18-0165B Stormwater Management Report_Issue D

8.4 Maintenance

Access to the proposed bio-retention basin may be gained from the internal hardstand area. A recommended
maintenance schedule for water quality treatment train is outlined in Table 4 below:

                                    Table 8 - Treatment Train Maintenance Shcedule

    Device           Task           Labour              Plant             Min.            Max        Failure Mode
                                                                       Frequency       Frequency
                                                                       per Annum
Bio-retention     Inspection      Maintenance             -                12               -        Grass
   Areas                            staff (1                                                         exceeds
                                    person)                                                          300mm in
                                                                                                     height.
                    Mowing        Maintenance         Whipper               12         As required   Ponding in
                                    staff (1       snipper/Mower                                     excess of
                                    person)                                                          24hrs.
                                                                                                     Accumulation
                   Cleaning       Maintenance         Shovel &              4          As required   of sediment or
                                    staff (2           Truck                                         gross
                                   persons)                                                          pollutants

    Outlet        Inspection      Maintenance             -                4           As required   Excessive
                                    staff (1                         During rainfall                 ponding.
                                    person)                             events.                      Downstream
                                                                                                     scouring.
                 Rectification   Environmental                         As required                   Discoloured
                                  Consultant                                                         discharge.
                                                                                                     Unacceptable
                                                                                                     odurs.




9   STORMWATER MANAGEMENT DURING CONSTRUCTION

Stormwater Quantity

    •   The stormwater disposal system shall be installed as soon as is practicable to allow for good and
        safe work environment practice.

Stormwater Quality

    •   Rubbish and the suspended solids will be adequately catered for by the erosion and sediment
        control plan.
    •   Oils and greases by volume from plant and equipment will be removed by the contractor and
        disposed in a satisfactory manner as specified by the EPA.
    •   Nutrients (ie fertilises etc will only be applied at the rates as specified by the manufacturers for the
        specified use.




HR DESIGN                                        Reference No: 18-0165D                               Page 10 of 15