The solution came to me without an appointment or warning. One of the graduate students I'd worked with to develop the original formaldybrom had gone onto a project which was studying the radioactive contamination of San Francisco.
He came in because of the absence of radiation around my building.
The student was here to find out what I was doing that was removing radiation from the area. He told me that just taking a few paces in any direction from the building walls would send his Geiger counter up to normal for that area. But inside the building, it was completely inactive.
This was easy to detect as the block the building was in generally had higher radiation activity than others. The warehouse was on Treasure Island, which was earlier used for decommissioning ships that were expose
