Arsenic widespread in well water
More than half of Maine residents get their water from wells and many of those have high arsenic levels, according to a new federal and state report.
Among Midcoast communities, Rockport and Union had the highest percentage of domestic wells that had arsenic levels greater than the level considered safe by the U.S. Environmental Protection Agency.
Those are the findings of a report issued by the U.S. Department of the Interior and the U.S. Geological Survey titled "Assessment of Arsenic Concentrations in Domestic Well Water, by Town, in Maine, 2005-09."
The study notes that the widespread occurrence of arsenic in groundwater is a well-known public health issue in Maine. Arsenic occurs naturally in bedrock in Maine and dissolves into groundwater along bedrock fractures, the study noted. Forms of arsenic were also used during the early 1900s as a crop pesticide for apples, blueberries and potatoes.
The aim of the study, according to its authors, is to educate the public about arsenic in hopes that residents will get their wells tested and then have their water supplies treated. There are various methods to treat water with high levels of arsenic.
The EPA has linked arsenic to several forms of cancer, primarily of the bladder and skin.
All public water supplies are tested for arsenic but there is no requirement for private wells to be tested.
The EPA has set the maximum safe level of arsenic in drinking water at 10 micrograms of arsenic per liter of water. A liter is slightly less than a quart. Thirty million micrograms equals an ounce.
Rockport had the 17th highest percentage of wells tested that had arsenic levels above the EPA recommended maximum. The study sampled water from 531 communities in Maine. The list of those with the highest percentage only used communities in which 20 or more wells were sampled.
Of 22 wells tested in Rockport, eight had arsenic levels exceeding the safe limit. Of those eight, four had levels greater than 50 micrograms per liter and two had levels more than 100 micrograms per liter.
Union also had one of the highest percentages of wells tested with high arsenic levels (26th highest in the state).
Of the 36 wells tested in Union, 33 percent had levels greater than the EPA limit. Three of those were in excess of 50 micrograms per liter and one had arsenic greater than 100 micrograms per liter.
The town of Manchester in Kennebec County had the highest percentage with 62 percent of the 111 wells tested with arsenic greater than the EPA limit.
The study also included a chart that listed communities and the median arsenic concentration per well tested. The median is the number where there is an equal number less than that level and more than that level.
On Matinicus Island Plantation, the median arsenic level of three wells tested was 57 micrograms per liter — the highest in Knox County.
Camden had the second highest median level in both Knox and Lincoln counties with a level of 22 micrograms per liter. Thirty-one private wells were tested in Camden.
The median level of arsenic in local communities and the number of wells tested were:
* Appleton 0.6 micrograms with 22 wells tested.
* Camden 22 micrograms, 31 wells tested.
* Cushing less than 0.5 micrograms, 20 wells tested.
* Friendship less than 0.5 micrograms, 19 wells tested
* Hope 1.6 micrograms, 22 wells.
* Isle au Haut 6.9 micrograms, 10 wells.
* Islesboro 4.0 micrograms, 10 wells.
* Jefferson 1.0 micrograms, 91 wells.
* Lincolnville 2.7 micrograms, 40 wells.
* Matinicus Island 57 micrograms, three wells.
* Monhegan Island Plantation less than 0.5 micrograms, one well.
* North Haven less than 0.5 micrograms, three wells.
* Owls Head 2.3 micrograms, 32 wells.
* Rockland 0.7 micrograms, four wells.
* Rockport 5.3 micrograms, 35 wells.
* St. George less than 0.5 micrograms, 30 wells.
* South Thomaston 1.5 micrograms, 28 wells.
* Thomaston 4.9 micrograms, 14 wells.
* Union, 2.9 micrograms, 50 wells.
* Vinalhaven 0.6 micrograms, 12 wells.
* Waldoboro 1.2 micrograms, 37 wells.
* Warren less than 0.5 micrograms, 23 wells.
* Washington less than 0.5 micrograms, 40 wells.
Amanda Gott, the office manager for Haskell's Water Treatment in Rockland, said that testing and treating arsenic in water is one of the big things the company does.
Gott noted that water must first be tested to determine what type and the level of arsenic before an effective treatment plan can be developed. She said treatment can cost as little as $1,000 or as much as several thousand dollars. She said most of the time the cost can be between $2,000 to $3,000.
She noted that Aqua Maine Water Company has a laboratory available for the tests to be done to determine which type of arsenic is in a water supply and Haskell's has its tests done at Aqua Maine.