2019-01-14 General Committee Agenda - Attachment 2 to Item 1 - Amended Court Approval

4377-131119-1.0                                                D> Seiten

3.0 EFFLUENT QUALITY AND QUANTITY
3.1 ASSESSMENT OF SOIL AND GROUNDWATER CONDITIONS
The soil and percolation test results indicate that the soils at the site are relatively
impermeable but is however still suitable for on-site sewage treatment and effluent disposal.
Groundwater or seepage was not observed within the boreholes carried out during the recent
site investigation.

Given the relatively poor permeability of the site soils and the presence of medium to heavy
clay soils which are more representative of Category 6 soils, the on-site wastewater
assessment for this site is based on Category 6 soils although the Borehole logs indicate the
presence of Category 5 top soils.

3.2 SYSTEM SELECTION
In order to minimise potential impacts on local water quality and to maximise the potential
reuse of treated effluent, it is recommended that all wastewater generated from the
development be treated to a minimum secondary standard. It is understood that all wastewater
generated from the dwelling and factory office facilities will be diverted to the existing septic
tank located geographically downslope of the waste generating facilities. It is proposed that
the existing septic tank will be converted to a pump station, with all collected wastewater to
be pumped to a STP capable of treating the wastewater to a minimum secondary standard.

Typical quality criteria for secondary and advanced secondary treated effluent nominated in
the Department of Infrastructure and Planning, Queensland Plumbing and Wastewater Code
are summarised in the following table:

Table 1: Quality Criteria for Secondary and Advanced Secondary Treated Effluent
              SO                   a            Acceptable Tin         Wa        5
                                                                     Acceptable Limit
       |  Suspended Solids |      mgt      | 8
       P      BONS,               mgt CT
    | Faecal Coliforms     | _—cfu/t00mL_— [200                |

February 2014                      Site & Soil Evaluation Report                          6
                                Wastewater Treatment and Effluent Disposal
                                314 Cooroy Mountain Road, Cooroy Mountain

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