Upper Souris WUA-System I Has Levels of Total Trihalomethanes (TTHMs) and Haloacetic Acids (HAA5s) Above Drinking Water Standards
Our water system recently violated two drinking water standards. Although this is not an emergency, as our customers, you have a right to know what happened, what you should do, and what we are doing to correct this situation.
We routinely monitor for the presence of drinking water contaminants. Testing results we received on 3/8/05 show that our system exceeds the standard, or maximum contaminant level (MCL) for Total Trihalomethanes (TTHMs). The standard for TTHMs is .080 milligrams per Liter (mg/L). The average level of TTHMs for this year was .377 mg/L.
These tests results also indicate that our system also exceeds the standard or MCL for Haloacetic Acids (HAA5s). The standard for HAA5s is .060 milligrams per Liter (mg/L). The average level of HAA5s for this year was .066 mg/L.
What should I do?
You do not need to use an alternative (e.g. bottled) water supply. However, if you have specific health concerns, please consult your doctor.
What does this mean?
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.
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.
What happened? What is being done?
The proposed plan of action to reduce TTHM and HAA5 concentrations in the distribution system is to switch the secondary disinfectant from free chlorine to chloramines (through the addition of chlorine and ammonium sulfate) immediately after filtration. Chloramines are a generally less reactive disinfectant than chlorine, a reduction in TTHMs and HAA5s concentrations should be realized.
We plan on switching disinfectants during the week of April 25th, 2005. We will continue to monitor TTHMs and HAA5s concentrations throughout our distribution system to ensure teh disinfectant switch produces the desired result of reducing the average TTHM and HAA5 concentrations below their respective MCL's. If the desired result is not achieved by switching disinfectants, we will evaluate various disinfection by-product precursor removal technologies (granular activated carbon, ozone, membranes, etc.) as part of a second phase improvement process.
For more information on the disinfection byproduct rule and health effects check the EPA?s website @ www.gov/enviro/html/icr/dbp_health.html This information and notice is also available on Upper Souris? website @ http:// www.oocities.org/uppersouriswater/index.html
For more information, please contact ( Gary Hager , (701) 385-4093 or PO Box 397, Kenmare, ND, 58746)
Date of Notice: April 19, 2005
Upper Souris WUA- System II Has Levels of Total Trihalomethanes (TTHMs) Above Drinking Water Standards
Our water system recently violated a drinking water standard. Although this is not an emergency, as our customers, you have a right to know what happened, what you should do, and what we are doing to correct this situation.
We routinely monitor for the presence of drinking water contaminants. Testing results we received on 3/8/05 show that our system exceeds the standard, or maximum contaminant level (MCL) for Total Trihalomethanes (TTHMs) is .080 milligrams per Liter (mg/L). The average level of TTHMs for this year was .517mg/L.
What should I do?
You do not need to use an alternative (e.g. bottled) water supply. However, if you have specific health concerns, please consult your doctor.
What does this mean?
Some people who drink water containing Trihalomethanes 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.
What happened? What is being done?
The proposed plan of action to reduce TTHM and HAA5 concentrations in the distribution system is to switch the secondary disinfectant from free chlorine to chloramines (through the addition of chlorine and ammonium sulfate) immediately after filtration. Chloramines are a generally less reactive disinfectant than chlorine, a reduction in TTHMs and HAA5s concentrations should be realized.
We plan on switching disinfectants during the week of April 25, 2005. We will continue to monitor TTHMs and HAA5s concentrations throughout our distribution systems to ensure the disinfectant switch produces the diesired result of reducing the average TTHM and HAA5 concentrations below their respective MCL's. If the desired result is not achieved by switching disinfectants, we will evaluate various disinfection by-product precursor removal technologies (granular activated carbon, ozone, membranes, etc.) as part of a second phase improvement process.
For more information on the disinfection byproduct rule and health effects check the EPA's website www.gov/enviro/html/icr/dbp_health.html
This information and notice is also available on Upper Souris website@ http://www.oocities.org/uppersouriswater/index.html
For more information please contact (Gary Hager, (701) 385-4093, or PO Box 397, Kenmare ND 58746)
Date of Notice: April 19, 2005
What is Disinfection?
Disinfection is usually a chemical process used in water systems which either chemicals are added to inactivate (or kill) pathogens (i.e., disease causing organisms) found in the source water (i.e., lake, river, reservoir, or ground water aquifer from which water is drawn and treated). Disinfection through inactivation usually involves the use of disinfectants such as chlorine, ozone, and chlorine dioxide, and a combination of chlorine and ammonia (chloramines) may render many of these organisms harmless.
What are Disinfection Byproducts?
Disinfection byproducts are formed when disinfectants used in a water treatment react with bromide and/or natural organic matter (i.e., decaying vegetation) present in the source water. Different disinfectants produce different types or amounts of disinfection byproducts. Disinfection byproducts for which regulations have been established have been identified in drinking water, including trihalomethanes, haloacetic acids, bromate, and chlorite.
What Regulations Control Disinfection Byproducts?
In December 1998, EPA published the Stage 1 Disinfectants/Disinfection Byproducts Rule that requires water systems to use treatment methods to reduce the formation of disinfection byproducts and to meet the following standards: total trihalomethanes (TTHM)(measured as the sum concentration of chloroform, bromoform, bromodichloromethane, and dibromochloromethane) at 80 parts per billion (ppb), haloacetic acids (HAA5) (measured as the sum concentration of monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid, and dibromoacetic acid) at 60 ppb, bromate at 10 ppb, and chlorite at 1.0 parts per million (ppm). The standards for TTHM, HAA5, and bromate are annual averages. For chlorite, the standard is an average of a three samples taken at least monthly. Data from the ICR and research will be used to consider further disinfection byproduct control under a Stage 2 Disinfectants/Disinfection rule, scheduled to be published in May 2002.
