Page 4 - Clinton Currents Volume XIX Issue 2 - Spring/Summer 2019
P. 4
Page 4 Spring/Summer 2019
GLWA Water System: 2018 test results, detected contaminants
Results represent a combination of contaminants reported by the Northeast and Lake Huron water treatment plants. The levels con rm that our water meets all state and federal guidelines for drinking water.
Contaminant
Test Date
Units
Health Goal MCLG
Allowed Levels MCL
Highest Level Detected
Range
of Detection
Violation
Likely Source
2018 Disinfection By-Products – Monitoring in Distribution System, Stage 2 Disinfection By-Products
Total Trihalomethanes (TTHM)
Haloacetic Acids (HAA5)
Jan Dec 2018
Jan Dec 2018
ppb ppb
N/A N/A
80 60
32.5 12.5
11.7 – 33.8 8–16
No No
By-product of drinking water chlorination
By-product of drinking water disinfectant
2018 Disinfectant Residuals – Monitoring in Distribution System by Treatment Plants
Total Chlorine Residual
Jan Dec 2018
ppm
4
4
0.73
0.68-077
No
Water additive used to control microbes
2018 Turbidity – Monitored every 4 hours at Plant Finished Water
Highest Single Measurement Can not exceed 1 NTU
Lowest Monthly % of Samples Meeting Turbidity Limit of 0.3 NTU (minimum 95%)
Violation Yes/No
Major Source in Drinking Water
.20NTU
100%
No
Soil Runoff
Turbidity is a measure of the cloudiness of water. We monitor it because it is a good indicator of the effectiveness of our filtration system.
2018 Microbiological Contaminants - Monthly Monitoring in Detroit and Mount Clemens Distribution Systems
Contaminant
MCLG
MCL
Highest
Number Detected
Violation Yes/No
Major Sources in Drinking Water
Total Coliform
0
Presence of Coliform bacteria in 5% of monthly samples
In one month 0
No
Naturally present in the environment
E. coli or fecal coliform bacteria
0
A routine sample and a repeat sample are total coliform positive, and one is also fecal or E. Coli positive
Entire year 0
No
Human waste and animal fecal waste
Clinton Township lead and copper results
2017 Lead and Copper Monitoring at Customer’s Tap
Contaminant
Test Date
Units
Health Goal MCLG
Action Level AL
90th Percentile Value*
Number of of Samples Over AL
Violation
Major Sources in Drinking Water
Lead
2017
ppb
0
15
0.0
0
No
Corrosion of household plumbing systems; Erosion of natural deposits.
Copper
2017
ppm
1.3
1.3
0.1
0
No
Corrosion of household plumbing systems; Erosion of natural deposits; leaching from wood preservatives.
* The 90th percentile value means 90 percent of the homes tested have lead and copper levels below the given 90th percentile value. If the 90th percentile value is above the AL additional requirements must be met.
Unregulated contaminants are those for which EPA has not established drinking water standards. Monitoring helps EPA to determine where these contaminants occur and whether it needs to regulate those contaminants. To the right is the report of unregulated contaminants detected during quarterly sampling and analysis performed in 2015 and 2018.
The tables in this report list detected contaminant levels in the water we use.
Unregulated Contaminant
Strontium
Vanadium
Chromium (Total)
Chromium-6
Total Haloacetic Acids UCMR4
Test Date
Jan – Dec 2015
Jan – Dec 2015
Jan – Dec 2015
Jan – Dec 2015
May – Nov 2018
Units
ppb
ppb
ppb
ppb
ppb
Reference Concentration From EPA
1,500
21
100
N/A
N/A
Average Level Level Detected
102
0.59
0.2
0.13
23
Range
of Detection
90 – 110
0.45 – 0.68
0.2 – 0.34
0.03 – 0.19
16 – 34
VV