Conversion of Outbuildings of a Public House to Retail Units / Apartments, Garstang, Preston, Lancashire, PR3

THE PROJECT

Site context.
Practical findings.

Given the sensitive nature of the development (residential) and the history of the site a contaminated land planning condition was attached to the decision notice for the proposed development.

The first stage of discharging the condition was to prepare a Phase I desk study report in order to determine if the site has the potential to be impacted by elevated levels of contamination, and to determine the source as well as the likelihood of the risk occurring.

A desk study determines what issues relating to historical contamination may affect the site, this is undertaken by reviewing the site history using a combination of O.S. maps, aerial, plates and street level imagery, a review of data held by regulatory bodies (Environment Agency, local authority, BGS etc.) as well as a site walkover survey.

The history of the site and surrounds were researched using a combination of Ordnance Survey (O.S.) maps, street level imagery and aerial plates, this revealed the site was developed prior to the first edition O.S. map when the site was occupied by a building.

A number of in-filled ponds as well as works and a garage were noted in close proximity to the site. Street level imagery confirmed the building on site was a songe story brick building, likely an outbuilding.

The planning history of the site was reviewed as part of the desk based research and the reports associated with any previous application were located and studied, no salient information was obtained

The published geological maps identified the site as being underlain by Devensian Till, which in turn was underlain by the Sherwood Sandstone Group.

Data provided by regulatory bodies identified an electricity substation 30m west of the site.

On completion of the desk based research a site reconnaissance visit was undertaken, this confirmed the building identified on the street level imagery was present on the site, the building was in a state of disrepair.

Once the walkover survey was completed a qualitative risk assessment was undertaken on the potential sources of contamination identified in the desk study report in order to determine if any warranted further investigation, this concluded that there were no credible sources of contamination and the report concluded that the made ground on the site posed a risk to water mains and building fabric. The report proposed that water mains should be specified as barrier pipe and samples of the exposed soils following demolition would be subject to pH and water soluble sulphate analysis.