Case Study: Olympic Park Ground Investigations
Client: Olympic Delivery Authority
Engineer: Atkins / Halcrow
Main Contractor: BAM Nuttall & Morrison
BAM Ritchies carried out ground investigation work on this prestige regeneration site with challenging and contaminated ground conditions in the Lower Lea Valley brownfield site in East London. The Olympic park is split up into zones and within each zone are a number of “sites”. BAM Ritchies worked in 88 of these sites and produced a factual report for each one.
The BAM Ritchies team comprised up to seven geotechnical engineers and up to five rigs including a ‘Sonic’ rig and a lorry mounted CP rig from Holland. These were used to drill holes up to 50m deep to reach the Thanet Sands or Chalk and gravels in the contaminated areas.
The majority of these holes had gas/ groundwater monitoring wells installed and for each well, gas and groundwater monitoring/ sampling was undertaken. Some of the holes were also subsequently decommissioned by BAM Ritchies.
The detailed work content carried out by BAM Ritchies involved:
- Approximately 1400 exploratory holes, of which some 900 were boreholes
- 13 for geophysics
- 200 deep geotechnical investigation holes
- 700 shallow contamination holes
- 200 trial pits
- 300 window samples
Based on an average depth of four metres per window sample hole, four metres per trial pit, 10 metres per shallow hole and 30 metres per deep hole, BAM Ritchies has excavated some 15,000 metres and taken approximately 30,000 samples. Also, approximately 700 DP’s were carried out on the site.