CDM of Kansas City, Mo. and Haley & Aldrich of New York received National Ground Water Association (NGWA) Outstanding Ground Water Remediation Project Awards. The awards recognize outstanding science, engineering and/or innovation in the area of cleaning up groundwater and soil.
The $22 million CDM project competed against others that fell above the median cost for all project entries. The $2.4 million Haley & Aldrich project competed against others that fell below the median cost for all project entries.
CDM was retained by the city of Wichita to design a system to clean up groundwater contamination across a 6-mile-wide area that threatened human health, the environment and the local economy.
The resulting Gilbert Mosley Project uses 13 wells and 5.3 miles of piping to extract contaminated groundwater for treatment and “air stripper” technology to effectively treat 1.2 million gal of groundwater a day. Air strippers expose the water to air so the contaminants – in this case volatile organic compounds including tetrachloroethene, trichloroethene, dichloroethene and vinyl chloride – can escape into the air, where they are vented away.
The project also included construction of the Wichita Area Treatment, Education and Remediation Center (WATER Center). In addition to housing the water treatment equipment, the center uses the treated groundwater in fountains, aquariums, a meandering creek, an irrigation system and other water attractions. The project was initiated in 1991, and final completion was approved early this year.
“This is an extraordinary project that has deservedly earned much national recognition. Not only have more than 1 billion gal of contaminated groundwater been cleaned to date, this project has the added value of educating the public about the vital role that groundwater plays in their lives,” said NGWA’s Awards Subcommittee chair Loyd Watson.
The Haley & Aldrich project involved removing the gasoline derivatives MTBE (methyl tertiary butyl ether) and TBA (tertiary butyl alcohol) from groundwater in the area of North Hollywood, Calif. The contamination had emanated from a former gasoline station site.
In addition to the challenge of cleaning the ground water in an area that is densely populated and developed, Haley & Aldrich sought to eliminate the contamination without reducing the quantity of water in the aquifer. The site is located within the San Fernando Groundwater Basin, which is the source of the municipal and domestic water supply for the city of Glendale and the Crescenta Valley Water District.
Haley & Aldrich developed a treatment system that removed contaminated water from the aquifer, treated the water in bio-activated carbon beds with indigenous organisms and reinjected the treated groundwater back into the aquifer.
Previously, a lack of confidence in the ability to reliably treat contaminated groundwater prevented its beneficial reuse in California. The Haley & Aldrich project bucked this trend by getting approval to return treated water to the aquifer.
“This project used ingenuity to tackle a contamination problem and help people in need of drinkable groundwater. There is no higher calling than that in our industry,” Watson said.
Source: National Ground Water Association