Twin Bases - RAF Bentwaters, RAF Woodbridge

Building 398, inside the WSA - Weapons Storage Area (a.k.a. Bomb Dump)

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While visiting the base with Walter Smith and Jerry Epley and their wives, we took a peek at the very interesting Building 398, which housed a very strong safe, and storage for 'inert edm materials' and for 'live edm materials'

The sign attached to Building 398.
1. The sign attached to Building 398.


The safe, inside building 398, inside the WSA at RAF Bentwaters.  
2. The safe, inside building 398, inside the WSA at RAF Bentwaters.


The floor markings for "INERT EDM MATERIALS".
3. The floor markings for "INERT EDM MATERIALS".


The floor markings for "LIVE EDM MATERIALS".
4. The floor markings for "LIVE EDM MATERIALS".

I was hoping for some input from my helpful 1,200+ ex-Bentwaters email contacts to explain the purpose of this building and the floor markings.
Did I hope in vain?
I did not! See below:

From: Croisant, Kenneth R. [kcroisant(at)]
Sent: Monday, June 06, 2005
The 398 photo's are very normal when you know what they mean.  If the storage area were about to be overrun by the bad guys, you wouldn't want them to have the material stored there.  The live EDM material was explosives used to destroy the material under those dire circumstances.  (I am not aware of any instance of a storage area being intentionally destroyed, but perhaps during WWII.)  The inert EDM material is the fake explosives used to practice destroying the storage area, which we were required to do from time to time for the inspectors.  Remember, we had to meet all US, UK, and NATO requirements at the same time and being able to destroy the storage area was a requirement. 
All the best,

From: Randy R. Pischel [rpischel(at)]
Sent: Monday, June 06, 2005

As you know (maybe) I worked in the WSA for three years in the 80's. EDM stands for Emergency Destruct Munitions and the inert ones were for practice and the live ones were for real life. Once a month or so we'd wire the entire WSA up with the inert EDM materials and simulate a total destruction of the WSA and time how long it would take us. It was always a nerve-racking exercise as we would actually be attaching things to the nuclear weapons under armed guards, and the guards were us (munitions people) rather than regular Security so that they could detect an "unauthorized" action. Regular security just backed them up.

The safe was already out of use when I arrived but here are two very interesting stories about it. One, we used to lock new people in there for initiations to the WSA. When inside with the door closed it is utterly, utterly dark and quite freaky. Two, we used to tell people that parts to UFOs were kept there as it was absolutely the safest place on base, after all it had two combination locks that required two different people to open (no one person could know both combinations), two people to open the door to the building (for the same reason), you needed security to get into the WSA which was inside the flightline, which was inside the base. So, you'd need at least 5 people just to get into the vault so that's where the UFO parts were. This story has turned up on some UFO sites so we must have made an impression.

Also, 658 and 659 just had administrative people in it. It used to be full of those cubicles you see in open offices.

Man, those pictures brought back many memories.

Randy R. Pischel
Acting MIS Director

From: Kenneth Greene [mailto:delgrene(at)]
Sent: Monday, June 13, 2005 12:01 PM

Regards the recent photos of the WSA building; "edm" is the acronym for emergency destruction of munitions. A procedure called EDM was in place in the event the bases would be overrun by enemy forces. The WSA would be wired up and destroyed with conventional explosives to prevent the resources stored there from falling into enemy hands. The safe was used to store the munitions required for this procedure. The inert EDM was used when testing the procedure during inspections, etc.
The safe most probably contained the charts for the explosive wiring diagrams, as well as the actual munitions used to implement the EDM.

Ken Greene
Former 81 SPS



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