Excerpt:

The Navy has completed the final round of inspections and cleanup of the last traces of the radioactive metal called Radium-226 in Building 5 at Alameda Point. The aircraft hangar complex is where the Navy refurbished its planes, including repainting tiny instrument dials, switches, and markers with glow-in-the-dark paint that contained radium.

Radium is a naturally occurring element found in miniscule amounts in soil and water posing no health risk. Its risk comes from ingesting the element regularly, such as in industrial settings.

The procedures for handling and disposing of the paint waste during the 1950s and 1960s led to costly and seemingly interminable cleanup projects once the base closed in 1997. This affected at least five other areas at Alameda Point.

During the summer, the Navy’s contractor scanned floors, walls and ceilings to detect paint residue and radium dust. The potentially affected areas were confined to a small part at the center of the 910,000-square-foot complex. This was a follow-up to the 2010 scanning and removal work.

Using scanning bars, varying in length from three to five feet and wired to a computer, data was mapped centimeter by centimeter. Ventilation duct work, insulation, drop ceiling, lighting, drain pipes, paint booth walls, office walls and a brick wall were removed. Pockets of the concrete floor were removed with a grinder down to a depth of one inch and refilled. The Navy set a conservative threshold for clearance to meet residential standards, even though only commercial and light industrial is planned for the building.