Modeling the geologic architecture of an aquifer and visualizing its three-dimensional structure require lithologic data recorded during well drilling. Uncertainties in layer boundaries arise due to questionable quality of drilling records, mixing during the drilling process, which results in blurred contacts, and natural heterogeneity of the geologic materials. An approach for modeling and vis...

Groundwater is the only source of water for domestic as well as agricultural purposes in the sand aquifer in between sea and lagoon configuration typically found in the eastern Sri Lanka. This study was carried out to estimate the safe yield and assess the vulnerability of the sandy aquifer on the eastern coastal belt of Sri Lanka by rapid urbanization, agriculture and as well as climate change...

The Pearl River Delta (PRD), located in the coastal area of South China, contains a large confined Quaternary aquifer. This aquifer has been identified to have high concentrations of total dissolved solids–ranging from 1 g/l in the inland area to 26.8 g/l near the southeast shoreline. This work aims to investigate the origin of groundwater salinity and the major hydrogeochemical processes contr...

This uniquely designed study investigates a fundamental issue—the feasibility of predicting stream depletion rates using linear uniform two-dimensional models. Required input for these models includes the hydraulic parameter estimates of the aquifer and the stream–aquifer interface, which may be obtainable through pumping test data analysis. This study utilizes pumping test data collected near ...

[1] The method of recession analysis proposed by Brutsaert and Nieber (1977) remains one of the few analytical tools for estimating aquifer hydraulic parameters at the field scale and beyond. In the method, the recession hydrograph is examined as dQ/dt = f(Q), where Q is aquifer discharge and f is an arbitrary function. The observed function f is parameterized through analytical solutions to th...

A polyphasic approach based on cultivation and direct recovery of 16S rRNA gene sequences was utilized for microbial characterization of an aquifer contaminated with chlorinated ethenes. This work was conducted in order to support the evaluation of natural attenuation of chlorinated ethenes in groundwater at Area 6 at Dover Air Force Base (Dover, DE). Results from these studies demonstrated the...

Transport behaviors of unidentified flagellated protozoa (flagellates) and flagellate-sized carboxylated microspheres in sandy, organically contaminated aquifer sediments were investigated in a small-scale (1 to 4-m travel distance) natural-gradient tracer test on Cape Cod and in flow-through columns packed with sieved (0.5-to 1.0-mm grain size) aquifer sediments. The minute (average in situ ce...

Gisser and Sánchez (1980a) state the conditions under which welfare gains from policy intervention are negligible in aquifer management, when compared with non-regulation or “free market” outcomes. This is the so-called Gisser-Sánchez effect (GSE), which has been supported by the ensuing literature during recent decades. The GSE requires a number of assumptions, among which is the disregard for...

Head measurements at a single observation well during a cross-hole pumping test carry a great amount of information about aquifer heterogeneity other than the average property of the aquifer as implied in Theis analysis of aquifer test. In this commentary, we use simple examples and a probabilistic reasoning approach based on Darcy’s law to unravel this information, buried in the results of qua...

Introduction Guarani Aquifer System (SAG) is the formal denomination for a transboundary aquifer underlying four countries (Argentina, Brazil, Paraguay and Uruguay) in South America. Due to its strategic importance, a joint research project aiming for sustainable management and preservation of the aquifer was initiated by the four neighbour countries together. In this work, an overview of hydro...