How are Disinfection Byproducts and Pathogens Related?
Current disinfection methods used in water systems can inactivate pathogens, but can also form disinfection byproducts that may be harmful to human health. EPA's job in regulating disinfection byproducts is to develop requirements for water treatment that will both protect people from waterborne disease and the potential harmful effects of disinfection byproducts. The ICR will provide some of the information to address this issue.
Disinfection byproducts are formed when disinfectants used in water treatment plants react with bromide and/or natural organic matter (i.e., decaying vegetation) present in the source water. Different disinfectants produce different types or amounts of disinfection byproducts. Disinfection byproducts for which regulations have been established have been identified in drinking water, including trihalomethanes, haloacetic acids, bromate, and chlorite.
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Tihalomethanes (THM) are a group of four chemicals that are formed along with other disinfection byproducts when chlorine or other disinfectants used to control microbial contaminants in drinking water react with naturally occurring organic and inorganic matter in water. The trihalomethanes are chloroform, bromodichloromethane, dibromochloromethane, and bromoform. EPA has published the Stage 1 Disinfectants/Disinfection Byproducts Rule to regulate total trihalomethanes (TTHM) at a maximum allowable annual average level of 80 parts per billion. This standard will replace the current standard of a maximum allowable annual average level of 100 parts per billion in December 2001 for large surface water public water systems. The standard will become effective for the first time in December 2003 for small surface water and all ground water systems.
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Haloacetic Acids (HAA5) are a group of chemicals that are formed along with other disinfection byproducts when chlorine or other disinfectants used to control microbial contaminants in drinking water react with naturally occurring organic and inorganic matter in water. The regulated haloacetic acids, known as HAA5, are: monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid, and dibromoacetic acid. EPA has published the Stage 1 Disinfectants/Disinfection Byproducts Rule to regulate HAA5 at 60 parts per billion annual average. This standard will become effective for large surface water public water systems in December 2001 and for small surface water and all ground water public water systems in December 2003.
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Bromate is a chemical that is formed when ozone used to disinfect drinking water reacts with naturally occurring bromide found in source water. EPA has established the Stage 1 Disinfectants/Disinfection Byproducts Rule to regulate bromate at annual average of 10 parts per billion in drinking water. This standard will become effective for large public water systems by December 2001 and for small surface water and all ground public water systems in December 2003.
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Chlorite is a byproduct formed when chlorine dioxide is used to disinfect water. EPA has published the Stage 1 Disinfectants/Disinfection Byproducts Rule to regulate chlorite at a monthly average level of 1 part per million in drinking water. This standard will become effective for large surface water public water systems in December 2001 and for small surface water and all ground water public water systems in December 2003.
Since the discovery of chlorinating byproducts in drinking water in 1974, numerous toxicological studies (studies on the health effects from exposure to high dosages contaminants usually involving animals in a lab) have been conducted. These studies have shown several disinfection byproducts to be carcinogenic in laboratory animals (e.g., including bromate, certain trihalomethanes and haloacetic acids). Some disinfection byproducts have also been shown to cause adverse reproductive or developmental effects in laboratory animals (e.g., chlorite and certain trihalomethanes and haloacetic acids). However, there is considerable uncertainty involved the results of high-dose, toxicological studies of some byproducts occurring in disinfected drinking water to estimate the risk to humans from chronic exposure to low doses of these and other byproducts.
In the area of epidemiology (studies of the factors that influence disease in human populations), a number of studies have been completed investigating the relationship between exposure to chlorinated surface water and cancer. Some have suggested an increased cancer risk to those exposed to chlorinated waters while others have demonstrated none. In issuing the Stage 1 Disinfectants/Disinfection Byproducts Rule based on evidence then available, EPA stated that while the agency cannot conclude there is a causal link between exposure to chlorinated surface water and cancer, these studies have suggested an association, albeit small, between bladder, rectal, and colon cancer and exposure to chlorinated surface water. There are fewer epidemiology studies evaluating the association between exposure to disinfection byproducts and reproductive and developmental effects. Again, some have suggested an increased risk from exposure to disinfection byproducts while others have shown none. There remains considerable debate in the scientific community on the significance of these contradictory findings concerning chlorinated water and disinfection byproducts. As with cancer, EPA stated in its Stage 1 Disinfectants/Disinfection Byproducts Rule that, based on data then available, the agency can not conclude there is a causal link between exposure to disinfection byproducts and reproductive and developmental effects. In sum, EPA believes the weight-of-evidence presented by the available epidemiological studies on chlorinated drinking water and toxicological studies on individual disinfection byproducts support a potential hazard concern and warrant regulatory action at this time such as that taken in the Stage 1 Disinfectants/Disinfection Byproducts Rule.
An extensive research effort (1997 Update to ORD's Strategic Plan, National Toxicology Program) is currently underway to better understand the potential risks attending exposure to disinfection byproducts. While this research is being completed, an agreement among water suppliers, environmental groups, consumer groups, and regulatory agencies has been reached, resulting in the publication of a Stage 1 Disinfectants/Disinfection Byproducts Rule by EPA in the Federal Register in December 1998. The participants recommended that while additional information, especially on health effects, is needed, the Stage 1 Disinfectants/Disinfection Byproducts Rule was considered the best course of action to reduce potential risks from disinfection byproducts in the near term.