The U.S. Supreme Court’s refusal to review Los Angeles’ claim that a ban on dumping sewage sludge in Kern County violates federal laws has plunged the city into distress over how to dispose of its processed human waste.

The city’s petition aimed to quash a Kern County law known as Measure E, approved in 2006 to block Southern California shipments of more than 450,000 tons a year of treated waste, called biosolids, to Green Acres, a farm the city bought in 1999 for about $15 million.

The sludge is tilled into the 4,700-acre farm’s soil to fertilize crops, including corn.

The Supreme Court declined to comment Tuesday, letting stand a previous 9th U.S. Circuit Court of Appeals decision that the city and its allies, including the Orange County Sanitation District, lacked standing to sue under federal commerce law because the case involved transfers from one portion of the state to another.

The case has been sent back to Los Angeles U.S. District Court Judge Gary A. Feess, who must decide whether to maintain jurisdiction over remaining state-level claims or allow a state court to handle them.

The petition claims Measure E is preempted by the California Integrated Waste Management Act, which requires local agencies to recycle their wastes. The petition also claims that the measure exceeds its police powers by exerting authority over another government entity’s operations.