Published in March 2016
This is a classic example of the geotechnical risks involved in temporary works and slope steepening. The slope appears to have been cut in preparation for soil nailing, which could only be done after the slope had been excavated to the steeper slope. This is why careful geotechnical design is required, based on accurate geotechnical parameters from high quality investigation.
It also shows the need for good geotechnical supervision during construction works although in this case it is possible that there would have been little warning of a failure, given that it happened overnight. If the failure had occurred on a third party site outside HE land, there would be legal implications in addition to the H&S issues.