The Weldon Spring Site Waterline Replacement Project at the U.S. Department of Energy (DOE) Office of Legacy Management’s (LM) Weldon Spring Site, Missouri, began in early 2020 when site engineers started planning to right-size a remediation-era waterline supplying a storage building and office trailer on site. This type of preventative maintenance is common at LM sites, where site managers are tasked with continually evaluating how to best apply taxpayer funds to long-term stewardship.

The original waterline dated back to the remediation era in the 1990s when the Weldon Spring Site Remedial Action Project was well underway. Remedial activities concluded in 2001 and since then several of the buildings and fire hydrants were deemed unnecessary for future use and were removed.

The Weldon Spring Site had an oversized waterline with a capacity that exceeded the site’s current usage and inhibited the lines from flushing properly. Perched water was also seeping into the water metering vault, which was not originally designed to have a sump pump. Removing the excess perched water was a labor-intensive task.

In 2018 LM and LM Strategic Partner (LMSP) staff began the cross-discipline effort of planning and designing the water line replacement and water vault removal. Experts from environmental compliance, construction management, oversight, engineering, and procurement collaborated to determine the most efficient design and path forward to meet the site’s current water needs.

The blue magnetic locator tape seen here below fill and water will allow future detection once the trench is fully filled and covered.

The blue magnetic locator tape seen here below fill and water will allow future detection once the trench is fully filled and covered. 

This kind of complex work on LM sites is managed through an integrated work control process, which ensures working toward clearly established objectives, open and frequent communication, and adherence to scope, scheduling, and funding. The waterline replacement project also required site staff to closely coordinate with the local water company, so that the work process and site safety protocol were understood by all parties.

During the project, the team also removed another nearby legacy water vault that was no longer needed.  To address the site’s current water usage and prevent any potential flooding, the team designed a smaller vault.

The legacy water vaults were considered confined spaces and their removal makes the site safer. Confined spaces pose a risk to workers and the public because someone could become trapped in them without proper safety protocols in place. Removing the legacy water vaults and replacing them with smaller vaults enabled LM to eliminate safety hazards, while increasing the sites efficient water usage.

A pipeline trench, identified as the South Area, dug for the waterline replacement project.

A pipeline trench, identified as the South Area, dug for the waterline replacement project.

The Waterline Replacement Project began with procurement in the summer of 2020 and the field work began in the late summer during the COVID-19 pandemic. The unprecedented safety concern of the pandemic required the team to incorporate LM’s COVID-19 guidelines and policies to remain safe while conducting field work. The project also accommodated the water company’s COVID-19-related challenges.

“The biggest wins for the Weldon Spring Site Waterline Replacement Project are pretty straightforward,” said Site Lead Randy Thompson. “We had a 30-year-old, antiquated, wrong-sized system and replaced it with a modern, reliable, right-sized system. We reduced the amount of legacy material left on site, and we did so without incident or injury.”

The South Area trench is backfilled and graded.

The South Area trench is backfilled and graded.