While performing the Topsoil validation, small quantities of cement-bound asbestos fragments could be seen just below the placed Topsoil in an area of the site. Following delineation of the affected area through additional trial pits, the client decided that rather than remove the affected soils from site, these could be remediated in–situ based on an agreed Method Statement.
Ground & Water’s Approach
Remediation was achieved by Non-licensed Asbestos Remediation trained Ground & Water Engineers and Technicians, working with strategic partners. Following excavation of the Topsoil covering the asbestos contamination, hand-picking of the cement bound materials commenced. The removed layer was stockpiled and further hand-picking was undertaken, to ensure there had been no cross contamination. This was undertaken by Ground & Water’s and strategic partners, wearing full PPE (Tyvek suits, face-fitted respirators, gloves, boots & eye protection). During the process they also actively assessed the risk of fibre release.
Following the stockpiling and hand-picking of soils, a visual inspection was carried out and representative samples were taken from both the reduced level void of the site area, the stockpiled material and the surface level immediately surrounding the site area to test for asbestos contamination. This revealed no visual evidence of asbestos containing materials in the vast majority of the void and soils excavated, with the exception of a thin band of materials at ~2.0m depth, where the site levels had been raised.
Given the depth at which these materials were encountered, beyond any zone of influence from end-users and given the end-use was a landscaped garden, it was concluded that the site area where remediation had been undertaken was now safe for its intended use.
Exercising the in-situ method of remediation kept costs and the resulting delay to the client’s move-in date to a minimum. It also significantly reduced the environmental impact by removing the need for road transport to a disposal site.