Site Background & History
The site is located on the south side of the Coventry Road in the Sheldon area of Birmingham. The site occupies 2 hectares and is being redeveloped for retail purposes including a Morrison’s supermarket – see Figure 1. The site had recently been cleared and previously comprised of two large office blocks with associated car parks and hardstanding. Prior to the construction of the office blocks the site formed part of an engineering and locomotive maintenance works (circa 1950’s) and was subsequently utilised as a plant hire depot.
The site investigative work was undertaken by GIP acting on behalf of Chase Midland Estates Limited. GIP identified the presence of hydrocarbon contamination in the area of the site associated with the former engineering and locomotive maintenance works / plant hire depot. The nature of the contamination was consistent with historical activities on site.
The site investigative work carried out by GIP identified total petroleum hydrocarbon [TPH] contamination in both soils and groundwater included the presence of free product. TPH contamination within soils was considered to be significant – the maximum identified concentration was 104,000mg/kg confirming the likely presence of free product. Borehole sampling and analysis confirmed that the underlying groundwater was also significantly impacted – the maximum identified concentration exceeded 3,400mg/l. There were clear identified risks to both potential human health and groundwater receptors – the prime groundwater receptor being the nearby Hatchford Brook.
A number of remediation options were considered and precluded on the basis of cost and / or inability to achieve site remediation within the required timeframes. Working closely with Chase Midland Estates Limited [Chase], GIP, Birmingham City Council and the Environment Agency [EA], a commercially viable remediation strategy was developed which addressed identified human health and environmental concerns and also enabled the site to be developed by discharge of planning conditions relating to site contamination issues.