More than 30 piping repairs were made last month at the Savannah River Site’s aging H Canyon nuclear materials processing facility during a planned maintenance outage.
Along with the repairs, site personnel used the outage to calibrate the facility’s electrical breakers and inspect its air tunnel, which has sustained corrosion over the years. “Regularly scheduled maintenance outages are an industry standard,” SRS spokesperson Monte Volk said of the break in work, which ran from March 25 to April 11.
Fluor-led Savannah River Nuclear Solutions (SRNS) runs H Canyon as part of its site-wide management contract, now under a one-year, $1 billion extension that expires on July 31 of this year. The 64-year-old canyon processes materials, such as highly enriched uranium (HEU), and repurposes the material as an energy source for nuclear power plants.
Maintenance outages are generally scheduled every spring and fall to address degradation in various components. “SRS management schedules two maintenance outages each year in H Canyon to depressurize the steam system so the piping and fittings can be inspected and repaired,” according to Volk.
Steam at H Canyon is used to heat process vessels and the pipes that transport the steam to the vessels. During the recent outage, more than 15,000 feet of steam piping at H Canyon was inspected, along with 50,000 fittings that connect the pipes. Due to attrition, 32 of the fittings developed leaks and were replaced, Volk said.
Workers also calibrated the facility’s electrical breakers – removing, cleaning, and testing them to make sure they were still in working order. The breakers were then reinstalled.
Finally, the outage included an inspection of the H Canyon exhaust air tunnel, where workers discovered corrosion in 2017. The tunnel is a large concrete ventilation duct connecting the facility to its air ventilation system. Savannah River Nuclear Solutions determined that about 2 inches of the 20-inch thick duct walls had corroded over the 60-plus years that the canyon has been operating.
Volk said a remote-controlled vehicle with video capabilities was maneuvered through the tunnel for the inspection. The video showed no significant changes in the corrosion.
There is no specific cost estimate for outage work since the money comes from the H Canyon operating budget.
In December, workers noticed roughly 6 ounces of contaminated rainwater on the ground floor of the facility. The water entered H Canyon via a crack in the roof and became contaminated as it passed through the nuclear materials processing area on its way to the first level. Workers barricaded the area until the water was cleaned up.
The site announced in January that it will repair the H Canyon roof in midsummer of this year at a cost of about $1 million. A date and month have not yet been scheduled.
