REFERENCED DOCUMENT Assessment of Existing Wastewater Infrastructure - MCU13/0064

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             1st July 2013
                                                                               Our Ref: 4225-130402-1.2
                                                                            Application No: MCU13/0064



             The Chef Executive Officer                      CC:     General Manager
             Sunshine Coast Regional Council                         Makepeace Island (Operations) Pty Ltd
             Sunshine Coast Mail Centre                              PO Box 672
             Locked Bag 72,                                          Tewantin Qld 4565
             QLD 4560

             Attention: Assessment Manager                           Attention: Nick Jones


                                     MATERIAL CHANGE OF USE – 13/0064
                                  EXISTING WASTEWATER INFRASTRUCTURE
                                  MAKEPEACE ISLAND, NOOSA NORTH SHORE

             We refer to the above project and the Information Request from the Sunshine
             Coast Regional Council (SCRC) for the proposed Material Change of Use
             (MCU13/0064) at Makepeace Island, Noosa North Shore. In accordance with the
             Information Request from the SCRC, additional information has been provided to
             demonstrate the suitability of the existing wastewater treatment plant and effluent
             irrigation area.

             An assessment of the existing wastewater infrastructure currently servicing the
             accommodation facilities at Makepeace Island was undertaken by Future-Plus
             Environmental on the 2nd April 2013. The assessment of the on-site effluent
             disposal system was undertaken to determine its suitability to cater for the
             proposed change in use from non-publicly available accommodation to ‘letting of
             individual rooms of an existing detached house for short term visitor
             accommodation’. The number of rooms, guests and facilities remains relatively
             unchanged from the original assessment completed by Future-Plus Environmental
             (FPE) in 2007.

             This report summarises the findings of the site assessment, including an
             assessment of the hydraulic loading and effluent irrigation rate associated with the
             proposed change in use.


             Existing Infrastructure & Sizing

             The Makepeace Island accommodation facilities are currently serviced by a
             Department of Housing and Public Work (DHPW) approved, Advance Secondary
             Novaclear Aerated Waste Treatment System (AWTS) and an associated effluent
             disposal area.



p: 07 5450 2688                         e: [email protected]                        PO Box 1250, Buddina Q 4575
f: 07 5450 2686                         www.future-plus.com.au                            ABN 23 658 506 336

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             In accordance with the original Site and Soil Evaluation Report (ref no. 2771-02)
             completed by FPE on the 20th June 2007, the AWTS is to have a peak design
             capacity of not less than 2,475L/day (13 equivalent persons (EP)). Based on
             information supplied by the existing service agent (H2Gold), the AWTS currently
             has the peak design capacity of up to 2,700L/day (14 EP) and wet weather storage
             capacity of 10,000L. The existing AWTS also has the ability to expand the peak
             design capacity of the system through the modification of the internal pump
             timing. This is considered to be satisfactory. Photo Plate 1 contained in
             Attachment 1 of this correspondence identifies the existing STP.

             Treated effluent is currently irrigated via a subsurface irrigation system within
             two (2) designated effluent disposal areas. The disposal areas were originally
             designed for 495m2 however a total area of 540m2 of raised garden beds was
             installed for conservative purposes. The existing raised garden beds have the
             capacity to handle a daily irrigation rate of 2,700L based on Table M1 of
             AS1547:2012. At the time of the inspection, the effluent disposal areas appeared
             to be in good condition, with consistent ground cover. Photo Plate 2 contained in
             Attachment 1 of this correspondence identifies the existing land application area.


             Wastewater Hydraulic Loading

             In accordance with the proposed change in use, the accommodation facilities
             located at Makepeace Island will have the capacity to cater for a total of twenty
             (20) guests, located in a series of free standing buildings. In addition to the guest
             accommodation facilities, a total of five (5) staff members service the island, not
             including cleaning staff provided by an external company:

                     Two (2) staff members (traditionally Chef and Hostess) are permanently
                      accommodated on-site within the caretaker’s residence.
                     Two (2) staff members (traditionally Skipper and Maintenance) access the
                      island between the hours of 7am to 10pm. However, during high
                      occupancy, the two (2) staff members can also be accommodated onsite.
                     One (1) additional staff member (traditionally General Manager) accesses
                      the island between the hours of 7am to 10pm.
                     Two (2) cleaning staff members are provided by an external company and
                      access the island for a period of approximately six (6) hours to undertake
                      pre and post guest cleaning.

             The hydraulic loading associated with the guest and staff accommodation
             facilities can be most reliably calculated using Chapter 5 Table A of DEHP
             (formerly DNR&M) Planning Guidelines for Water Supply and Sewerage, as
             follows:




p: 07 5450 2688                       e: [email protected]                     PO Box 1250, Buddina Q 4575
f: 07 5450 2686                       www.future-plus.com.au                         ABN 23 658 506 336

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               Table 1: Calculated Hydraulic Wastewater Flows from DEHP (formerly DNR&M)
                                                                        Daily Sewage
                                                         Rooms per                          Total Daily Sewage             Adopted Total
          Item             Source          Quantity                    Flow per Room
                                                          Structure                            Flow (L/day)                 Flow (L/day)
                                                                           (L/day)
           1            Bungalow(s)            3              2           300 – 6001            900 – 1 800                    1,350
           2            Long House             1              4          225 – 4502             900 – 1 800                    900
                           Onsite
           3             Caretaker’s           1              1          225 – 4502              225 – 450                     225
                       Residence (Two
                       Resident Staff)
                       Additional Staff
           4           Accommodation           1              1          225 – 4502              225 – 450                     225
                         (Two Staff
                         Members)
                                                                                                      Total (L/day)            2,700
               Note: 1Flow per person based on two (2) bedroom Apartment/Home Unit with reticulated water supply
                      2Flow per person based on one (1) bedroom Apartment/Home Unit with reticulated water supply




