Underground LPG Bulk Tank Installation

1. You and Calor decide on the site for the tank.

2. You sign a Domestic Gas Order.

3. Calor can provide you detailed information and guidance on key safety tips to consider before, during and after the excavation process.

4. The tank is delivered and lowered into the pit and back filled. In most occasions, the original soil will be used, unless the soil contains sharp stones/objects. In which case, the soil will need to be filtered. Specific advice will be provided by your Calor area specialist.

5. A Calor approved contractor connects the tank pipeline to the house.

6. The tank is filled with LPG. Once your installer has connected the internal pipework, you can enjoy all the benefits of Calor LPG.

When vetting a site for a suitable location to install an underground LPG bulk tank, consideration must be given to the following points:

Underground Services

Sites should be vetted by a competent person at the planning stage to ensure that no services, gas, water, electricity, telecommunications, drains, sewers, cesspits etc., pass through the tank excavation area.

Plants

Trees or deep routed shrubs should not be permitted within the stated separation distances as the roots may cause damage to the tank or cathodic protection. The area over the tank may be turfed, shingled, or planted with shallow rooted, low growing flowers or shrubs. However, the need for clear access to the hood lid for filling must be taken into account.

Flooding

Tanks should not be sited in areas prone to flooding. Consult the local water Authority for information regarding the proposed site.

Consideration should be given to the provision of adequate drainage in areas of clay or water retaining soils.

Where there is a likelihood of the water table rising to a level equal to the bottom of the valve box located on the vessel then the tank shall be semi-mounded to ensure that the bottom of the valve box is a minimum of 100mm above the natural ground level.

This should ensure that the valve box containing the tank valves and fittings is not flooded and the regulating equipment controlling the supply pressure to the premise does not fail causing a cessation of the gas supply.

An LPG bulk tank will float in water. Buried tanks in waterlogged ground will be subject to a floatation force of 1 tonne per m³ and without adequate anchoring have been known to surface, bringing the pipework with them. Therefore all Calor installations use either pre cast anchor blocks or they are secured to customer cast bases using anchor points, in addition to the weight of backfill material which needs to be adequately compacted under and around the tank.

Damage by Vehicles

Tanks must not be located under public rights of way or driveways.

Suitable and appropriate protection must be provided where there is a risk of vehicles driving over the tank boundary area.

Effects on Excavation

Serious consideration should be given at the planning stage to the effect of a buried LPG bulk tank excavation on neighbouring properties and existing installation especially in cases where the tank may be sited near the property.

Due to the possible future effects of excavation work on foundations or structures it is recommended that underground LPG bulk tanks are sited wherever practical away from buildings, or structures. If there is no other suitable location within the confines of the premises then the edge of the excavation should be located no closer than 2 metres to any foundation unless a geological survey is carried out by a competent person.

Consideration should be given to the accessibility of machinery that may be required to carry out the LPG bulk tank excavation and access for the crane vehicle to position the tank.

It is important to consider the access for our delivery tanker, bearing in mind vehicle weight, height, width, the suitability of access roads and the length of the delivery hose. The driver must also be able to see the delivery tanker from the LPG bulk tank whilst filling.

Underground LPG bulk tanks must be adequately sited to ensure they can be safely placed onto their bases using appropriate lifting equipment avoiding the need for any manual handling.

Vehicles should ideally be located a minimum of 1.5 metres from any excavation to avoid the vehicle
falling into the opening, or weakening the ground around it.