BBV HS2 MWCC North - Secondary Permanent Ground Markers Installation and Determination

About the Opportunity: Balfour Beatty VINCI (BBV) have been awarded HS2 main works civils contracts, lots N1 and N2 under an Early Contractor Involvement contract (ECI). We are currently in stage one of a two stage process.

We are looking to engage with the local supply chain whom provide surfacing works across multiple sites.

Full details and specifications will be provided to the successfully shortlisted suppliers. Suppliers should be aware of the scale of this project and should assess their internal capabilities to be able to carry out the intended scope of works, prior to completing this expression of interest (EOI).

Additional information: The scope of the subcontractor can be summarised in the following activities:

• Quality check of the existing Primary PGMs. • The Staking of new Secondary PGMs following a setting-out drawing inside the delta Junction, it is approximately 60 points • The installation of new Secondary PGMs except where it will be decided to install pillars by Delta junction team • The measurement of the PGMs using Post Processed Kinematic techniques for X/Y and a double way levelling for Z connected to 1st order PGMs • Report including measurements and be in the form of Witness Diagrams of the Survey PGMs.

Details of the Works to be Undertaken

The Supplier shall undertake a Risk Assessment prior to each installation and ensure a Safe System of Work is in place before the works can proceed.

Quality check of the Primary PGMs

It will be necessary to control the points surrounding the Delta Junction (see figure 3) following the instruction HS2-HS2-GL-STR-000-000001 and HS2-HS2-GL-PRO-000-000003 PGM inspection and maintenance process and if need apply correction.

The CORS stations will be fixed. The Primary PGM's newly calculated values will be compared to the issued values and communicated to the Client. The Primaries will then be fixed and the Secondary PGM's will then be calculated.

Permanent Ground Markers (PGM) establishment was undertaken by Bridgeway Surveys (on behalf of High Speed 2 (HS2) in 2016 and 2018.