• Client: Cadent Gas
  • Category: Gas Distribution - Pipelines
  • Duration: 11 Weeks
  • Location: Wiggenhall St Germans

Project Background

A gas escape was detected on the West Winch to Paradise Farm 19 bar, 8” high-pressure pipeline at Wiggenhall St Germans, Kings Lynn.  

PPV Group Ltd (PPV) were appointed as Principal Contractor and Designer to assist with the emergency response and remediation of the damage pipeline. 

Our Solution to deliver the works

  • PPV were to fulfil the role of Principal Contractor (PC) & Designer. 
  • Design & co-ordinate temporary works throughout the project. 
  • Build a program of works using Microsoft Project. 
  • Engage an Ecologist to monitor and mitigate a live badger sett to facilitate a dense vegetation clearance. 
  • Topographic & drone surveys to complete land condition survey. 
  • Liaise with local highway authority, deploy an emergency road closure, and install temporary road surface allowing access to local residents. 
  • Liaise with UKPN the regional Distribution Network Operator to obtain GS6 permitry. 
  • Soil strip two agricultural fields and import crushed stone to create site compounds. 
  • Mobilise site across two field locations to adhere to CDM 2015 regulations inclusive of welfare, vehicle/pedestrian segregation & security to facilitate gas non routine operations.
  • Excavate eight deep excavations, install shoring and emergency equipment for safe entry. 
  • Support & control National Grid PMC & Cadent Gas activities during hot tapping and stopple operations to install the High Pressure (HP) bypass pipework. 
  • Cut PRS concrete base using high pressure water jetting system. 
  • Assist Authorising Engineer (AE) Operations with hydrostatic testing and installation of 24 meters of new 8”/ 219mm steel HP pipeline. 
  • Cast new concrete base and install new PRS GRP kiosk. 
  • Construct four composite inspection chambers and install lightweight covers. 
  • Engage and co-ordinate G17 designs for palisade fence, inspection chambers and paths. 
  • Install 2.4m high palisade fence, with vehicle and pedestrian access gates. 
  • Highway resurfacing and reinstatement to HAUC specification. 
  • Install bollards to prevent agricultural vehicles crossing the HP pipeline. 
  • On completion, clear site and reinstate back to original condition.
  • Submit information to the client for handover/ sign off, uploaded CE certification and cube test results. 

Providing Solutions From Start To finish

Our Project Manager took on the role of Designer. Aligned to the scope of works, we utilised our Approved Vendor Process to appoint a temporary works designer to carry out the excavation temporary works designs. Temporary pipe supports were installed as per Cadent G19 Designs. Our permanent works designers were appointed to undertake the permanent works for the PRS. Palisade Security Fencing, Composite Inspection Chambers and Boundary Timber Fencing. All permanent work designs went through Cadent’s G17 procedure. We managed all design co-ordination as per the Designer requirements as detailed in CDM. Regulations 2015 and held regular client and partner engagements to ensure all parties were confident of the solution to be deployed. 

Our Project Manager had ultimate responsibility for the co-ordination of construction activities, all of which were detailed within our Construction Phase Plan and associated documentation. We engaged Surveyors, Ecologists, UKPN, Network Rail and Land Officers highlighting and mitigating any significant risks or constraints. PPV produced a CDM Layout 

Plan, created a Site Health & Safety file, and implemented a Sensible Monitoring Plan for audits and inspections. Prior to the start of the works, we participated in a HAZCON meeting to ensure all hazards had been identified and planned for. We also ensured all Permits to Work were in place, which were applicable to the works being carried out. For this project we worked to Cadent’s permitry in such areas as, General Works including Site Mobilisation, Deep Excavations, NRO’s and Lifting Operations. 

To deliver the project requirements in addition to the in-house resource we had appointed, we engaged with relevant suppliers through our Approved Vendor Process, ensuring we deployed support which was competent and capable. We held regular project engagement meetings with our sub-contractor management teams, as well as engaging the site staff on a more frequent basis, through inductions, daily briefings, and toolbox talks. This on-going approach ensured the project team all had access to real-time consistent information. PPV also worked closely with PMC and Cadent Op’s during the mechanical works and Non-Routine Operations. This involved site inductions, briefings, supplying suitable tested plant and equipment, radios to co-ordinate the works running simultaneously in two locations, lifting operations, supply emergency and rescue equipment (gantries and harnesses).