Cognition was awarded a contract to remediate the basement area of a site in Guildford, prior to its redevelopment for residential and commercial use. Excavated material was processed, segregated and reused on site where possible.
Cognition was contracted to carry out bulk excavation of a basement area at a site near Guildford Station. The site is to be redeveloped as a multi-storey building for mixed residential and commercial use, built over a large basement carpark.
Site investigations within the made ground indicated that hydrocarbon, heavy metal and asbestos contamination was present. As materials were excavated, contaminated made ground was segregated and stockpiled separately from uncontaminated natural ground. A total of 35,000m3 of uncontaminated soil and 670m3 of contaminated soil was disposed off-site. Since contaminated soil is more expensive to dispose of, the processing and segregation of soil materials during the excavation works enabled Cognition to substantially reduce the disposal costs for the client.
In addition to the main remediation works, Cognition also placed a pile mat across the basement area using geotechnically suitable site won material beneath top layers of crushed concrete as an effective working platform.