State health officials were ordered yesterday not to remove flood debris from dioxin-plagued Times Beach to another county, despite an earlier agreement with the federal government.

An order signed by Gov. Christopher Bond broke an agreement that had been reached by state and federal officials over disposal of the silt-covered waste. Some 800 truckloads of the debris were to be taken to a hazardous waste site in nearby Warren County.

If the governor had not acted, Warren County prosecuting attorney Tim Joyce said he would have gone to court. "People here simply don't want Times Beach's contamination in our county," said Joyce.

He said a court order would not be sought in the wake of the governor's action. But "I can assure you that I'll file for it the day they try to move it here," Joyce added.

Resistance to the move surfaced Wednesday after it was announced that the debris would be buried at Bob's Home Service, Missouri's only licensed hazardous waste dump.

The federal government has agreed to pick up 75 percent of the tab for the transfer of the flood debris, with the state paying 25 percent.

Also yesterday, President Reagan, responding to a request from Bond, agreed to set up a task force to study ways to streamline the federal government's response to the dioxin problems in Times Beach.

Bond said the newly formed task force would meet this morning.

In asking for the group, Bond said various federal agencies have been duplicating each other's efforts in Times Beach.

Tests conducted before last month's floods were invalidated after flood water swamped the entire town. Those tests showed dioxin levels up to 100 times higher than at other sites where cleanups of the toxic chemical have been ordered. Dioxin, a waste byproduct of herbicides and other chemicals, has been called one of the most deadly synthetic chemicals known to man.

Authorities say it is known to cause cancer, liver failure, birth defects and other problems among laboratory animals.

The Times Beach contamination stemmed from the spraying of unpaved roads with waste oil to control dust in the early 1970s.