R17 Soakaway, septic tank and sewage treatment units
R17 SOAKAWAY, SEPTIC TANK AND SEWAGE TREATMENT UNITS
To be read with Preliminaries/ General conditions.
PRODUCTS
R17/305 BELOW GROUND DRAINAGE SYSTEMS – PRODUCTS
- Products generally: As section R12.
R17/315 MODULAR PLASTICS SOAKAWAY UNITS
- Manufacturer: SEL, Stormer Hill Works, Tottington,
Bury, Lancashire, BL8 4AT, Telephone: 01204 885555, Fax: 01204 885533,
E-Mail: , Web: www.selel.co.uk
- Product reference: SEL HPSC System: High performance soakaway system that is intended to be installed at shallow depths.
Refer to Drawing numbers: 998(2-)04 CI & 998(90)06 CI
System To include the following:
· SEL High Performance Soakaway Conduit (HPSC) Specification: Product Code: SELW13101
Material: Polypropylene core and polypropylene geotextile surround
Volumetric void: 92%
Effective perforated surface area: 59%
Short term compressive strength: 715 kN/m2
Nominal size: 2124 x 354 x 300mm deep
Weight: 18kg
· Saddle connection to allow secure fixing of drainage pipework:
Product Code: SELW06502
· 315mm Ø Rainwater downpipe filter chamber: Product Code: SELW13202
· 500mm Ø dissipation chamber: Product Code: SELW05038
System to be fully designed and warrantied by manufacturer.
- Installation: All in accordance with manufacturers recommendations.
R17/335 PIPES, BENDS AND JUNCTIONS – CLAY PERFORATED
- Material and standard: Vitrified clay to BS EN 295-5, Kitemark certified.
R17/350 PIPES, BENDS AND JUNCTIONS – PVC-U – SOLID WALL PERFORATED
- Standard: To BS EN 1401-1 with flexible joints.
EXECUTION
R17/605 BELOW GROUND DRAINAGE SYSTEMS – EXECUTION
- Execution generally: As section R12.
R17/625 SOAKAWAYS – GRANULAR FILL
- Geotextile membrane: Line bottom and sides of pit.
- Jointing: Overlap 300 mm.
- Inspection and distributor pipes: Insert as required.
- Fill: Granular material – rubble.
- Height: Up to invert level of inlet pipe.
- Top of fill: Cover with geotextile membrane.
- Backfill: As-dug material.
- Access covers: Bed and haunch continuously in 1:3 cement:sand mortar.
R17/647 LAYING CABLE DUCTS
- Drawlines: Thread through during laying.
R17/650 BACKFILLING WITH AS-DUG MATERIAL
- Material: As excavated from the trench.
- Placing and compaction: Maximum 300 mm thick layers, up to finished ground level. Compact each layer before placing the next.
- Heavy compactors: Do not use before there is 600 mm of material over pipes.
COMPLETION
R17/910 COMMISSIONING OF SEWAGE TREATMENT UNITS
- Testing: Test the operation of all pumps, valves, controls, sensors and the like to verify correct operation, and make good if necessary.
- Hand over at completion:
- Manufacturers’ operating and maintenance instructions.
- Tools for operation, maintenance and cleaning, including keys for access covers.
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