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

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EP-SECP-04: Down slope sediment controls

                                                                                                                               3) Suspended solids of stormwater flowing into and out of the building site:
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                                                                                                                               during stormwater events.
                                                                                                                               4) Inspection of temporary downpipe connection: after roof installation.
7. Responsibilities                                                                                                            Building contractor.
8. Reporting and
                                                                                                                               Exception reporting to the site manager and senior management.
Review

9. Contingency                                                                                                                 When significant loss of sediment down-slope is occurring:
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                                                                                                                               1) Report situation to site manager immediately, and request support;
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                                                                                                                               2) Divert flow upstream away from point of failure;
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                                                                                                                               3) Bridge the point of failure using sandbags;
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                                                                                                                               4) Collect water quality samples at inflow and outflow points (section 11);
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                                                                                                                               5) Inform relevant authorities;
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                                                                                                                               6)Implement corrective actions.
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10. Corrective actions                                                                                                         1) Improve ground cover if rills are evident;
                                                           :’;’                                                  ,.,....       2) Repair sediment fences;
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                                                                                                                               3) Remove sediment from sediment fences and stockpile (refer to EP-
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                                                                                                                               SECP-03)for later use as topsoil; and
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                                                                                                                               5) Install temporary downpipes promptly.         :.




EP-SECP-OS: Maintaining ground cover

1. Objectivesrrargets                                                                                                          To avoid erosion of soil from the building site.

2. Management Strategy                                                                                                         1) Minimise exposure of unstable soil in stockpiles and disturbed ground.
3. Tasks/Actions                                                                                                               1) Maintain existing grass c ver as much as possible;

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                                                                                                                               2) Cover disturbed gr.ound under erosion blanket, secured with pegs and
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                                                                                                                               with the edge buried below the soil surface.
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                                    L                                                                                          3) Reseed disturbed soils that will be left bare, using hydromulch or
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                                                                                                                           ,   equivalent. Irrigate reseeded_area daily for four weeks to establish the
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                                                                ~\’fj            :’r~ I...                                     4) Lay turf in areas where concentrated flow is expected (e.g. at the
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                                                                                                                               overflow of sediment fences).

4. Performance                                                                                                                 1) Lack of ground cover kept to a minimum;
Indicators
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                                                                                                                               2) Ground covered with remnant grass (undisturbed state), erosion blankets
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                                                                                                                               (short term disturbance) or reseeded grass (longer term after disturbance);
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                                                                                                                               3) Lack of surface erosion.
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5. Monitoring                                                                                ,
                                                                                                                               1) Temporarily disturbed ground is covered with erosion mats;
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                                                                                                                               2) Reseeding and irrigation of bare ground is occurring;
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                                                                                               "                               3) 100% vegetation cover 4 weeks after establishment;
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                                                                    .1..                                                       4) Rills are not present on the building site;
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                                                                     "’,L..                              D                     5) Suspended solids in water exiting the site are not excessively higher than
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                                                                                                                               water entering the site.

6. Frequency/Deadlines                                                                                                         1) Cover with erosion mats: daily;

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                                                                                                                               2) Cover with grass: daily;
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                                                                                                                               3) Reseeding and irrigation schedule is being maintained: daily;