Site Name: Little Heath (FFD1) Forward Filling Depot
Sub Brit site visit 6th November 2003
[Source: Nick Catford]
Barnham Heath is a largish area between Barnham and Thetford part
of which is still used for military training (Barnham Camp) and part
of which is in private hands. There were two areas of the heath related
to chemical weapons (mustard
gas). The north site later became the 94 Maintenance Unit Nuclear
Bomb Store and is now the Gorse Industrial Estate. The south site
(south of the Barnham - Elvenden road), most of which was sold to the
Elvenden Estate, was the site of the Little Heath Forward Filling Depot
(FFD) and the three 500 ton bulk storage pots. This area comprises 1.7
acres and is crossed by a public right of way. The depot remained in
MOD hands until April 1997 when it was handed over to the Defence Land
Agent prior to sale.
Photo:Charging building where the weapons (bombs and spray tanks) were filled with the chemical agent
Photo by Nick Catford
The chemical name for mustard gas is dichlorodiethyl sulphide. At normal temperature it is a liquid, rather like diesel oil in appearance with a smell similar to garlic. It was used as a war gas because it is a 'vesicant' which means that contact with the liquid or vapor will cause blisters on the skin similar to third degree burns and if inhaled will cause serious damage to the lungs which will almost inevitable cause death. Its value in conflict was due to the fact that it does not decompose and will remain active in the ground or on materials it has contaminated for many days, in fact months or even years. This makes it completely different from the effects of chlorine or phosgene which, as gasses, are readily dissipated in the atmosphere.
It is comparatively easy to manufacture given a supply of raw materials which are mostly readily available chemicals and there are really only two effective ways of decontaminating; one is by the application of bleaching powder and the other by burning.
There are two types of mustard gas, Runcol (HT) which is produced by the method used by the Germans in WW1 by reacting thiodiglycol (known as 'Syrup' during the war) with hydrochloric acid and Pyro (HS) which is produced by combining ethylene with sulphur dichloride. Runcol was more expensive to manufacture and was not suitable for tropical storage.
Chemical warfare was developed in Germany in 1915 but the allies were
quick to respond with their own production and in the later years of
WW1 mustard was used by both sides. Although chemical weapons were banned
by the Geneva Protocols of the 1920's this did not stop their use by
the Japanese in 1931 and the Italians in 1935 and even Churchill supported
their deployment. With the coming of WW2 it was decided that the manufacture
of chemical weapons should once again be undertaken to act as a deterrent
as Germany would almost certainly be producing them.
Photo:Plan of Little Heath FFD
Mustard gas was produced by ICI from 1938 at their Randle plant on Wigg Island near Runcorn in Cheshire and initially weapons were filled or 'charged' at Randle. It soon became clear that a safe storage facility was required for these weapons and in 1939 work started building the Valley Works at Rhydymwyn in North Wales.
In 1941 it was proposed that five forward filling depots (FFD) should
be constructed and they were ready for use by 1944. The five depots
The layout of the five FFD's is similar, the major buildings being storage sheds for empty cases, a bonding building, a charging building(s) where the cases were filled; these buildings were linked together by covered ways . There were also underground storage tanks knows as 'pots' where the chemical agent was stored; at Little Heath there were three of them, each holding 500 tons of chemical agent. At Little Heath there were two charging buildings and a railway loading dock inside the bonding shed with a short spur from the Thetford - Bury St. Edmunds Railway Line.
Photo:The empty storage building
Photo by Nick Catford
No munitions were filled at the site after 1945. Immediately after the war, due to the danger of storing filled munitions over long periods, it was decided to decant agent out of the 65 lb LC (light case) bombs and the spray tanks into storage tanks and dispose of the munitions by incineration followed by dumping.
Stocks of new munitions continued to be stored at the site in case new supplies were needed and in 1946 unspecified quantities of mustard were taken to the Valley Works at Rhydymwyn in North Wales for storage in support of a continuing military requirement.
Further information and pictures about this site continues here
[Source: Nick Catford]