Septic Tanks & Cesspools

For the Settlement, Storage and Disposal of Effluent for Domestic and Commercial Applications

The CPC units are available in two shapes, spherical and cylindrical, and include sizes suitable for all applications from a single household to a large industrial or commercial complex.

CPC septic tanks are designed to meet both the installation requirements and the standards of discharge specified by BS 6297: 1983.

CPC tanks are used for domestic sewage disposal where connection to a mains sewer is not practical.

The septic tanks in the range all achieve a high degree of settlement, producing a quality of effluent for discharge to a land drainage system.

Septic Tanks & Cesspools

A septic tank consists of a two or three chamber system that retains sewage from a property for sufficient time to allow the solids to form into sludge at the base of the tank, where it is partially broken down through anaerobic digestion. The remaining liquid in the tank then overflows from the tank by means of an outlet pipe to a drainage field.

Spherical septic tanks and cesspools are manufactured as standard from 2,800 to 9,000 litres net working capacity.

Cylindrical septic tanks are available with capacities from 12,000 to 54,000 litres. The cylindrical tank allows reduced depth excavation in comparison with the same size of spherical tank, offering considerable savings where ground conditions are difficult or where there is a high water table.

The spherical tank is the simplest and most economical solution to domestic sewage disposal		The cylindrical tank allows reduced depth excavation, resulting in cost savings

Septic Tank and Cesspool Selection Chart

Cesspools are designed for storage only, with their contents being emptied at regular intervals using tankers. High Level Alarms with audible and visual warnings are available for all tanks to enable level monitoring for optimum use.

When sizing a cesspool for domestic properties it must be noted that under the Building Regulations it must have a minimum capacity of 18,000 litres (2 people) under Environment Agency regulations.

When siting units there are a number of factors to be considered. Systems should not be positioned closer than 7 metres to any dwelling and as far as possible from any watercourse, normally not less than 10 metres. Adequate access to tankers for emptying should also be taken into consideration.

Silage Effluent Tanks

CPC silage effluent tanks are manufactured using special resins, designed to be resistant to aggressive silage effluent for a minimum period of 20 years and to comply with all statutory regulations.

Silage effluent has the potential to cause severe environmental damage if allowed to enter a watercourse. Silage effluent has a very high BOD (Biochemical Oxygen Demand), up to 200 times greater than that of domestic sewage. Therefore, if it enters a watercourse it can very quickly remove all of the oxygen and kill off all aquatic life within the ecosystem. As silage effluent has caused numerous severe pollution incidents in the countryside, there are now a number of very strict statutory controls to regulate its collection and storage.

Under the 'Control of Pollution (Silage, Slurry and Agricultural Fuel Oil) Regulation' of 1991, a number of very strict rules must be adhered to with respect to the storage and removal of silage effluent. These regulations are enforced by the Environment Agency in England and Wales and infringements of these regulations may result in prosecution and fines.

Contact Clearwater Process Control for advice on the design, construction and installation of your silage effluent tank requirements.