MCU14/0056 - Attachment G - Engineering Report & Stormwater Management Plan

                                                                                                                      ENG
                                                          Engineering Report & Stormwater Management Plan
                                                  Date:          16/06/2014     Document No.:     14012-ENG-01.Docx

                                                   By:              AvT          Revision No.:              B


                       d. MUSIC Model Results
  Using the MUSIC software. The individual treatment trains for each of the four catchment
  areas were designed to comply with the water quality objectives (WQO). It was determined
  that the water quality objectives for the whole proposed development where met as shown in
  the table below:

                                           Pre-       Post-                     Reduction         Complying
    POLLUTANT TYPES
                                       Development Development                     (%)            With WQO
Total Suspended Solids (kg/yr)             18300                 3250               82.2
  Total Phosphorus (kg/yr)                  35.8                  14.1              60.7
    Total Nitrogen (kg/yr)                  194                   101               47.9
Litter/gross pollutants (kg/yr)             989                    0                100.0
        Table 5.9:             Water Quality Treatment Results

  As shown by the above results, the proposed stormwater treatment train adopts best practise
  stormwater treatment and will achieve the required Water Quality Objectives.

                       e. Service Station and Car Wash Treatment
  The treatment of the water runoff from the service station and car wash areas has been
  excluded from the MUSIC model as these areas will be treated separately.

       Service Station and Car Wash Assessment
  While the site is not within Brisbane City Council, the acceptable solutions from the BCC
  Guidelines for Stormwater from Service Stations & Fuel Dispensing Areas (FDA) will be used as
  a reference for stormwater treatment for the service station and car wash areas under the
  building canopy and areas outside of the canopy.
  Under Canopy Areas:
      • All ground surfaces within the FDA shall be constructed of concrete with all gaps
          and/or cracks filled so that the impervious barrier and integrity is maintained.
      • The FDA shall be delineated by painted line-work on the ground. Other methods of
          delineating the FDA may be used e.g. Roll-over bunds, different colour concretes, etc.
      • Signs indicating fate of flow such as “flows to containment vessel” shall be provided in
          locations around the under-canopy area
      • The area shall be graded to a suitable underground containment vessel (i.e.
          sump/tank) compatible with petroleum products and other likely chemicals. The tank
          shall have no connections to stormwater or sewer. The containment vessel shall be
          constructed of precast concrete with a minimum certified design life of 50 years and
          be designed in accordance with AS 3600 - “Concrete Structures”. All internal concrete
          surfaces that may be exposed to contact with petroleum hydrocarbons shall be coated
          with an epoxy resin, to a minimum dry film thickness of 200 microns, applied in
          accordance with the supplier’s recommendations. Joints shall be made with epoxy or
          rubber ring seals. Epoxy joints shall be Megapoxy P1 or approved equivalent and used
          in accordance with supplier’s recommendations. For joints using a rubber ring seal,

  A PO Box 26, Carina Q 4152                                                                         14 | P a g e
  E [email protected]
  W www.vtce.com.au