Geoenvironmental and geotechnical constraints at UK parkland development
RSK carried out a geoenvironmental assessment of a 15-ha site in Paisley, UK, to support a park upgrade. The site has been a recreational space since the 19th century and the proposed development introduced turf and artificial sports pitches, a changing facility, a community events space, a cycle track and associated parking areas.
The contract, awarded under Lot 6 of the Scotland Excel Engineering and Technical Consultancy framework, comprised work to inform conditions; assess potential geotechnical and geoenvironmental constraints to redevelopment; recommend engineering solutions; and identify any remedial measures for the site. RSK completed a preliminary desk-based assessment and then designed, managed and undertook a suitable investigation to meet the stated objectives. RSK led and supervised work including two cable percussion boreholes to 27 m; eight window sample boreholes to 3 m; installing a monitoring well network; excavating 24 hand-dug pits to a maximum depth of 1.2 m; and completing 25 in-situ dynamic cone penetrometer tests, two percolation tests in accordance with BS 6297 and six rounds of gas and groundwater monitoring.
Geotechnical constraints
Our investigation showed that, owing to the presence of peat and thick, soft, alluvial deposits under the site, a piling solution or constrained modulus columns would be necessary for any new buildings. The soil had poor drainage characteristics, so we recommended that run-off be discharged to existing drainage or other possible sustainable urban drainage solutions, for example, swales, attenuation pools and permeable paving.
Environmental constraints
We identified elevated lead concentrations within made-ground soil, so we excavated an additional 16 hand-dug pits to delineate the extent of contamination. We then completed a detailed qualitative risk assessment, including statistical analysis. The assessment indicated that the site did not present a risk to users and was suitable for both its current and proposed uses. Passive ground gas protection measures were identified as a requirement for the proposed buildings, in accordance with regulations.
Added value
We engaged with the client throughout the project to minimise disruption and allow ongoing use of the park and recreation areas. The client received regular updates on the site investigation findings and any potential constraints to redevelopment. All services were completed in-house, which provided the client with a single point of contact, a better programme, increased quality assurance and cost certainty.