『Abstract
The cutting operations of dimension stone at quarries produce
a large amount of fines that, in turn, cause a negative environmental
impact over local surface waters. This article presents a detailed
analysis of the mobilized contamination associated with runoff
waters in a large granite quarry (〜200 ha) which is located in
Porrino（nの頭に〜） (Galicia, NW Spain), the most
important production centre of dimension stone in Spain. There,
an intensive monitoring survey was developed in order to characterize
the hydrology of the system as well as the release and transport
of pollutants. This was accomplished by means of different control
sections for the flow and by the collection of 52 random water
samples. Automatic samplers were also used to collect 192 water
samples associated with runoff generated by significant rain events.
For each of the samples collected, a wide battery of analytic
determinations was performed, including solid loads, turbidity,
organic pollution, nutrient and selected metals. Upon careful
examination it has been possible to obtain different parameters
related to the contamination control, like the “event mean concentration”(EMC),
maximum concentrations and specific sediment loads. Moreover,
a comprehensive statistical study including parameter correlation
and cumulative probability analyses helped to understand the pollutant
mobilization behaviour within the quarry system. It can be concluded
that mobilized contamination shows the anomalous presence of some
metals, whose concentrations are in excess when compared to the
natural rock. This excess metal amount must be attributed to an
anthropogenic source associated to mining and cutting operations.
Keywords: Granite quarries; Runoff water pollution; Suspended
solids; Selected metals; Statistical analysis; Spain; Galicia;
Porrino（nの頭に〜）』
Introduction
Materials and methods
Methods
Control program
Results
Hydrological characterization
Characterization of pollution
Ransom samples
Samples associated with rainfall events
Discussion
Accumulated probability curves of all random sample values
Accumulated probability curves of the event samples in control
stations 3, 4 and 5
Accumulated probability curves of selected metals in control
stations 3-5
Correlations
Analysis of the anomalous presence of some selected metals
Conclusions
References