               The hydraulic loading associated with the non-resident staff population can be
               most reliably calculated using the DEHP (formerly DNR&M) Determining
               Capacity of Sewage Treatment Plants Based on Use Conditions, as follows:

               Table 2: Calculated Hydraulic Wastewater Flows from DEHP (formerly DNR&M)

                                                                                                        Total Daily Sewage Flow
               Item              Source              Population          Flows (L/day/pp)
                                                                                                                 (L/day)
                           Non-Resident Staff
                  1       Member (E.g. General            1                     301                                   30
                               Manager)
                             Non-Resident
                  2          Cleaning Staff               2                     15                                    30
                               Members

                                                                                      Total (L/day)                   60
                      1Flow per person based on Non-Resident Staff at Hotels/Motels type facility



               Based on the above references, a total hydraulic loading of 2,760 litres per day
               (14EP) can be estimated for the guest and staff accommodation
               facilities/population at the Makepeace Island accommodation facility.
               On-Site Wastewater Land Application Area

               Effluent irrigation currently occurs via subsurface dripper lines within the existing
               raised garden beds, totalling 540m2.

               Based on the estimated hydraulic loading of 2,760L/day, the required effluent
               irrigation area can be determined using Design Irrigation Rate (DIR) calculation
               as set out in Table M1 of AS1547:2012.


p: 07 5450 2688                                    e: [email protected]                                    PO Box 1250, Buddina Q 4575
f: 07 5450 2686                                    www.future-plus.com.au                                        ABN 23 658 506 336

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             Table 3: Minimum Required Irrigation Area

                                                      Irrigation Area as Determined by Table M1
                        AS1547:2000 Soil Category
                                                      of AS 1547
                           Soil Category 2 – Sand                      552m2


             From Table M1 of AS1547:2012 assuming a hydraulic loading of 2,760 litres per
             day and a Category 2 soil (DIR of 5mm/day), a minimum application area of
             552m2 is required.


             Suitability of Existing Wastewater Treatment System and Land Application Area

             Based on information supplied by the service agent (H2Gold) the existing
             Novaclear AWTS has the capacity to handle a peak hydraulic loading of
             2,700L/day. However, based on the relevant guidelines a peak hydraulic loading
             of 2,760L/day (14EP) was calculated. Therefore, through the modification of the
             Novaclear AWTS pump timing, the peak design capacity of the system is to be
             expanded to handling 2,760L/day (14EP).

             The accommodation facility is currently serviced by a land application area of
             540m2, based on a daily irrigation rate of 2,700L (peak load). However, based on
             the calculated hydraulic loading of 2,760L/day a minimum land application area
             of 552m2 is required. Therefore, it is proposed to limit the daily irrigation rate to
             2,700L through the modification of the irrigation pump system. The additional
             60L/day generated during peak occupancy will be retained within the 10,000L
             wet weather storage tank for irrigation during off peak times.

             The nature of the facility would normally result in fluctuating wastewater flows,
             as it is anticipated that it will not operate at 100% occupancy at all times. Given
             that the facility has sufficient capacity to treat, manage, irrigate and if necessary
             retain effluent at times when required, the impact can be appropriately
             accommodated.

             The existing Novaclear AWTS and subsurface land application area appear to be
             in sound operating condition to accommodate the proposal.

             Provided the on-site sewerage facility is maintained in accordance with the
             recommendations provided in the Site and Soil Evaluation Report (ref no. 2771-
             02) and operation and maintenance manual, there will be minimal risk of impact
             to the site and surrounding areas. The system must be operated and maintained in
             compliance with the manufacturer’s requirements to ensure this risk is
             appropriately managed.




p: 07 5450 2688                         e: [email protected]                          PO Box 1250, Buddina Q 4575
f: 07 5450 2686                         www.future-plus.com.au                              ABN 23 658 506 336

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             We trust that the details set out above are of assistance. Please address all enquires
             to Michael Baynes of our office on 07 5450 2688.

             Yours faithfully
             FUTURE-PLUS ENVIRONMENTAL




             Paul Wood
             Director
             07 54502688




p: 07 5450 2688                       e: [email protected]                      PO Box 1250, Buddina Q 4575
f: 07 5450 2686                       www.future-plus.com.au                          ABN 23 658 506 336

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             Attachment 1
             Site Photos from Inspection 2nd April 2013




p: 07 5450 2688                        e: [email protected]   PO Box 1250, Buddina Q 4575
f: 07 5450 2686                        www.future-plus.com.au       ABN 23 658 506 336

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             Photo Plate 1: Existing Sewerage Treatment Plant




             Photo Plate 2: Existing Land Application Area No.1




p: 07 5450 2688                      e: [email protected]   PO Box 1250, Buddina Q 4575
f: 07 5450 2686                      www.future-plus.com.au       ABN 23 658 506 336

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             Photo Plate 3: Existing Land Application Area No.2




p: 07 5450 2688                      e: [email protected]   PO Box 1250, Buddina Q 4575
f: 07 5450 2686                      www.future-plus.com.au       ABN 23 658 506 336