3.1 The Invitation to Tender and Invitation to Continue Negotiations envisaged that a number of services would be included in the project's scope and defined in Service Level Agreements. When GCHQ selected IAS as preferred bidder, some of these Service Level Agreements had yet to be negotiated to reflect GCHQ's service requirements over the contract period. As a result, the final cost of those services had not been determined.
3.2 Also, the invitation to tender did not specify a location for bidders, other than stating that it must be within a ten mile radius of Cheltenham. When the preferred bidder was selected, there were two possible locations, the existing Benhall site and a green field option at Gloucester Business Park, in Brockworth, some five miles from Cheltenham, under the control of Tewkesbury Borough Council.
3.3 IAS's "Doughnut" design was flexible enough to be accommodated on either site; however, the sites were not identical, and these differences had to be recognised in the building design. In order to provide bids for both sites, therefore, IAS had to maintain separate design models and costs for each location. This increased their bidding costs until GCHQ selected the final site.
3.4 The requirement to provide bids for both sites was maintained in order to apply pressure on the local planning authorities so that they worked with IAS to overcome the significant planning and local political issues at each place. GCHQ said that this ensured that neither GCHQ nor IAS was held to ransom by any party. GCHQ made their choice once both sites had become viable options.
3.5 GCHQ analysed the costs and benefits of each site, including non-financial factors. The initial financial analysis slightly favoured the Gloucester Business Park site. However, this did not take account of environmental factors or the costs of providing temporary telecommunications between the existing and new sites.
3.6 GCHQ then sought the advice of the Department of the Environment, Transport and the Regions on the environmental impacts of the site choice. Most GCHQ staff lived in the Cheltenham area and a move to Gloucester Business Park would increase the number of car journeys and be detrimental to the environment. As a result of these environmental and other, unquantifiable, factors, GCHQ chose the Benhall site in May 1999, some eight months after preferred bidder selection.