New Process to Cleanse Wells : Firm to Design Pilot Water Plant

Los Angeles water officials Thursday hired a consulting firm to design a pilot treatment plant in North Hollywood that will use a new process to cleanse San Fernando Valley water-supply wells of industrial solvents.

James M. Montgomery Consulting Engineers was awarded a contract of up to $423,200 to conduct feasibility and environmental studies and to design the North Hollywood demonstration plant. The plant will use hydrogen peroxide and ozone to break down the solvents’ chemicals into harmless byproducts.

The contract was approved by the Los Angeles Board of Water and Power Commissioners, which oversees the Department of Water and Power.

Officials see the new process as an alternative to two treatment methods that are proven but which create hazardous waste. One method, aeration, rids water of solvents through evaporation, but vapors are trapped in filters that must be handled as hazardous waste. The other method, carbon filtering of water, also creates hazardous waste in the form of spent filters.

Besides eliminating the waste-disposal problem, the experimental method may “do a better job at a lower cost in removing these contaminants from the water,” said Henry Venegas, assistant division chief for water engineering and design at the DWP.

Venegas said the pilot plant, which will treat 2,000 gallons of water a minute, may be built next to a city well near the intersection of Vanowen Street and Beck Avenue. He said that environmental and design studies could take 4 to 6 months and that the plant, which could cost $500,000 to $1.5 million to build, could be operating in a year.

The new process is designed to break down the trace chemicals, principally trichloroethylene (TCE) and perchloroethylene (PCE), that have polluted public water-supply wells from North Hollywood to Glendale. The ozone used in the process is a confined, highly concentrated form of the gas, which is a primary component of Los Angeles smog.

Experts believe the process is the most promising of four experimental treatments recently tested by UCLA researchers under contract with the DWP and the federal Environmental Protection Agency.

Valley well fields operated by Los Angeles, Burbank, Glendale and the Crescenta Valley County Water District have been designated for cleanup under the federal Superfund toxic-sites program.

More than 2 dozen wells have been shut down because of pollution. Water from less polluted wells is being blended with fresh supplies.