Project Overview
Moortown Group were engaged by Kier Construction to deliver circa £20m groundworks package
on the new £200m prison at HMP Millsike in North Yorkshire. Issues included Running sand,
groundwater typically less than 1.5m BGL requiring added temporary well point, de-watering
system, invert level of pipeline varying between 5.5 to 9 metres deep.
Description of Works
Trenchless Solution Limited Engineers proposal was to utilise Guided Auger Boring to install 260
metres of DN300 in six drives at depth ranging between 6 to 9 metres deep.
Advantages of the GAB installation showed:
• Improvements to the construction programme
• Reduced H&S Risks
• Logistical challenges within the main site access routes, which would have potentially
compromised the site progress were significantly reduced.
Following discussions, it was agreed that the scope of the GAB would be increased to include the
strategic runs in the south which required a further 365 metres of DN300 in eight drives.
| Proposed Open Cut Construction | As Built Trenchless Construction | |
|
Restricted Access: • Disruption to Main Access Routes |
Restricted Access: • All Access Routes Remained Open |
|
|
Geological Issues: • Water Table Requiring De-Watering |
Geological Issues:
• No De-Watering Required |
|
| Health & Safety:
• Temporary Deep Trenches |
Health & Safety:
• No Temporary Deep Trenches |
|
| Cost Savings:
• De-Watering for Duration of the Project |
Cost Savings:
• No De-Watering Required |
|
| Environmental:
• CO2 Emissions (tonnes) as Built – 251.4 |
Environmental:
• CO2 Emissions (tonnes) as Built – 114.4 |
|
