Sanctus competitively tendered for, and won the enabling works contract for the redevelopment of Unity Street in Bristol City Centre. The contract was awarded on a fixed price all risk basis to provide the client with certainty of cost and peace of mind.
The enabling works package included;
• Asbestos R&D Survey including a remote drone survey of an unsafe building
• Utilities mapping of existing services
• Traffic management and diversions, stopping up and TTRO’s in agreement with BCC
• Ecological surveys
• Licensed Asbestos Removal, both from above ground and below ground structures
• Demolition of 8No buildings in various states of disrepair
• Façade retention of retained structures
• Site Investigation and Remediation strategy
• Remediation of asbestos contaminated soils
• Excavations to formation under archaeological watching brief
• Underground fuel storage tank removal, including validation of surrounding material left in situ
• Cut and fill earthworks, including chemical testing, waste classification and disposal of surplus soils
• The creation of Sanctus designed piling mats using suitable material and geotextile/geomembrane
• Environmental and Geotechnical conformance and performance testing to ensure suitability
• CFA foundation piling and pile attendance
• Service disconnections, diversions and installation of new utilities
• The construction of adoptable drainage and attenuation tanks
• The construction of a new adoptable highway
Prior to the demolition and enabling works, Sanctus managed the removal of asbestos containing materials from a number of old warehouse units on site. including the removal of asbestos roofing, interior material from within the buildings, and a duct known to contain licensed asbestos materials. Following this, the controlled demolition of the buildings was undertaken, with façade retention for inclusion in the future development.
The demolition led to a significant volume of material which was crushed for re-use, on site.
Following completion of the demolition works, a number of areas of the site underwent archaeological investigation works which identified a number of walls, several wells and an historic ditch. A reduced level dig was carried out across the site to remove any obstructions which would prevent the piling foundation solution from being undertaken. During the dig, 4no underground storage tanks were identified which required the pumping and offsite disposal of the contents, followed by the breaking out and removal of the tanks and excavation of any impacted material from the vicinity. Once the tanks and any impacted soils were removed, validation sampling was carried out to confirm the absence of contamination within the remaining soils.
Once the required formation levels were achieved, Sanctus constructed a piling mat using site won recycled aggregate formed following the demolition of the previous buildings. The piling operation was then completed under the supervision of the Sanctus Project manager.
Hawkins Street, a fully operational street running through the centre of the site was to be relocated to provide sufficient space for the new development. This included the disconnection and diversion of all services running the length of the road, the excavation of the old road and following this, the installation of a new road and utilities.
Nearing the end of the project, suspected asbestos containing materials were identified beneath an area of proposed hardstanding. Additional investigation works were carried out which identified a brick structure which was found to contain significant amounts of cement bonded asbestos. Remedial works were undertaken in this area with the soils around the brick structure were excavated and processed to remove the asbestos cement fragments prior to offsite disposal. The materials within the brick structures were considered too highly impacted to warrant processing, and as such were excavated and removed from site as hazardous waste before the brick structure was broken out and the full excavation area validated to confirm the successful removal of the asbestos impacted soils.
The project was completed a week ahead of schedule, including variation works which were awarded to Sanctus throughout the project.