Project: Bridge Hospital, Witham
Client: Major House Builder
Contract Value: £450,000

Knight Environmental Limited was contracted to carry out the Phase 1 and Phase 2 investigation for the former hospital site and following the transfer of ownership were awarded the contract for demolition and remediation.

Since Knight Environmental Limited were involved from this early stage we were able to offer our client a competitive package which included site demolition, site clearance, asbestos removal, removal of underground and above ground storage tanks, post demolition site investigation including geotechnical recommendations, ground remediation and regulatory liaison. Knight Environmental Limited was were the Principal Contractor throughout the site clearance, demolition and asbestos removal.

The demolition and site clearance works took place in August and September 2003 and Knight Environmental Limited undertook remediation works in December 2003 at the site.

The key objectives of the remediation can be summarised as follows:-

Limit the direct exposure of future residents and ground workers to ground contamination.

Reduce the risk to construction materials from ground contamination to acceptable levels.

Reduce the risk to future planting in landscaped areas from ground contamination.

Zonal removal of localised areas identified in the site investigation to be chemically impacted and subsequent backfilling with chemically acceptable inert soils was the most practicable remediation option to reduce the risks to human receptors.

The following key operations formed the basis of the site works required to decontaminate the site:-

1. Removal of localised areas of impaction by excavation and disposal of contaminated soil to prescribed depth below ground level.

2. Validation of the excavated areas of impaction.

The remediation scheme was approved by Regulatory Authorities prior to the commencement of the works.