Replacement of the moderate efficiency (MOD) pre-filters that are part of the High Efficiency Particulate Air (HEPA) filtration system for the WIPP underground ventilation system was successfully completed Wednesday.
Filter changes are anticipated and necessary when MOD filters begin to show signs of reduced airflow, due primarily to salt dust buildup. The filter change out is a well-planned and controlled work activity performed by qualified NWP staff, and because of the potential for encountering radioactive contamination, it includes the use of all appropriate personal protective equipment.
The two individual filter banks were isolated, at separate times, in order to allow old filters to be removed, surveyed and packaged for proper disposal and new filters to be installed. Ventilation was maintained, at a reduced flow rate, throughout the filter change process.
As anticipated, results for radiological surveys performed on the MOD filters that were removed indicated some low levels of contamination. However, levels found during this filter exchange were greatly reduced from those observed during the filter change out that occurred in June of 2014.
WIPP’s ventilation system for the underground facility consists of two filter units. Each unit has 84 filters, and each filter consists of four separate layers — moderate efficiency filters, high efficiency filters, and two layers of High Efficiency Particulate Air (HEPA) filters. All air exiting the WIPP underground passes through these filters, and as underground activities continue and salt dust becomes airborne, their efficiency is reduced over time.
WIPP will continue to monitor the condition of the filters and replace them as necessary.
WIPP Town Hall Meeting Today
The City of Carlsbad and DOE will co-host its Town Hall meeting featuring updates on WIPP recovery activities. The meeting is scheduled for today at 5:30 p.m. Location: Carlsbad City Council Chambers, 101 N. Halagueno Street. Live streaming of the meeting can be seen at http://new.livestream.com/rrv/.