Environmental Engineering Reference
In-Depth Information
Fig. 1
Location of Hathershage in the
United Kingdom
Sheffield
Hathersage
potential for location of point sources of PGE higher up in the drainage catchment
for Hathersage which is small and occupied by moor land (Figs.
1
and
2
). Therefore
this study identifies the distribution of PGE derived predominantly from catalytic
converters in this small town with a population of nearly 2,000 inhabitants (1,867
people)
[15]
. In addition, the analyses of samples for gold (Au) allows a compari-
son of the distribution of Au with Pt, Pd and Rh and analyses of osmium (Os),
iridium (Ir) and ruthenium (Ru) provide a complete record of the PGE content in
these samples. Any values above 2 ppb for the PGE are above background values
of natural abundances, which are extremely low away from the major geological
sources of PGE in South Africa and northern Siberia
[16]
.
Sampling and Methods
Eleven sites on roads (A-K) were chosen for collection of paired road dust
and gully waste samples. Sites A, B, C, D and E are on low traffic roads in residen-
tial areas up slope of the main road. Sites F and I are located on the main road
with F in the centre of Hathersage (by the George Hotel) and I on the eastern
edge of Hathersage. Site J is outside the school and north east of the main road
and sites G, H and K are on minor roads down slope and to the south of the
main road (Fig.
2
).
Samples were collected in summer and winter with a set of road dust samples
collected on 12 December 2005 in dry conditions, and paired sets of road dust and
gulley samples collected on 11 and 12 July 2006 respectively, also in dry conditions
and again in the winter on 11 December 2006 in rainy conditions (Table
1
). Traffic
flow per hour during the day, not during rush hour periods, was counted at all sites
in winter 2006 and summer 2006 and averaged values for each site are given in
Table
1
. Four samples of stream sediment were collected from the main small
stream that drains Hathersage, one upstream and two just downstream of the main
road and one 150 m further downstream. Additionally one sample was collected
from the much larger (approximately 15 m wide) River Noe (Figs.
1
and
2
).
The samples were dried and sieved to less than 1 mm, crushed and analyzed
for all six PGE and Au using Ni sulphide fire assay and an ICP-MS finish.
