The recent news that per- and polyfluoroalkyl substances (PFAS) have been found in four public water supplies and two private wells in Harvard may have left residents wondering what testing is currently required for the drinking water drawn from public and private sources.
Only about 50 of Harvard’s 1750 single-family houses rely on public water; the rest have private wells, which, once installed, have no testing requirements until a property is sold. That leaves most residents on their own to figure out what to test for and how often, and the recommendations of the state and Harvard’s Board of Health differ slightly, mainly in test frequency.
Testing public water supplies
The Massachusetts Department of Environmental Protection (MassDEP) governs drinking water tests from public water supplies. The state mandates that any business or institution that serves 25 or more people for 60 or more days a year must have a public water system, and it dictates what contaminants must be tested for, the maximum contaminant level (see Levels vs. Guidelines on this page) and how often they must be tested for. The list includes bacteria, lead and other heavy metals, radioactive substances, herbicides and pesticides, and industrial solvents. MassDEP also strongly recommends annual testing of public water supplies for substances such as iron that may affect the taste, color, or odor of drinking water.
Harvard has both a municipal public water supply that serves the water district—an area around the center of town—and 15 smaller public water supplies that serve residential complexes, schools, and businesses outside the district. Harvard’s water district includes the schools and municipal buildings, three churches, a handful of businesses, and a few dozen residences. Harvard’s smaller public water supplies serve Foxglove Apartments, Harvard Green condominiums, and Trail Ridge condominiums, as well as St. Benedict Abbey, Immaculate Heart of Mary School, Village Nursery School, Friendly Crossways, Fruitlands Museum, Camp Green Eyrie, and some of the businesses in the commercial zone on Ayer Road.
The Department of Public Works (DPW) tests the town wells for more than 100 contaminants identified by MassDEP, including some that affect only the aesthetic qualities of the town’s water. The DPW posts a drinking water quality report that includes town water test results annually on the town website. However, the owners of the 15 public water sources are responsible for those water supplies on a regularly scheduled program developed by MassDEP.
Testing private water supplies
Harvard’s Board of Health (BOH) governs drinking water tests on the town’s private wells. Private wells serve not only 97 percent of the residences in town, but also about a dozen buildings in the commercial zone. The frequency of drinking water testing on private wells is at the discretion of the property owner. The BOH requires testing only when the well is constructed, has a major repair, or when the property is sold.
The BOH requires tests for bacteria, heavy metals, and radioactive substances in new wells or before a property sale. Regulations also include testing for substances that could affect the aesthetic qualities of the water. But the tests for herbicides, pesticides, and industrial solvents that are required for public water supplies are not required by the BOH for private wells.
While MassDEP recommends at least an initial test for industrial solvents, which are in a class of chemicals called volatile organic compounds, Harvard’s Health Agent Ira Grossman said he doesn’t agree with that recommendation. He said tests for those substances are expensive and unlikely to yield positive results in a rural area such as Harvard, where there are few sources of industrial contamination.
Board of Health regulations specify that the board could require testing of any private wells suspected of contamination, and Grossman told the Press he considers the history of a site to determine if further testing for specific substances, such as those found in pesticides, is necessary when a well is first installed. He added that if an event such as an oil spill occurred, the state would become involved and, if appropriate, declare a hazardous site. Such a declaration would include mandatory testing of public and private wells in a defined area around the site.
What about PFAS?
If the state defines a maximum contaminant level for the family of substances known as PFAS (see PFAS in the News), it would likely require testing of public water supplies, especially in areas that have already tested positive for PFAS. But private wells do not have to be tested for substances with defined maximum contaminant levels, either when a well is constructed or when a property is sold. The state has set maximum contamination levels for 88 substances, but it recommends that private well owners test for only eight of those plus volatile organic compounds, a category that includes 22 separate substances (see table).
Since PFAS are already known to exist in some smaller Harvard public water supplies, would the state require testing of private wells in those areas? According to Grossman, no. That would be up to the BOH. MassDEP’s policy is that contamination of any type found in a public water supply does not require notification of private well owners in the area, so that would also be up to the BOH.
