Tunnel Quarry

The surface area immediately above the underground workings was surveyed and contoured at five-foot intervals and plans prepared showing the correlation between surface and underground areas. The completed plans were passed to the War Office Tunnel Quarry Committee who were to decide upon the layout of the storage areas. 

Some clearance had been undertaken at Tunnel Quarry with the consent of Bath Portland Stone prior to July, 1935, to allow Captain Terry and his team of surveyors, together with the civilian consulting engineer Forster Brown, access to the remoter areas of the mine to compile their respective surveys. 

In June, 1936, when the War Office drew up a preliminary schedule of works to be completed at Tunnel Quarry, it was thought desirable that as much as possible of the work should be done either by Royal Engineer detachments or by directly employed civilian labour. Certain specific tasks were, however, to be done by private contractors. 

Although the slope-shaft was finished it was likely that Main West would be required for the evacuation of debris for at least another twelve months, so temporary means similar to those employed at Tunnel Quarry were adopted to get ammunition into the storage districts. A vertical ventilation shaft at the west side of No. 12 District was fined out as a winding shaft, with a small engine-house on the surface to house a... 

A Samson coal cutter at work in Tunnel Quarry in 1936. Note the rotating head slewed horizontally to undercut a large stone block. 

Tunnel Quarry Main Surface Loading Platform. Smoke in the background is from the boilerhouse chimney, which is directly behind the MSLP. 

Tunnel Quarry switchroom, with transformers in the background and indicator panels on the left. 

A large issue of anti-tank mine fuses being entrained from the south face of the underground loading platform at Tunnel Quarry in 1943. The portable gravity runways are linked to the belt conveyor on the platform. 

Tunnel Quarry. A train of ammunition wagons is drawn into the depot by one of the WD Hudson-Hunslet... 

This view of the Main East haulageway at Tunnel Quarry shows boxes of contact mine fuses being despatched from No. 5 District onto the low-belt which will carry them to the north face of the underground railway platform. 

Rearmament gave the impetus to start the improvements at the CAD first proposed three years earlier. Works authorized at this time included the upgrading of the temporary districts at Monkton Farleigh, pillar strengthening in Tunnel Quarry and enhancements of the air-conditioning and ventilation in all the quarries. A further 135,000 schedule of new works, principally the improvement of the various temporary loading platforms, was not proceeded with due to financial restrictions. 

There had been a temporary setback in April following complaints from Golonel Minnis, the RE officer in charge of construction at the War Office Tunnel Quarry ammunition depot. Slight roof movements had... 

Tunnel Quarry (continued) Boilerhouse, 74 Closure, 141 Completion, 63 Construction, 48 Conveyors, 59 Cordite storage, 66-67 D-Day issues, 134 Drainage, 62 Elearic trucks, 68 Flooding, 32... 

Electric trucks at Eastlays, 109 Locomotives, main line, 68 Overhead rope haulage, 65, 82 Railways in Monkton Farleigh Quarry, 90 Tunnel Quarry, 65 Uniformity allowances, 215 United States Air Force, storage requirements at Corsham, 177 United States Army, 6833 Guardhouse Overhead Detachment, 233 United States, Neutrality Act, 111 University of Bristol, archive storage, 45... 

Doubt was expressed as to whether the new works could be contained within the million budget, and the estimate was carefully examined to see whether it was possible to reduce some of the items to meet the new requirements. Further work on Ridge Quarry was abandoned, as was the west end of Tunnel Quarry where conditions were particularly bad. Ridge was commissioned as a temporary store and the abandoned area at Tunnel, which was to have been No.l District, was later utilized as a secure defence communications switching centre known as South West Control . Full air-conditioning was to be installed only in Districts 21 and 22 at Eastlays, which were required for cordite storage. 

Provision of premature storage at Ridge, Eastlays and Tunnel quarries 120,000... 

The layout of the storage areas at Tunnel Quarry was determined by... 

The strengthening work necessary at Tunnel Quarry consisted of the repair of existing pillars and the provision of further permanent works to ensure that the overhead cover was adequately supported. It was considered at the time that the roof was so sound and the overhead cover so deep that there was no danger of it breaking up imder bombing attack, but there was some doubt that it was sufficiently supported as a mass. Colonel Minnis noted to the War Office Tunnel Quarry Committee that ... 

Hudswell lift shafts were completed in June but the electric lifts would not be available for a further eighteen months. In the meantime the War Office had ordered that the depot should commence receipts of ammunition from the factories on 1 July. At the time it seemed impossible that this could be accomplished, so labour was withdrawn from the works at Eastlays and Ridge and concentrated at Tunnel Quarry to meet the deadline. Hudswell No. 1 lift shaft was hurriedly fitted with a secondhand steam winch and makeshift lift cages, and on 13 July, 1938, within thirteen days of the scheduled date, ammunition started to arrive. 

In a well-ventilated mine the most favourable conditions for storage purposes obtain during the winter months when the air can hold only a small absolute amount of moisture even when saturated. It was unfortunate that the first measurements of humidity were taken in isolation at Tunnel Quarry in March, 1937, at a time when atmospheric conditions underground would have been at their best, inevitably giving rise to erroneous conclusions. 

Tunnel Quarry No.5 slope-shaft just after completion, looking up into the Main Surface Loading Platform with the belt conveyor to the left of the steps and the runway for winch-hauled trucks on the right. 

ATS Corporal Edna Bullcn operating the underground private branch exchange at Tunnel Quarry in 1943. 

The generating plant was ordered under the same contract as that at Tunnel Quarry. There were a number of special conditions to the contract which are interesting to recall, bearing in mind that the contractor was only being asked to supply their standard product. Only British workmen were to be allowed to work on the manufacture and installation of the plant, and only British or Empire materials were to be used. No duplicates of any drawings were to be produced, and all annotations describing the function of the various parts were to be erased, even on drawings issued to sub-contractors. Final assembly of the complete equipment was to be undertaken in a comer of the factory securely screened off from the rest of the works. 

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