gallons (41,000 m³) of water per day, at Sudbrook, from the western end of the tunnel, conveniently located only three miles (5 km) away from the proposed site at Caerwent. Even during the great drought of 1934 the lowest daily return was 9.1 million imperial gallons (41,000 m³). The GWR used about 1.5 million imperial gallons (6,800 m³) per day themselves, so there was always a guaranteed daily surplus of 7.5 million imperial gallons (34,000 m³). Work began to create the propellants factory in 1939. A total of £4.7 million was spent on buildings and roads, and £2.5 million on plant and equipment. The site's total area was of land with a total of enclosed within the factory fence. The scale of site consumed the village of Dinham which was located at the northern edge of the RNPF Caerwent. By the end of 1940 the Main Office block was complete, and in December of that year the Unit 1 Sulphuric Acid Factory went into production with acid mixing for the Nitrocellulose and Nitroglycerine manufacturing. Five months later, the Pressure Oxidation Plant for the manufacture of Nitric acid came on stream. In August 1941 the Nitrocellulose and Nitroglycerine plants were operational and were soon working 24 hours a day on a three-shift pattern. At the same time, Unit 2 of the factory was almost completed, so RNPF Caerwent was now virtually operational. Cold War Between 1955 and 1966, Caerwent produced the Gosling solid rocket booster for the Seaslug missile. This Cold War work began in wartime buildings, the horizontal presses in Press Houses 3 and a longer press in 1, and with other work in a disused blending house and the Tetryl Acetone Recovery building. From 1957 dedicated buildings, J1...J6, were constructed on the eastern side of the site for the production of guided weapons propellants. Buildings J7...J9 at the northern edge of the site formed a static testing site, where these motors could be test-fired. J7 was an environmental conditioning building where charges could be heated to 70 °C or cooled to -40 °C before testing. These buildings were of typical flat-roofed red brick construction, shielded by large earth traverses. Testing work was also carried out here on the Magpie, Redtop and Sealyham rocket motors. Early in the 1960s a Parliamentary working party recommended that propellants for the three branches of the armed services should be concentrated at the Royal