ANGLIAN SITE Investigations recently finished preliminary studies for a proposed funicular railway in Launceston, Cornwall.
The £2M, 60m long railway will link a business park at the base of an inland cliff to Launceston town centre at the top. This will be the first cliff railway built in England for 70 years and will be one of only two inland funicular railways in the UK.
Anglian senior geologist James Woodward explains that as most of the work was concentrated around the upper terminus, no special access equipment was needed. One cable tool borehole was put down to 5m on one of the only flat parts of the site, plus eight window sample holes and eight dynamic probes. Ten trial pits were excavated along the shallower parts of the route.
The main scope of the work was to determine the extent of weathering in the underlying Yeolmbridge Slate formation. Highly weathered 'Shillet' - weathered slate in a silty clay matrix - was found at the top of the site. While this appeared natural, it is thought that the material could have been dumped from excavations for a road cutting above the site.
The depth of weathering varied greatly, from between 2.7m to 4m at the upper terminus to between 1.2m and 2m further down the slope.
Because the site is close to the outer wall of the medieval town, a major concern for the project's viability was the extent of historic fill along the route. In the event very little fill was found.
Geotechnical testing was carried out at the firm's laboratories in Plymouth and at the head office in Chelmsford.
Work was commissioned by the Launceston Civic Society through funding from Shell UK.
Funding is being sought for a second phase of investigation, yet to be commissioned, to start after preliminary design is done.