C&EN: What do you do with a house full of explosives? Burn it down, of course.

Escondido boom-boom house:
Hey, that's a nice balance there! (Can you find it?)
(Credit: C&EN/San Diego County Sheriff)

A lot of you will remember the story of the San Diego house filled with explosives. Jyllian Kemsley writes up the interagency operation to clean up the grounds and demolish the house by building a firewall and then burning it down:

Technicians searching the grounds initially turned up six quart-sized jars filled with a white substance, 200 lb of lead sheeting, and gallons of concentrated acids as well as chloroform, hexamine, acetone, and hydrogen peroxide. Officials searching records on the property and on Jakubec learned that he had purchased castor plants. The poisonous protein ricin is isolated from castor bean oil. 

The discoveries left investigators concerned about explosive, radiological, chemical, and biological hazards at the site. To determine what was there, Vent and colleagues took air samples for biological agents and combustible compounds and sent in radiation detectors with the bomb technicians who searched the property while outfitted in both explosion and hazmat gear. Also key to the investigation was a portable Raman spectroscopy unit with a flexible sampling probe that could analyze the contents of the jars through the glass, without moving the jars or unscrewing their metal lids, because technicians feared that the contents were friction- or shock-sensitive. 

Adding to the danger of the situation were a few previous reports across the U.S. of portable Raman lasers causing samples to explode. “If you point the laser at a dark-colored substance, it will ignite,” said John Johnson, director of safety and security at Thermo Fisher Scientific, which manufactures the instrument used in the Escondido response. “When you’re pointing the laser at 1.5 lb of explosives, you have to take that into consideration.” 

A two-minute-delay timer on the Raman unit was therefore also a critical feature, so a bomb technician could set up the unit and retreat to a safe distance before the laser fired. It took a few tries to figure out how to get good spectra through the thick glass of the jars, Vent noted, but investigators eventually identified the jar contents as hexamethylene triperoxide diamine (HMTD), an explosive compound that is sensitive to heat, shock, and friction. On Friday, Nov. 19, officials shut down I-15 while a robot picked up the jars one at a time, moved them to a relatively safe location, and detonated them.

That's a pretty cool piece of technology, that Raman unit. I think there's a lab or two in this country that could use such a unit to open some cabinet doors and check some stuff out.

Seriously, the story gets hairier than what I've excerpted above. Go over there and read it.