Ground Gas Assessment for Large Residential Development Site
After completing a Phase 1 contamination assessment, Ruddlesden were instructed to undertake a ground gas risk assessment for a proposed residential development near Rugby.
The southern and western boundaries of the site were bordered by an active landfill site and historical landfilling activities had taken place within the southwest of the site.
Twelve ground gas monitoring wells were installed to varying depths within the confines of the proposed residential development site.
The wells were monitored on twelve occasions following installation with a landfill gas analyser, for oxygen, methane, carbon dioxide and gas flow. Atmospheric pressure and other environmental conditions were also recorded.
The results of the monitoring were used to produce a gas screening value (GSV), which was used in the assessment to ascertain whether any protective measures were required for new dwellings.
The results indicated that a suitably installed gas proof membrane and subfloor ventilation would provide sufficient protection against the levels of ground gas present.