How much and what kinds of nuclear wastes would be generated if a dormant Hanford reactor is revived by the federal government?

Opponents and proponents of restarting the Fast Flux Test Facility for up to three possible missions agree they want answers to that question, raised the latest time at a Dec. 4 Hanford Advisory Board meeting by FFTF opponents.

Now, both sides involved in the Hanford Advisory Board debate would like to know what wastes FFTF would produce and how its operation would affect Hanford's overall cleanup.

"We do need to address the issue of additional wastes. ... If a new waste stream comes from the FFTF, where will it go?" asked board member Norma Jean Germond of Oregon, representing the public at large.

The issue is supposed to be tackled by a Department of Energy environmental impact study on reviving FFTF - if Energy Secretary Bill Richardson approves. He instead could scrap the reactor.

He is due to decide within a few days.

If the study proceeds, it's uncertain what potential missions or combination of missions it will cover.

A backup or interim producer of tritium to boost the explosive power of nuclear bombs? Creating medical isotopes to diagnose and treat cancer? Making plutonium 238 to power outer space probes?

And then there are potential companion missions at the neighboring Fuels and Materials Examination Facility, built to be used with FFTF but never opened.

Would the plutonium 238 be chemically extracted at the FMEF? Would space batteries be assembled there?

The scenarios and permutations are as numerous and complicated as figuring out the National Football League's playoff picture.

About the only obvious thing is that the waste volumes and radioactivity are minor compared with existing Hanford tank wastes, 2,300 tons of spent nuclear fuel in the K Basins and other radioactive junk.

But FFTF opponents argue new radioactive wastes will be created - and that sidetracks Hanford from its main mission of cleaning itself up.

Regardless of what missions are picked, just restarting FFTF generates a basic amount of wastes, said Al Farabee, DOE's FFTF program manager.

DOE calculates FFTF's basic operation annually would generate 1,000 gallons of low-level radioactive liquid wastes, 55 cubic yards of solid low-level radioactive wastes, four cubic yards of hazardous wastes, 19 million gallons of process waste water, a smidgen of airborne radioactive emissions and conventional sewage and wastes.

Also, operating the FFTF would produce an estimated 55 to 60 spent nuclear fuel assemblies yearly.

Those assemblies first would be stored at the FFTF complex before being shipped to an outdoor pad next to central Hanford's Canister Storage Building, where the K Basins' spent fuel eventually will end up.

Later, all that fuel is supposed to go to an underground repository at Nevada's Yucca Mountain.

Meanwhile, the FFTF's low-level liquid wastes would go to a central Hanford facility that would evaporate the water, with the remaining fluids sent to the tank farms, Farabee said.

The solid low-level wastes would be buried in a standard central Hanford trench. The hazardous wastes would be shipped to an off-site disposal facility.

The airborne radioactive emissions would expose someone standing just outside the FFTF's fence to less than 1 millirem in a year, according to DOE.

That is less than what a typical Tri-Citian receives annually from dental x-rays.

Meanwhile, the FFTF's electrical equipment would generate lots of heat, which would have to be dumped through its cooling towers. Some 19 million gallons of process water cools those towers and is not exposed to any radiation.

The conventional sewage and wastes would go to a Washington Public Power Supply System sewage treatment plant or to the Richland landfill.

But there are some complicating wrinkles in all these numbers, Farabee noted.

Some calculations are 10 years old. Ways might have been found to operate FFTF with less waste.

And some unknowns still exist that an environmental impact study should track down.

Here are the extra potential wastes - beyond what is produced in the reactor's basic operation -broken down by mission:

A tritium mission.

The rodlike targets would be shipped to FFTF to be irradiated. Then, they would go to Savannah River for the tritium to be extracted.

"There would be no significant radiation dose to the public or the workers," Farabee said.

A tiny amount of tritium would end up trapped inside FFTF's cooling system.

A medical isotopes mission.

At this time, no one really knows what extra wastes would be generated by producing medical isotopes.

Farabee said the waste situation would depend on which isotopes are produced, whether they would be extracted at Hanford or elsewhere, and the timetable set for producing, extracting and shipping them.

The chemical extraction process would take place in a hot cell within a laboratory.

A plutonium 238 mission.

If FFTF only irradiates neptunium to make plutonium 238 and it then is shipped elsewhere for extraction, no extra wastes are anticipated.

But if Hanford extracts the plutonium 238, then much of the FMEF will be converted to do that.

It's uncertain how much waste would be produced by extraction.

The only figures available are from a 1988 study that looked at producing 30 kilograms a year.

Technology has changed since, Farabee noted. And today's plutonium 238 plans are looking at making only 2 to 5 kilograms a year.

Another wrinkle is whether Hanford is picked to assemble the space batteries that would use the plutonium 238 as their power source. Hanford is one of six sites being considered to make Radioisotope Thermoelectric Generators.

Figures from 1988 indicate such a project would produce 50 gallons of low-level radioactive wastes and about 50 cubic feet of low-level solid radioactive wastes a year.

The liquid wastes would go to a central Hanford evaporator to remove the water. The solid wastes likely would be buried in central Hanford.

Farabee cautioned that those figures need to be restudied and updated.