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UCMR Page for Canton: 2020
Massachusetts Water Resources Authority
Research for New Regulations
The US Environmental Protection Agency (EPA) periodically requires water systems across the country to conduct monitoring for substances that may be present in drinking water to help understand their national occurrence as part of the process of deciding whether to regulate them. Under the Safe Drinking Water Act Amendments, EPA established the Unregulated Contaminant Monitoring Rule and is required once every five years to develop a list of up to 30 new contaminants that must be monitored during a three year period by public water systems that meet the criteria for sampling. This monitoring is used by EPA to understand the frequency and level of occurrence of unregulated contaminants in the nation’s public water systems (PWSs).
EPA will collect and analyze data for all three years and from systems all across the country to develop an understanding of the occurrence, level and distribution of these substances in drinking water. That data, along with information on potential health effects and water treatment effectiveness will be used by EPA to determine if any new regulations are needed.
2020 UCMR Test Results for Canton
| Substance | Measurement Units | Average | Range |
|---|---|---|---|
| Manganese | parts per billion (ppb) | 3.5 | 0.47 - 7.2 |
Manganese is a common mineral that naturally occurs in rocks and soil, and is commonly found in ground and surface waters in New England. It may also be present due to underground pollution sources. Manganese is an essential mineral for proper digestion, bone development, and immune function. Primary sources in the diet include grains, beans, nuts and teas. At excessively high levels, however, manganese can have adverse neurological effects. EPA has a secondary, aesthetic standard of 50 ppb. Above the 50 ppb level, consumers may notice a gray or black coloring in their water and/or fixture staining. To be protective of public health MassDEP has a health guideline value of 300 ppb, and Consumer Confidence Report Notification Limit of 50 ppb. Canton's results are well below the state and EPA health and aesthetic standards. |
|||
| Substance | Measurement Units | Average | Range |
|---|---|---|---|
| Quinoline | parts per billion (ppb) | 0.006 | 0 - 0.023 |
Quinoline is a naturally occurring substance found in coal and is a component of coal tar and petroleum. It is used in the manufacture of dyes, pharmaceuticals and some personal care products, and is present in some foods and beverages. Quinoline is present in tobacco smoke, which is a significant source of exposure for people who smoke and people exposed to secondhand smoke. Given the uncertainty in health effects, EPA provides a wide range for its health reference level (HRL), from 0.01 to 1 ppb. Minnesota has published a non-regulatory guidance value of 0.03 ppb. The average quinoline levels in Canton are low based on the HRL. |
|||
| Substance | Measurement Units | Average | Range |
|---|---|---|---|
| HAA5 | ppb | 7.95 | 2.71 - 17.30 |
| HAA6Br | ppb | 3.28 | 0 - 7.9 |
| HAA9 | ppb | 10.52 | 5.09 - 19.2 |
| Bromochloroacetic Acid | ppb | 1.54 | 0.51 - 2.94 |
| Bromodichloroacetic Acid | ppb | 0.55 | 0 - 1.8 |
| Chlorodibromoacetic Acid | ppb | 0.48 | 0 - 1.1 |
| Haloacetic acids (HAA) are a group of disinfection byproducts that form when chlorine compounds that are used to disinfect water react with other naturally occurring material in the water. There are five significant HAAs potentially found in disinfected drinking water and their combined concentration is referred to as HAA5. HAA5s are already regulated by the EPA and MassDEP and have a Maximum Contaminant Level (MCL) standard of 60 ppb as a locational running annual average. Levels for HAA5 in Canton drinking water are below the MCL. Tribromoacetic acid was not present in Canton water samples in 2020. HAA9 and HAA6Br include four more HAA compounds that are not currently regulated by EPA or MassDEP. If all 9 species in the HAA9 group were combined, Canton would still be well below the current HAA5 MCL of 60 ppb, with an average of around 10.52 ppb. | |||
How will this data be used?
EPA will collect and analyze data for all three years and from systems all across the country to develop an understanding of the occurrence, level and distribution of these substances in drinking water. That data, along with information on potential health effects and water treatment effectiveness will be used by EPA to determine if any new regulations are needed.