Summary
A pair of high capacity lifts fitted and used to transport personnel between ground level and the underground Ministry of Aircraft Production (MAP) factory in the former Spring Quarry. Later adapted for access to the Central Government War Headquarters (CGWHQ).
Reasons for Designation
Personnel Lift (PL) 2 in the CGWHQ below MoD Corsham is designated as a Scheduled Monument for the following principal reasons:
* Period: the access route is testament to the importance of the subterranean aircraft factory in World War II, and secondarily to the perceived threat of nuclear strike that Britain faced during the Cold War;
* Rarity: this arrangement of a pair of high-capacity lifts with fortified shaft heads is particular to the CGWHQ;
* Survival: the lift cars, and the entrance ways with lift controls and timber doors remain largely intact;
* Group Value: the CGWHQ site is an unparalleled example of our national Cold War defence heritage, and represents the systematic use of expansive underground areas by industry and the military during the C20.
History
The Corsham Mines are a multi-layered historic site near Bath, beneath the southern end of the Cotswold Hills in Wiltshire. Quarrying of Bath Stone in the wider area took place from Roman times, and by the C18 Bath Stone had become a highly sought after building material. The opening of the Kennet and Avon canal in 1810, and the subsequent construction of the Great Western Railway in the 1840s, made the transportation of the stone to farther locations easier and cheaper, thereby increasing its popularity. Brunel's cutting of the Box Railway Tunnel, beside the village of Corsham, revealed a rich seam of high quality stone beneath the hills. Intense quarrying followed, leaving a network of quarries with worked-out chambers and air shafts, including Spring Quarry. By the time mining ceased in 1940, there were over 60 miles of tunnels across 3,000 acres, located at depths between 80 and 100 feet below ground.
The Bristol Aeroplane Company (BAC) at Filton, near Bristol was bombed in September 1940. In response, Lord Beaverbrook, of the Ministry of Aircraft Production, issued an urgent plan to relocate all production below ground, which was endorsed by Churchill. The limitations of time, suitable sites, and wartime resources quickly saw the scheme scaled back to the relocation of Filton's engine plant. In December 1940 four quarries were requisitioned by the Ministry, including Spring Quarry, to the south of the Box Tunnel. It covers a vast 3,300,000 square foot area (or 76 acres). It was intended that BAC would convert Spring Quarry for engine production in 6 months, at an estimated cost of £100,000.
However, the scale of the Ministry's factory construction project was enormous, involving the removal of thousands of tons of rubble stone, the levelling of floors, and the strengthening of pillars and roofs using steel and concrete. Lifts, escalators, and an extensive ventilation system were installed, including Personnel Lift 2, subject of this report. Furthermore, BAC became doubtful about the practicality of the project, and their involvement was scaled back. The factory was not ready for use by the end of 1942, when German bombing had largely ceased, and the need for the underground factory programme had all but vanished. The MAP factory was re-classified as a shadow factory, and proposed production was switched from the Hercules engine to the less vital Centaurus. By 1945, the factory was still incomplete to its original specifications, and its cost had risen to many millions of pounds. Engine production figures throughout the war were negligible, and the factory closed at the end of the war. MAP itself was abolished in 1946. Spring Quarry was bought by the government in 1954, when the north-east area was allocated for conversion to a secret CGWHQ for use in the event of nuclear conflict.
The first known planning for the dispersed operation of government departments, should Central London be destroyed through enemy attack, was during a sub-committee of the Committee of Imperial Defence under Sir Warren Fisher in 1937. Following the war, it was acknowledged that developments in weapons meant that the government's emergency plans were inadequate. In the light of the huge sums spent developing the MAP factory in Spring Quarry, estimated at £30 million, the Treasury proposed buying the requisitioned quarry for use as a citadel for future emergencies. However, the quarry was not bought from the Bath & Portland Stone Company until April 1954, along with 100 acres of land above ground. In 1957 the plans for the emergency headquarters were finalised; the site was intended to provide a safe haven from which the work of Government could continue. From here, the reconstruction of the country following a nuclear attack would be overseen. It was designed to accommodate up to 4,000 military and government staff, including the Prime Minister and key cabinet officials. Occupants would be sealed underground for 30 days and coordinate with Regional Seats of Government around the country, meaning that extensive communications and welfare infrastructure was needed.
Work began in 1957 with the construction of a reinforced concrete wall separating the CGWHQ area from that part of Spring Quarry used by the Admiralty. A buffer zone between the two was lined by a concrete block partition and solid rock pillars, sealing the Central Government side. Three blast doors were installed. New ventilation shafts were created and reinforced. Internal areas were divided by concrete block or, in some cases, with red brick. Five heavy duty goods lifts were installed and a ventilation system of 21 air shafts and 15 fans, some 15ft in diameter, was powered by two underground boiler houses. In order to facilitate the use by 25,000 staff, four high-capacity passenger lifts and two escalators were installed, including that in Slope Shaft A, the subject of this report. The upper, vertical part of Slope Shaft A was rebuilt with thick blast walls and ceilings, and concrete spiral stairs with railings. The original small buildings at ground level providing entrance to the shafts were replaced by new concrete bunker-like shaft-heads. Due to war shortages the escalators had to be requisitioned from London Underground, who agreed to wait for additional units that had been planned for installation at St Paul's and Holborn stations. The escalators were installed in early 1943 by the Waygood Otis escalator company.
The CGWHQ complex was never needed or used for its intended function, and was reduced in capacity over a number of phases during the late C20. The site was de-commissioned in the early 1990s. It was de-classified in 2004.
Details
PRINCIPAL ELEMENTS: a pair of high capacity lifts and lift shaft, fitted and used to transport personnel between ground level and the underground MAP factory in the former Spring Quarry. Later adapted, with a blast wall-protected lobby at upper level, for access to the CGWHQ.
DESCRIPTION: below ground the lifts are accessed by a wide doorway with six panelled timber doors with square windows to the top. They lead into a large lobby area built from brick, with a dividing wall providing passages to the two lifts. The lift control switches and controls remain on the dividing wall.
The lifts have external sliding concertina-style metal shutters, and internal sliding metal grille shutters. The lift-cars are steel-framed, lined with painted sheeting at the bottom and matchboard panelling at the top, and there is a sliding door between the two. Steel I-beams are exposed below the ceiling level, and the ceilings are plain sheeting with escape hatches within metal frames. The floors are covered anti-slip metal sheeting. There are various controls and bells affixed to the panelling, and information and warning signs. A large painted timber sign above the lift doors states 'PLEASE KEEP CLEAR OF LIFT GATES'.
The division of the foyer, and the access door between the two lift cars would have allowed organised alighting and departure for the great number of passengers.
At upper level are a vestibule and lobby, separated by a blast wall with two steel blast doors. All above ground structures are excluded from the scheduling. The scheduled area includes a 1m margin on all sides as well as above and below.
