Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:2:p2
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 2 (pt 2/4)
Character Range: 2870281–2873004

= calculated as below using Equations 19 to 21, PEFo = 3x1010 and PEFi = 2.6x107 (m3/kg)
         ETci,co = exposure time outdoors (O) or indoors (I) for young child (hours/day) = 4 hours/day outdoors and 20 hours per day indoors
    TF = indoor dust transport factor (unitless) = 0.5
    RF = lung retention factor relevant for the inhalation of dust from site (unitless) = 0.375
    EF = exposure frequency (days/year) = 365 days per year
    EDC = exposure duration for young child (years) = 6 years
         ATT = averaging time for threshold contaminants (hours, = ED x 365 days x 24 hours) = 6 x 365 x 24
         = 52 560 hours

      Equation 19
where:

    PEFO  = particulate emission factor outdoors (mg/kg soil per mg/m3 air)
         Q/C  = air dispersion factor which describes the dispersion of soil particles in the atmosphere of a theoretical outdoor box. A value of 90.8 (g/m2/s per kg/m3) has been used in the derivation of HILs. The value is a default value recommended by US EPA (2002) for small sites (0.5 acres).
    V  = the fraction of outdoor surface cover (0= bare soil), (unitless) = 0.75
         Um  = mean annual wind speed at a height of 10m (m/s), assumed to be 8.75 km/hr (or 2.4 m/s) based on the average 9 am and 3 pm winds from Canberra
         Ut  = threshold value of wind speed at a height of 10m (m/s), which is how much wind is required to generate dust at a given site from an erodible surface. A default value of 7.2 m/s has been used in the derivation of HILs (EA 2009a)
         Fx  = empirical function calculated based on the ratio of mean and threshold wind speeds as noted by EA (2009a) = 0.032 based on the following:
,   where      Equation 20

         Equation 21
where:
    DL = dust loading factor (mg dust/m3 air) = 39 µg/m3 = 0.039 mg/m3 (as per Section 5.3.3.2 of Schedule B7)
    10-6 = conversion factor for mg to kg

Calculation for Ingestion of Cadmium via Home-grown Produce
Based on Equations 15 and 16, the HILplant uptake is calculated for cadmium as follows:

         Equation 15

  Equation 16
where:

         TRVo = toxicity reference value relevant for the quantification of oral intakes, (as mg/kg/day for threshold contaminants) = 0.0008 mg/kg/day;
         BIO  = background intakes relevant to oral/dermal exposures (from sources other than soil, which include food, water, air and consumer products where relevant) (fraction relevant to the % allocated to background intakes) = 60%
         UFVC = plant uptake factor calculated for the consumption of home-grown produce by young children (kg/day) = 4.4x10-4 kg/day based on Equation 16
         CFy = plant concentration factors relevant for produce type (y), (chemical-specific) (mg/kg fresh