PRODUCING PLUTONIUM WAS NASTY BUSINESS; for every kilogram manufactured, nearly 55,000 gallons of radioactive liquid byproducts were created during production.  An astonishing array of toxic, often carcinogenic chemicals with at least forty varieties of radioactive wastes were produced during the manufacturing process. The Hanford Nuclear Reservation includes 1,377 contaminated sites with 158 containing hazardous chemical wastes, 100 containing radioactive wastes, 996 containing mixed chemical and radioactive wastes, and 123 containing non-hazardous wastes. 
MED scientists determined that Hanford's sand and gravel substrata provided "a nearly ideal environment for ground disposal or radioactive wastes"  DuPont, the first site contractor, simply poured low-level liquid waste into open ditches throughout the desert or "mixed [it] with uncontaminated water and disposed by seepage and evaporation on the ground surface." Solid waste including contaminated clothing and equipment was buried in shallow trenches. From the time the first reactor was fired up in the mid-1940s, some 440 billion gallons of contaminated water were dumped into the ground producing over ten million tons of contaminated soil.  Work crews at Hanford continued to dump untreated waste directly into the surrounding desert as late as 1995.
More dangerous high-level wastes—those defined as containing more than 100 microcurries per milliliter of radioactivity—were pumped into a series of underground containments known as "tank farms." The tanks, built between 1942 and 1964, were constructed as single-shell units. All in all, a total of 177 high-level waste tanks were constructed throughout Hanford with the largest holding four million gallons.  When the seven reactors ran simultaneously, a total of sixty-one million gallons of the most dangerous wastes were pumped into the tanks.  Exposure to some of these contaminants would kill a person within seconds.  During the height of plutonium production nearly two-thirds of the nation's highly radioactive wastes were stored within the tanks at one time. From the mid-1950s on, leaks began to appear in tanks and processing lines. By the late 1980s at least sixty of the 177 tanks were documented as seeping toxic materials.
Explosion risks from combustible chemicals present in the tanks also posed serious issues. Accidents occurred as late as 1997, when concentrations of chemicals left in a 400-gallon stainless steel tank from a 1993 worker-training exercise exploded at the Plutonium Processing Plant in the 200 West Area. 
Hanford scientists began tracking underground movement of disposed radioactive substances as early as the mid-1940s. During the first quarter of 1957, groundwater beneath PUREX cribs (covered, open-ground waste filtration beds for the plutonium-uranium extraction facility) demonstrated concentrations of beta activity almost 100,00 times the site's allowable limit.  A 1958 report revealed the presence of gamma-emitters in water table at depths of 235-240 feet, produced by PUREX plant crib seepage. The same report additionally described how a plume of Ruthenium-106 was traveling southeastward at approximately eight miles, or 160 feet per day, from a disposal site in the 200-East Area. 
Underground plumes of radioactive waste and chemicals will continue to pose a threat to the area's groundwater system and the Columbia River for hundreds, if not thousands of years to come. Up until the late 1970s, the Department of Energy (DOE) argued it was exempt from the nation's toxic-waste crackdown and no steps were taken to curtail the contamination. With the public release of over 19,000 formally classified documents in 1986, researchers, scientists, and independent watchdog groups have been able to piece together a picture of overwhelming ecological devastation created at Hanford. Public outrage led to a multi-billion dollar "cleanup" effort that was initiated through a Tri-Party Agreement between the Environmental Protection Agency (EPA), the U.S. Department of Energy (DOE), and the Washington State Department of Ecology in 1989. With cleanup costs currently averaging of $5.1 million a day some $35 billion has already been spent as of 2002. It is estimated that it will take another $50 to $100 billion to clean up the Hanford site entirely and many years to complete it.
To curtail the spread of radioactive plumes from reaching the Columbia, ten million tons of contaminated soil is scheduled for removal to be placed at a central location within the reservation. So far, 3.3 million tons have been moved to an inland location (as of 2002 when this website was originally published).  A series of chemical "nets" are being placed across the desert to capture polluted groundwater moving towards the river. Pump-and-treat operations bring contaminated groundwater up through wells where the water is treated and injected back underground, upstream from the well. This technique has yielded mixed results—it has slowed the flow of strontium-90 to the river but less than one curie of strontium-90 from has been removed from groundwater at a cost of $4 million.  In March 0f 2002, the last section of a chemical barrier 2,300 feet long was erected 80 to 115 feet below the surface in hopes of trapping hexavalent chromium, a chemical highly poisonous to salmon and humans alike.  The chromium plume is in concentrations twenty-five times as potent as what is known to harm juvenile salmon and is suspected to have created chromosomal aberrations in wild Hanford Reach Chinook stocks resulting in sex reversal.
Other remediation efforts involve transforming some of the worst radioactive tank wastes (nearly 53 million gallons) into a glass substance resembling volcanic obsidian through a vitrification process. Construction of the vitrification plant has already begun and employs over 4,800 with completion scheduled for 2007. It should be mentioned that this process does not eliminate radioactive wastes—it simply transforms them into a more stable form. Finding permanent storage locations for radioactive wastes that emit radiation levels for hundreds, perhaps thousands of years is truly problematic. The Hanford vitrified glass was one of the many radioactive waste projects planned for storage at the controversial Yucca Mountain nuclear waste repository located 100 miles northwest of Las Vegas. Initially scheduled for completion in 2015, further funding of the repository was terminated by the Obama Administration in 2011.
Although to date over 2.5 million gallons of liquid radioactive wastes have been removed from the older single-shelled tanks and are awaiting transfer in safer double-walled units, another potentially catastrophic situation exists in the form of 2,300 tons of irradiated uranium rods representing eighty percent of the national supply. Sitting in aging concrete water pools only 400 yards from the banks of the Columbia, these immense tanks are thirty years past their intended lifespan. Contained within them is more than fifteen million gallons of contaminated water and over twenty million curies of fuel, which could ignite if the water is drained during an earthquake or possible terrorist initiated catastrophic event.  As of 2002, a nearly two billion-dollar project was underway to stabilize the rods for permanent storage.
With the facility formally decommissioned Hanford is undergoing deactivation and decontamination procedures to safely secure the old reactor buildings. This procedure, referred to as "cocooning," leaves the reactor core intact within the original building after it is encased in a concrete shell. All adjoining buildings and fuel basins are cleaned and demolished. The C Reactor was the first of the Hanford reactors to be cocooned in 1998. Nearly all of the seven additional reactors were shut down between 1964 and 1971 and have now completed the cocooning process. The N Reactor remained in operation as a dual-purpose reactor, producing power for the power grid until 1987. The B Reactor was designated as a National Historic Landmark on August 2008 by the United States Department of the Interior and is accessible during occasional guided public tours provided at the site.