WRPS is committed to the timely and transparent release of information related to chemical vapors in the Hanford tank farms. This website seeks to provide data, news and background information so interested parties can have an informed dialogue on this important issue. AOP-015 Event Investigation Reports are available here and C-67 Event Investigation Reports are available here and are published in accordance with the Settlement Agreement (full) (Settlement agreement with modifications 02/01/2023) after the reports have been completed and approved for publishing.


What are

Hanford Vapors?

Hanford tank vapors are complex. Learn more about what chemicals in the tanks, the types of chemicals, Occupational Exposure Limits (OELs), and various vapors sources.

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How we

Protect Workers

Learn more about the vapors management strategy, industrial hygiene (IH) sampling and monitoring, the Tank Vapors Assessment Team (TVAT) Implementation Plan and other independent assessments.

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A respirator is a device worn by workers to protect against harmful dust, fumes, vapors or gases. Air-purifying respirators (APRs) use a filter cartridge to clean the air before it enters the respiratory tract.

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We are building the

Farm of the Future

Washington River Protection Solutions has implemented a proactive management approach to chemical vapors exposure. This includes:

  • Ensuring farm boundaries are protective and safe
  • Providing centralized command and control
  • Implementing a comprehensive plan inside/outside farm boundary
  • Establishing rigorous source identification and effective controls

The Breakdown


Hanford has 177 tanks: 149 single-shell and 28 newer double-shell.


Hanford’s tanks contain 56 million gallons of high-level radioactive and chemical wastes.


There are 1,800 different chemicals in Hanford’s tank waste.


61 of those chemicals pose a potential health concern to Hanford workers.



What is WRPS doing to protect workers?

Washington River Protection Solutions has continued to improve its tank farm industrial hygiene program with additional staff, new equipment, updated procedures, and improved worker training. [...]Read More


What is an AOP-015?

Chemicals are routinely monitored in the tank farms. When a Personal Ammonia Monitor alarm occurs the TF-AOP-015 procedure is initiated. [...] Read More

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