Erection of an Apartment Complex, East Road, Longsight, Manchester, M12

Case Study Reference: 18-08-07

Planning Authority: Manchester City Council

Planning Reference: 118396/FO/2017 and CDN/19/0715

Synopsis:

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 formed part of a larger parcel of open land and appears to have been developed prior to the 1891 map, the 1893 map identified a dwelling on the site. The dwelling was demolished between 1976 and 1979. Aerial plates from 2000 to 2009 indicate a number of trees are present on the site which were cleared prior to the 2009 plate. The July 2008 street level image indicates the eastern dwelling is not the original building, the July 2015 image indicates the site is overgrown

The planning history of the site was reviewed, a document associated with application 088460/FO/2008/N2 indicated that methane was entering the sewers from Pink Bank Lane landfill.

The published geological maps (large and small scaler) were reviewed, whilst a number of deposits of made ground were noted within 250m of the site on the 10,000 scale map, only one (209m east) was recorded on the 50,000 scale map.

Both maps indicted the drift soils are Devensian Till which is underlain by Chester Pebble eds.

Data provided by regulatory bodies confirmed the presence of brick works / sand pit / refuse heap 30m east of the site as well as a landfill 185m north east fo the site (Pink Bank Land landfill)

In order to determine if the risks to controlled waters required further assessment the sensitivity of both nearby surface water courses and the groundwater in the bedrock was assessed, it was concluded that both were of low sensitivity and no further assessment was warranted,

On completion of the desk based research a site reconnaissance visit was undertaken, this identified the site was occupied by an open plot of land, the site was overgrown preventing access.

Once 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 potential for made ground to be present on site and the nearby landfill posed a risk to the proposed development.

Given that no landscaped areas were to form part of the development the pollution linkages associated with the made ground were discounted and no further works were required. Based on discussions with the client proposals for the incorporation of gas protection measures into the building were given rather than ground gas monitoring.

Once the proposals for the further works were approved the remediation strategy was prepared, which provide justification of the sufficiency of the gas protection measures as well as how the works would be validated.

The reports was submitted to discharge the contaminated land planning condition (CDN/19/0715), the recommendations of the report were accepted and the condition discharged.