Q&A with David Gemmell and Russell Old AECOM
Ahead of this year’s Brownfield Land Scotland 2020 conference, which is taking place on 5 February in Edinburgh, we caught up with David Gemmell, Technical Director, and Russell Old, Senior Geo-Environmental Engineer, AECOM who gave us some of their insights on overcoming the challenges of delivering a large complex remediation & redevelopment project.
Q. In your presentation summary you state - 'look at the need for redevelopment and remediation'. Did you look beyond the immediate planning requirements for the site?
A. The remediation process was used to facilitate a new slipway for the Sailing Club. There was also the added benefit of making the area accessible for the local community, and to encourage leisure and tourism use from the public again (following the restrictions applied to foreshore use in 2012).
Q. In what way did the planning permission affect remediation strategies?
A. In this case the ‘development’ was the (encapsulation) remedial solution so we were intrigued as to how planning would condition the development, particularly from a contamination perspective. As it transpired the standard (non-radiological) contamination specific planning conditions (desk study, intrusive ground investigation (GI), remediation strategy, remediation validation) were applied. As such, our GI scope (to enable detailed design) required amendment to address non-radiological contamination. Following detailed discussions with the planning team, our detailed design – in the form of a construction specification (or extracts thereof) – was accepted as a remediation strategy.
Q. Was there anything unusual in the site history or methods of discovery?
A. Absolutely. Following the original use of the landward site (and possibly areas of the foreshore) as a WW2 aircraft burning ground associated with an adjacent inland military airfield, it was upfilled with imported materials prior to subsequent development as a sailing club. Original made ground materials associated with the burning ground may also have been moved during development of the adjacent housing development. Coastal erosion processes also played a factor in the creation of preferential pathways for radiological (associated with the burning ground) and non-radiological contaminants (associated with both the burning ground and imported fill materials) to the foreshore.
Q. Could you outline some of the multi-disciplinary challenges in the remediation design phases?
A. The main challenges included consenting (EIA, stakeholder management, marine licencing, complex planning conditions), ecology (very sensitive ecological environment), landownership (four no. landowner consents required, included an operational sailing club), GI and structural/civil engineering design.
Q. Could you outline the challenges of a ‘multi-objective ground investigation’ in a publicly accessible tidal environment?
A. The main challenges included working within a dynamic tidal environment; the presence and management of radiological sources; ecological constraints (associated with nesting birds) imposed by marine licence; stakeholder interest (an operational sailing club, local residents); public accessibility (beach/public footpath); and a multi-objective GI (geotechnical, non-radiological and radiological contamination objectives).
Want to know more? Join us at our upcoming Brownfield Land Scotland 2020 conference on 5 February in Edinburgh where Russell and David will be giving a case study presentation on 'Overcoming the Challenges of Delivering a Large Complex Remediation & Redevelopment Project'.