3000- Lot 7 & 8 SMP - June 2018 · OPW18/0155

Driveway and carpark areas will be passed through a Fox BPT grease/oil
arrester to remove oils and hydrocarbons prior to infiltration.

Main roofed areas will drain to a Rainwater Harvesting Tank in each building
with captured runoff utilized for landscape irrigation. Tank overflow will be
directed to catchment specific RIPs.

Runoff from main landscaped areas will be intercepted by an earth berm
located along the site’s western boundary and conveyed via a landscaped
swale to a series of RIPs and shallow landscaped basin for each building. RIPs
will be aggregated within the basin and flows greater than the design event
will be directed toward the Ecological Restoration Area as dispersed sheet
flow via a broad weir.

Similar arrangements will apply for minor building and landscaped areas
adjacent Serenity Close although flows greater than the design event will
surcharge toward the roadway formation.

Refer to engineering drawings at Appendix A for details.

6.0    RAPID INFILTRATION PITS (RIP’s)

RIPs consist of a bottomless stormwater pit which promotes infiltration
through its base.

Crushed rock and multiple layers of geofabric and “sacrificial sand” are
installed at the base of the RIP to protect against clogging of dune sands
below.

RIPs are subject to routine inspection and maintenance by the building’s body
corporate (refer Maintenance Schedule at Appendix B).

RIPs have been installed on all previous stages of Settlers Cove and proven to
work very well.

Refer engineering drawings at Appendix A for RIP details.

7.0    CALCULATIONS

Alta Projects engineers (formally Tate) were involved in formulation of the
over-arching development approval document and EMP1.

Such involvement included construction of a prototype RIP on the Settlers
Cove site and field testing to determine infiltration rates. Results were


__________________________________________________________________________

S3000/ST4/SMP/June 2018                                                      Page 3 of 3
SH/tk
                          Brah101 Pty Ltd t/as ALTA PROJECTS