Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:3:p7
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 3 (pt 7/7)
Character Range: 2952532–2956072

to soil contaminants within open space areas occurs largely in the outdoor environment and the exposure pathway of indoor vapour inhalation is not applicable. Similarly, the consumption of home-grown produce and soil adhering to home-grown produce is only applicable to the low-density residential land use scenario.

The exposure pathways considered in the development of HILs for each of the four different land use categories are summarised in Table 4.

Table 4. Exposure pathways considered for the four generic land use categories
Exposure pathways                                                                                                      Land use scenario
                                                                                                                       HIL A              HIL B  HIL C  HIL D
Indoor inhalation of dust                                                                                                                      Χ      
Outdoor inhalation of dust                                                                                                                           
Dermal contact with shallow soil and dust                                                                                                            
Incidental ingestion of shallow soil and dust                                                                                                        
Ingestion of home-grown vegetables and fruit                                                                                             Χ      Χ      Χ
Ingestion of home-grown poultry and/or eggs                                                                            Χ                  Χ      Χ      Χ
Ingestion of soil adhering to home-grown produce                                                                                         Χ      Χ      Χ
Indoor inhalation of vapours derived from soil                                                                         I                 I     Χ      I
Outdoor inhalation of vapours derived from soil                                                                        Χ                  Χ      I     Χ
  indicates exposure pathway has been considered in the derivation of the HILs
I  indicates exposure pathway has been considered in the derivation of the interim soil vapour HILs for VOCCs
Χ  indicates that exposure pathway has not been considered in the derivation of the HILs or interim soil vapour HILs

3.4              Application of the HILs to alternative land use scenarios
The generic land use scenarios used in the development of the HILs will be unlikely to accurately reflect all of the conditions present at an individual site. As the HILs are intended to represent a 'reasonable worst case' for each land use, provided that the site land use is broadly equivalent to one of the HIL scenarios, the HILs will provide for a health protective Tier 1 screening assessment. There are some limitations to the use of HILs, as described previously.

For land uses not specifically referred to in the scenario descriptions, there are two options:
    * use of HIL values for an alternate (more sensitive) land use category, as a preliminary screening tool
    * undertake a site-specific risk assessment.
The methodology presented in this Schedule may be used to derive 'HIL equivalent' values applicable to site-specific circumstances, by amending appropriate exposure settings and site characteristics values.