Time is running out for Massachusetts' producers of low-level radioactive waste.

With just over three months left to enter an interstate pact setting up a regional waste storage facility. Bay State the agreement. Use of the regional disposal site will become crucial in 1986 when the three states that now the nation's low-level nuclear waste will be allowed to exclude the waste from their borders--an option they are expected to exercise.

If Massachusetts does not come up with an alternative arrangement by the 1986 deadline, the state's low-level radioactive waste producers primarily hospitals, research institutions and nuclear power plants will have to shut down their processes that produce the waste.

"We might have to give up treating patients, diagnosing patients, and doing research," says Parker I., Coddington, director of governmental relations for Harvard.

Tracers and other fluids used in a variety of instruments in medical research and treatment constitute low-level waste. Also, protective clothing worn by workers in commercial plants falls into this category.

The problem stems from a law Congress passed in 1980 under pressure from the states that currently receive low-level waste--South Carolina, Nevada, and Washington. The law allows states that join a regional waste disposal compact to bar non-member states from storing waste within their borders.

Massachusetts, a member of the 11-state northeastern region, has still not ratified the regional pact proposed by the Coalition of Northeastern Governors.

Lobbyists place much of the blame for the failure on the Question Three referendum passed in 1982. The law requires any prospective site for low-level waste disposal to be approved by a referendum of Massachusetts citizens in the next state-wide election.

The fact that Commonwealth voters could veto a disposal site in Massachusetts has outraged negotiators from other states in the compact, says Judy A. Shope, a specialist on radioactive waste for the League of Women Voters. Shope explains that compact members feel the law enables Massachusetts to shirk its responsibilities under the pact.

"We believe we developed a compact which is fair and workable to all," says Ronald Nelson, director of waste management in the Maryland Office of Environmental Programs. "Massachusetts could pass the compact but could not fulfill it, and this is unacceptable to us."

In order to counter problems, delegates wrote into the compact a clause which nullifies state laws inconsistent with the agreement, adds Shope.

The state must ratify the compact without amendments by a July I deadline or forfeit its right to enter the agreement. To join late, a state's entrance would have to be unanimously approved by compact members.

Because Question Three was passed by such a wide margin, legislators are reluctant to ammend or rescind it.

"I don't think this compact will pass. no matter what the deadline is," says Richard W. Smith, executive director of the Special Legislative Commission on Low Level Radioactive Waste. "As unammended, it is unacceptable," he adds.

Instead legislators are hoping delegates from states in the region meeting at MIT next week will agree to amend the compact or propose a new agreement, Smith says.

There is some chance delegates will be amenable to changes in the pact since so far it has only been accepted by four of the 11 eligible states--Connecticut. Delaware, Maryland, and New Jersey.

Ironically, if the delegates do not agree to a change, Question Three--which was designed to minimize the number of waste disposal sites in the state--may force Massachusetts to build its own storage facility in addition to the regional site