Pre Purchase Audit of a Service Station, East Lancashire Road, Kirkby, L33

Case Study Reference: CS22-02-07

Planning Authority: Knowsley Metropolitan Borough Council

Planning Reference:

Synopsis:

Given the past use of the site as a service station a pre purchase audit was required in order to assess the potential issues with redeveloping the site and the liabilities associated with the site. Demeter Environmental were commissioned to prepare reports to provide additional information on the risks associated with the site.

The first stage of the work 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 by the 1937 map and was likely developed at the same time as the building of the East Lancashire Road, subsequent maps identify the site as a garage. Street level imagery indicate the site was a service station. An internet search confirmed the East Lancashire Road was opened in 1934.

The planning history of the site was reviewed as part of the desk based research and the reports associated with the previous application were located and studied, four previous applications were noted and whilst the documentation did not provide any salient information the applications indicated the site had not been used as a service station from at least 1999.

Reports (soil vapour survey) provided by the vendor confirmed a number of petrol and diesel tanks were present on the site and identified area of concern.

The published geological maps identified the drift soils as Shirdley Hill sands on the eastern area with Devensian Till present across the majority of the site., the drift was underlain by the Chester Formation (sandstone). The borehole section sheets published by the BGS were reviewed and one borehole 40m south west of the site was noted, this recorded sandstone at 1.7mbgl.

No boreholes in close proximity to the site were available hence no further information on ground conditions could be obtained.

Deposits of made ground were noted 91m east and 168m south of the site..

Data provided by regulatory bodies confirmed the site had been occupied by a garage.

 

 

On completion of the desk based research a site reconnaissance visit was undertaken in order to obtain further information on the potential sources identified in the desk based research and to identify any other potential sources. The walkover survey confirmed the western area was landscaped with the eastern area being occupied by a former service station being used as a hand car wash at the time of the survey.

The locations of the tanks were identified as well as the locations of the former fuel dispensers. No evidence of the removal of any of the infrastructure was identified and anecdotal evidence suggested the infrastructure was in place and had not been decommissioned.

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 the site had the potential to be impacted by hydrocarbon contamination and further works were required in order to characterise this risk.

Further works were not feasible due to the issues with working in what was essentially an active service station due to the risk of explosion fo fuel vapours.