Tests May Underestimate AF Water Contamination
By John Fleck
ALBUQUERQUE, N.M. — Tests conducted by Air Force contractors may have frequently underestimated the levels of hazardous chemicals found in Albuquerque groundwater contaminated by a Kirtland Air Force Base fuel spill, Air Force and state officials have acknowledged in documents and interviews.
The extent of the problem is unclear, but it raises questions about the accuracy of official estimates of the size of the plume and the speed with which it might be moving toward municipal drinking water wells, according to one of the leading critics of cleanup efforts.
The problem, first detected in groundwater samples collected nearly three years ago, has increased recently, according to Tom Blaine, director of the New Mexico Environment Department’s Environmental Health Division.
Tiny gas bubbles found in some water samples have the effect of masking some of the contamination, leading to samples that in lab tests show lower levels of contamination than actually present, according to a June 27 letter from Blaine to Air Force officials. Contaminants can evaporate out of the water and into the bubbles, reducing the concentration of the dangerous chemicals left behind in the water sample. The problem is especially serious when trying to measure low levels of contamination at the edge of the spreading groundwater contamination, Blaine said in an interview.
No one has been able to determine where the gas bubbles are coming from, though they most likely were created when the groundwater sampling wells were drilled or are being somehow introduced when workers are collecting water samples to be tested, according to correspondence between the Air Force and the New Mexico Environment Department about the problem.
Air Force officials, while acknowledging the problem could lead to misleading groundwater sampling results, say the issue is not serious enough to change their basic conclusions about the extent of the contamination.
Wayne Bitner, head of Kirtland’s environmental program, said the Air Force and its cleanup contractors are working to try to find and eliminate the source of the bubbles. Bitner said the number of samples taken that have no bubbles in them is nevertheless sufficient to understand the extent of the contamination.
Dave McCoy of the Albuquerque group Citizen Action, who has been monitoring the bubble problem for the past two years, disagrees, arguing that the gas bubble problem means the Air Force and state regulators may lack a clear picture of the extent of the contamination. “You’re not really aware of the full extent,” McCoy said in an interview.
Kirtland in 1999 discovered that an underground pipe in the base’s aircraft fueling area had been slowly leaking, likely for decades. Scientists have estimated that between 6 million and 24 million gallons of fuel spilled before the problem was discovered and the leak shut down. Groundwater beneath a southeast Albuquerque neighborhood a mile from the site of the initial leak is contaminated. The mess is spreading northeast toward the water utility’s nearest well. Ethylene dibromide, a possible cancer-causing chemical once used as a fuel additive, has been detected about two-thirds of a mile from the nearest drinking water well.
Scientists working for the agencies dealing with the problem have estimated it could take anywhere from 5 to 40 years for the ethylene dibromide to reach the nearest drinking water well. But McCoy, who has long complained that those estimates are based on inadequate data, cautioned that the gas bubble problem further calls the estimates into question.
The increasing concern about the gas bubble problem comes as Air Force officials are scrambling to meet cleanup deadlines agreed to last August. Although a long-term cleanup plan has not been developed, the Air Force committed at that time to taking interim steps to try to slow the spread of contamination. In June, the state rejected the Air Force’s proposed approach to halting the spread of contamination toward Albuquerque drinking water wells, and the Air Force is now working on a revised version.
Source: Military.com News
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