In an effort to eliminate 1,4-dioxane in county drinking water, Suffolk County Water Authority has proposed installing additional treatment systems at sites throughout the county, though costs could be high if plans see the light of day.
In a presentation to Suffolk County legislators, SWCA proposed installing 31 new advanced treatment systems at a number of sites where the levels of 1,4-dioxane are higher than the New York State proposed limit, which is 1 part per billion.
Jeffrey Szabo, SCWA chief executive officer, said the authority is continuing to develop technology that will eliminate toxic chemicals such as 1,4-dioxane.
“We have been working with the health department on our AOP (advanced oxidation process) systems and the results have been successful,” Szabo said.
A concern of 1,4-dioxane is that it can’t be removed through conventional treatment methods and involves a complex process of mixing the contaminated water with hydrogen peroxide, treated with ultraviolet light, which then gets sent to tanks filled with carbon where the rest of contaminants are filtered out. The hamlet of Central Islip currently has the sole advanced oxidation process system capable of removing 1,4-dioxane on Long Island.
The authority says that its systems can destroy 1,4-dioxane molecules to virtually undetectable levels. Szabo said there are close to 100 wells in Suffolk County that need to be treated for the toxin.
The proposed plan could take five to six years to install all 31 treatment systems, according to the authority’s chief executive officer and it would cost between $1.5 and $6 million in capital costs alone for each system.
“We are trying to get this done as quickly as possible, there are things still up in the air,” Szabo said.
The authority is waiting on the state Department of Health to adopt an official maximum contaminant level (MCL) standard. According to officials, they expect to get confirmation sometime in early 2020.
Szabo stressed that the authority and other water providers will need time to adjust to the new standards as well as to implement the new systems.
“This will take time, each system has to get approved by the department of health before it can be installed,” Szabo said.
In the case of the AOP pilot system in Central Islip, officials said it took over two years to get approval from the Department of Health.
“We want to reassure the public that we are doing everything we can,” Szabo said.
1,4-Dioxane has been designated by the U.S. Environmental Protection Agency as a likely carcinogen associated with liver and kidney damage after a lifetime of exposure to contaminated drinking water. The chemical has been found in industrial solvents, detergents, shampoos and other products.
In July, the state health department began the process of adopting the MCL of 1 part per billion. The department would become the first in the country to set a limit on 1,4-dioxane. Similarly, Gov. Andrew Cuomo (D) has planned to offer $350 million in grants for treatment.
At a forum in February, the Long Island Water Conference estimated the cost of treatment systems for close to 200 water wells contaminated by 1,4-dioxane to be at $840 million.
The authority said it is hopeful it can begin to implement the plan sometime in 2020. In addition, two additional AOP systems are currently in development for pump stations in East Farmingdale and Huntington.