radius of influence and radius of investigation of a pumping well are fundamental concepts in hydrogeology with various uses in well hydraulics and aquifer testing. However, numerous definitions have been given of these radii, which have often been equated while they are fundamentally different. Here radius of influence is qualitatively defined as the maximum distance from a pumping well up to which the influence of pumping is significant. On the other hand, radius of investigation is qualitatively defined as the maximum distance from a pumping well up to which aquifer properties have a significant influence on drawdown at the well. The exact meaning of the term significant is open to interpretation and, consequently, various operational definitions (i.e., definitions that enable quantification) have been given of radius of influence and radius of investigation. We comprehensively review these definitions and corresponding estimation methods, and discuss the relevance of each definition in view of different potential uses. We also propose new definitions that are more adapted to several applications. Next, we quantitatively compare the various definitions of radius of influence and radius of investigation. The results show that while remaining of the same order of magnitude, the radii are significantly affected by the choice of operational definition and associated parameters. As a rule of thumb, the radius of investigation is half of the radius of influence. We eventually propose a practical guide for choosing a suitable operational definition of radius of influence or radius of investigation depending on the objective.
| Original language | English (US) |
|---|---|
| Article number | 124646 |
| Journal | Journal of Hydrology |
| Volume | 583 |
| DOIs | |
| State | Published - Apr 2020 |
Bibliographical note
Funding Information:The authors acknowledge support from the Korea Research Fellowship program funded by the Korea Ministry of Science and ICT through the National Research Foundation of Korea , South Korea (grant 2016H1D3A1908042 ), the Future Research Program ( 2E29660 ) funded by the Korea Institute of Science and Technology (KIST), South Korea, and the Korea Environment Industry & Technology Institute ( KEITI ), South Korea through Subsurface Environment Management ( SEM ) Project ( 2018002440006 ) funded by the Korea Ministry of Environment (MOE). PKK also acknowledges the College of Science & Engineering at the University of Minnesota , United States and the George and Orpha Gibson Endowment for its generous support of Hydrogeology, and the Minnesota Environment and Natural Resources Trust Fund , United States as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR). The authors are grateful to two reviewers for their valuable comments. This work does not rely on any data.
Publisher Copyright:
© 2020 Elsevier B.V.
Keywords
- Aquifer test
- Pumping test
- Radius of drainage
- Radius of influence
- Radius of investigation
- Well hydraulics