HSTP Design · MCU26/0104

Page 2

Introduction

The purpose of this report is to evaluate and design a suitable on-site treatment system
and disposal area in accordance with AS 1547 – 2012, the Queensland Plumbing and
Wastewater Code, The Environmental Protection Act, The Plumbing and Drainage Act and
Local Council requirements. The report relates exclusively to the above site and the
proposed and or existing buildings shown on the plan only. All measurements and levels
shown are as accurate as possible with the information provided these are to be used for
locating the onsite effluent disposal system only.

Site Description
Weather Conditions                                               Showers
Slope                                                             0-12%
Slope Stability                                                    N/a
Vegetation                                            Grassed, scattered mature trees
Flooding                                                         Present
Watercourses                                                      Dams
Site exposure                                                   Sun & wind
Salinity                                                            Nil
Surface condition                                   Nil cracks, seepage, or compaction
Boulders & Rock outcrops                                            Nil
Will water from uphill traverse the area                           Yes
Water table                                                  Not encountered



Soil Category (AS1547-2012 Table M1)

  Boreholes                       0-200mm                      200-600mm
  BH 1, BH2                       Cat 4                        Cat 6
                                  FILL Silty Sand, Grey        FILL Silty Clay, Grey/Brown
  Perc Result: 0.07               Clay Loams                   Medium-heavy clays
                                  Weakly Structured            Moderately structured
                                  0.12-0.5m/d                  <0.06




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Page 3

Design Calculations

(The Disposal area is solely based upon the below calculation; no additional loads are to
be connected. Additional bedrooms, buildings or residents could result in failure)


 Number of Buildings                                                   1
 Number of Bedrooms                                                    4
 Number of Persons (Max)                                               6
 Adopted DIR                                                           3
 Litres per person per day (Tank supply)                              120
 Calculations                                                6x120 = 720/3=240
 Minimum Disposal Area Required                                 240sqm (min)
 Available Reserve area                                              100%



Type of Treatment
The site is to be provided with an approved (By Department of Housing and Public Works)
Advanced Secondary ASTP. The installer is to ensure the proposed final local of the
system provides sufficient fall and does not cause audible disturbance to nearby
residence.

Disposal Area & Treatment Requirements

The disposal area required is 240sqm (min).

The irrigation area is to consist of pressure compensating dripper lines buried 150-
200mm deep and spaced approximately 800mm apart.

The area is to be turfed or seeded post installation.

The installer is to ensure the HSTP is located at least 150mm above any flood levels.

The installer is to ensure the HSTP location does not cause damage to existing or
proposed footing systems, the HSTP should be anchored to prevent flotation.

All materials used are to be approved, fit for use and new. All pipework must be rated to
150% of the pump shut off.

The HSTP is to be fitted with a discharge filter with a suitable aperture, to prevent blocking
of the irrigation type installed. This should be accessible and cleaned regularly.

All stormwater from upslope is to be diverted area from the area.

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Page 4

A shallow spoon drain is to be constructed uphill of the irrigation area if deemed necessary
to divert water around the area. A 150mm high retention mound is to be installed downhill
to capture any runoff if deemed necessary.

The installer is to ensure the pump within the HSTP is sufficient to operate and pressure
the proposed irrigation system but does not over pressurize and cause the sprinklers to
aerosol.

The pipework from the HSTP shall be 25-32mm dia. purple line poly, buried within a
200mm thick sand bed to prevent damage if deemed necessary.

Control valves may be necessary to control flow and prevent misting. Spray plumes are to
be a maximum of 2m in dia. & 0.5m High. The installer should install non return valves if
needed.

The area should be constructed so there is no pooling or run off.

Two warning signs stating “Recycled Water, Avoid Contact, Do Not Drink” are to be
installed around the disposal area.

All work is to be carried out by suitably licensed person.

If soil or site conditions are found to be different from the investigation or failure is
observed, contact us immediately.




