Labeling cocaine a hazardous material and an environmental toxin, state health authorities have ordered that it no longer be incinerated, leaving bundles seized from dealers and users to pile up in police warehouses and evidence lockers throughout Southern California.

But not everywhere. While some law enforcement agencies have begun stockpiling the drug while waiting to find a new way to destroy it, officials at other agencies said they were not told of the new state rule and continue to ship seized cocaine to incinerators in Riverside and San Bernardino counties.

The Los Angeles Police Department still goes for the slow burn, a spokesman said. The Los Angeles County Sheriff's Department is stockpiling, a spokesman there said.

Though the state rule is almost two years old, the first many police agencies heard of it was when contacted last week by reporters.

"I think people were kind of shocked," said Maureen Haacker, a Santa Ana police spokeswoman. "We had not heard anything like that. We are still (using incineration)."

Cornelius Dougherty, a U.S. Drug Enforcement Administration spokesman in Washington, said he had not heard of any other state with a rule like California's.

"What it all means and all that, we haven't had a chance to analyze here at headquarters," he said.

Incinerating cocaine has been banned throughout California since an Oct. 5, 1989, ruling--by what was then called the state Department of Health Services--labeled the drug as highly toxic, said Bob Borzelleri, spokesman for the state Department of Toxic Substance Control. The ruling does not ban the incineration of other drugs.

The ruling stemmed from a request by a small, unnamed police department that asked how to dispose of cocaine it had seized.

As word of the new rule began to circulate, law enforcement officials expressed confusion and frustration--and uncertainty over how to dispose of the drug.

"In the worst-case scenario, we could sit on it for a year before we're bulging at the seams," said Lt. Skip Murphy of the San Diego County Sheriff's Department, which disposes of cocaine from seven local agencies.

New disposal methods are likely to be expensive, police officials said. A broad reading of the state standard could make disposal of other drugs--heroin, crystal methamphetamine and marijuana--equally difficult, they said.

Many were critical of the rule.