Response to Information Request - Received on 19/04/2012 · OPW11/0335

EP-SECP-03: Designated on-site stockpiles and waste receptacles

10. Corrective actions                                                                                                                   1) Repair geo-Iogs, perimeter stockpile covers, waste receptacles, and
                                                                                                                                         sediment fences if required;

                                                                                                                                         2)Address upslope controls if required (refer to EP-SECP-01);

                                                                                    ,                                                    3) Building contractor to reinforce the need to keep a tidy site and cover
                                                                                                                                         stockpiles.

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EP-SECP-04: Down slope sediment controls

1. ObjectivesfTargets                                                                                                                    To reduce the transport capacity of stormwater exiting the site, and remove
                                                                                                                                         sediment from stormwater entering the site.
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                                                                                                                                         To prevent pollutants from the building site entering Noosa National Park

2. Management Strategy                                                                                                                   1)Slow the velocity of stormwater flowing across the building site;
                                                                                                                                         2) Use sediment fences to pond stormwater at strategic points in the
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                                 ~                                                                                                       3) Direct stormwater from sediment fences over grass filter strips onto
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                                                                                                                ~"                       4) Install filter socks in the sediment fence against the wetland to passively
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                                                                                        ";’                     ,      <                 filter sediment from stormwater entering the terminal wetland; and
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                                 t;IO’?~ 3:                                                                     ~:,~.                    5)Sediment curtain in the heath wetland to contain sediment that may have
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                                                                                                                                         passed the upstream ~control measures.
3. Tasks/Actions                                                                                                                         1) Install geo-textile sediment fences on the lower slopes of the building
                                                                                                                                         site. Posts should be minimum of 2 m spacing, the base should be buried
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                                                                                                                               ~         at least 200 mm belbw ground. the fenc          s should be concave   upslope to
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                                                                                                                 ~         m             bund stormwater, whi         allowing lateral 6verfl w down-slope;
                                                                                                                                         3) Stabilise grouncNhat accommodates overflow from the sediment fences
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                                                                                                                                         to avoid rill development. Refer to     EP-SEiCP-05;
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       :J        .’1                                   ~                                                                                 4) Direct overflow into’down-slope sediment fence. Filter socks will be used
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                                                                                                                                         as a final barrier to contain suspended sediment. Overflow through the filter
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                                                                                                                                         socks will be into th    heath wetland. Use water from the terminal wetland to
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                                                                                                                                         irrigate grol;!.nd.cov~r (ref r to EP-SEC -05);
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                                                                                                                                         5) Install a sediment curtain in the heat.h wetland to contain any fine
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                                                                                                                                         sediment’in overtopped sto mwater. This sediment will settle out in the
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                                                                                                                           "             wetland behind the sediment screen.
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                                                                                                                                         6) Install temporary downpipes from newly constructed roofs.                       ~\

4.Pe                           ormance.                                                                                                  1) No rill development;
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                                                                                                                                         2) Low turbidity of sediment in overflow from the sediment fence into the
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                                                                                          Jj"-~                                          heath wetland;
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                                                                                        "J                                               3) Containment of stormwater behind the sediment curtain in the heath
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                                                                                                                                         4) Prompt connection of temporary downpipes on the building site.
5. Monitoring                                                                                   ~                                        1) Rills are absent from the building site;
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                                                                                                                                         2) Build up of sediment behind sediment fences should be no more than 1/3
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                                                                                                                                         of the fence height;
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                                                                                                                                         3) Sediment fences should be structurally sound;
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                                                                                                                                         4) Suspended solids in overtopped stormwater entering the heath wetland
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                                                                                                                                         are not excessively high when compared with suspended solids entering
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                                                                                                                                         the construction site.

6. Frequency/Deadlines                                                                                                                   1) Inspection for rills: immediately after rainfall events;

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                                                                                                                                         2) Inspection of sediment fences for structural integrity and sediment.



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                "[j                                                                                                                      accumulation: weekly and immediately after a rainfall event;
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