by Beth Geiger
Our reporter visits the world’s biggest environmental cleanup.
I stood on the brink of a vast landfill. Below me, workers piled soil onto sealed containers. Trucks labeled Caution: radioactive material” rumbled by. In the distance, windowless buildings loomed above the bleak landscape.
It looked like the set for a movie about a nuclear wasteland. But it was real-the Hanford Site in eastern Washington state. It’s the largest environmental cleanup operation on Earth. The U.S. Department of Energy (DOE) is now mopping it up.
Hanford was once an enormous industrial complex covering almost 1,550 square kilometers (600 square miles). It included factories, nuclear reactors, and hundreds of other buildings. Its main product was plutonium, a silver-white metallic element that’s used to fuel nuclear bombs. The nuclear bomb that the United States dropped on Nagasaki, Japan, on Aug. 9, 1945, contained plutonium made at Hanford.
This is one of Hanford’s defunct nuclear reactors. In the reactors, controlled nuclear reactions turned uranium fuel into small amounts of plutonium for use in nuclear bombs. Beth Geiger
Hanford stopped making plutonium in the 1980s. By then, the site was a huge mess. Billions of gallons of contaminated water had been spilled on the ground. Contaminated equipment lay buried all over the place. And underground tanks were leaking chemical and radioactive waste into the nearby Columbia River. Radioactive materials contain unstable atoms that emit high-energy rays. Exposure to those rays is extremely hazardous.
“It’s hard to get your mind around how big Hanford is,” Cameron Hardy of the DOE told me as we drove through the site. I saw what he meant. We had already driven past miles of sagebrush, metal fences, and faceless concrete buildings, and some of Hanford’s nine nuclear reactors were just coming into view.
Finally, we made our first stop, at a groundwater treatment plant. During Hanford’s heyday, water used to cool the nuclear reactors and process plutonium was simply dumped on the ground. Some of it seeped into the groundwater, which flows into the Columbia River. The DOE’s goal is to reclaim the water before it reaches the river.
One contaminant in Hanford’s groundwater is chromium 6, a toxic chemical. Chromium 6 is very mobile, or readily transported, in groundwater. Another contaminant is strontium-90, which is radioactive.
Cleaning up the groundwater involves pumping it to the surface. The chromium 6 is extracted and converted to chromium 3, which is safer and less mobile. The strontium-90 is absorbed by a mineral called apatite, which is injected underground. Within two years, the DOE will be pumping and treating 16,280 liters (4,300 gallons) of groundwater-the equivalent of 85 bathtubs’ worth of water-every minute.
Hanford also has 200 million liters (53 million gallons) of toxic liquid on its grounds. To immobilize that stew, the DOE is building a vitrification plant the size of six shopping malls. Vitrification is the process of making glass. In the Hanford plant, explains DOE glass scientist Albert Kruger, the toxic waste will be heated to 1,150 degrees Celsius (2,100 degrees Fahrenheit). As the hot waste cools, it becomes glass, which will be sealed in steel canisters and buried underground.
When completed, Hanford’s vitrification plant will be the world’s largest chemical processing facility.
The first glass won’t roll out until 2018. Even then, it will still take 40 years to treat all the liquid waste.
The cleanup doesn’t stop there. Hanford is also a gargantuan grab bag of solid waste-hundreds of old buildings plus scores of underground burial sites. The burial sites contain tons of contaminated equipment, tools, partly decayed drums, soil, and train cars.
The nuclear reactors are now being cocooned. Everything but their radioactive cores is being destroyed. The cores will be sealed for perhaps 75 years, or “until enough radioactive decay has gone on,” explains DOE environmental scientist Nick Ceto. Decay is the slow breakdown of radioactive substances into more stable elements. Other buildings are being dismantled.
The burial grounds are a deeper problem. Hundreds are left to excavate and sort through. It’s a slow process, says Hardy. At every step, workers must be protected from radiation, chemical contamination, and fire. “Some of the waste will spontaneously catch fire if it’s exposed to air,” he says.
Where does most of the waste go? In a landfill the size of 35 football fields. The landfill is not just a big hole in the ground. At least 10 layers of material will keep it leak-proof for thousands of years. From the landfill’s edge, I cautiously peered down seven stories to the bottom.
AP Images. Hanford Site workers wear suits to protect themselves against hazardous vapors.
As I left the Hanford Site, my head was reeling-and not from radiation. I was thinking about the vast operation, which will take at least 50 more years and consume billions of dollars.
Yet everybody I talked to agreed that cleaning up Hanford must be done. Otherwise, more contaminants will reach the Columbia River, says Ceto. People might stumble across dangerous radioactive waste. Wildlife could spread the contamination. “We’re trying to protect the whole food chain,” he says. Clearly, we’re in this mess for the long haul.
breakdown break ·down
- a failure to operate.
The breakdown of the bus made the children late for school.
- a serious failure of a person’s mind or body.
After her breakdown, she was in the hospital for three weeks.
- a malfunction, as of a machine.
- a physical, emotional, or mental collapse.
- an analysis or reduction into smaller units.
Give me the breakdown of our sales this year.
These are some examples of how the word or forms of the word are used:
- The process of weathering (the breakdown of rocks by chemical, mechanical, and organic processes) has worn down softer rock, exposing the hardier metals, such as gold, tin, and coltan.
- Decay is the slow breakdown of radioactive substances into more stable elements.
- Weathering is the gradual breakdown of rocks.
- Stuttering is thought to be a neurological disorder–a breakdown in the brain’s ability to coordinate speech.
excavate ex ·ca ·vate
- to dig up and remove material from.
The bulldozer excavated an area for the foundation of the new house.
- to make a hole or cavity in by digging or scooping out the interior portion.
- to form (a hole, tunnel, or the like) by digging out material.
- to expose by digging away overlying material; unearth.
- to expose an archaeological site.
- to engage in digging out material or hollowing out something.
excavar: The Spanish word excavar means excavate.
These are some examples of how the word or forms of the word are used:
- Scientists will return with shovels to excavate the mammoth bones.
- The burial grounds are a deeper problem. Hundreds are left to excavate and sort through.
- Many archaeologists do excavate in such locations. The one characteristic that unifies all archaeologists, however, is the study of human development through artifacts-material remains.
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