Perchlorate Is Detected In Private Wells In WestportNov 4, 2004 | Barrington Times Perchlorate has been detected in five private wells in the area around Westport High School at levels above the temporary 1.0 parts per billion set by the state. Although 20 parts per billion of perchlorate is safe for most people, high risk groups are advised against drinking or washing with more water that has more than 1 part per billion of the chemical.
The DEP tested 25 wells an area around Old County Road and Main Road. The residents on Old County Road were west of Route 88. Theresa Barao of the state Department of Environmental Protection said the highest reading was 5.62 parts per billion in one well.
The DEP is testing the private wells to try to determine the source of the perchlorate, which was detected in two high school wells last spring. The level was higher than allowable at that point in only one of the high school wells. Since then, students and staff have been drinking bottled water and using bottled water to wash.
The high-risk group includes pregnant women, children under 12 and people with untreated hypothyroidism.
Ms. Barao said the DEP was testing private wells to help determine the source of the perchlorate. Perchlorate is an organic chemical widely used as an oxidizer in solid propellants for rockets, missiles and fireworks.
"The main thing is to find the source, to look at the distribution and see how it relates to the aquifer," Ms. Barao said.
Because there is bedrock in town land in this area, the perchlorate is not moving straight down, she said.
"That's part of what we're looking at. There's bedrock there. Water in bedrock moves rather uniquely, not straight down. The geology is what will be looked at in the review, the geology and the samples. That's all taken into account."
The DEP plans to establish a definite limit for perchlorate in January 2005. Until then, it has established the 1.0 ppb limit for public buildings.
Superintendent Dr. Linda Galton said last week that in a test on Sept. 25, the perchlorate level for well #1 was 1.9 parts per billion. That makes well #1 suddenly almost twice the 1.0 level deemed safe. Last May, well #1 tested at 0.38 ppb, well below the risk level. At that time, well #2 was at 1.6 ppb. On Sept. 25, well #2 levels were 1.3 ppb.
Dr. Galton recommended against putting an expensive filter system in to treat the perchlorate until the DEP sets establishes a definite unsafe level in January 2005. Other states have set much higher acceptable levels, the superintendent said.
In the meantime, students and staff will continue to drink bottled water. The high school will use a filtering system in the cafeteria. The superintendent is still negotiating a price for the filter.
This is the first year the state environmental agency began testing for perchlorate in public buildings. The health effects of perchlorate are similar to iodine. They include impaired brain development and lower IQ as well as impairment in physical development in children. Other effects of iodine deficiency include signs and symptoms of hypothyroidism, enlargement of the thyroid gland and possibly thyroid tumors.
None of the levels of perchlorate found so far are even close to the level for the normal population.