thumbnail

Retardation of ammonium and potassium transport through a contaminated sand and gravel aquifer: The Role of cation exchange

ES and T Contents

By:
, , and

Links

  • The Publications Warehouse does not have links to digital versions of this publication at this time
  • Download citation as: RIS

Abstract

The role of cation exchange in the retardation of ammonium (NH4+) and potassium (K+) transport in a shallow sand and gravel aquifer was evaluated by use of observed distributions of NH4+ and K+ within a plume of sewage-contaminated groundwater, small-scale tracer injection tests, and batch sorption experiments on aquifer material. Both NH4+ and K+ were transported ???2 km in the 4-km-long contaminant plume (retardation factor, Rf = 2.0). Sediments from the NH4+-containing zone of the plume contained significant quantities of KCl-extractable NH4+ (extraction distribution coefficient, Kd,extr = 0.59-0.87 mL/g of dry sediment), and when added to uncontaminated sediments, NH4+ sorption followed a linear isotherm. Small-scale tracer tests demonstrated that NH4+ and K+ were retarded (Rf =3.5) relative to a nonreactive tracer (Br-). Sorption of dissolved NH4+ was accompanied by concomitant release of calcium (Ca2+), magnesium (Mg2+), and sodium (Na+) from aquifer sediments, suggesting involvement of cation exchange. In contrast, nitrate (NO3-) was not retarded and cleanly separated from NH4+ and K+ in the small-scale tracer tests. This study demonstrates that transport of NH4+ and K+ through a sand and gravel aquifer can be markedly affected by cation-exchange processes even at a clay content less than 0.1%.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Retardation of ammonium and potassium transport through a contaminated sand and gravel aquifer: The Role of cation exchange
Series title:
ES and T Contents
Volume
23
Issue:
11
Year Published:
1989
Language:
English
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
ES and T Contents
First page:
1402
Last page:
1408
Number of Pages:
7