The impact of urban groundwater upon surface water - eTheses ...

WATER QUALITY INTERACTIONS
aluminium are associated with a single plume in which the aluminium is mobile as a complex
with fluoride.
The shallow piezometers show a similar pattern to the riverbed piezometers with additional
failures for Pb and Cd. Many of the failures for lead were situated in residential areas adjacent
to busy roads and the source of the lead may be associated with the combustion of leaded fuel.
The lower concentrations of lead in the riverbed piezometers implies restricted mobility for
the lead (perhaps due sorption) or dilution.
The abstraction wells have EQS failures for SO4, Fe, Cr, Zn, TCM, PCE, TCE and additional
failures against the DWS of NO3, K, Mn, As, Ni, DCE and VC. The most widespread
contamination is by NO3 and TCE which would be significant if the abstraction wells were
ever to be used for drinking-water supply.
7.10 Concluding Discussion
The urban groundwater quality data from the Tame Valley showed evidence of widespread
anthropogenic contamination by the presence of industrial volatile organic compounds
(primarily chlorinated solvents), heavy metals, and high concentrations of calcium, sodium,
aluminium, fluoride, chloride, sulphate and nitrate. The survey did not analyse for other
organics such as pesticides, semivolatiles and non-volatiles. The urban data showed
considerably higher levels of electrical conductivity, major cations and anions than the natural
background data set from Sutton Park and the deep borehole beneath Birmingham city centre.
However, it was recognised that Sutton Park lies at the head of the catchment and is
representative of a local, relatively rapid, groundwater flow system (as evidenced by the
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