A Los Angeles Superior Court judge will be asked to settle a dispute in which efforts to clean up water contamination in the San Gabriel Valley have run afoul of efforts to safeguard air quality.
The Upper San Gabriel Valley Municipal Water District, a sub-agency of the Metropolitan Water District, has sued the South Coast Air Quality Management District to block enforcement of a rule that would make water cleanup more costly.
The rule, adopted by the air quality board on Jan. 8, limits emissions from air-stripping towers, which use an aeration process to transfer volatile organic contaminants, such as trichloroethylene (TCE), from water to the air.
Attorney David Cosgrove, who represents the water district, said the required pollution controls make ground water cleanup so expensive that some water companies might be unable to afford it. Before adopting the rule, Cosgrove said, the AQMD should have evaluated its impact on ground water problems.
Cosgrove said the suit seeks to compel the AQMD to undertake a full environmental analysis, taking into account both the air quality benefits and the damage to ground water cleanup efforts.
Art Segal, AQMD air quality engineering manager, said a full environmental study was not undertaken because the rule has no adverse impact on the environment, but simply reduces a source of air pollution. Although there are only a few air-stripping towers in operation, he noted, hundreds could be built as water agencies step up their efforts to remove contaminants.
In the San Gabriel Valley alone, about 70 wells are contaminated with TCE and other industrial solvents and a number of other wells are threatened, according to the U.S. Environmental Protection Agency. Federal and state regulations set 5 parts per billion of TCE as the maximum permitted in drinking water. The only way to remove TCE and other contaminants is to extract the water and run it through some kind of treatment process. The cheapest method is aeration, a process that blasts the water with air to accelerate the natural tendency of volatile organics to evaporate.
Timothy Jochem, administrator of the operations division of Suburban Water Systems, said his company is designing two air-stripping towers to treat water at its wells in the Whittier Narrows area, near Pico Rivera. Adding equipment to filter air emissions will cost about $700,000, he said, pushing the total cost to more than $2 million.
Jochem said his company believes that before such expensive controls are required, there should be an environmental assessment to determine if the air emissions really present a health risk. The new AQMD rule requires controls on air-stripping towers that emit more than one pound of volatile organic contaminants a day.
Water officials said the rule will have little effect on air-stripping towers that are already in operation in Arcadia and Baldwin Park. Eldon Davidson, water manager for the city of Arcadia, said the ground water being treated by his city is so low in contaminants that the amounts being released into the air are below the threshold requiring pollution control measures. And Stan Yarbrough, manager of the Valley County Water District in Baldwin Park, said his agency seldom operates its aeration tower anyway because it is cheaper to use water that does not require treatment.
Niel Ziemba, who is managing the EPA's project dealing with ground water contamination in the San Gabriel Valley, said new technology is being developed that may offer an alternative to aeration towers.
The EPA has funded research at UCLA that is being implemented by the Los Angeles city Department of Water and Power in a demonstration project. Ozone and hydrogen peroxide are added to water in a process that breaks down volatile organics chemically.
Bruce Kuebler, engineer in charge of the water quality division with the Department of Water and Power, said the process creates harmless chloride ions and carbon dioxide. Nothing escapes into the air.
Kuebler said his department is seeking bids for construction of a system to use the process to treat about 2,000 gallons of water a minute. The construction cost is estimated at $1 million.
William Glaze, a UCLA professor of public health who has developed the process, said it is not cheap, nor is it a cure-all. He said the process can destroy more than 95% of the TCE in water, but more research needs to be done to test its effectiveness with other contaminants.
Glaze said the process is more expensive than aeration towers that "just throw emissions into the air." But, it may be cheaper to treat water with ozone and hydrogen peroxide than to build and operate aeration towers with emission controls, he said.
Jochem said Suburban Water Systems looked at the ozone and hydrogen peroxide process and several other technologies before deciding to design aeration towers for its wells at Whittier Narrows. He said the drawback is that those alternatives "have not been successfully applied in full-scale operations."
Until the technology is proven, he said, aeration towers seem to be the best option.
But, he said, if the towers must be built with pollution controls, the expense will drive water companies to seek cheaper alternatives, importing water or using only well water that does not require treatment. The result would be further delays in treating ground water, allowing contaminants to spread.