Three-dimensional hydraulic tomography analysis of long-term municipal
wellfield operations: Validation with synthetic flow and solute
transport data
Abstract
This study proposes the utilization of municipal well records as an
alternative dataset for large-scale heterogeneity characterization of
hydraulic conductivity () and specific storage () using hydraulic
tomography (HT). To investigate the performance of HT and the
feasibility of utilizing municipal well records, a three-dimensional
aquifer/aquitard system is constructed and synthetic groundwater flow
and solute transport experiments are conducted to generate data for
inverse modeling and validation of results. In particular, we
simultaneously calibrate four groundwater models with varying
parameterization complexity using five datasets consisting of different
time durations and periods. Calibration and validation results are
qualitatively and quantitatively assessed to evaluate the performance of
investigated models. The estimated and tomograms from different model
cases are also validated through the simulation of independently
conducted pumping tests and conservative solute transport. Our study
reveals that: 1) the HT analysis of municipal well records is feasible
and yields reliable heterogeneous and distributions where drawdown
records are available; 2) accurate geological information is of critical
importance when data density is low and should be incorporated for
geostatistical inversions; 3) the estimated and tomograms from the
geostatistical model with geological information are capable in
providing robust predictions of both groundwater flow and solute
transport. Overall, this synthetic study provides a general framework
for large-scale heterogeneity characterization using HT through the
interpretation of municipal well records, and provides guidance for
applying this concept to field problems.