Rhydymwyn - Valley Works Complex
| Location: | The Alyn Valley, south of the A541, 3 miles North West of Mold, Flintshire | |
| Nat. Grid Ref: | SJ205668 | |
| Date of last visit: | 1998 |
The area has a layer of exteremly pure limestone running through it, up to 900ft down and 200ft thick in places. The works was originally used for mining, however it was considered commercially un viable due to market changes, and so the government gained control of the site.
the site was selected in 1938 as the UK site for the storage and production of Chemical weapons, which carried on for many years.
In this time a six mile, 24" pipe for waste disposal, was laid in complete secrecy to the Dee estuary. emissions were classified as "acceptable risk to the populous"
In 1940, four tunnels with blast doors were completed, giving the site storage of over 5100 tons of munitions, with an overflow of a further 2000 tons at nearby woodside. It took 2200 miners and personnel to build , who were told that they were preparing storage chambers for the national treasures, which in fact were stored at the grange site, further north.
No damage was ever caused to the site during World War Two, in fact it was the only UK installation that was never discovered by German intelligence.
Safety at the site was not as it is today with this type of installation and there was over 930 accidents at the site, with 20% of them rated as either very severe or fatal.
In the mid forties a move was made towards using the facility for the UK atomic weapon research programme. Officially the plant was put over to researching "synthetic Rubber"
Because of this facility, in 1972 when the MOD established regional HQ's around the country, north wales intentionally had no such facility, to ensure that no attention was drawn to the area.
The valley site is now unused and is controlled by the PSA (now called Property Holdings) and MAFF.
Recently 5 members of SUBBRIT were given unrestricted access to the site. Details of their visit can be found on the Subbrit site, along with photographs of the location.
A more detailed history can also be found on the subbrit site.
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