IMPORTANT INFORMATION ABOUT YOUR DRINKING WATER
To all users of the Millville Elementary School located in Millville, Massachusetts Haloacetic Acids (HAA5) and Total Trihalomethanes (TTHMs) are Above Drinking Water Standards
This is an important notice - please translate it for anyone who does not understand English. |
This notice is to advise our customers that our water system is in noncompliance with the drinking water standards for Haloacetic Acids (HAA5) and Total Trihalomethanes (TTHM) which are by-products of chlorination. Although this is not an emergency, you have a right to know what happened, what you should do, and what we are doing to correct this situation.
We are required to monitor the drinking water for HAA5s and TTHM levels on a routine basis. The standard or maximum contaminant level (MCL) for HAA5s is 60 parts per billion (ppb), and compliance is determined on a quarterly basis by averaging all samples collected at each location for the last 12 months (Locational Running Annual Average or LRAA). Previous notifications were issued reporting that the sample results of Q2, Q3 of 2022 and Q1, Q2, Q3 of 2023 showed that our system exceeded the MCL for HAA5s during those compliance periods. The results of the last four quarters’ samples (ranging between 18 and 250 ppb) show that the LRAA exceeded the standard or maximum contaminant level (MCL) for HAA5s during the October through December (Q4) 2023 compliance period. Individual samples collected during the October through December 2023 compliance period reported levels between 20 and 42 ppb, however the LRAA remains above the MCL. The locations and LRAA compliance averages are as follows (averages above the MCL have been highlighted):
| HAA5 Locational Running Annual Average (LRAA) (ppb) |
| |||||||||
| Location | Q2 Apr-Jun 2022 | Q3 Jul-Sep 2022 | Q4 Oct-Dec 2022 | Q1 Jan-Mar 2023 | Q2 Apr-Jun 2023 | Q3 Jul-Sep 2023 | Q4 Oct-Dec 2023 | HAA5 MCL | |
| DBP1 – Room 113/111 | 64 | 65 | 57 | 71 | 82 | 80 | 75 | 60 | |
| DBP2 – Room 308/322 | 59 | 60 | 59 | 71 | 67 | 69 | 62 | 60 | |
The standard or maximum contaminant level (MCL) for TTHMs is 80 parts per billion (ppb), and compliance is determined on a quarterly basis by averaging all samples collected at each location for the last 12 months (Locational Running Annual Average or LRAA). A previous notification was issued reporting that the sample results of Q3 (Jul – Sep) of 2023 showed that our system exceeded the MCL for TTHMs during the compliance period. The results of the last four quarters’ samples (ranging between 14 and 160 ppb) show that the LRAA exceeded the standard or maximum contaminant level (MCL) for TTHMs during the October through December (Q4) 2023 compliance period. Individual samples collected during the October through December 2023 compliance period reported levels between 36 and 60 ppb, however the LRAA remains above the MCL. The locations and LRAA compliance averages are as follows (averages above the MCL have been highlighted):
| TTHM Locational Running Annual Average (LRAA) (ppb) |
| ||||||
| Location | Q1 Jan-Mar 2023 | Q2 Apr-Jun 2023 | Q3 Jul-Sep 2023 | Q4 Oct-Dec 2023 | THM MCL | |
| DBP1 – Room 111 | 71 | 73 | 92 | 91 | 80 | |
| DBP2 – Room 308/322 | 77 | 77 | 90 | 89 | 80 | |
What does this mean?
This is not an immediate risk. If it had been, you would have been notified right away.
- Some people who drink water containing haloacetic acids (HAA5s) in excess of the MCL over many years may have an increased risk of getting cancer.
- Some people who drink water containing trihalomethanes (TTHMs) in excess of the MCL over many years may experience problems with their liver, kidneys, or central nervous system, and may have an increased risk of getting cancer.
In addition, young children (including infants), pregnant women or those who may become pregnant may be potentially more susceptible to risks from exposures to chemicals, such as TTHMs and HAA5s.
What happened?
HAA5s and TTHMs are byproducts of chlorine which form when chlorine (a disinfectant and oxidant) combines with natural organic matter commonly found in surface and ground water supplies. Levels can vary depending on a number of factors including the amount of chlorine used, amount of organic plant material in water sources, temperature, water age and seasons. We must control these by-product levels while also maintaining appropriate levels of chlorine in the water necessary to remove contaminants (iron and manganese) and to avoid potential bacterial issues. Our water system has been required by MassDEP to submit a plan containing immediate short-term and long-term actions to correct the issue.