But, while state regulations specify that property owners must notify the public if their water violates drinking water standards, that information is not always conveyed to Harvard’s BOH in a timely manner. Grossman said it sometimes receives notices from property owners, but not always. The state eventually notifies the BOH, but he said that can take as long as 18 months. He added that while he does eventually see the reports, action is not typically warranted, since most contaminants, such as coliform bacteria, don’t travel from one property’s water supply to another. In most cases, Grossman said, the chance of impact on a neighboring water supply would be “infinitesimal.” But PFAS test results have shown clusters of contamination, which could require better coordination between MassDEP and local boards of health.
If a maximum PFAS level is set by the federal government or state, Grossman said the board would contact the state and discuss what, if any, action to take on its private well regulations. He said that action would likely depend on where the PFAS exceeded maximum levels. And, he said, either MassDEP or the Army would likely do further testing to try to determine the source of the contamination. While firefighting foam, used at Fort Devens, is considered a major source of PFAS contamination in groundwater, Grossman said there could be other sources. For instance, across the street from the Ayer Road Properties buildings at 188-200 Ayer Road, which tested positive for PFAS last summer, there was a machine shop that closed in the early 1980s. Machine shops are a possible source of PFAS contamination.
Additional reading
- MassDEP: Protect Your Family: A Guide to Water Quality Testing for Private Wells. Contains MassDEP’s recommendations for private well water tests.
- MassDEP: Private Well Guidelines: Everything you need to know about private wells. Appendix B contains a table of land use activities linked to potential contaminants.
- MassDEP: What’s in my drinking water? Resources for information about public and private drinking water testing in Massachusetts.
- Harvard BOH website: Information on arsenic, radionuclides, PFAS, and water testing.
- Massachusetts Executive Office of Energy and Environmental Affairs Data Portal: Test results of all public water supply tests in Harvard and other Massachusetts towns.
Limits vs. Guidelines
The Environmental Protection Agency (EPA) sets federal standards for maximum contaminant levels (MCLs) in drinking water. While Massachusetts usually adopts the federal levels, the state is sometimes stricter.
In some cases when a MCL has not been set for a substance, the EPA will specify a health advisory level for that substance. It’s not a legally enforceable standard, just a guideline to protect public health. Massachusetts’ Drinking Water Program uses a similar public health guideline developed by the Office of Research and Standards. If a public water supply test reveals a substance that exceeds either a federal or state public health guideline or MCL, MassDEP requires retesting, and if the second result is still over the limit, the public must be notified, and the public water system must be brought into compliance. In addition, levels of substances that exceed public health guidelines may result in a drinking water health risk assessment, and additional actions may be taken to protect public health.
Neither the EPA nor MassDEP has set a maximum contaminant level for PFAS, although both have initiated the process. The EPA currently has a health advisory level of 70 parts per trillion for PFAS, a number that the sum of two specific substances should not exceed. MassDEP has the same public health guideline of 70 parts per trillion, but it identifies five substances that should not total more than that amount. Both agencies are still considering what the MCL will be and which substances will be included.
PFAS in the News
The New York Times published a March 14 article titled “Pentagon Pushes for Weaker Standards on Chemicals Contaminating Drinking Water.” It describes efforts by the Pentagon to avoid costly cleanup of PFAS-contaminated water in and around military bases where firefighting foam was used. According to the article, the Defense Department believes that it should not have to clean up any sites that have drinking water that contains less than 380 parts per trillion of PFAS. The EPA health advisory guideline is 70 parts per trillion for the sum of two chemicals, PFOA and PFOS. The Defense Department also reportedly wants to count those two chemicals separately, meaning that each would have to measure 380 parts per trillion before it would foot the bill for cleanup.
On March 13, the Vermont Senate unanimously passed a bill that will require all public drinking water supplies to be tested for PFAS by the end of the year, and levels must fall below the state’s health advisory guideline of 20 parts per trillion, 50 parts per trillion less than the EPA and the MassDEP guidelines. The chemicals that must total less than that limit are PFOA, PFOS, PFHxS, PFHpA, and PFNA, the same five chemicals that MassDEP uses in its current guidelines. According to the Vermont Digger, a news website, any public water supply testing over the limit will have to treat its water and provide safe water to residents until the supply tests under the limit
