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Lake water chemistry was measured for lakes in Iceland. We used a multiparameter probe (HydroLab HL4, OTT HydroMet) to measure in situ temperature, pH, dissolved oxygen (DO), and electrical conductivity of the water column at 0.5-1 m resolution. These measurements were repeated during each field campaign, resulting in multiple years of summer water chemistry data for many lakes. For some lakes, profiles of the water column were additionally taken through the ice during a February field campaign. Additionally, 0.5-1L grab samples of surface and bottom waters were analyzed for Total Phosphorus (mg/L), Chloride (mg/L), Nitrate (mg/L), Sulfate (mg/L), TOC/DOC (mg/L), and Total Nitrogen (mg/L).
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Accurately Determining Groundwater Sulfate Concentrations from Reclaimed Landscapes with Conductometric Titrations
Conductometric titrations were used to measure sulfate concentrations in ground and surface water samples taken from land reclaimed after open-air coal mining. Sulfate concentrations ranged from 460 mg/L in surface water upstream of the former coal mine’s location to almost 3500 mg/L in groundwater sampled at the spoil site. Data from the titration measurements were benchmarked against EPA-approved ion chromatography (IC) measurements and results agreed to within ±3.6% (averaged over 36 samples) with a range of +10.4 and −11.3%. To test the generality of conductometric titration as a method for measuring dissolved constituents in environmental aquatic systems, additional measurements testing for chloride were performed with surface water samples collected from four different sites in south central and southwest Montana. Chloride concentrations ranged from 2.2 to 12 ppm. Based on measurements with control samples prepared in the laboratory, the environmental sample measurements are believed to be accurate to within ±6.4%. These conductometric titration studies highlight the technique’s simplicity, accuracy, cost effectiveness, and potential to produce rapid results. Additional analyses suggest that even simpler, non-species-specific conductivity data can provide an on-site, rapid assessment of sulfate levels in ground and surface water when historical speciation data are available.
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- Award ID(s):
- 1757351
- PAR ID:
- 10485192
- Publisher / Repository:
- ACS Publications
- Date Published:
- Journal Name:
- ACS ES&T Water
- Edition / Version:
- 1
- Volume:
- 3
- Issue:
- 8
- ISSN:
- 2690-0637
- Page Range / eLocation ID:
- 2544 to 2550
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acsestwater.3c00126
