What is the state of Hanford’s groundwater today?

Some of Hanford’s groundwater is contaminated, but currently the threat to humans is very low. While about 72 square miles of Hanford’s groundwater are contaminated above drinking water standards, no one uses that water.

We expect all groundwater to be restored to the highest potential use, which is drinking water. Groundwater cleanup is underway. But in the case of some contaminants, there is no technology available to clean the water. It may remain unusable for hundreds of years.

Does Hanford's groundwater affect the Columbia River?

Some radioactive and hazardous contaminants from the 100, 200, and 300 areas enter the Columbia River today. This contamination resulted from huge amounts of waste water being discharged to cribs, ditches, and ponds during Hanford operations. In fact, so much waste water was dumped that it raised the water table about 75 feet and created above-ground lakes in the 200 Area. However, the amounts of contamination currently reaching the Columbia are very small and are immediately diluted once the groundwater enters the river.

What about in the future?

The risk from Hanford’s groundwater will increase if we do not remove all the contamination sources. In addition to contamination from cribs, ditches, and ponds, the 56 million gallons of highly toxic and radioactive waste in 177 aging underground tanks several miles from the river pose the greatest risk. The tanks will not hold their contents forever, and 67 of them are known or presumed to have leaked at least one million gallons of waste.

To stop the leaking, in 1999, we negotiated an agreement with the U.S. Department of Energy to move all the pumpable liquid out of the single-shell tanks into double-shell tanks. But a slurry of crystalized salt cake and foam remains in the tanks. Because the leaked tank waste is more concentrated than the other forms of liquid waste, it has remained in the soil of the 200 Area. However, contamination from tank waste will eventually reach the Columbia, which is why completion of the Waste Treatment Plant is crucial to protecting the river.

Find out more about Hanford's tank waste on our Tank Waste Storage and Tank Waste Disposal pages.


Primer | Groundwater Modeling


Cleaning Hanford's Groundwater | Frequently Asked Questions | Groundwater Contamination at Hanford | Groundwater Operable Unit Information | Major Contaminants | Sources of Contamination | Remediation | Groundwater Modeling | Apatite | Sitewide Groundwater and Vadose Zone Project Implementation Plan


Radiation and Toxicity Glossary | U.S. Department of Energy's Hanford Soil & Groundwater Remediation Project | Oregon Department of Energy's Hanford Groundwater Fact Sheet


Get Informed

Read Ecology's letter to USDOE about vadose zone cleanup (4/25/11)