WIPP upgrades makes progress

24 June 2019

Substantial progress is being made in capital improvement projects including the USD288 million Safety Significant Confinement Ventilation System (SSCVS) at the Waste Isolation Pilot Plant, the USA's only repository for transuranic wastes, according to the US Department of Energy Office of Environmental Management (EM).

Welder Ismael Duarte works in the WIPP underground, where has several maintenance and fabrication shops have been carved out of the salt layer. (Image: EM)

"There's so much infrastructure work happening [at WIPP], the view literally changes daily," EM said on 18 June.

The SSCVS will replace the New Mexico deep repository's existing underground ventilation system and will significantly increase the airflow of the underground portion of the WIPP facility from 160,000 cubic feet (4530 cubic metres) per minute to 540,000 cubic feet per minute. This will enable waste emplacement activities to be carried out at the same time as facility mining and maintenance operations, and is critical to EM's plans to increase shipments of transuranic waste to WIPP from DOE cleanup sites.

EM has previously said the SSCVS is key to full operations at WIPP following an underground truck fire and unrelated radiological event in 2014 which led to a suspension of operations at the site lasting nearly three years. The largest construction project at WIPP in almost 30 years, the SSCVS is scheduled to be completed by 2021.

Surface work to create trenches for power, water, and sewers to multiple WIPP projects (Image: EM)

Work is also progressing on other major projects at the site and around its perimeter, EM said. The pre-engineered fabrication assembly building, where SSCVS components will be assembled, has been delivered to the site and excavations for its foundation have begun. Underground piping has been completed for the salt reduction building, where filtering machines and other equipment will remove salt dust and other matter from air coming from the WIPP underground. Subsurface excavation is under way for the filter building, where air from the salt reduction building will pass through progressively finer filters to trap contaminants before exhausting to the outside via a stack.

Land has been cleared for the site's fifth and largest utility shaft, which will descend to the 2,150-foot level of WIPP’s underground. With a diameter of 30 feet, the shaft will provide air intake plus a possible third point of access for workers and materials into the WIPP mine, and is due for completion in August 2022.

Work is also under way on a bypass road to relocate non-WIPP traffic away from the site and the utility shaft construction zone. Maintenance and upgrade work is also being carried out on the site's lightning protection system and fire protection loop.

WIPP is excavated out of a natural rock salt layer 650 metres below ground, and has been operational since 1999. Wastes which are sealed in steel drums are placed on pallets and stowed in excavated rooms or caverns. The salt is plastic and will eventually seal the wastes and isolate them permanently. The TRU waste disposed at WIPP includes clothing, tools, rags, residues, debris, soil and other items contaminated with small amounts of plutonium and other man-made radioactive elements from the US military programme.

Researched and written by World Nuclear News