Hydrological parameter estimations from a conservative tracer test with variable-density effects at the Boise Hydrogeophysical Research Site: HYDROLOGICAL PARAMETER ESTIMATIONS

Journal Article · Thu Dec 01 04:00:00 EST 2011 · Water Resources Research

DOI:https://doi.org/10.1029/2011WR010789· OSTI ID:1364017

Dafflon, B.; Barrash, W.; Cardiff, M.; Johnson, T. C.

Reliable predictions of groundwater flow and solute transport require estimation of the detailed distribution of the parameters controlling these processes. However, such parameters are difficult to estimate due to the inaccessibility of the subsurface and the complexity of the processes. In this regard developments in parameter estimation techniques and investigations of field experiments are still challenging and necessary to improve our understanding of hydrological processes, and of how to best simulate them. Here we present the analysis of a conservative tracer test conducted at the Boise Hydrogeophysical Research Site in 2001 in a heterogeneous unconfined fluvial aquifer. Some relevant characteristics of this test include: variable-density (sinking) effects due to the injection concentration of the bromide tracer, relatively small size of the experiment, and availability of various sources of geophysical and hydrological information at the site. The information contained in this experiment is investigated through several parameter estimation approaches, including a grid-search-based strategy, stochastic simulation of hydrological property distributions and deterministic inversion using regularization and multi-point techniques. Doing this allows us to estimate hydrological property distributions and also compare several methods and parameterizations. Results provide new insights into the understanding of variable-density transport processes and the hydrological relevance of incorporating various sources of information in parameter estimation approaches. Amongst others, the variable-density effect and the porosity distribution, as well as their coupling with the hydraulic conductivity structure, are seen to be significant in the transport process. Results also show that assumed prior information can strongly influence the estimated hydrological property distributions.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1364017
• Report Number(s): PNNL-SA--79976; KP1702030
• Journal Information: Water Resources Research, Journal Name: Water Resources Research Journal Issue: 12 Vol. 47; ISSN 0043-1397
• Publisher: American Geophysical Union (AGU)
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
flow
geophysics
radar
tracer
transport