Close Liaison with Local Authority and NHBC Saves Time and Money

Ruddlesden geotechnical often liaise with the local authority’s environmental health officer (EHO) and, in some instances, the petroleum officer to gain additional background information about a site. The local authority often have additional information or insight as a result of previous developments within the same area.

Ruddlesden geotechnical held favourable discussions with both the EHO and warranty provider (NHBC) regarding the risk of ground gases (carbon dioxide and methane) to a proposed residential development site in Shrewsbury, Shropshire.

Initially, the warranty provider felt that in-situ ground gas monitoring was required to ascertain the risk of gases migrating from a nearby landfill site to beneath the site. However, following joint discussions with the EHO, it transpired that historical ground gas monitoring, both on and off the landfill, had shown that the landfill had a relatively low ground gas generation potential and so was unlikely to significantly affect the site.

It was agreed that in lieu of in-situ monitoring, nominal ground gas protective measures, akin to full radon protective measures (a gas proof membrane and subfloor ventilation), could be adopted. On this occasion, this pragmatic approach saved the developer significant time and money.