Alameda Point Environmental Report: Radium Scanning Process at Seaplane Lagoon, December 18, 2011
Every scoop of dirt that was dredged from the Seaplane Lagoon earlier this year is first sorted into premeasured compartments. The piles are then tested for heavy metals, PCBs, and pesticides. But the piles cannot be tested for radium 226.
In order to test for radium, every pile has to be scooped back into a dump truck, dumped into a screening area the size of a tennis court, and graded smooth to a depth no greater than 12 inches.
Grading soil for the radium scanner
Then an electric vehicle with a scanning rig and GPS mapping system drives back and forth over every inch at the pace of a turtle. If any radiation is detected, it is mapped onto a computer, and then this area is scooped up and placed in a special dumpster. This already time-consuming process was slowed even more with unexpected rains in the fall because the soil cannot be scanned for radiation when it’s wet.