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Page 5

Maintenance and Operation of System (Owners responsibilities)
  •      Scrape all dishes to remove fats, grease, etc. before washing.
  •      Don't use a garbage grinder.
  •      Use biodegradable soaps.
  •      Use a low phosphorus detergent.
  •      Don't use powerful bleaches.
  •      Don't put sanitary napkins and other hygiene products into the system.
  •      Spray or irrigation areas should have access restricted.
  •      Divert surface water away from land application area.
  •      No vehicles or stock should be allowed on trenches, beds or irrigation areas.
  •      Deep rooting trees or shrubs should not be grown over absorption trenches or
         pipes.
  •      Where purple movable hoses (turf Valves) have been installed it is the owners
         responsibility to move. (Generally, every 2-3 days)
  •      If the designed area is grassed, it must be mowed and maintained regularly to
         encourage evaporation.
  •      Effluent is not to be disposed of outside the designed area.
  •      Vegetable gardens and/or fruit trees should not be planted within or near areas,
         where there is a possibility of airborne spray coming into contact with the plant.
  •      Structures should not be constructed near disposal areas that encourage people to
         congregate.
  •       Play areas and equipment should be well away from areas where there is no
          possibility of spray coming into contact with humans.
  •       Treatment plants and septic tanks are to be desludged every 3-5 years.
  •      We will not be liable for any Council Inspection, submission or reviewing fees due to
         changes in report or plan requested by client or Council.
  •       If any part of this design is unclear, please call before buying products or installing.
  •       This report must be approved by the local authority and appropriate permits issued
          before any work can be undertaken.
  •       The owner is to install water saving fixtures where possible.
  •       Large loads such as clothes washing should be spread out over the week.
  •       The installer is to contact Local Authorities prior to burying the system for a site
          inspection and certification. If we are required to inspect, additional fees will
          apply.
  •       Follow the manufacturer's instructions, relevant codes, standards and guidelines for
          installation, servicing, maintaining, and cleaning the system and irrigation
          area/trenches/beds.


Site Setbacks

Set back distances as per local council policies and AS1547 -2012 are to be met some of
these setbacks when Advanced Secondary with Sub-Surface Irrigation is used are;
10M from a watercourse, dam, table drain, bore etc.
10M from a dwelling or habitable building.
2M from a boundary/driveway if it slopes away or is level with that boundary/driveway.
4M from boundary/driveway if it slopes towards that boundary/driveway
6M from an inground water tank
6M from pool edge.


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Page 6

Proposed Disposal Area




Authorized Signatory




Matt Bennett




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[OCR of page images]
Proposed Disposal Area

 

Authorized Signatory

WM Excnnet?

Matt Bennett

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Page 7

 Notes
Levels shown are
approximate and are
sourced from local council
                                                                                                                                                                                                                 N
mapping or information                                                                                          Dam
provided by the client.
These levels are solely to
demonstrate the
functionality of the system.
Actual floor height is to be
confirmed with the builder
prior to installation.
All pipe work from the
structure to the proposed
system should be covered                                                                                                              Dam
and adequately vented and
be vermin/insect proof.                                                        Dam
All work carried out should
meet relevant
codes/standards and be
done by an appropriately
qualified and licensed
person.
Proposed system should be
constructed in a way to
maximize
evapotranspiration and
minimize potential pooling                                           Dam
and runoff.
If plans were not available
at the time of investigation
further reporting and
design work may be
needed prior to council                                                                                                                                      Dam
submission and installation.
Care is to be taken not to
sompact,smear or damage
the soil structure during
installation (This can lead
to premature failure).
If structures have been
built since our initial
investigation (Including                                            Dam
                                                                                                                                                             Dam
neighboring structures)
please contact us to
confirm this will not




                                                                                                                           15m
adversely effect the design.
Final landscaping and
                                                                                                                                              Proposed Advanced
installation should
                                                                                                                                              Secondary ASTP
discourage and limit causal
                                                                                            BH1
pedestrian access.(By way
of plantings, border,
mounds, visual and or                                                                Proposed Sub-Surface
physical deterrents)                                                                 Irrigation Area - 240sqm
The owner should obtain                                                              (20 x 12m)
knowledge on how to use
and maintain the proposed
system. Most of this is
available from your chosen                                                 Reserve Area
supplier/installer.                                                                           BH2
This report must be
approved by the local
council prior to any work
commencing.



                                                                                                                                 Dam


                                                                                                                                                                                     M & K Bennett Pty Ltd ATF The Bennett
Client- Lorensen Wastewater                                                                                           Abbreviations                                                  Family Trust T/A
Site - 1534 Lous Bazzo Drive, Cootharaba                                                                              BH : Borehole             DCP : Dynamic Cone Penetrometer      Onsite Wastewater Design
Date - 07/07/26                                                                                                       PT : Percolation Test     HD : Heavy Droplet Lilac Sprinkler   Gympie, QLD.
Job# - 24/348-3                                                                                                       TV : Turf Valve           RWT : Rain Water Tank                QBCC # 150 345 80
Scale - 1 : 600 @ A4 (Site features are approximate-Do not scale)                                                                                                                    E: [email protected]
                                                                                                                                                                                     W: www.wastewaterdesign.com.au
                                                                                                                                                                                     P: 0493615672