Much of the groundwater on the Hanford site is still contaminated. Risks to workers and the public will be reduced by continued remediation activities.
Primary contaminants of concern include:
- Uranium
- Technetium-99
- Iodine-129
- Tritium
- Carbon tetrachloride
- Chromium
- Nitrates
- Strontium-90
All radioactive contaminants have the potential to cause cancer. Chemical contaminants can cause cancer and other health effects. At Hanford's 100 Area, along the Columbia River, strontium-90 and chromium have been a serious concern. In the past, these contaminants have entered the Columbia River at unacceptable levels.
As the diagram shows, when workers inject a phosphate mineral called "apatite" into the aquifer, it acts as a trap and separates the strontium-90 from the groundwater. This process of using apatite as a barrier prevents most of the strontium-90 from reaching the Columbia River.
Below are descriptions, health concerns, and exposure levels of radioactive isotopes and toxic chemicals found at Hanford.