Environmental Engineering Reference
In-Depth Information
Total Concentrations of Major and Trace Elements
Runoff elemental concentrations, named “total concentrations”, include the bulk
concentrations that desorbed from dispersed particulate matter exposed to nitric
acid (surface-bound constituents) as well as a part of particles themselves which are
dissolved by acidification process, plus the constituents present initially as dis-
solved species.
Al, Fe and Mn concentrations varied widely between rain events, but no rela-
tionship could be established between these elements and SS, probably due to the
incomplete dissolution of minerals and to the contribution of organic matter. High
variations of total trace elements concentrations were measured over the data col-
lection period (Table
2
). A comparison with the literature showed that the concen-
trations of heavy metals were in the same range as measured 10 years ago at the
Cheviré site
[14]
. Values were also in the same range as current measurements in
England
[5]
.
Despite the removal of lead from fuel, the constant concentration of Pb could be
attributed to the increase of traffic and to the presence of other sources of lead than
leaded gasoline. Ca and Na were the main major elements in runoff waters, as
generally observed for surface waters. The quite high concentration of K could
Table 2
Results of the water analysis. Total concentrations of trace elements
Event date
Zn
Cd
Cr
Cu
Ni
Pb
µg/L
Aug 24, 2004
275
0.08
0.9
47
3.0
2.0
Sept 10, 2004
1,618
0.21
6.5
49
7.8
25.9
Nov 10, 2004
1,900
0.39
5.2
24
9.0
28.3
Oct 10, 2004
1,837
0.90
14.9
169
10.1
68.7
Apr 10, 2004
2,744
0.38
17.5
186
15.1
50.8
Apr 10, 2004
2,052
0.20
7.1
153
8.3
15.4
Nov 26, 2004
815
0.44
14.8
163
5.5
41.0
Dec 16, 2004
3,136
1.94
22.1
544
23.8
44.6
Jan 17, 2005
nd
nd
nd
nd
nd
nd
Jan 19, 2005
1,455
1.02
16.4
194
10.2
96.5
Apr 23, 2005
3,147
1.60
37.6
945
26.2
38.6
June 06, 2005
nd
nd
nd
nd
nd
nd
July 27, 2005
744
0.23
8.8
146
3.3
46.6
Aug 08, 2005
nd
nd
nd
nd
nd
nd
Aug 08, 2005
693
0.30
6.0
121
5.0
40.0
Sept 25, 2005
1,410
0.90
10.0
243
8.0
70.0
Sept 29, 2005
2,214
1.20
12.0
345
11.0
94.0
Oct 28, 2005
nd
nd
nd
nd
nd
nd
Oct 28, 2005
545
0.20
16.0
128
7.2
35.3
July 07, 2005
386
<0.1
12.9
91
3.6
42.4
May 16, 2006
4,688
<0.4
22.1
179
13.8
126
