By the time planning permission for a deep underground laboratory at the Thorp reprocessing plant in Sellafield, Cumbria, was refused in March 1997, 200M had already been spent on what is arguably the most detailed site investigation ever conducted in the UK.
Between 1989 and 1997, geological and hydrological investigations were carried out to assess the suitability of the underlying Borrowdale Volcanic Group, for deep storage of low and intermediate level nuclear waste. Twenty boreholes to maximum depths of 1,900m were put down, plus about 2,000km of seismic surveys and 8,000km of airborne geophysical surveys.
Nirex argued the need to construct an underground laboratory to confirm the suitability (or not) of the site and which could eventually be incorporated into the 2bn deep level repository consisting of six, 600m long galleries and 10km of access tunnel. But plans were scrapped by Conservative environment secretary John Gummer on the grounds that the site was too difficult (and expensive) to characterise.