Long‐Term Disturbance of Ground Water Chemistry Following Well Installation
- 1 November 2003
- journal article
- Published by Wiley in Groundwater
- Vol. 41 (6), 780-789
- https://doi.org/10.1111/j.1745-6584.2003.tb02419.x
Abstract
Ground water samples collected from a multilevel sampler shortly after its construction showed significantly higher alkalinity and concentrations of calcium and magnesium than those from nearby wells installed 10 years earlier. The sampler was drilled using a conventional hollow‐stem power auger in a sandy, silicate aquifer lying beneath an isthmus between two lakes in northern Wisconsin. Ground water in the study area is of low ionic strength and its chemistry is dominated by silicate mineral weathering. Periodic sampling over two years following installation of the sampler showed that the higher solute concentrations had subsequently decreased. Oxygen isotope signature and other solute species, such as sulfate and chloride, were comparable to those of older wells and did not show any notable trends over time. Independent variation of other chemical species that cannot be derived from aquifer minerals, and the similarly high concentrations in older wells shortly after their installation, suggest that rapid dissolution of fresh mineral surfaces and hyperfine particles generated during drilling has induced the enhanced concentrations. This observation is consistent with the field equivalent of laboratory mineral dissolution experiments that show initially increased dissolution rates that decay over time. Well installations for geochemical sampling in dominantly silicate material may require longer times to reach an equilibrium state than has been previously thought.This publication has 32 references indexed in Scilit:
- Plagioclase weathering in the groundwater system of a sandy, silicate aquiferHydrological Processes, 2002
- Enhanced dispersion in groundwater caused by temporal changes in recharge rate and lake levelsAdvances in Water Resources, 2000
- Model Calibration with Multiple Targets: A Case StudyGroundwater, 1999
- Chemical weathering rates of a soil chronosequence on granitic alluvium: I. Quantification of mineralogical and surface area changes and calculation of primary silicate reaction ratesGeochimica et Cosmochimica Acta, 1996
- Feldspar dissolution at 25°C and pH 3: Reaction stoichiometry and the effect of cationsGeochimica et Cosmochimica Acta, 1995
- Mechanism of plagioclase dissolution in acid solution at 25°CGeochimica et Cosmochimica Acta, 1994
- Some factors affecting the dissolution kinetics of anorthite at 25°CGeochimica et Cosmochimica Acta, 1992
- A Method for Installing Miniature Multilevel Sampling WellsGroundwater, 1991
- Geochemical mass balances and weathering rates in forested watersheds of the southern Blue RidgeAmerican Journal of Science, 1985
- Origin of the Chemical Compositions of Some Springs and LakesPublished by American Chemical Society (ACS) ,1967