Thursday, August 11, 2011

LANL TRU Waste Permit Modification Request

The Los Alamos National Laboratory TRansUranic (TRU) Waste Permit Modification Request Public Meeting was held on 10 Aug., 2011, between 5:30 - 7:30 PM,  at Fuller Lodge in Los Alamos, NM. The intent of this meeting is to discuss a Permit Modification Request (PMR) being made to the New Mexico Environment Dept/ 's Hazardous Waste Bureau, which issued the original Resource Conservation and Recovery Act (RCRA) Hazardous Waste Facility Permit last year.

There were ~35 people in attendance at the PMR meeting; of these, ~25 were from LANL, 1 was from NMED, and ~10 were from the general public. Among the members of the general public were Joanie Arends (Concerned Citizens for Nuclear Safety), Scott and Susan Kovacs (Nuclear Watch of New Mexico), and myself. The meeting was facilitated by Bruce MacAllister, and there were 3 LANL presenters: Matt Nuckols (civil engineer), Greg Juerling (project manager), and Gian Bacigalupa (RCRA permitting process expert).

The PMR will be for one new LANL hazardous waste facility, in which up to 105,875 gallons of TRU  waste will be characterized and stored, while awaiting shipment to the Waste Isolation Pilot Project (WIPP) site in Carlsbad, NM. The new facility will be located at TA-63. The present RCRA Permit allows for the characterization and storage of up to 4.5 million gallons of TRU waste, now being stored at TA-54.

As planned, the new facility at TA-63 will be adjacent to the plutonium facility at TA-55; this is the source of the majority of the TRU waste being generated now, and will continue to be so into the foreseeable future. Currently, the 2nd largest source of TRU waste is the old CMR building. If the CMRR-NF is eventually built, replacing CMR, it will probably be sited next to TA-55 and is expected to generate as much TRU waste as CMR. The 3rd largest amount of TRU waste now comes from the Radioactive Liquid Waste Treatment Facility, which is also expected to continue to operate into the foreseeable future.

Each of the TRU waste generator sites (TA-55, CMR, and RLWTF) will package its own waste into numbered 55 gallon steel drums, the contents of each drum will be recorded and the drums will be sealed. The sealed drums will be transferred to TA-63 where their contents will be "characterized", and the drums stored while awaiting shipment to WIPP.

Characterization of the contents of each drum will consist of: radiography of the sealed drum, in order to ensure the absence of certain prohibited items (no liquids are being accepted at WIPP); measurement of the intensity of radiation (primarily neutrons and gammas) emanating from the sealed drum, in order to ensure that the dose rate, at the container wall, is less than 200 mrem/hr (which is the maximum allowed dose rate for so-called contact-handled TRU waste); and anaysis of the gases emanating from the HEPA filter terminating the vent attached to each sealed container, in order to ensure the absence of certain radioactive, poisonousness and/or corrosive gases.

The new facility will store TRU waste containers in 6 buildings, designed with fire suppresant systems, located at TA-63. This will be an improvement over the current situation at TA-54, where containers are stored on concrete pads covered by fabric domes. These domes are vulnerable to fire. It was only due to aggressive fire-fighting and to much good luck that these domes didn't burn during the recent Las Conchas wildfire (which.burned more than 244 square miles over 36 days in the mountains surrounding Los Alamos.) Ten years ago, the Cerro Grande wildfire also very seriously threatened LANL buildings.

During the PMR Meeting, it was stated by LANL staff that if any of the proposed TA-63 buildings were to burn in an uncontrolled manner, due to accident or wildfire, then TRU waste containers being held in storage could rupture, due to rapid expansion of the trapped gases inside the containers. A worst case scenario of this sort had been modeled, and it was thought that no more than ~5 rem would be absorbed by workers during such a catastrophic event. The annual dose allowed by the DOE for an employee working around radioactive materials is ~1 rem/year. Even so, a person or persons who absorbed a dose of ~1 rem within a period of minutes or hours would probably not experience any symptoms of radiation sickness. But, whether a maximum dose of 5 rem  is realistic is another question. After all, the new facility will be permitted for 105,875 gallons (~425 m**3) of TRU waste which, if one accepts the DOE's estimate of the average activity of contact handled TRU waste as being 47 Ci/m**3, implies a total activity of ~19,900 Ci (mostly isotopes of Pu.) If this material should all be released into the facility's buildings, then this would be more than enough to compromise the health of anyone unfortunate enough to be present, even briefly, in those areas.

As was pointed out by Joanie Arends, DOE plans to close the WIPP site in ~2030. After that, and absent any new plans for waste disposition, TRU waste generated at LANL will stay at LANL.

DOE anticipates that by ~2030 WIPP will contain a total of ~9 million Curies (Ci) of TRU waste. This waste must "remain isolated from the biosphere" for a time much greater than 24 thousand years; i.e., the half-life of Pu239, the radionuclide making up ~10% of TRU waste, and the one with the longest half-life. By contrast, most of the TRU waste has a half-life of less than 100 years.

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