Area leaders are watching closely as Kern County voters prepare to consider a measure that would stop Los Angeles from dumping sewage sludge on farms in the Central Valley county.

If sludge-ban proponents succeed this spring, the Kern County initiative would have big implications for spacious Riverside County, activists and officials say, because sewer agencies in Los Angeles and Orange counties would be forced to look elsewhere to get rid of their treated human waste.

Although Riverside County is urbanizing rapidly and farm fields are being tilled under for homes on an unprecedented scale, the county still has agricultural areas that could take sludge from metropolitan Los Angeles, said Marc Miller, a Menifee activist, in an interview Tuesday.

"We are going to get a lot more of it from L.A., I guarantee it," Miller said. "Even though there's not too many fields left, the fields that are available will get more than their share."

Damian Meins, Riverside County's deputy director of environmental health, said passage of the Kern County initiative could trigger a sharp increase in proposals to truck sludge to Riverside County. Meins said there are two such proposals pending; one on the county's urbanizing west side and one far to the east in the Colorado River valley.

There is cause for concern, but not necessarily alarm, Riverside County Supervisor Bob Buster said, because in late 2004, the county passed an ordinance regulating how and where sludge may be used as fertilizer. Sludge generators must jump through hoops to get permission to bring human waste to the county, he said. And they may only ship waste that has undergone vigorous treatment.

As well, the number of candidate farms for accepting sludge is dwindling fast, Buster said.

"I would suspect that in the western county, there would only be a few keyholes they would be able to slip through," he said.

Buster said a successful Kern County campaign probably would result in Los Angeles shipping sludge to the desert areas of Riverside County and to Arizona.

That prospect gives little comfort to area activist Janine Matelko, who noted sludge already is being spread on fields in western Arizona near the Colorado River, a key water source for Southern California. She asserted that some chemicals from the sludge would spill into the river and contaminate drinking supplies.

"If it goes to Arizona, we're going to be drinking it," Matelko said. "If it comes here, we're going to be breathing it."

Sludge is the solid material left behind from sewage after water is removed and the waste is scrubbed.

Diane Gilbert, a spokeswoman for Los Angeles' Bureau of Sanitation, said the nation's second largest city generates 238,000 tons of sludge annually, more than 99 percent of which is trucked to a 4,688-acre farm the city grows alfalfa, wheat and corn on in Kern County.

The harvested crops are used to feed dairy cows, not people, she said.

Gilbert said there are few options within Los Angeles County because, since 1987, ocean disposal has been banned and landfill space is limited. Incineration is not an option, either, because that would aggravate the city's notorious smog.

Gilbert said the city is weighing a potential legal challenge to Kern County's initiative.

"Why shouldn't we be able to farm with whatever fertilizer is available to us?" she said.

However, if Kern County succeeds, she said, Los Angeles will have to look east to Riverside County and Arizona, where 30 percent and 20 percent respectively of the city's sludge was shipped last decade.

"We went into Riverside County up until 2000," Gilbert said. "We found that it was more cost effective to manage it in Kern County."

Several years ago, sludge was spread on fields throughout Riverside County, including Menifee and French Valley. That trend largely has ground to a halt, Meins said, after the county in October 2001 banned use of so-called Class B sludge, which receives minimal treatment.

In September 2004, the Board of Supervisors adopted an ordinance restricting where the more thoroughly treated Class A sludge may be spread. Under the local law, sludge is rated according to odor and its propensity to draw flies, and that rating determines how close the waste may be placed near homes and schools.

Meins said the county has yet to approve any spreading under the ordinance.

"We had some applications of Class A material that was done (early last year) by an operator without getting required permits out in the Palo Verde Valley," Meins said. "They were cited."

The operator, Seattle-based Yakima Co., has since applied for a permit and a decision is pending, he said. So is a decision on Synagro's request to spread sludge on fields in western Riverside County.

Meins said Synagro has yet to state which farms in the west county would take the sludge.

Whether a flurry of additional requests surface will hinge on what happens in Kern County, officials say.

In recent years, Kern fields have been absorbing one-third of California's sludge, most of it from Los Angeles, Orange and Ventura counties, according to Sen. Dean Florez, D-Shafter.

Florez wrote a bill last year to bar the shipping of outside-county sludge to Kern County, and it stalled in a legislative committee. He then launched a petition drive last summer to place an initiative on the county ballot.

Sandy Brockman, Kern County's chief deputy registrar of voters, said organizers gathered 24,221 signatures and they needed 15,767. After a sampling showed 83 percent of signatures were valid, the measure qualified for the June primary ballot, she said.

Brockman said the Kern County Board of Supervisors will meet Jan. 17 to decide whether to enact the measure as an ordinance or leave the matter up to voters to decide.

"I can understand Kern County's sensitivity," Buster said. "They have been getting (sludge) from every direction -- huge amounts of it."

But Buster said a ban might not survive a court challenge. He said it is the opinion of Riverside County lawyers that such a measure would be declared unconstitutional because "you can't chop things off at the county line when you're dealing with business."

Contact staff writer Dave Downey at (951) 676-4315, Ext. 2616, or ddowney@californian.com.