“We are looking forward to building a long-term, collaborative approach with NWG and delivering an excellent standard of work. Having previously worked on this framework, I know how important a co-operative approach and a highly-skilled workforce is to success, both of which CSC Services can bring to this relationship.”Heston Craiggs Framework Delivery Manager
Various areas of concrete deterioration and seal ingress had been identified at the service reservoir. This included seal ingress at the access cover, the construction joint and the primary beam. The scope of work included repair/replacement to deal with corrosion of the rebar, access hatch fixings and spindle, as well as pipework and concrete wall clean and repair.
Hatch Seal Ingress Repair
Existing sealant material was removed from both the metal frame and concrete upstand surfaces before a new sealant was applied and allowed to cure. A full flood test was carried out following works to ensure quality of work.
Joint and Beam Ingress Repair
The external tank perimeter was hand-excavated to expose the outer wall surface to located point of ingress. The defect location was then prepared and waterproofed with a polyurethane/urea liquid bonded membrane system and the area backfilled.
Corroded Spindle Repair
The damaged spindle and guide were removed before being replaced.
Primary Beam Repair
Any defective concrete was broken out before repair sites were then cleaned out and refilled with a fast-setting repair mortar.
Hatch Fixings Repair
The defected area was broken out and corroded fixings removed to a minimum of 10mm before repair sites were cleaned out and refilled with a fast-setting repair mortar.
Hand tools were used with portable clean water to remove surface corrosion on all pipework, valves and flanges, while removing tubercles. All work avoided removal of any existing coating system.
Identify Wall Recoating Requirements
High-pressure water jetting was used to remove existing defective coatings from the walls and form a suitable key to allow further cementitious levelling coating in line with Regulation 31. Floor slabs were also cleaned using the same methodology.
A flood test was carried out before a final clean was undertaken of the tank using high-pressure water jetting. All waste from the clean was jetted to the sump area before being removed.
All works were carried out on-time, on-budget and to client satisfaction.