By James Neal, Staff Writer
Enid News and Eagle
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The town of Garber is in the final stages of a plan to resolve four years’ of water quality violations with the Oklahoma Department of Environmental Quality.
The plan calls for construction of a water treatment plant to remove carbon tetrachloride and nitrates from municipal water, to be paid for with a U.S. Department of Agriculture loan and increases to city utility rates.
Testing of the town water supply has shown levels of carbon tetrachloride above maximum contaminant levels (MCL) since 2008, and also nitrate levels above acceptable limits in 2010 and again in 2012.
DEQ set MCL levels and began testing for carbon tetrachloride in 1989, and began testing for nitrates under current standards in 1992.
Garber’s current efforts to remove the contaminants from town water stem from a December 2009 Notice of Violation issued to the town by DEQ, for having carbon tetrachloride levels almost twice the MCL of five parts per billion, or 0.005 mg/L. That notice was based on testing dating back to 2008.
A separate notice was issued in January 2010 for nitrate levels above the MCL of 10 mg/L.
According to DEQ information, both of the city’s active wells tested positive for carbon tetrachloride and nitrates in 2010. The city possesses water rights to other water fields which were “taken out of service due to high carbon tetrachloride or nitrates,” according to DEQ.
When contaminant levels in the active wells began to increase, the city and DEQ entered into a long-term “consent order” to provide a permanent solution.
“DEQ continued to work with the town and due to the increasing concentration levels of both contaminants, combined with the lack of a back-up supply that met the minimum drinking water standards ... the DEQ and Garber agreed to a consent order to correct the deficiencies of the water system,” said Skylar McElhaney of the DEQ communications office.
According to DEQ, carbon tetrachloride is a chemical compound that does not occur naturally and was widely used as a dry cleaning solvent, refrigerant and in grain fumigants to preserve grain in storage.
The major sources of carbon tetrachloride in drinking water, according to DEQ, are discharge from chemical plants and other industrial activities.
Nitrates can appear in drinking water as a result of leaching from natural underground deposits and also may contaminate water as a result of runoff from fertilizer application or leaking from septic tanks or sewage systems.
Warnings concerning nitrates center on infants and pregnant women, since children less than six months old are not yet capable of processing nitrates in their digestive system. Infants who drink water with elevated nitrate levels may suffer “blue baby syndrome,” caused by depletion of oxygen in the blood.
Long-term exposure to carbon tetrachloride has been shown to cause damage to the liver, kidneys and central nervous system, and is classified by the EPA as a “probable human carcinogen,” especially related to liver cancer.
While those warnings sound ominous, government standards for water quality are based on a lifetime of exposure to any given contaminant.
“Generally, when we come up with health effects standards we’re looking at prolonged use, and for drinking water that’s considered over the course of a lifetime,” said Tim Ward, assistant director of DEQ’s water quality division.
Ward said MCL water quality standards are set by the EPA, and are based on drinking two liters of water a day over the course of a lifetime.
“With that said, you can see there is quite a bit of wiggle room in how they set the limits for those health effects,” Ward said.
There is little empirical evidence available for the effects of long-term exposure to carbon tetrachloride in drinking water.
“There aren’t any studies that will show 50 to 70 years of effects on a town from drinking water with carbon tetrachloride,” Ward said. “What we do know is this is a standard that has been set by the EPA, and all systems must comply with that standard.”
Ward said the source of Garber’s carbon tetrachloride contamination is unknown, but whatever the source, it is man-made.
“Carbon tetrachloride is man-made ... it doesn’t form in nature,” Ward said. “In some form or fashion it was placed in the environment near that well site and got into the groundwater, and nobody knows for sure how that happened.”
But it did happen, and the contamination, paired with area nitrate levels, prevent simply drilling new wells.
Garber Public Works Director Jim Whitehead said the town tested all known wells within a mile of town limits, “and they all were high in nitrates.”
“We were looking at the same situation all the way around us,” Whitehead said.
A pilot study and engineering report submitted this spring to DEQ agreed, concluding the best solution for the town was not to drill new wells, but rather to build the water treatment plant and remove both nitrates and carbon tetrachloride using water from the existing wells.
The proposed plant would enable the town to utilize not only its existing two wells, but also wells previously taken out of service due to high nitrate levels.
Whitehead said the proposed water treatment plant will cost an estimated $1.2 million, which he hopes to pay for with a loan from USDA and repay with proceeds from city utility revenue.
“We already have all the paperwork filed with USDA for the loan, and we’re just waiting to hear back from DEQ on our engineering study,” Whitehead said.
Once the engineering study is approved, Whitehead said the town will “see what kind of interest rate we can get from USDA.”
He said USDA guidelines require the loan be secured by utility revenue.
Rates certainly will have to be raised to repay the loan, but how much they will be raised will not be known until loan terms are set by USDA.
Whitehead and other town officials are hoping the USDA terms will include “forgiving” part of the loan repayment, a common practice for such loans to low-income municipalities.
“We should get some of that debt forgiven, because about 90 percent of Garber is below the poverty rate,” Whitehead said.
Whitehead hopes to have the new water treatment plant completed by next fall. It is planned to be built west of Garber Fire Department, near the intersection of Oklahoma 74 and Breckinridge Road.
“I would like to see us get this done sooner, but it just takes a while to get all the paperwork done,” Whitehead said. “The town has been working just as hard as it can to get this done, and we’ve never missed a deadline with DEQ. This has taken almost three years, not because of us, but because of the process ... because of all the paperwork required.”
Meanwhile, while the town waits for approval of its engineering plan and funding from the USDA loan, Whitehead stressed the town’s water is safe to drink.
“None of our notices has put us on bottled water or anything else,” Whitehead said. “The water is safe to drink, and it’s never been unsafe.”
However, the drinking warning due to nitrates remains in effect for infants and pregnant women.
Whitehead invited anyone with concerns or questions regarding town water or the proposed treatment plant to attend a town council meeting or call himself or interim Mayor Debbie Powell at the city office, (580) 863-2254.
