2017 Water Utilities Consumer Confidence Report 2017 Water Utilities Consumer Confidence Report | Page 3

Arlington Water Utilities tests drinking water at over 120 sample sites all over the
city each month. In 2017, the laboratory collected 7,327 samples and performed
16,829 tests monitoring 229 different analytes. This report contains data
collected from Jan. 1, 2017 through Dec. 31, 2017, unless another time frame is noted.
Here’s a little more about the laboratory team that performs that work.
Water Utilities Laboratory by the Numbers:
Combined years
of lab experience
Full-time
staff
7
4
124
Part-time
staff
Master’s degrees –
2 chemistry, 1 education
9
3
TCEQ Water Operator licenses
(3 Class A, 3 Class B, 1 Class C and 2 Class D)
6
Bachelor’s degrees -
5 biology, 1 geology
Arlington Water Utilities Lab Staff
Table B. Unregulated Substances. These substances are not
currently regulated by EPA . The purpose of unregulated contaminant monitoring
is to assist EPA in determining the occurrence of unregulated contaminants in
drinking water and whether future regulation is warranted.
Substance
Chloroform
Bromodichloromethane
Chlorodibromomethane
Bromoform
Dichloroacetic Acid
Bromoacetic Acid
Dibromoacetic Acid
Chloroacetic Acid
Trichloroacetic Acid
Units Avg.
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
3.5
3.3
3.2
0.3
4.64
3.08
5.38
1.5
0.19
Min. Max. MCL
2.4
3.0
3.0
0.2
3.06
2.71
1.28
0.78
0.02 4.3
3.6
3.4
0.5
5.88
4.03
8.53
2.01
0.44 Not Regulated
Not Regulated
Not Regulated
Not Regulated
Not Regulated
Not Regulated
Not Regulated
Not Regulated
Not Regulated
Action Level (AL) The
concentration of a contaminant
which, if exceeded, triggers
treatment or other requirements
which a water system must
follow.
< less than the amount listed.
≥ equal to or greater than the
amount listed.
Maximum Contaminant Level
Goal (MCLG) The level of a
contaminant in drinking water
below which there is no known
or expected risk to health.
MCLGs allow for a margin of
safety.
Other Substances of Interest
Substance
MCLG Possible Source
NE
NE
60
NE
NE
NE
NE
NE
300
By-product of drinking
water disinfection; not
regulated individually;
included in Total
Trihalomethanes.
By-product of drinking
water disinfection; not
regulated individually;
included in Haloacetic
Acids.
Maximum Contaminant Level
(MCL) The highest level of a
contaminant that is allowed
in drinking water. MCLs are
set as close to the MCLGs as
feasible using the best available
treatment technology.
Maximum Residual Disinfectant
Level Goal (MRDLG) The
level of a drinking water
disinfectant below which there
is no known or expected risk
to health. MRDLGs do not
reflect the benefits of the use
of disinfectants to control
microbial contamination.
Units Avg ppm
ppm
grains/gal.
ppm 84.5
89.3
5.2
33 44
50
2.9
16 Sodium ppm 19.9 10.2 27
Magnesium ppm 3.6 2.7 4.5
Chloride
Total:
Alkalinity
Hardness
Hardness
Calcium
Min Max
119
150
6.1
41
ppm 15 10 22
Total Dissolved
Solids ppm 132 96 169
pH units 8.2 7.7 8.6
Maximum Residual Disinfectant
Level (MRDL) The highest
level of a disinfectant allowed
in drinking water. There is
convincing evidence that
addition of a disinfectant
is necessary for control of
microbial contaminants.
NA Not applicable
ND (Not Detected) No level of
the parameter was detected.
NE Not established
NTU (Nephelometric Turbidity
Units) A unit used when
measuring turbidity, a measure
of the cloudiness of the water.
pCi/L (picocuries per Liter) A
measure of radioactivity in the
water.
ppb (parts per billion, ug/L) A
unit of measurement roughly
equal to 1 drop in 100,000
gallons.
ppm (parts per million, mg/L)
A unit of measurement roughly
equal to 1 drop in 100 gallons.
TT (Treatment Technique)
A required process intended
to reduce the level of a
contaminant in drinking water.
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