Officials with the San Gabriel Basin Water Quality Authority (SGBWQA) and the U.S. Environmental Protection Agency (EPA) gathered in the City of Industry last week to announce and celebrate the start of construction of a groundwater treatment system in Puente Valley as part of ongoing cleanup at the San Gabriel Valley Superfund Site. The new $40 million treatment system will capture and remove volatile organic compounds (VOCs), 1,4 dioxane, perchlorate, and hexavalent chromium from groundwater. Existing groundwater contamination is the result of decades of improper handling and disposal practices by individual facilities that released industrial solvents into the soil and groundwater.
“This new facility in the City of Industry is a milestone for the San Gabriel Basin and the Water Quality Authority,” said SGBWQA Board Chairman Jorge Marquez. “It represents the 32nd water treatment facility built in the San Gabriel Valley and it is the first to use reverse osmosis in the treatment process.”
The EPA established the Puente Valley Operable Unit (PVOU) as part of the San Gabriel Valley Superfund Sites in 1984. Groundwater monitoring had revealed significant volatile organic compound (VOC) contamination in groundwater within the southeastern portion of the San Gabriel Valley. An original cleanup plan was prepared in 1998 and updated in 2005 addressing an approximately 5-square mile wide plume of contaminated groundwater that extended beneath the City of Industry, City of La Puente, and portions of unincorporated areas of Los Angeles County.
The EPA will oversee the installation of two miles of underground pipeline and the construction a groundwater treatment facility by Northrop Grumman Systems Corporation. When completed, the facility will extract contaminated water from underground and send it to the new treatment plant. Over two million gallons of groundwater will be treated at the new facility daily and meet state and federal drinking water standards.
The cleanup plan calls for three separate groundwater cleanup systems in the PVOU to remove and treat contaminants from different groundwater areas. Each system will consist of its own groundwater extraction wells, pipelines, and treatment plant. Whereas the first part of the system in now under construction and due for completion in 2020 the other two groundwater systems will address shallow groundwater and are expected to start construction by 2020. Once construction on the new treatment system is complete, EPA will oversee testing of the water before the California Division of Drinking Water issues a permit to La Puente Valley County Water District to operate the treatment facility and distribute the water to local users.
“Today we celebrate a big milestone at this site,” said EPA Pacific Southwest Superfund Assistant Director Dana Barton. “The construction of this new advanced treatment facility will protect the existing groundwater supply and provide a reliable source of potable water for residents and businesses.”