|
1975 – 1985 (132 months)
|
|---|
|
Contaminant
|
Mean (μg/L)
|
Median (μg/L)
|
Range (μg/L)
|
# Months >MCL
|
# Months >100 μg/L
|
|---|
|
Tetrachloroethylene
|
75.7
|
84.9
|
0 – 158.1
|
117
|
16
|
|
Trichloroethylene
|
3.1
|
3.5
|
0 – 6.6
|
11
|
0
|
|
Vinyl chloride
|
5.6
|
6.2
|
0 – 12.3
|
117
|
0
|
|
1975 – 1979 (60 months)
|
|
Tetrachloroethylene
|
68.3
|
68.2
|
43.8 – 94.8
|
60
|
0
|
|
Trichloroethylene
|
2.8
|
2.9
|
1.7 – 3.9
|
0
|
0
|
|
Vinyl chloride
|
5.2
|
5.5
|
2.6 – 7.3
|
60
|
0
|
|
January 1980 – January 1985 (61 months)*
|
|
Tetrachloroethylene
|
96.1
|
95.5
|
0¥ – 158.1
|
57
|
16
|
|
Trichloroethylene
|
3.9
|
3.9
|
0¥ – 6.6
|
11
|
0
|
|
Vinyl chloride
|
7.0
|
7.0
|
0¥ – 12.3
|
57
|
0
|
- *Two contaminated wells were shut down in January 1985. Estimated monthly average tetrachloroethylene levels from February through December 1985 were <4 μg/L.
-
¥One contaminated well was shut down for maintenance during 7/80 – 8/80 and 1/83 – 2/83. The other contaminated well was not in use until August 1984.
