The Department of Energy is aiming to spend about $1.4 billion on "supplemental technologies" for treating Hanford's radioactive tank wastes through 2028.

"Supplemental technologies" are the methods being studied to deal with Hanford tank wastes that won't be converted into glass with melters.

Right now, DOE and contractor CH2M Hill Hanford Group plan to continue studies on two such methods -- bulk vitrification and steam reforming.

The Hanford Advisory Board's tanks committee discussed Hanford's plans for supplemental technologies with DOE and state officials Thursday.

Hanford has 11 million gallons of high-level radioactive wastes and 42 million gallons of low-activity radioactive wastes in 177 underground tanks. Originally, Hanford expected to glassify the entire amount.

However, DOE and contractor Bechtel Hanford have determined that the glassification complex under construction can handle all the high-level wastes, but only 17 million to 25 million gallons of the low-activity wastes by a legal deadline of 2028.

That means Hanford has to find methods to treat the remaining 17 million to 25 million gallons of low-activity wastes by 2028 -- in ways that meet the state's regulatory approval. Another option is to add more low-activity waste melters to the present complex under construction.

One method being studied is steam reforming, which uses heat and chemicals to convert wastes into pebble-size crystals. The other method is bulk vitrification, which is pouring wastes into a huge portable container, sticking some electrodes in it, and zapping the material into glass.

CH2M Hill, which is studying the alternative technologies, calculated that using bulk vitrification for all the remaining wastes would cost $1.2 billion to $1.3 billion through 2028. CH2M Hill also calculated that steam reforming all the remaining wastes would cost $900 million to $1.3 billion through 2028.

DOE has budgeted $1.4 billion for building and operating the supplemental technologies' facilities through 2028, according to figures discussed Wednesday.

By comparison, the budget to build and crank up the glassification complex through 2011 is $5.7 billion.

The next step is for CH2M Hill to enter into contracts with some companies by Dec. 1 so those firms can build and operate test facilities to see whether steam reforming or bulk vitrification are feasible at Hanford and can treat the wastes as well as conventional glassification with melters.

DOE is supposed to have all the data from those test runs ready to send to Washington's Department of Ecology by Jan. 31, 2005. After that, state and federal experts will try to determine how to deal with the remaining 17 million to 25 million gallons of wastes, either through steam reforming, bulk vitrification, adding conventional low-activity waste melters or some combination of the three options.

Construction of any supplemental technology facilities or extra melter facilities will likely begin after 2006.