The Glamorgan-Gwent Archaeological Trust
Historic Environment Record
 

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Royal Naval Propellant Factory, Caerwent

Primary Reference Number (PRN) : 11591g
Trust : Glamorgan Gwent
Community : Caerwent
Unitary authority : Monmouthshire
NGR : ST4773791495
Site Type (preferred type first) : MODERN MUNITIONS FACTORY

Summary :
The Royal Naval Propellant Factory, Caerwent was part of the Naval Armament Supply Department. Production of cordite began during WWI and with increased need during WWII a site was built in Caerwent. The site covered 1580 acres with 12 miles of standard gauge railway track and 29 miles of tarmacadamed road and approx. 1000 buildings accessible from these. 2 main independently run units were separated by a fence running approximately N to S. Both units produced gun propellants with unit 1 later producing rocket propellant and casting rocket charges.
Manufacturing consisted of the Acid, Nitrocellulose, Nitroglycerine, Cordite, Picrite and Tetryl sections and the Laboratories.
Production started in December 1940 then in December 1945 Unit 1 was put on a care and maintenance basis until it re-opened in October 1946. In 1946 and 1947 the plants ran for short periods only. A new Picrite Plant built in Unit 2, commenced production in August 1955.
The factory’s closure was announced on 25th March 1965. Site decontamination was completed in June 1968 before it was transferred to the Air Department as a nominal RAF Station on 1st Nov 1968 and made available to the U.S. Forces as an ammunitions base.
(Alexander C W, 1968)

Description :
The Royal Naval Propellant Factory, Caerwent was part of the Naval Armament Supply Department and fell within the authority of Plymouth Naval Command with administration carried out in accordance with Admiralty and later M.O.D.(N) regulations. Production of cordite began during WWI in Holton Heath Dorset and with increased need during WWII a second site was built in Caerwent.

The site covered 1580 acres with 1163 acres enclosed by a 7 ?4 mile fence with 3 road entrances, 2 railway gates, 3 ‘farmer’s’ gates and initially 1 residential entrance. There were 12 miles of standard gauge railway track and 29 miles of tarmacadamed road with the 1000 (approx.) buildings accessible from these. The factory wasn’t clearly visible from outside being partly screened by forestry and built on low land between hills.

The RPNF was divided into 3 departments; 'Process', 'Engineering' and 'Administration and Stores' which were further sub-divided. The 2 main independently run units were separated by a fence running approximately N to S. Both units produced gun propellants with unit 1 later producing rocket propellant and casting rocket charges.

Manufacturing consisted of the Acid, Nitrocellulose, Nitroglycerine, Cordite, Picrite and Tetryl sections and the Laboratories.
Services were divided into the Engineering Department, Engineering Services, Apprentice Training, Administrative Departments (General Offices, Stores, Hospital/First Aid), Fire Fighting and Safety, Labour and Transport, Work Study, Naval Ordnance Inspection Laboratory, Police, Kitchen and Canteens, Active and Passive Defence, Welfare Centre, Residences and Social Activities.

The Main Office, Main Workshops, Main Laboratory, Physics Laboratory, Fire Station, Garage, Hospital, Laundry and Kitchen were centrally located to both units and not duplicated. The residential accommodation and Police Section House were situated outside the fence mainly to the south with a small water pumping station at Sudbrook and a plant maintenance depot at Crick.

Production started in December 1940 increasing until Spring 1943 when requirements began to decrease and output went down. In December 1945 Unit 1 stopped production and was put on a care and maintenance basis until it re-opened in October 1946 for production of S C/T and S.U.K. charges. In 1946 and 1947 the plants ran for short periods only and production was negligible. Savings were made where possible until some commercial work could be obtained for the factory from Electric and Musical Industries (EMI), R.O.F. Bishopston, Northern Aluminium Co and Messrs Sheppard and Sons of Bridgend to run alongside the smaller scale RNPF work. A new Picrite Plant was built in Unit 2, commencing production in August 1955 at the same time as the RNCF plant in Holton Heath, Dorset closed. Other opportunities included investigatory work on improving manufacturing methods.

The factory’s closure for financial reasons was announced in Parliament on 25th March 1965 and site decontamination was completed in June 1968 with most of the plant sold and removed or transferred. The site was transferred to the Air Department as a nominal RAF Station on 1st Nov 1968 and made available to the U.S. Forces as an ammunitions base.
(Alexander C W, 1968)

See core 11592g for information on the extensive buildings and structures at the RNPF site. See core 09218g for information on ‘Nitro-glycerine Hill’: Scheduled Monument MM352 and core 09016g for details of building no. 318-Firing Point.


Sources :
Alexander C W , 1968 , The Royal Naval Propellant Factory, Caerwent, Monmouthshire
Subterranea Britannica , An on-line Survey of the U.K.'s R.O.C. & U.K.W.M.O. Monitoring Posts
Tuck M , 2006 , Caerwent Training Area, Army Training Estate, Monmouthshire: Buildings Survey
Tuck M & Riddett R , 2006 , Caerwent Training Area, Army Trading Estate, Monmouthshire: Building Survey. Appendix III part A.
Tuck M & Riddett R , 2006 , Caerwent Training Area, Army Trading Estate, Monmouthshire: Building Survey. Appendix III part B.

Events :
E005275 : Caerwent training area (year : 2004)
E005276 : Caerwent Training Area (year : 2004)
E005643 : Caerwent Training Area, Monmouthshire (year : 2006)

Related records
GGAT Historic Environment Record (HER) 09016g
GGAT Historic Environment Record (HER) 09218g
GGAT Historic Environment Record (HER) 11592g
National Monuments Record NPRN 87552 http://cadwpublic-api.azurewebsites.net/reports/listedbuilding/FullReport?lang=en&id=87552
National Archives Wales Ref No. 87551 http://cadwpublic-api.azurewebsites.net/reports/listedbuilding/FullReport?lang=en&id=87551

Compiled date : 29-01-2018


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