A secretive planning application for a new facility at an arms factory in the Monmouthshire countryside has been approved by officials behind closed doors.

A decision notice, stating that Monmouthshire County Council has approved the application at arms manufacturer BAE Systems’ Glascoed site, has been published by the local authority.

However plans related to the new dual fuel four boiler energy centre haven’t been made available on the council’s dedicated planning website, though they can be viewed by appointment at County Hall in Usk.

Applications normally include drawings detailing proposed buildings, including their height and scale, and a raft of supporting information while the council has to publish an application form and a detailed report from

its planning officers outlining how the proposal was assessed and how the decision to either approve or refuse was reached.

But instead two statements, from the council, have been published which state: “Due to the sensitive nature of the site, full details of the application can only be viewed by appointment only at County Hall. Please note that none of the information can be copied/retained/published.”

The one statement confirms the energy centre, including the boilers which will run on natural gas with gas oil as a backup, and used to “provide steam for the munitions factory site”, will measure some 22 metres in length, 17m in width and 11m in height.

The statement adds: “It will be located within the BAE Systems site, among other buildings i.e. next to the existing boiler house. The size of this Energy Centre is smaller than the existing boiler house.”

Concerns raised by environmental body Natural Resources Wales have been published on the website, and it says they can be overcome by placing conditions on lighting, to protect roosting bats on the site, and to prepare for the discovery of any unexpected contaminated land.

Glascoed, which is on the southern side of the A472 between Usk and Pontypool, was originally developed in 1938 as an ammunition filling factory for the Royal Navy in the run-up to World War II.

According to BAE Systems’ website a workforce of several thousand were employed to build the factory which was declared “operational” on March 31, 1940 when its first shell filling was completed.

The factory was attacked by the German Luftwaffe in both July and October 1940 with several workmen injured and one killed in the second raid. Later examination of German records showed the aircrews thought they had actually attacked the aircraft factory at Filton some 40 miles south on the opposite side of the Severn Estuary.

The site continued to produce ammunition throughout the war for all three services and had a workforce of more than 12,000 operating over three shifts.

Glascoed was privatised by the Thatcher government in the mid 1980s.

The current owners signed an initial 15 year £2 billion contract with the UK Ministry of Defence to supply ammunition to UK troops, for training and use on frontlines, in 2008 which included a £34 million upgrade to manufacturing and infrastructure at Glascoed.