The Army has detected unexpectedly high levels of groundwater contamination in a monitoring well mid-point between the Anniston Army Depot and Coldwater Spring - a major source of Anniston's drinking water.
The well is one mile south of the depot, in a sparsely populated area near the intersection of Knowlton Road and Jim Moore Street and south of Alabama 202.
The 205-foot well previously had tested clean, but according to data received by the Army on June 13, samples collected from the well this spring registered 150 parts per billion of trichloroetheylne (TCE).
The Army also detected 84 PPB of TCE in a well on the depot's western boundary.
TCE is a suspected carcinogen that is linked to kidney and liver damage. The Safe Drinking Water Act's maximum allowable level for TCE is 5 PPB. The maximum level detected in Coldwater Spring has not exceeded 3 PPB.
In response to the new TCE findings, the Army, the Alabama Department of Environmental Management and the Environmental Protection Agency plan to take several quick actions to protect the water supply.
In to a typed response Wednesday to questions from The Anniston Star, the Army said it will work with the agencies to:
· Increase the frequency of sampling in Coldwater Spring from quarterly to every two months.
· Revise the Army's 1996 emergency contingency plan for Coldwater Spring and private residential wells.
· Resample nine wells in the area to confirm the high result. The U.S. Environmental Protection Agency will do the sampling.
· Immediately begin the annual private/residential well-sampling event originally scheduled for August. (In the last two years, all residential wells have tested clean).
How the Army is revising its emergency plan remained unclear on Wednesday, but a state official said it will be important to ensure there is no "disruption" of water service in the Anniston area due to contamination.
Scott Hughes, an ADEM spokesman, said one possible method is to make sure water service can be switched easily from Coldwater Spring to the Anniston Water Works and Sewer Board's alternate facility at Hillabee Reservoir.
Although he said Wednesday he had not been notified of the test results, water board assistant general manager Rodney Owens said he is pleased the Army wants to increase the frequency of sampling at Coldwater Spring.
"We would certainly support that for our comfort level and everybody else's," he said.
TCE is a toxic chemical that leaked for decades from the Anniston Army Depot's industrial operation and resulted in an ongoing Superfund investigation that began 13 years ago. The TCE pollution investigation is focused on several toxic plumes migrating southeast and west in groundwater from the military installation.
High levels of TCE have been detected at the depot boundaries and in pumped water supplying Bynum's Cooper Catfish Lakes.
The Army continues to use TCE as an industrial degreaser at the depot, while it spends millions to pump and treat TCE-contaminated groundwater and to investigate the extent of the contamination.
Fractured bedrock and a lack of understanding of the aquifer have complicated the investigation. Despite thousands of samples and several dye tracer studies, it has been difficult to determine the location of the recharge zones - land areas in which water can easily infiltrate into an aquifer, officials said.
The Anniston water board recently embarked on a separate $250,000 study to try to understand the aquifer. Over the next five years, a team from the U.S. Geological Survey will run laboratory tests on chemical samples from the creek in order to learn how "old" the water that emerges at the spring is - in other words, how long it has been stored in the aquifer. The water board also hopes to learn the source of the spring and the size of the entire aquifer from the USGS laboratory tests, Owens said.
He noted that the board has a contingency plan if worse contamination is discovered in Coldwater Spring.
"TCE is a contaminant that can be treated relatively easily. The plan that we have in place to treat it above (3 PPB) would be air stripping devices," he said.
While the water board does not have air-stripping devices, it built its new Coldwater treatment plant with space to install them, he said. "As water-treatment equipment goes, it's not that expensive. It depends on the size and configuration we decided to use."
