When Fantastic Caverns went public with concerns about chemical pollution from a Springfield industrial site, property owners with wells nearby flooded state regulators with requests for free water well testing.
The first 35 free water well samples have been tested, and DNR reports that five of those had the chemical, though at levels below the EPA’s maximum allowable limit for human exposure in drinking water.
"The department is mailing sampling results letters for the first 35 wells sampled to property owners this week," said Valerie Wilder, DNR Superfund section chief.
DNR so far has collected samples from 145 private drinking water wells; seven wells were sampled on Nov. 15; 28 wells on Nov. 19; and 110 wells Dec. 3-4.
"The Department will be resampling any well with a detection of TCE in January to verify the results," Quinn added.
Before these latest water well tests, DNR previously tested more than 70 private drinking water wells in the area and found 13 with detectable levels of TCE, including one well that showed TCE slightly above the EPA’s Maximum Contaminant Level of five parts per billion.
According to DNR, a public well system known as the County Squire Village well (a public well serving 189 people located 1.5 miles east of the Litton site) had a detection of TCE in 2010 of 0.5 parts per billion TCE, and then again in 2016 of 0.71 parts per billion.
Both levels are below EPA’s limit for drinking water and there has been no treatment system added to remove the contaminant.
However, Fantastic Caverns has begun drilling a series of vent holes near the show cave in hopes of catching TCE vapors before they reach the public areas.
Quinn, at DNR, said carbon filtration systems and reverse osmosis systems are effective at removing volatile organic compounds (VOCs), including TCE, from drinking water.