The city of Los Angeles, forced by the federal government to stop dumping sewage sludge into Santa Monica Bay more than two years ago, has been quietly trying to spread up to 300 tons a day of the gooey material as fertilizer over farm fields in the Antelope Valley.
In a disclosure that has raised environmental concerns, officials with the Los Angeles Bureau of Sanitation confirmed Monday that they hope to truck the sludge, more than 20% of that produced by the entire city, to five privately owned Antelope Valley farm sites totaling about 3,000 acres. The owners of the land, who have agreed to the arrangement, would receive the sludge free in return for the use of their land.
The proposal was on the agenda to be approved last week by the California Regional Water Quality Control Board meeting in Death Valley.
But action on the proposal was postponed for two months after some board members raised concerns about potential ground water contamination.
Officials from Palmdale and Lancaster--the cities closest to the proposed dumping grounds--said they were unaware of the proposal. Some of the land is only 10 miles outside the limits of the two cities.
County Supervisor Mike Antonovich, who represents the unincorporated county area where the land is located, said he also was unaware of the sludge proposal.
Los Angeles officials insist that use of treated sewage sludge as a fertilizer, a relatively new concept locally, is environmentally safe and advantageous. But they also acknowledged the practice might shock the public, and that the sludge can spill and cause odor problems.
"People don't have any problem with using manure or chicken waste as fertilizer. But when you say sewage sludge from a municipality, nobody can understand that," said Kelvin Fossett, an official in the sludge management unit of the sanitation bureau.
Sewage sludge, which contains a variety of contaminants including heavy metals, is the mud-like material that remains when waste water is treated. The city's main Hyperion Sewage Treatment Plant in Playa del Rey produces about 1,350 tons of sludge each day.
For 30 years, the city dumped all its sludge through a pipeline into Santa Monica Bay. But the federal government, citing environmental concerns, sued the city and forced a halt to that practice in late 1987. Since then, the city has increasingly tried to use the sludge as fertilizer.
The city now trucks about 600 tons of sludge a day to farms near Blythe in Riverside County and about 350 tons a day to farms near Yuma, Ariz. The Antelope Valley proposal is the first time the city has tried to use sludge as farm fertilizer in Los Angeles County.
The city hopes to shift up to 300 tons a day of the sludge now going to Blythe to the Antelope Valley. Because the Antelope Valley is only about 70 miles from Hyperion, compared to about 220 miles for Blythe, the city could save about $1 million a year in trucking costs, officials said.
The proposed Antelope Valley sludge operation would be run by Bio Gro Systems Inc., a firm that is already under contract to the city to handle the sludge trucking to Blythe. City officials said it would take about 13 trucks, operating seven days a week, to handle the load.
The proposed Antelope Valley ranches are: Bio Gro's own ranch (640 acres); the Ritter and Goode Ranch (1,280 acres); the Barnes Ranch (941 acres); the Munz Ranch (173 acres) and the Kotchian and Maricich Ranch (480 acres), a Bio Gro spokeswoman said.