Hanford Completes the Grouting of Plutonium Uranium Extraction Facility Tunnel 2
Our team at the Hanford Site recently marked a huge milestone – and minimized potential risks to human and environmental health. Read about their latest accomplishment in this article.
On April 26, CH2M HILL Plateau Remediation Company (CHPRC), wholly owned by Jacobs, finished filling the Plutonium Uranium Extraction (PUREX) Tunnel 2 at the Hanford Site, in Washington State, with engineered grout. This marks a huge milestone for the site and the workers as it removes the potential for future tunnel collapse and possible release of radioactive materials.
The decision to grout Tunnel 2 was made after the partial collapse of an adjacent waste storage tunnel, known as Tunnel 1, in May 2017 caused an emergency response and shut down work at the Hanford Site for two days. An estimated 6,000 cubic yards of grout were needed to fill Tunnel 1, requiring about 650 truckloads to fill the nearly 360-foot long tunnel.
The Department of Energy recognized CHPRC with the Voluntary Protection Program Innovation Award for stabilizing Tunnel 1. “DOE is proud to recognize CHPRC employees for their innovation and commitment in the response to the PUREX tunnel emergency,” said Doug Shoop, manager of the DOE Richland Operations Office. “Their work in filling the tunnel with grout has eliminated the risk of further collapse, and the lessons learned will aid in stabilizing a second waste storage tunnel with grout.”
An engineering evaluation of Tunnel 2 showed it also was at great risk of collapse. Grouting efforts on the tunnel began in October 2018 and crews placed the last truckload on April 18. The tunnel contains 28 railcars with containment processing equipment and materials generated during the Hanford Site’s weapons production era. Grouting was determined as the best approach for this project by experts due to the maximum level of stability and protection it will provide to the tunnel. Tunnel 2 is considerably larger than Tunnel 1 at nearly 1,700 feet long, is constructed of steel and concrete, and was used between 1964 and 1996.
Hanford workers did an outstanding job working safely during the months they were stabilizing the tunnel, despite working in some of the most challenging winter weather conditions in 100 years.
“The safe completion of this important work is a testament to the dedication of the workers in the field, support staff across our company and cooperation of all the site contractors,” said Ty Blackford, CHPRC president and chief executive officer.“It took a lot of preparation and day-to-day attention in a hazardous environment to ensure we could make, move and place thousands of trucks of grout safely while assuring the potential for a radiological release was minimized.”
The Hanford Site continues to prove their commitment to protecting the environment, the community and their workers through their actions every single day – and since 2008, we’ve managed the environmental cleanup of the Central Plateau at the Hanford Site. Read more about our work on one of the largest environmental protection programs in the world, including construction, expansion and operation of pump and treatment facilities to treat contaminated groundwater and support the overall mission of protecting the river.