Influence of groundwater composition on subsurface iron and arsenic removal.
Subsurface arsenic and iron removal (SAR/SIR) is a novel technology to remove arsenic, iron and other groundwater components by using the subsoil. This research project investigated the influence of the groundwater composition on subsurface treatment. In anoxic sand column experiments, with synthetic groundwater and virgin sand, it was found that several dissolved substances in groundwater compete for adsorption sites with arsenic and iron. The presence of 0.01 mmol L(-1) phosphate, 0.2 mmol L(-1) silicate, and 1 mmol L(-1) nitrate greatly reduced the efficiency of SAR, illustrating the vulnerability of this technology in diverse geochemical settings. SIR was not as sensitive to other inorganic groundwater compounds, though iron retardation was limited by 1.2 mmol L(-1) calcium and 0.06 mmol L(-1) manganese.
Delft University of Technology, Stevinweg 1, 2628 CN Delft, The Netherlands. D.H.Moed@tudelft.nl
D H
DH
Moed
D
D
van Halem
J Q J C
JQ
Verberk
G L
GL
Amy
J C
JC
van Dijk
D001151:Arsenic / Q000737:chemistry*; D002118:Calcium / Q000737:chemistry; D060587:Groundwater / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D008345:Manganese / Q000737:chemistry; D009566:Nitrates / Q000737:chemistry; D010710:Phosphates / Q000737:chemistry; D017640:Silicates / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D009566:Nitrates; D010710:Phosphates; D017640:Silicates; D014874:Water Pollutants, Chemical; D008345:Manganese; D007501:Iron; D001151:Arsenic; D002118:Calcium