Update on progress of Medium and Long-Term Solutions

FH invited GR and Rory Gunn (RG) of AWJV to provide an update on the ongoing ground investigation work, and the medium and long-term solution.

RG provided an update on the LTS and MTS including an update to design works, an overview of the statutory process timeline and an update on the ongoing ground investigations.

A copy of the slides can be found in Annex B.

FH thanked RG for his presentation and asked attendees if they had any questions.

Lucy Sumsion (LS) asked in terms of the constructability assessment, following the events of this week, what measures will be put in place should a landslide occur during construction? LS continued to ask if once completed, if there is a landslide and debris is caught in the catch pit behind the shelter and vehicles are mobilised onto the roof to remove material, will the road remain open?

RG noted that none of the options considered at DMRB Stage 2 were completely immune to the risk of landslides, including the green option. With regards to constructability, consideration is being given to constructing additional fences above the A83. As the scheme construction develops, the catchpit and debris flow shelter will aid resilience. RG also noted that plant and machinery will be able to operate on the roof without the need to close the A83.

Fergus Murray (FM) asked about the construction impact on the A83 and diverting onto the OMR for such a significant period of time. What economic assessment has been done here?

RG responded that the improved OMR (following completion of the MTS works) will be in operation for extensive periods during construction. The social and economic impacts are being assessed now and will be reported in the DMRB Stage 3 report.

GR added that disruption to road users was considered during DMRB Stage 2 which fed into the assessment process for the preferred route.

FH noted that the preferred route has been identified and work is now ongoing to minimise disruption to road users during construction. The role of the Taskforce is now to work together to build resilience through this period.

John Gurr (JG) noted the helpful discussion in the summer around providing a two-way road during construction, which JG agreed would not be possible. JG would like to see the details of the economic assessment as the DMRB Stage 2 assessment only reported a high/medium/low scoring, and what contributed to getting to these scores?

RG responded that the Stage 3 assessment is much more detailed than Stage 2, and that assessment work is well underway and will be published at the end of this year.