Installation Instructions

Mascot Pits

Prior to installation, determine exact position of inlets and outlets.
Holes should be carefully formed using hammer, drill or grinder with masonry disc. Pits to be installed to levels as shown or directed by the appropriate authority. Excavation for the pit should be dug to neat lines from naturally compacted ground and to the necessary depth:

	There’s no need to ’stitch’ drill. Simply mark out where the entry is to be made and starting in the centre, softly tap the pit with a ball pein hammer.

Alternatively, for larger entries (150mm), once you have marked out the hole required, use a masonry drill to drill at 50mm

If any soft or unsuitable material is encountered, it should be removed and the bearing surface under the pit should be compacted and leveled to the required dimensions.
A layer of compacted granular material should be provided under the pit to ensure support, which will not yield or deflect when pit is in service.

All connections to pits should be in accordance with the directives of the appropriate authorities and Australian Standard AS2500.
Extension riser and surround joints are to be sealed with an approved epoxy cement mortar, to make a strong watertight joint.

It is required that you take extra measures to ensure the permanency of your installation in rock. To prevent pits from lifting or floating, as a minimum it is necessary to backfill to the top of the rock excavation with a composite of 4:1 sand/cement mix.

The pit should be bedded on a minimum 50mm layer of sand cement mortar 4 parts sand to 1 part cement ‐ back filling to top pipes or a minimum of 300mm on all sides with the same cement mortar. Further backfill to top of pit with granular material, compacted incrementally.

Compaction should not take place without the cover or grate being fixed in place. In the absence of a cover/grate, pits may be braced in both directions to prevent deflections during compaction.

Mascot GRC pits have a maximum approved height of 5000mm, however we require you provide stabilized backfill where the overall pit height is excess of 1800mm. In this event, it is required that you backfill the pit with a 4:1 sand/cement mix so that unsupported height of the pit wall is no greater than 1800mm. For example, on a 4000mm pit depth, the minimum backfill height is 2200mm from the external base of the pit.

Before attempting any above ground installation or when dealing with water charged ground, please consult your nearest Mascot Engineering Sales Office for more details.