Underground obstructions
A number of different underground obstructions can be encountered during construction works that can cause significant delays and create safety hazards:
- Underground utility lines, including water, gas, electricity, sewage and telecommunication lines, are often located beneath construction sites. These lines can sometimes be identified using utility maps and records, but their locations may not always be accurately marked or recorded.
- Large rocks and boulders can be present in the soil and can create difficulties for excavation and construction work. They can also pose a hazard if not properly removed, as they can destabilise foundations.
- Underground structures, such as old foundations, vaults, and storage tanks, can be encountered during construction work. These structures may not be visible from the surface and can pose a significant risk to workers and equipment if not identified and managed correctly.
- Construction sites are often located in areas that have historical significance, and excavation work can uncover archaeological finds. These discoveries need to be managed carefully and properly documented, and may need to be reported, which can cause delays.
- Contaminated soil from previous industrial or agricultural activities can be present in the ground and may pose a risk to workers and the environment. This contamination can be difficult and expensive to remediate and can cause delays.
- Large trees can have extensive root systems that can be difficult to remove. These roots can also cause damage to underground pipes and cables and create instability in the soil.
- In areas with a history of mining, abandoned mine shafts and tunnels can be present in the ground. These can be difficult to locate and can pose a significant risk to construction workers if not identified and managed properly.
- Abandoned wells can be deep and difficult to locate, and if not properly filled and sealed, they can pose a risk of injury or contamination.
- In areas that have experienced military activity, unexploded ordnance (UXO) can be present in the ground. UXO can be extremely dangerous if accidentally detonated during construction work and must be identified and disposed of by trained professionals.
- In some areas, bedrock can be found close to the surface, making excavation and construction work more difficult and expensive.
- In areas that have been used for industrial activities, hazardous waste may have been disposed of in the ground. This can be difficult and expensive to remediate and can also pose health and environmental risks.
It is important that the necessary precautions are taken to identify and manage these underground obstructions before beginning excavation and construction work. This includes using appropriate surveying and ground investigation techniques to identify underground obstructions, and consulting with experts such as geologists, archaeologists and environmental consultants to assess and mitigate potential risks.
[edit] Related articles on Designing Buildings
- Archaeology.
- Brownfield site.
- Contaminated land.
- Earthworks.
- Excavation.
- Geophysical survey.
- Geotechnical engineering.
- Ground conditions.
- Ground investigation.
- Insitu testing of soils.
- Pre construction information.
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- Soil report.
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