Part 1 of 5 Parts
One of the most radioactively contaminated places in the world is the Hanford Nuclear Complex in south central Washington State. Decades of production of uranium and plutonium for the U.S. nuclear arsenal with little regard for environmental damage left a great deal of radioactive and toxic waste stored in underground tanks which are leaking. The U.S. Department of Energy has spent billions of dollars to clear up the mess but billions more are required to finish the job.
It was decided a couple of decades ago that the answer to disposing of the fifty-six million gallons of waste in the one hundred and seventy-seven underground tanks was to fuse the waste into glass logs where it would be inert and could be safely buried. Sixty of the tanks have leaked. Work on the Tank Waste Treatment and Immobilization Plant began seventeen years ago (also called the Vit Plant). So far seventeen billion dollars has been spent.
The process that the tank waste would be subjected to is referred to as vitrification. The waste pumped out of the tanks will be heated to two thousand degrees Fahrenheit and mixed with materials that are used to make glass. The molten mixture will be poured into stainless steel canisters and allowed to cool and solidify. Once the glass logs in the canisters have cooled sufficiently, they can be safely buried and will not threaten human health and the environment during the thousands of years it will take for the radioactivity to dissipate.
Vitrification technology has been used in other countries including Japan, France, Russia and the United Kingdom. In the U.S., forty million gallons of radioactive waste at the DoE Savannah River site in South Carolina has been vitrified. Unfortunately, the waste being treated at Hanford is a very complex mixture of radioactive materials and eighteen hundred other dangerous and toxic chemicals. Erik Olds is the DoE deputy project integration manager at Hanford. He said, “One of the last major challenges left, if not the last major challenge left, is to get the waste out of those tanks and turned into stable forms where we will store the waste.”
One of the reasons for the long construction phase is the fact that they began building before they understood serious problems. The contents of the tanks vary in viscosity and there are different sizes of granular materials in some of the tanks. It turned out that the system of pipes that fed the tank contents into the processing area were subjected to vibrations because of the varying physical properties of the waste stream. These vibrations caused leaks in the pipes of waste and hydrogen gas which could have resulted in explosions. Work has been stopped on the high-level waste treatment facility and the pretreatment facility since 2012.
Almost three thousand workers are attached to the Vit Plant at Hanford. This includes fifteen hundred trade workers. Hanford is ready to start the first phase of the new Vit Plant as it struggles to meet mandates imposed for the cleanup by federal courts. There are still technical and funding problems that confront the project.
Please read Part 2
Radioactive Waste 411 - Status Of Vitrification Plant At Hanford - Part 1 of 5 Parts
Part 1 of 5 Parts