Excavations for Underground LPG Bulk Tanks

Ground conditions can vary significantly and not all locations are suitable for underground LPG bulk tank storage. As a result Calor cannot accept any responsibility for any groundwork, including temporary or permanent earthwork support found necessary or foundations that may be required. It is recommended that a suitably qualified and experienced engineer be employed to undertake a geological site survey and provide the appropriate advice on all the groundwork and foundations necessary.

Due to the dangers involved with carrying out excavation work all persons who are involved in such work or working in them must be suitably trained and competent.

There is various legislation concerning persons working on, or in excavations. The emphasis is on an awareness of hazards and the methods adopted to eliminate or reduce to an acceptable level. All excavations must be assessed by a competent person to ensure they are safe to work with, both above and below ground level.

Before any excavation work commences, ensure that the following safety points are considered:

• The person who is going to supervise the digging on site has the appropriate service plans and is competent to use them.
• All workers involved in the digging know about safe digging practice and any emergency procedures and are properly supervised.
• The locator is used to trace and mark as accurately as possible the actual line of any pipe or cable.
• No cables or services are permitted within the tank excavation area.
• The site is checked with the local Water or Environmental Agency to ensure there is no risk of flooding.
• The excavation is clear of any foundations that may be at risk from undermining.
• Access is suitable for any excavation plant and crane vehicle.
• Trial holes are dug by hand using spades or shovels rather than picks and forks to confirm the position of the pipes or cables. This is particularly important with plastic pipes as they cannot be detected by normal locating equipment.

• Ensure there is good ladder access or other ways of getting in and out of the excavation safely.
• Consider the presence of hazardous fumes that can be around when petrol or diesel engines or generators are used nearby. Ensure adequate ventilation is available or arrangements made for fumes to be ducted away to a safe area.
• Battering or stepping the sides back to a safe angle is an acceptable means of preventing
  instability. The battering should take place from the bottom of the excavation.
• A competent person who understands the dangers and necessary precautions should
  check the excavation before use or after any movement of material.