Gas pipeline stability assessment - Lafarge Tarmac and Transco

Gas pipeline stability assessment - Lafarge Tarmac and Transco

We were jointly appointed by Lafarge Tarmac and Transco to prepare a pipeline stability assessment for an existing gas pipeline running through the proposed Lanton Quarry in Northumberland. This included designing the standoff and protection works needed for the pipeline to stay in place, and calculating the volume of saleable sand and gravel that would be sterilised.
 
Although the pipeline was protected by a grant of easement from 1970 this only related to the surface, providing a 12.1m wide access corridor along the length of the pipeline. In preparing the assessment it was important to consider the proposed depth of the mineral workings, the groundwater level, and the geology of the area. Using SLOPE geo-software we were able to calculate a safe pillar of support and the angle of batter (?) required on either side of the pillar. Using these criteria we then calculated the volume of mineral that would be sterilised.
 
By jointly working for both parties, we were able to produce an independent report which was accepted by both - reducing the level of professional fees incurred by both sides. We then went on to represent Lafarge Tarmac in negotiating compensation for the sterilised mineral with Transco.