Table 3 (cont'd).
f. Nickel
g. Zinc
Contact time, days
Contact time, days
Treatment
1
5
20
40
Treatment
1
5
20
40
CONTROL
3.33
3.40
5.38
5.00
CONTROL
LD
0.72
LD
0.99
CONTROL
3.41
3.42
5.45
5.23
CONTROL
LD
LD
LD
1.14
CONTROL
3.42
3.49
5.22
5.33
CONTROL
LD
0.87
LD
0.97
1.03a
3.39a
3.44a
5.35a
5.18a
X
<0.66
<0.75
<0.66
X
% RSD
--
--
--
8.74
% RSD
1.47
1.45
2.24
3.28
PVC
0.71
0.93
0.91
1.16
PVC
8.41
14.0
18.0
11.0
PVC
LD
0.77
0.69
1.69
PVC
6.51
11.2
11.0
21.0
PVC
0.83
0.99
0.96
1.33
PVC
7.48
10.7
16.6
18.1
0.90a
0.85a
1.39a,b
7.46b
12.0c
15.2c
16.7b
X
<0.73
X
% RSD
--
12.2
16.5
19.4
% RSD
12.7
15.0
24.2
31.1
PTFE
0.78
0.90
0.82
1.17
PTFE
6.30
5.36
12.1
10.0
PTFE
1.08
1.13
0.67
1.14
PTFE
8.51
7.02
8.48
9.73
PTFE
0.71
1.08
0.96
1.13
PTFE
5.07
5.59
14.2
10.5
0.86a
1.04a
0.82a
1.15a
6.63b
5.99b
11.6b,c
10.1a
X
X
% RSD
23.3
11.5
18.3
1.74
% RSD
26.2
15.0
24.9
3.67
FEP
0.86
1.01
0.56
1.38
FEP
5.65
7.86
9.03
7.84
FEP
1.61
1.05
1.03
1.45
FEP
5.26
5.49
10.5
8.79
FEP
1.12
1.34
1.05
2.32
FEP
7.20
7.41
7.39
8.79
1.20a,b
1.13a
0.88a
1.72b,c
6.03b
6.92b
8.98a,b
8.48a
X
X
% RSD
31.7
15.9
31.8
30.2
% RSD
17.1
18.2
17.5
6.49
FRE
1.32
1.62
1.24
2.31
FRE
8.57
10.7
11.4
17.8
FRE
2.23
1.58
1.17
2.27
FRE
7.38
12.2
12.6
19.7
FRE
2.36
1.75
2.09
1.81
FRE
7.89
10.6
12.6
10.5
1.97b,c
1.65b
1.50b
2.13c
7.94b
11.2c
12.2b,c
16.0b
X
X
% RSD
28.9
5.45
34.0
13.2
% RSD
7.56
7.80
5.50
30.5
FRP
2.83
2.29
2.12
1.92
FRP
22.3
39.5
36.1
44.7
FRP
1.62
1.72
1.67
2.49
FRP
25.2
38.4
37.0
44.1
FRP
2.38
2.29
1.74
2.13
FRP
22.2
40.9
44.7
43.3
2.28c
2.10c
1.84b
2.18c
23.2c
39.6d
39.3d
44.0c
X
X
% RSD
26.8
15.7
13.0
13.3
% RSD
7.32
3.21
12.1
1.23
LD Values less than MDL.
Values with the same letter for the same time were not signifi-
Values with the same letter for the same time were not signifi-
cantly different.
cantly different.
of Cu, with ~50% loss by the end of the study. In
Even though leached concentrations were high-
comparison, losses by the end of the study were
est in samples exposed to FRE and FRP, these con-
32% for PVC and 20% for FEP.
centrations were generally well below levels
In a similar study, Hewitt (1989) found SS 316
Hewitt (1989) observed leaching from SS 304 and
casings leached significant quantities of copper;
316 casings and screens under similar conditions.
mean concentrations of leached Cu were 3 to 8
times background values.
Copper
The initial Cu concentration of the groundwa-
ter used in this study was approximately 18 g/L
Lead
For the control samples, lead concentrations
(Table 3d). Table 4 clearly shows that none of the
were all less than the MDL (Table 3e). Only sam-
materials leached Cu but rather, with the excep-
tion of PTFE, sorbed significant quantities. It was
ples exposed to the FRP casings consistently had
Pb concentrations above the MDL. Normalized
surprising that FEP sorbed 10 to 20% of the cop-
concentrations for samples exposed to FRP ranged
per while PTFE did not, since we expected the
from 22 to 34 times control values (Table 4). In
two fluoropolymers to perform similarly. The two
several samples, concentrations approached or ex-
fiberglass materials showed the greatest sorption
7
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