Swmp

5.3.2    Sources of Contaminants
Gross Pollutants

Gross pollutants include litter, grit and heavier sediments which can be mobilised from within or from
neighbouring sites.

Potential Causes

         •      Unsecured refuse areas.
         •      Un-landscaped areas prone to stormwater scour.
         •      Insufficient drainage for surface runoff from within the site.
         •      Wind Bourne transportation.

Mitigating Measures

         •      Well established refuse areas with ample storage bins. Fenced off where deemed
                necessary.
         •      Provision of ample litter bins across the commercial footprints of the site. Particularly in
                any outdoor dining or areas of congregation.
         •      Promotion of stormwater surface runoff through landscaped areas or similar sediment
                buffering strips/traps.
         •      Provide stormwater pits outside paved areas that receive runoff from areas prone to gross
                pollutants with surrounding buffering measures, such as stone pitching.
         •      Provide gross pollutant inserts into stormwater pits within paved areas that receive runoff
                from areas prone to gross pollutants.

Hydrocarbon Runoff:

Hydrocarbons can be mobilised and transported in stormwater runoff from the site. This can contaminate
stormwater runoff compromising Water Quality Objectives.

Potential Causes

         •      Leaks from parked vehicles within the completed development.
         •      Washing of vehicles within the completed development.

Mitigating Measures

         •      Fall driveways and parking areas towards adjacent landscaped strips, vegetated swales
                and the bioretention bed.




SCG Consulting Engineers                    Page 10                                  SCG Ref: 33132(SWMP)