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Orange County

Sludge Options Go Down Drain

Waste: The Orange County Sanitation District is finding fewer takers for the leftover gunk from sewage treatment, and cleaning it will be costly.

November 09, 2001|SEEMA MEHTA | TIMES STAFF WRITER

As farming counties start shutting the doors to Orange County's exported sewage sludge, local planners are counting on making the solid gunk from the county's waste water cleaner--a process expected to carry an eight-figure price tag.

But just in case, they're keeping open the option of just shipping the stuff to Arizona.

At a meeting this week, Orange County Sanitation District officials laid out their woeful situation to a district committee: Riverside County stopped taking the county's sludge last summer. Two counties in the Central Valley will stop in 2003. Cleaning up the sludge to the point where those three counties would resume or continue accepting it will cost tens of millions of dollars. But so would trucking it all the way to another state.

"It's not an option not to take some kind of action," district spokeswoman Lisa Lawson said. "We have to find other places that will accept [our sludge] or look at options for treating it to . . . a higher level."

The district treats and disposes of waste water from the toilets, sinks, showers and dishwashers of more than 2 million residents of northern and central Orange County. Its plants in Fountain Valley and Huntington Beach separate the liquid from the solids, or sludge. The sludge then is treated to remove some bacteria, viruses and volatile organic compounds. More water is removed. At this point it's considered Class B biosolid, which means it still contains many pathogens.

The resulting 200,000 wet tons a year, 541 wet tons a day, of coal-black gunk is trucked to farms. (A wet ton is about 500 pounds.) The Sanitation District relies on the agriculture industry to use it to fertilize nonfood crops such as alfalfa and cotton.

None of the sludge is used in Orange County because there is little farmland. Most sanitation agencies, including those in Los Angeles County, have relied on farmers in Kern County and the rest of the Central Valley.

Orange County officials had also relied heavily on Riverside County, sending nearly half their sludge there. But last summer, Riverside officials voted to ban Class B sludge use for health and aesthetic reasons--it has a foul odor--making it one of at least 19 counties in the state to restrict or ban Southern California's mountainous stockpile of human waste.

The local district is not alone in scrambling to find solutions. The city of Los Angeles is seeking federal permission to inject treated sludge into a nearly depleted oil and gas reservoir a mile underground at Terminal Island in Los Angeles Harbor.

South Orange County, which is covered by a different agency, also is studying its sludge management but is not in the same bind as the Orange County Sanitation District--primarily because it's much smaller and produces much less waste.

The Orange County Sanitation District still sends sludge to San Diego, Kern and Kings counties.

But Kings and Kern have passed ordinances banning the import of Class B sludge starting in 2003, a deadline that has the Sanitation District scrambling to find alternatives in time. And San Diego County says it has too little farmland to take any more than it already does.

As a result, district officials are moving toward treating the sludge so that it qualifies as Class A by removing more disease-causing bacteria, viruses and toxic metals. The more thorough treatment is expensive and will result in rate increases for customers, though Lawson said the amount will be unknown until next summer.

That extra treatment can be done by composting, chemical stabilization or heat-drying. The local district is looking at the first two, because heat-drying is expensive and the resulting ash would create another disposal problem.

Chemical treatment involves adding alkaline chemicals and acid to the sludge, creating high temperatures and acidity that kills pathogens.

In August, the district entered into a five-year agreement with California Soil Products in Los Angeles to treat at least 100 wet tons per day using chemical stabilization. Annual costs will be no more than $2.6 million, but that would take care of less than a fifth of the district's output.

Another proposal discussed Wednesday evening involves buying land in Colton so that Inland Composting and Organic Recycling could turn the sludge into compost, which is still acceptable to many counties.

Land acquisition and other capital costs would be between $43 million and $68 million. In addition, it would cost $22 per wet ton to treat the sludge. The district expects to send 300 wet tons there a day starting in mid-2003. That would cost about $2.4 million a year and treat close to 60% of the sludge. The district seeks to keep costs down by charging cities a premium of about $40 per wet ton.

In early December, the Operations, Maintenance and Technical Services Committee will vote on the proposal and forward a recommendation to the district's board of directors for a Dec. 19 vote.

Meanwhile, the district is paying $600 a month to reserve space at an Arizona landfill in case there aren't enough places to send the sludge by 2003. Because of the high cost--$8.2 million a year to take less than 80% of the sludge--this is a backup option to be used only in case of emergency.

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