Field and modelling studies to assess the risk to UK groundwater from earth-based stores for livestock manure
Gooddy, D.C.; Hughes, A.G.; Williams, A.T.; Armstrong, A.C.; Nicholson, R.J.; Williams, J.R.. 2001 Field and modelling studies to assess the risk to UK groundwater from earth-based stores for livestock manure. Soil use and managment, 17 (2). 128-137. 10.1111/j.1475-2743.2001.tb00018.xBefore downloading, please read NORA policies.
Boreholes have been constructed at eight sites on the Permo-Triassic Sandstone and Chalk aquifers to assess the extent of chemical and microbiological contamination emanating from unlined farm manure stores. Slurry along fracture faces in the Chalk was found on cores taken from beneath two stores. Porewaters from the Chalk sites and one of the Sandstone sites were discoloured and showed high concentrations of nitrate, ammonium and organic carbon to depths in excess of 10 m. Although Cryptosporidia and Escherichia coli O157 were found in many of the cattle slurry lagoons, neither were found in the aquifer material beneath. The self-sealing of unlined slurry stores is seen as a crucial step in minimizing leakage. A simple mass balance shows farm boreholes near to contaminant sources are at greater risk than public supply wells. Contaminant modelling shows discontinuing use of an unlined farm manure store will lend to little difference in solute concentrations over the short to medium term. Groundwater is most at risk where the water table is shallow since direct hydraulic connection between the lagoon base and the water table considerably increases the rate of vertical migration. This is of greatest significance for pathogens that are thought to be relatively short lived in the subsurface. Under the majority of situations minimal threat is posed to potable groundwater drinking supplies.
|Programmes:||BGS Programmes > Groundwater Management|
|Additional Keywords:||GroundwaterBGS, Groundwater, Point source pollution, Groundwater modelling|
|NORA Subject Terms:||Agriculture and Soil Science
|Date made live:||24 Jul 2009 10:15|
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